p . 2 2 T h e H e a t T h a t H u r t sp . 1 8 I m p r o b a b l e B e g i n n i n g sp . 4 C o l l a t e r a l D a m a g e p . 1 2 A N e w V i e w o f C a n c e r04A U T U M N

Powerful techniques shed new light

Out of the shadowA PUBLICATION OF VANDERBILT UNIVERSITY MEDICAL CENTER

A N e w W a y o f L o o k i n ga t S c i e n c e

Lens

New hopefor bodies

on fireProgress in the

fight againstinflammation

Lens – A N e w Wa y o f L o o k i n g a t S c i e n c e

AUTUMN 2004

VOLUME 2, NUMBER 2

EDITORBill Snyder

DIRECTOR OF PUBLICATIONSMEDICAL CENTER NEWS AND PUBLIC AFFAIRSWayne Wood

CONTRIBUTING WRITERSLisa DuBoisMelissa MarinoHarold OliveyBill Snyder

PHOTOGRAPHY/ILLUSTRATIONPat BrittenDean DixonDeborah DoyleDominic DoyleMatt Gore Marie GuibertDana Johnson David JohnsonPhilippe LardyAnne Rayner

DESIGNDiana Duren/Corporate Design, Nashville

EDITORIAL OFFICEOffice of News and Public AffairsCCC-3312 Medical Center NorthVanderbilt University Nashville, Tennessee 37232-2390615-322-4747E-mail address: william.snyder@vanderbilt.edu

One never notices what hasbeen done; one can only seewhat remains to be done.

– M A R I E C U R I E

About the cover: A body afflicted by “hot spots” of chronic inflammation is surrounded

by willow trees, source of the ancient remedy salicin. Scientists are learning new ways

to quench the “fires within.”

Illustration by Philippe Lardy.

Lens is published three times a year by Vanderbilt University Medical Center in cooperation with

the VUMC Office of News and Public Affairs and the Office of Research. Lens® is a registered

mark of Vanderbilt University.

Our goal: to explore the frontiers of biomedical research, and the social and ethical dimensions

of the revolution that is occurring in our understanding of health and disease. Through our Lens,

we hope to provide for our readers – scientists and those who watch science alike – different

perspectives on the course of discovery, and a greater appreciation of the technological, eco-

nomic, political and social forces that guide it.

© 2004 by Vanderbilt University

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contentsT A B L E O F

2 EXPLORING INFLAMMATION

4 COLLATERAL DAMAGEInflammation is the body’s response to injury or infection. But the chemicalweapons used to subdue invading microbes also can damage surrounding tissue,and contribute to diseases of chronic inflammation as diverse as arthritis andAlzheimer’s disease. By deciphering the language of inflammation, scientistshope to learn new ways to quench “the fires within.”

8 THE INFECTION CONNECTIONWhat lights the fires of chronic inflammation? Persistent infection is the culpritin some conditions, including ulcers. There is evidence that it may play a role inmultiple sclerosis and premature labor as well.

12 A NEW VIEW OF CANCERTumors are not islands unto themselves. They can “hijack” normal cellularprocesses, including inflammation, to hide from the body’s immune system.They can “re-educate” inflammatory cells to release factors that promote tumorgrowth and spread. The ability to peer into this malevolent microenvironment isgiving researchers new ideas for stopping tumors in their tracks.

18 IMPROBABLE BEGINNINGSAspirin had been used to relieve pain and inflammation for more than 70 years,but no one knew how the drug worked. Then in 1971, using a generous dose of“blue-sky thinking,” British pharmacologist Sir John Vane solved the mystery. Hisdiscovery illustrates the value of basic research and the freedom to ask “Why?”

22 THE HEAT THAT HURTSWhile high cholesterol levels are a major risk factor, inflammation fuels the firesof atherosclerosis. It may play an equally important role in type 2 diabetes.Better understanding of inflammation, scientists believe, will aid efforts to diag-nose these diseases earlier, treat them more successfully and ultimately preventthem from occurring in the first place.

28 TEAMWORK AND TRUSTSir Ravinder Maini, who helped discover a new class of anti-inflammatory drugs,discusses the challenges and limitations of clinical trials, the importance of post-marketing surveillance, and the value of university-industry partnerships. Whilethese relationships must be carefully defined, they should not be discouraged, for“progress requires more than the individual can ever contribute,” Maini asserts.

32 A TORNADO IN THE BODYRheumatoid arthritis caught writer Toni Locke by surprise four years ago, tearingthrough her joints like a tornado. Read your body’s warnings and seek help early,she cautions, before irreparable damage occurs.

04A U T U M N

page 4 The winner of this battle may surprise you

page 22 A dynamic duo takes on heart disease

Lens

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which illustrates the role that trainedobservation, serendipity, initiative, andhard work play in science and medicine.Some very interesting personalities havedevoted their lives to inflammationresearch and their discoveries have hadenormous impact on human health.

Drugs that treat inflammation areamong the most prescribed therapeuticagents, and pharmaceutical companies spendbillions of dollars trying to improve them.The complexity of the inflammatory responseoffers many potential strategies and targetsfor new drug development. So this is a veryexciting and rewarding area for research.

The hallmarks of inflammation –pain, swelling, redness, and heat – andmethods for its treatment were documentedover 3,000 years ago. The Ebers Papyrus(1534 B.C.) describes the use of an infusionof dried myrtle for rheumatic and back pain.Hippocrates of Kos (400 B.C.) recom-mended a tea extract from the bark of thewillow tree for pain and fever.

In 1763, an English clergyman, theRev. Edward Stone, reported in a letter tothe Royal Society, Britain’s national academyof science, that powdered willow barkadministered in water was effective inreducing fever in a clinical study of 50 ofhis parishioners. A major component ofthese plant extracts, called salicin, was isolated in 1828 by the German chemist,Johannes Buchner. Salicin is converted inthe body to salicylic acid, which is theactual anti-inflammatory agent.

A small German dye company foundedby Friedrich Bayer developed an industrialscale synthesis of salicylic acid in the late1800s, but it was too harsh on the mouthand stomach to be very useful as a drug. Achemist at Bayer, Felix Hoffman, added anacetyl group to form acetylsalicylic acid(i.e., aspirin) and with a pharmacologist,Heinrich Dresser, found that it had prom-ising anti-inflammatory activity.

Bayer began marketing aspirin as adrug in 1899. At first sold by prescriptiononly, it became available over the counterin 1915. The synthesis and marketing ofaspirin is viewed by many as the birth ofthe modern pharmaceutical industry.

In the mid-1960s, John Vane was aBritish pharmacologist studying themechanism of action of non-steroidal anti-inflammatory drugs (NSAIDs) suchas aspirin. He was particularly interestedin the effect of NSAIDs on the productionof prostaglandins.

Prostaglandins were first discovered in 1930 as muscle-contracting componentsof human semen by the American gyne-cologists, Ralph Kurzrok and Charles Lieb.

Inflammation is a series of biochemicaland cellular events that constituteour body’s response to infection.

Inflammatory cells surround invadingpathogens and generate highly reactive andtoxic chemicals including Clorox (sodiumhypochlorite) and chlorine gas. They alsosynthesize antibodies to help clear bacteria,viruses, and other noxious stimuli, and theyproduce a range of signaling moleculessuch as prostaglandins and cytokines toamplify the inflammatory response.

This vigorous attack causes some collateral damage to surrounding tissuebut normally it is local and transient.However, prolonged exposure to inflam-matory stimuli or incorrect regulation ofthe inflammatory response leads to chronicand occasionally systemic tissue damage. Asoutlined elsewhere in this issue, this con-tributes to many important human diseases.

There is a rich history of research onthe cause and treatment of inflammation,

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Exploringinflammation A modern-day “Corps of Discovery”

By Lawrence J. Marnett, Ph.D.

DirectorVanderbilt Institute of Chemical Biology

Mary Geddes Stahlman Professor of Cancer Research

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Nearly 30 years later, the structures of prostaglandins were elucidated by theSwedish biochemists, Sune Bergstrom andBengt Samuelsson, and it was discoveredthat prostaglandins are made in many partsof the body including inflamed tissues.

Vane noticed that prostaglandinscaused some of the symptoms of inflammation and that NSAIDs inhibitedthose symptoms. He hypothesized thatanti-inflammatory drugs inhibit the pro-duction of prostaglandins, designed a setof experiments to test this, and in 1971published results that demonstrated it wastrue. These straightforward biochemicalexperiments defined the basis for thetreatment of inflammation by a class ofdrugs that had been known for millennia.For their discoveries, Vane, Bergstrom and Samuelsson were awarded the NobelPrize in medicine in 1982.

Vane’s discovery provided a rapidtest-tube screen for new anti-inflammatorydrugs and many began to emerge frompharmaceutical companies. Although theywere more potent than aspirin, their safetywasn’t much better. All NSAIDs causestomach toxicity in a significant fraction ofpeople who take them. This is due to theirability to reduce prostaglandin productionby inhibiting the enzyme, cyclooxygenase,abbreviated COX.

Since the mechanism of their anti- inflammatory activity and their gastrointestinal toxicity is the same, theredidn’t appear to be much one could do to reduce NSAID side effects. But PhilipNeedleman and Michael Holtzman fromWashington University provided evidencefor the existence of a second COX enzyme,and in 1991, Dan Simmons at Harvard andHarvey Herschman at UCLA simultane-ously identified the new gene – COX-2.

COX-2 was found to be expressed instimulated inflammatory cells but not in

the stomach, whereas COX-1 was foundin stomach and many other tissues. Thissuggested that COX-2 might be the targetfor the anti-inflammatory action ofNSAIDs, whereas COX-1 might be thetarget for their toxicity. So the race was onto develop a selective COX-2 inhibitor!

Eight years and $200 million later,Monsanto brought Celebrex to market.Celebrex was the biggest drug launch inhistory, selling approximately $1.5 billonin its first year. Merck marketed Vioxx sixmonths later, and the sales of these twoblockbusters grew to nearly $6 billionannually. These selective COX-2 inhibitorsappear to have an improved gastrointestinalsafety profile for individuals who cannottolerate non-selective NSAIDs, but theirutility for individuals who are not highlysensitive to NSAID toxicity is the subjectof considerable debate.

In September, Merck pulled Vioxx offthe market after finding that patients in along-term study who took the drug hadan increased risk of heart attack and stroke.Some experts believe all COX-2 inhibitorscan cause cardiovascular problems in certaingroups of patients. So it will be importantto determine the cardiovascular risks ofother COX-2 inhibitors and define thepatient populations that should or shouldnot be taking these drugs.

Studies of inflammation and treat-ments for it represent a classic example ofthe bi-directional translation of scientificdiscovery, from clinic to bench top and backagain. Physicians, molecular biologists,pharmacologists, biochemists, and chemistsfocus on different aspects of how inflam-mation arises, what are the importantmolecular players, how their production canbe minimized, and how one can optimizethe structure of drugs that do this.

Scientists from all over the worldbring their skills to this effort individually

or collectively as part of multi-investigatorteams. By focusing on the key events ininflammation, scientists can identify themost important studies to be conducted,and they can be assured that the resultswill have important clinical implications.This makes research in inflammation veryexciting because one can see the impact ofone’s scientific discoveries on improvedhuman health. Since inflammation con-tributes to many chronic diseases, thisimpact is further magnified.

The pace of scientific investigation is accelerating dramatically thanks in partto the development of new tools and technologies, which enable us to plan andconduct experiments that were unthinkableonly a few years earlier. Informationexchange is nearly immediate via theInternet, so the most exciting findings are communicated rapidly to investigatorsworldwide. But the basic currency of science remains – the formulation of good ideas and the design of experimentsto test them, coupled with the hard workand diligence to complete them.

Good scientists are also good innovators.They not only think about what theirexperimental results mean but they alsoask how they can use the new findings todo something that has never been donebefore. This means they are frequentlytraveling in uncharted territory, which issimultaneously terrifying and exhilarating.It is also essential to the translation ofgood science into better medicine. LENS

Bayer, along with all Germancompanies, lost its patent andtrademark rights as part of thereparations for World War I.It was able to repurchasethem in most countries,except for the United States,

so Bayer aspirin was actuallymanufactured and sold hereby Sterling-Winthrop for mostof the 20th Century. Bayereventually repurchased itstrademark from Sterling in 1994.

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In a world brimming with disease-causing germs,

inflammation is our body’s best defense against dangerous microbes.

However, when it goes awry, it can alsobe our worst enemy.

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DAMAGESaving the innocent bystander

in the battle against infection

B Y M E L I S S A M A R I N O

Humans have been battling inflammation sincethe dawn of time. Yesterday’s willow tree bark istoday’s plethora of pills and tablets. According

to IMS Health, a pharmaceutical information and consultingcompany, more than $17 billion are spent annually in theUnited States on prescription anti-inflammatory drugs.

The quest for better medicine continues today. Dozens ofcompounds are moving through the drug-development pipelineto address a growing list of inflammatory conditions.

Meanwhile, scientists are deciphering the interplay of cells,chemical messengers and genes that makes up the language ofinflammation. Along with this understanding comes an increasedcapability to intervene – to treat and ultimately to prevent thedisabling, potentially life-threatening and costly consequencesof chronic inflammation.

The language of inflammation

Inflammation begins when white blood cells – mast cells,neutrophils, macrophages – residing in tissue respond to the siteof an injury or infection. They produce waves of chemicals –called inflammatory “mediators” – that can kill germs andsound the alarm for other populations of inflammatory cells.

Unfortunately, these mediators also “can put tissue on ‘fire,’and cause ‘collateral damage,’” says Jacek Hawiger M.D., Ph.D.,who is leading the search for inflammation-related genes atVanderbilt University Medical Center.

Inflammation is a complex, multiple signaling pathwayphenomenon, but it can be broken down into three basic groupsof mediators: reactive oxygen species (ROS) such as hydrogenperoxide and “free radicals” (atoms with unpaired electrons);eicosanoids including the prostaglandins and leukotrienes; andprotein messengers called cytokines.

The production of free radicals by neutrophils andmacrophages is called oxidative or oxidant stress, and it is a critical part of infection control.

Pictured left: A macrophage, part of the firstline of defense against infection, prepares toengulf an H. pylori bacterium in the stomachlining. Unfortunately, the bacterium will survivethis encounter, as well as other inflammatoryassaults that end up damaging surroundingtissue. Eventually an ulcer may result.

Illustration by Pat Britten.

COLLATERAL

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“Oxidative stress goes hand in handwith inflammation,” says Vanderbiltresearcher Jason D. Morrow, M.D., whohas made major contributions to currentunderstanding of inflammatory mediators.“The first response is the neutrophil ormacrophage engulfing a bacterium. Then,as a consequence, is the oxidative burst thatleads to the generation of hydrogen perox-ide, superoxide and other free radicals thatacutely damage the invading organism.”

Free radicals are important in killingbacteria, but, in doing so, they can damagesurrounding tissue. Oxidative damage has been linked to the development ofAlzheimer’s disease, certain forms of cancer,and other inflammatory diseases, whichsuggests that antioxidants might be useful in preventing or treating such disorders.

Free radicals don’t last very long intissues, making it difficult to measure theirimpact directly. However, their damage can be assessed indirectly. Morrow andVanderbilt colleague L. Jackson Roberts,M.D., have identified and characterized aunique class of oxidatively-damaged fats,called isoprostanes. Circulating levels ofisoprostanes provide an accurate and non-invasive index of oxidative stress in humans.

Recently, Morrow and colleagues atOregon State University found that theextreme exercise involved in an ultra-marathon (a 32-mile run) caused increasedproduction of isoprostanes and inflammatorycytokines. Runners who took high dosesof antioxidant vitamins had significantlylower levels of isoprostanes in their bloodcompared to runners who took a placebo,but the vitamins had no effect on measuresof inflammation.

“We de-linked the protein (cytokine)component of inflammation from theoxidative stress component,” Morrowexplains. “This says that inflammation is amulti-factor pathway and not all of thosepathways are regulated in the same way –if we block one pathway (such as oxidativestress) we may still have another pathwaythat can be damaging.”

One of the other potentially destructivearms of inflammation involves lipid-derivedmolecules called eicosanoids. These mole-cules, which include the prostaglandins andleukotrienes, are produced by nearly everycell in the body. They act as local hormones,regulating many biological functionsincluding smooth muscle contraction.

Prostaglandins are also released bydamaged cells and by macrophages, andthey contribute to the cardinal signs ofinflammation. They stimulate pain receptorsin the damaged tissue, promote vasodilation(heat and redness), and increase capillarypermeability, leading to the accumulationof fluid in tissue (swelling).

Prostaglandins are made from arachi-donic acid by the cyclooxygenase (COX)enzymes, which come in two forms. In theearly 1990s, researchers determined thatprostaglandin production by one of theenzymes, called COX-1, protects the stom-ach lining, whereas activation of a relatedenzyme, COX-2, in other tissues can lead toinflammation, pain and tumor growth.

The finding led to the developmentand the marketing of drugs that specificallyinhibit the COX-2 enzyme without affect-ing the activity of COX-1. Thus, they weredesigned to relieve pain and inflammationwithout causing stomach upset and gastrointestinal bleeding, a problem withaspirin and other non-steroidal, anti-inflammatory drugs (NSAIDs) that blockboth enzymes.

The third arm of inflammatory medi-ators includes the cytokines, a large familyof messenger proteins that – among otherthings – are involved in reproduction, thedevelopment of the embryo, maturation ofblood cells and the immune response.

Cytokine production also is an essen-tial part of the inflammatory response toinfection or injury. Produced by a varietyof cells in response to injury or infection,they communicate messages that helpcoordinate the processes of healing andfighting pathogenic invaders.

Cytokines involved in the inflamma-tory response include the interferon andinterleukin families and tumor necrosisfactor-alpha (TNF-alpha). Interferons and interleukins play a variety of roles; someof them “fuel the fire” of inflammation,while others dampen it. Various treatmentsare being developed to either block pro-inflammatory members of the interleukinfamily or enhance the anti-inflammatoryactivities of others.

TNF-alpha, named for its ability tokill tumor cells, is thought to be at the center of inflammatory signaling. It canhelp recruit white blood cells to the site ofinflammation, thereby boosting productionof perhaps dozens of other cytokines.

Immunity and inflammation are almostas old as life itself.

Even amoebae, the single-celledorganisms thought to be one of the firstforms of life on Earth, are capable ofdistinguishing between members of theirown species and other species they caneat. This capacity to distinguish “self”from “non-self” is what normally preventsour more complicated immune systemfrom attacking our own tissues.

The cellular foundations of ourimmune system were laid at the time thefirst multi-cellular life forms, primordialworm-like creatures, wriggled their wayalong the ocean floor. These organismsdeveloped primitive immune cells thatheld a constant vigil against invadinggerms. Prototypes of the more sophisti-cated germ-eating macrophages anddendritic cells of our advanced immunesystem, these cells provided a form ofprotection we now call “innate” immunity.

A major evolutionary milestone occurredin jawed fishes such as sharks and rays,which developed “adaptive” immunity,the ability of immune cells to generatediverse responses against pathogens.These responses include production ofantibodies and stimulation of subpopula-tions of “T” lymphocytes that can seekout and destroy germ-harboring cells.

Adaptive immunity provides a survivaladvantage – the ability to “remember” a germ to which the human or animalhost had previously been exposed, and to mount a bigger and strongerresponse the next time the pathogeninvaded. But the cells that fight offattacking microbes also can damagenormal tissue under circumstances thatoften involve chronic inflammation.

It seems evolution has handed us aloaded gun in our immune system andthe inflammatory response. Without it, wewould be defenseless. With it, we mayjust be shooting ourselves in the foot.

– MELISSA MARINO

A survivaladvantageThe origin of inflammation

Hawiger’s group has developed a peptide that can bring production of inflammatorymessengers – commonly called the “cytokinestorm” – to a screeching halt.

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Within the last few years, severaldrugs that shut off TNF-alpha signalinghave come to market for the treatment of rheumatoid arthritis and other chronicinflammatory disorders such as Crohn’sdisease. Since TNF-alpha signalingappears to be altered in a number of otherinflammatory conditions, including can-cer, multiple sclerosis and diabetes, theimpact of these drugs may be far-reaching.

Stopping the cytokine storm

Cytokines are not the only chemicalmessengers involved in inflammation.Chemokines and cell adhesion moleculeshelp attract and direct the “first respon-ders” to the source of injury or infection,and to bring in the reinforcements once theinflammatory response has begun.

These factors aren’t always around,however. “They have to be produced ondemand – just in time when you haveinflammation,” says Hawiger, the Oswald T. Avery Distinguished Professor ofMicrobiology and Immunology atVanderbilt and chair of the department.

To provide inflammatory signals only “as needed,” the genes that expressthem must be switched on and off. This

realization has led Hawiger and his colleagues to the nucleus where, ultimately,inflammation begins.

The gene switch is operated by“stress-responsive transcription factors,”proteins that – upon activation by pro-inflammatory stimuli such as oxidativestress – slip into the nucleus and turn onthe genes for inflammatory cytokines,chemokines and the like.

Hawiger’s group has developed a peptide or protein fragment called cSN50that can keep the transcription factors outof the nucleus. This brings production of inflammatory messengers – what iscommonly called the “cytokine storm” –to a screeching halt.

Recently they tested cSN50 in miceexposed to a bacterial toxin that can causea life-threatening systemic inflammatoryresponse called toxic shock. By shuttingdown cytokine and chemokine production,the peptide dramatically reduced liverdamage and mortality, they reported in theJournal of Biological Chemistry in April.

The genomic approach may have broadimplications, since excessive cytokine andchemokine production is a central themein every inflammatory disease. About 250

genes that mediate inflammation have beenidentified so far. That’s just the tip of theiceberg, Hawiger says.

In 2001, a multidisciplinary group ofVanderbilt researchers led by Hawiger wasformed to find genes that mediate inflam-mation, with the ultimate goal of identify-ing new targets for anti-inflammatorydrugs. The NIH-funded “FunctionalGenomics of Inflammation” program so farhas developed a number of tools – includ-ing gene arrays, bioinformatics techniquesand “knockout” mice – to aid in thesearch for the “inflamed gene.”

“We are currently pursuing betweeneight and 12 genes,” Hawiger says. Thescientists plan to characterize the proteinsexpressed by these genes using proteomicstechniques to determine their precise rolesin inflammation.

“This … will help us to solidify anew paradigm of inflammation based onits ‘control center’ in the cell’s nucleus,”Hawiger says. “Thus, we will move closerto the development of a new generation of more effective and, hopefully, safe anti-inflammatory drugs tailored to tacklethe key gene players in inflammatorycells.” LENS

Pictured left: The messagestransmitted between cells bycytokines are an essentialpart of the inflammatoryresponse. Represented hereas signal beams, cytokinesproduced by the epithelium(top right) can “recruit” neu-trophils (circulating whiteblood cells, right) that can“rev up” inflammation. Meanwhile, a macrophage(bottom left) signals theblood vessel and fibroblasts(structural cells, top left) toplay their various roles infighting infection and repair-ing damaged tissue.

Illustration by Marie Guibertfor Jean-Marc Cavaillon,Ph.D., Institut Pasteur.

Genetic and environmental factors certainly may contribute to inflamma-tory conditions, but there is another, albeit controversial explanation

for them – persistent, and often silent, infections.One of the most outspoken proponents of this theory, Paul Ewald, Ph.D., of the

University of Louisville, argues that defective genes are an unlikely cause of chronicdiseases because, over evolutionary time, they should have disappeared from thehuman population. Although there are exceptions in which a mutation may be bene-ficial (such as the mutation for sickle cell anemia which provides resistance to malaria),Ewald thinks that infectious agents are more likely culprits.

“Bad genes and bad environments have often been falsely accused, or, at least, theyhave taken more than their share of the blame. Viruses and bacteria are the primaryoffenders,” he writes in his 2002 book Plague Time: The New Germ Theory of Disease.

Perhaps the most convincing evidence for his argument comes from the exampleof ulcer disease. For years, the medical community believed that stress and spicyfood caused most ulcers. However, in the 1980s a team of researchers led by BarryMarshall, M.D., at the University of Western Australia made a radical proposal –that a curiously curvy bacterium called Helicobacter pylori was the primary cause ofgastric ulcers.

Marshall proved that this bacterium was the cause of ulcers by guzzling an H.pylori cocktail. He subsequently developed gastritis, an inflammation of the stomachlining and precursor to ulcer disease, which was cured by a course of antibiotics.

Marshall’s revolutionary idea didn’t catch on immediately. “It probably tookfive or six years for the medical community to grasp the concept that ulcer diseasewas indeed an infectious disease,” says Richard Peek, M.D., associate professor ofMedicine and Cancer Biology at Vanderbilt University Medical Center.

According to the U.S. Centers for Disease Control and Prevention, H. pylori isnow considered to be responsible for 80 percent to 90 percent of ulcers and is associatedwith a two- to six-fold increased risk of gastric cancers. Approximately two-thirds ofthe world’s population is infected with the bacterium.

Yet most people who are infected never develop ulcers or gastric cancers. Why not?Peek believes the body’s inflammatory response to the infection may be the answer.

“It appears that disease results from the dynamic interactions between a particularvirulent strain (of H. pylori) and a susceptible host,” he says. “Most of these hostgenetic differences we are finding are within inflammatory genes.”

One bacterial virulence factor Peek and colleagues have identified is a group oflinked genes called the cag island. Bacteria that express cag genes are able to triggerthe production of inflammatory cytokines by gastric epithelial cells.

“Persons who have certain polymorphisms in cytokine genes can produceincreased amounts of these molecules in response to the bacterial infection,” Peeksays. This causes an enhanced inflammatory response, which is thought to be thedirect cause of gastric ulcers.

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What is the spark thatlights the fires ofchronic inflammation?Is it defective genes?Too many bacon-cheeseburgers? Toxicchemicals in our air,water and food?

BY MELISSA MARINO

(continued on page 10)

OC NNECTIONTHE INFECTION

MICROBIAL TRIGGERS OF CHRONIC INFLAMMATION

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ALZHEIMER’S DISEASEAmyloid plaques that form in brains of thosewith AD show significant amount of associatedinflammation.

ASTHMAChronic inflammation of the airways, due toallergens or irritants, makes the airways super-sensitive. Later exposure can trigger swelling ofthe airways that obstructs air flow.

DIABETESIn type 1 diabetes, the body’s immune systemattacks the islet cells of the pancreas. Recently,inflammatory processes have also been linkedto type 2 diabetes.

HEART DISEASEInflammation is likely involved in all aspects ofheart disease – from early plaque formationwithin the arteries to thrombosis, the cause of aheart attack.

INFLAMMATORY BOWEL DISEASES IBD, Crohn’s disease, ulcerative colitisChronic inflammation of the intestines may dam-age the bowel wall, allowing bacteria to “leak”through into the circulation. This may causeproblems in other body areas (including joints,skin, eyes).

MULTIPLE SCLEROSISThe body’s immune system attacks and destroysthe insulating covering of nerve cells (myelinsheath). This causes extensive scarring which,in turn, slows or blocks nerve impulses.

PRE-TERM LABORInfections in the reproductive tract during pregnancycan trigger an inflammatory response that caninitiate uterine contractions and premature labor.

RHEUMATOID ARTHRITIS AND OSTEOARTHRITISIn both types of arthritis, enzymes that breakdown cartilage are activated by inflammatorycytokines.

HOW INFLAMMATIONATTACKS:

Illustration by Matt GoreBased on the work of Andreas Vesalius

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This combination – of a highly virulentbacterium and a host that overreacts to theinfection – might be the answer to thisvexing problem.

While identifying the infectiousagent responsible for ulcers and gastriccancer was relatively easy (because H.pylori is virtually the only bacterial speciesthat can colonize the normal stomach), thepicture gets much cloudier when dealingwith other tissues. For example, Peekdescribes, “in the large bowel, there areapproximately one trillion bacteria pergram of tissue, so trying to pinpoint onespecies that causes a chronic inflammatorydisorder that affects this organ, such asInflammatory Bowel Disease (IBD), is prohibitive.”

Finding the cause of inflammatoryneurodegenerative diseases like

Alzheimer’s disease, multiple sclerosis (MS)and the myasthenias (which cause muscleweakness) is hampered by the long timecourse – often 20 years – from the onset ofdisease to severe disability.

MS is a progressive demyelinating dis-ease with periodic relapses and remissionsin which the protective myelin around thenerves is destroyed or damaged, resultingin a range of neurological symptoms.

Although the cause is unknown, MShas been classified as an “autoimmune”disease in which the immune system mis-takenly attacks body tissues that bear anauto-antigen it recognizes as foreign. Forsome diseases, like the myasthenias, anauto-antigen has been identified. But, sofar, no convincing auto-antigen has beenfound for MS.

“The inference that an inflammatorydisease is autoimmune is largely by defaultsince we are unable to find an infectiousagent,” says Subramanian Sriram, M.D.,professor of Neurology, and Microbiology& Immunology at Vanderbilt.

Just because scientists haven’t found a causative organism(s) doesn’t mean itdoesn’t exist, however. “We may haveoverlooked them,” Sriram says. “To usethe cliché, ‘absence of evidence is not evidence of absence.’”

Both a virus (human herpesvirus 6)and a bacterium (Chlamydia pneumoniae)have been proposed as inciting silentinfections that may underlie MS. However,no definitive link has yet been shown foreither of these candidates.

Although at least five labs, includingSriram’s, have found C. pneumoniae in the spinal fluid of MS patients, severalothers have not. While he thinks that the

bacterium definitely plays a role in thedisease, the nature of MS makes the linkdifficult to establish.

“We do not think it’s the cause of MS,”Sriram says. “We think it’s a cofactor – asecondary mediator, or possibly one of the polymicrobial infectious agents in thedisease process.”

Sriram and his colleagues recentlycompleted a pilot study, which suggestedthat a six-month course of antibiotics mightstabilize the brain lesions and brain atrophycharacteristic of MS. The researchers areplanning a larger, longer-term study, whichwill be necessary to prove a pathogenicbasis for MS.

“In my studies with MS, the problemin finding a link is that we have very little

tissue of patients with MS in early stages.MS is not a fatal disease, and so we obtainpostmortem brain tissue from peoplewho’ve had the disease for 40 to 50 years,”Sriram said.

“It is impossible to identify what factorscaused these lesions to develop 30 to 40years ago. What we see is the result ofsomething having happened – ‘the aftermathof a battle’.”

To address this problem, the Mid SouthChapter of the National MS Society issetting up a donor program to collectbrain tissue from MS patients who die ofcauses unrelated to the disease. This tissuewill allow scientists to examine the initialevents that cause MS.

As in the H. pylori story, the diseaseprocess likely depends on an interactionbetween the germs and the host’s responseto them. In general, Sriram agrees withEwald’s theory of infectious agents causingchronic diseases but adds, “we can’t blameit all on the pathogen. The host bears someresponsibility in the ultimate outcome.”

Premature labor, the leading cause ofperinatal morbidity and mortality

worldwide, also appears to have an inflam-matory origin. According to RobertoRomero, M.D., chief of the PerinatologyResearch Branch at the National Institute

of Child Health and Human Development,“one of every four premature babies areborn to women with subclinical infectionsof the amniotic cavity.”

Romero’s studies have shown thatchronic, often silent infections within theamniotic cavity incite inflammation of the membranes and the fetus. The mostfrequent offenders are the normal bacterialresidents of the vagina – Ureaplasma urealyticum, Mycoplasma hominis, andFusobacterium species.

“For unclear reasons, bacteria fromthe lower genital tract cross the cervix, get into the uterus, and cross intact fetalmembranes to gain access to the amnioticcavity. Microorganisms within the amnioticcavity may infiltrate the fetus when itbreathes in infected amniotic fluid, throughthe ear or even through the skin,” Romerosays. This prompts the fetus to mount anexaggerated inflammatory response, knownas Fetal Inflammatory Response Syndrome.

Inflammatory cytokines produced byintrauterine tissues and the fetus are believedto mediate the key aspects of normal laborand delivery: uterine contractions, cervicaldilation, and rupture of the membranes.However, if the fetus has a systemicinflammatory response due to intra-amniotic infection, this response may trigger premature birth.

Romero and colleagues have foundincreased levels of several cytokines in theamniotic fluid of women with infection.These cytokines stimulate the synthesis of prostaglandins, which can induce con-tractions, cervical dilation and rupture of membranes.

“A unique circumstance of the fetusis that it must live in an infected environ-ment. That problem is often solved by initiating labor,” he says. Premature delivery has its own attendant risks, however, including respiratory distresssyndrome, heart problems and blindness.

Antibiotic therapy has not been effec-tive in preventing preterm labor, possiblybecause the infection is not typically founduntil preterm labor has already begun.Instead, studies in animals suggest thatanti-inflammatory therapies – including theuse of anti-oxidants and COX-2 inhibitors –may be the best bet for stopping prematurelabor and improving neonatal outcome. LENS

“A unique circumstance of the fetus is that it must live in

an infected environment. That problem is often solved

by initiating labor.” ROBERTO ROMERO, M.D., NIH

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Perhaps the best evidence for theimportance of inflammation is what canhappen in its absence.

For 16-year-old Allen Grimes ofHopkinsville, Ky., a rare genetic disorderthat results in an insufficient inflammatoryresponse has left him nearly defenselessagainst infections.

When he was three weeks old, Allenwas diagnosed with chronic granulomatousdisease (CGD), a condition caused by adefective enzyme in his phagocytes, infection-fighting white blood cells. Theenzyme helps phagocytes produce toxicchemicals like hydrogen peroxide andbleach that kill bacteria. Without it, CGDpatients are plagued with recurrent, oftenlife-threatening infections.

To help his body compensate for thisdeficiency, Allen takes an antibiotic, ananti-fungal drug and gamma-interferon to bolster his immune system. He alsoavoids situations that could expose himto harmful bacteria and fungi.

Because crops grown in his ruralcommunity are rife with molds and fungi,“I can’t work on a farm, which is some-thing I always wanted to do,” Allen says.He also can’t have pets, swim in arealakes or be out in the sun because of hisillness and the medications he takes.

But that hasn’t kept him from partici-pating in Little League, band and now varsityfootball. His family and doctors have alwaysencouraged his active lifestyle. “We thinkit’s the best way to keep him healthy,”says his mother, Deanna Grimes.

Before the 1970s, CGD was knownas “fatal granulomatous disease of child-hood,” according to John I. Gallin, M.D.,director of the Clinical Center at the

National Institutes of Health. Two percentof CGD patients died each year.

Fortunately, by the time Allen wasborn, Gallin and other researchers haddetermined the underlying genetic defectand how to treat it. Studies of prophylacticantibiotic therapy in CGD patients in theearly 1970s were the first major step.“Low doses of antibiotics reduced life-threatening infections from one (perpatient) every year to about one everyfour years,” Gallin says.

Studies of gamma-interferon yieldedan even more dramatic effect – a 70-per-cent reduction in the number of infections.

In an apparent paradox, CGD patientsoften form areas of chronic inflammationcalled granulomas that can lead to life-threatening blockages in the esophagus,digestive system, urinary tract and lungs.Gallin, who has studied CGD and relateddisorders for more than 30 years, describesthe disease as “one of the great examplesof the good and the bad that can come of inflammation.”

Bone marrow transplants can curethe disease, but are limited by matchingdonors. Replacing the defective genethrough gene therapy showed some earlypotential, but the recovery was short-lived. Researchers led by Harry Malech,M.D., chief of the Laboratory of HostDefenses at the National Institute ofAllergy and Infectious Diseases, are nowlooking for new viral vectors that will deliverthe normal gene to patients’ blood stemcells more effectively.

With an incidence of only about oneor two cases per million people, why haveresearchers spent so much time studyingCGD? “I believe that if you can under-stand how inflammation is dysregulated inCGD, you might be able to determine themechanisms involved in other chronicinflammatory diseases like atherosclerosis,Crohn’s disease, arthritis and certaintypes of cancer,” Gallin says.

Allen and his family chalk up his current good health to a little luck, astrong faith in God and constant vigilanceagainst infection. They also are strongsupporters of research.

Allen has participated in some of thetreatment studies, and he hopes for a daywithout needles, pills or IVs. A day whenhe can swim without worrying about gettingsick. A day when he can stand in the sun.

“He’ll do whatever it takes to bringawareness to the disease, and to helpfind a cure,” his mother says. LENS

The bestdefense …is a good inflammatoryresponse BY MELISSA MARINO

Allen Grimes knows first-hand the value ofa healthy inflammatory response.

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A NewView ofCancer

THE ROLE OFINFLAMMATIONBy Bill Snyder

Macrophages are a type of white bloodcell normally involved in inflammationand fighting infection. In this case, they appeared to be attracting thetumor cells to the vessel. “It’s almost asif the macrophages are sending a ‘comehither’ signal,” says his colleague JeffreyW. Pollard, Ph.D., deputy director ofthe Albert Einstein Cancer Center inNew York.

The pictures, achieved through the convergence of multi-photon lasermicroscopy and the generation of transgenic mice with fluorescent tumors,are providing some of the first visual,real-time evidence linking cancer toinflammation in living animals, saysCondeelis, a biophysicist who directsEinstein’s Analytical Imaging Facility.

Many questions remain, but newtechnologies and a flood of researchstudies are redefining the old, relativelystatic model of cancer. Tumors areastonishingly dynamic and versatile.They depend in absolutely crucial wayson interactions with surrounding normaltissue. This new view of cancer is shat-tering old assumptions, while at thesame time raising hopes for earlier diagnosis, better treatment and, perhapsmost provocatively, prevention.

“Prevention is going to become thedominant approach to cancer within thenext 20 to 30 years … just as it has forcardiovascular disease,” predicts ErnestHawk, M.D., MPH, who leads gas-trointestinal research in the NationalCancer Institute's Division of CancerPrevention. “That will come aboutthrough an improved understanding ofthe various pathways … that influenceinflammation … And that’s where itreally starts to get exciting.”

Illustration by Philippe Lardy.

When John Condeelis, Ph.D., first watched tumorcells in living tissue under the microscope, he wasamazed by what he saw. The cells were speedingalong like little cars on fibrous “superhighways.”Their destination: a newly formed blood vesselsurrounded by macrophages.

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drug in patients with familial adenomatouspolyposis (FAP), an inherited conditioncharacterized by the appearance of multi-ple polyps in the colon that nearly alwaysbecome malignant. In June 2000, aninternational team of researchers, includingDuBois and Hawk, reported that the useof Celebrex led to a significant reduction inthe number of polyps in patients with FAP.

The landmark finding, published in The New England Journal of Medicine,opened the floodgates for studies aimed at preventing other cancers by blockingproduction of prostaglandins. Since then,DuBois and his colleagues have found thatone of the members of the prostaglandinfamily, PGE2, seems to be specificallyinvolved in spurring the proliferation and invasive potential of colorectal cancercells, and it may do so – at least in part –through the receptor for epidermal growth factor (EGF), which stimulates cell growth.

“This is what I’m really excited about,”says DuBois, the Hortense B. IngramProfessor of Molecular Oncology atVanderbilt. “It just continues to supportour whole concept from 1994, that (COX-2) is really playing a role” in colon cancer.

COX-2 is not the only performer inthis drama. During the past half-century,scientists have chronicled a burgeoninglist of growth factors, cytokines, geneticswitches and protein-chomping enzymesthat play interacting – and overlapping –roles in inflammation and cancer.

These chemicals are generated inresponse to emergencies such as injuriesand infection by a variety of cell types andthrough a variety of signaling pathways,including activation of the COX-2enzyme and the resulting production ofprostaglandins. They include:• Growth factors that trigger cell pro-

liferation, and which block signals

For nearly a century and a half, scien-tists have suspected that many cancers arecaused by inflammation – the complicatedprocess by which the body heals woundsand fights off invading pathogens.

Prime examples: colorectal cancer in patients with inflammatory bowel disease; lung cancer that follows chronicinflammation from inhaled asbestos particles; and tumors of the stomach andliver – among the most common cancersworldwide – that are linked to pathogen-induced inflammation. Inflammation alsomay contribute to the development ofprostate cancer, which, next to lung cancer is the second leading cancer killer in American men.

Another link in this causal chain wasforged about 10 years ago, when population-based studies detected a 40 percent to 50 percent drop in the relative risk ofdeveloping colorectal cancer among peoplewho regularly used aspirin.

The finding came at a fortuitousmoment: during the previous two decades,scientists had learned that aspirin workedby blocking production of prostaglandins,ubiquitous lipid-signaling molecules thatare involved in a host of physiologicalprocesses. Two prostaglandin-generatingenzymes, the cyclooxygenases, had beenidentified, and one of them – COX-2 –was known to play an important role inpain and inflammation.

In 1994, Ray DuBois, M.D., Ph.D.,and his colleagues at Vanderbilt UniversityMedical Center found high levels of COX-2in cancerous colon tissue. Three yearslater, they had stopped human colon cancer cells from growing in the laboratoryby blocking the COX-2 enzyme.

By this time, Celebrex – the firstselective COX-2 inhibitor – was on itsway to market for treatment of rheumatoidarthritis. Researchers began testing the

that otherwise would lead to celldeath, a process known as apoptosis;

• Enzymes that repair and “remodel”tissue after an injury, and which spurthe growth of new blood vessels tofeed it; and

• Immune regulators, includingcytokines, that call in the reinforce-ments of immune and inflammatorycells to fight infection and help healwounds, and others that “call off thetroops” to limit collateral damage tosurrounding healthy tissue.

These pathways exist in exquisite balance. When the balance is tipped, orwhen certain genetic switches are turnedon, some growth factors and cytokinesmay be “over-produced” while others aresuppressed. The result can be chronicinflammation, damage to tissues andabnormal growth. A growing number ofscientists believe, therefore, that under-standing the unique molecular and cellular“micro-environment” in which the tumorthrives is key to improving cancer therapyand prevention.

This is not an easy puzzle to solve.The “imbalance” of growth factors andcytokines that promotes cancer may differdepending on where in the body the tumorbegan and its stage of growth. The role ofinflammation also may differ dependingupon the circumstance.

In some cases, chronic inflammationmay trigger tumor growth. Inflammatorycells, including mast cells, neutrophils andmacrophages, can generate highly reactivemolecules of oxygen and nitrogen that canliterally punch holes in bacteria. Too muchof this firepower, however, can damage theDNA of nearby cells, leading to out-of-control growth. Limiting inflammation inthese cases could be an effective way toprevent the development of cancer.

“How do these inflammatory cells potentiate tumor development at themolecular level? What is the precise role of the microenvironment? We don’t haveanswers to that.” RAY DUBOIS, M.D. , PH.D.

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that has been shown to affect melanomatumor growth.

Three years ago, Pollard and his colleagues at the Albert Einstein CancerCenter reported that colony stimulatingfactor-1 (CSF-1), a major macrophage growthfactor and chemokine, seemed to be essen-tial in a mouse model of breast cancer for“metastasis,” spread of a tumor from itssite of origin to other parts of the body.

Mice that lacked the gene for CSF-1still developed mammary tumors, but thespread of the metastatic tumors to the lungswas significantly delayed. In addition, thesetumors did not have the normal infiltrationof macrophages seen in mice with the normal CSF-1 gene. When the gene wasreintroduced into the mice, metastasis – inconjunction with macrophage infiltration –was restored. “At least in this model,” Pollardexplains, “macrophages are bad news.”

Macrophages are not the only cell typethat can fan the inflammatory flames ofcancer. Zena Werb, Ph.D., Lisa Coussens,Ph.D., and their colleagues at the Universityof California, San Francisco have found thatcells in the connective tissue surroundingthe tumor also can send out signals thathelp it grow and spread. The cells “talk”to each other, just as they do during devel-opment of mammary glands or hair follicles.“The environmental side and the tumorside co-evolve,” explains Werb, professorand vice chair of Anatomy at UCSF.

Most cancers arise from the epithelium,the layer of cells that separate underlyingtissues from the outside world. The epi-dermis of the skin, the linings of the lungsand digestive tract – all are examples ofepithelial tissues. Underneath is the stroma,which provides the connective tissue, bloodvessels, nerves and other vital physiologicalfunctions. Between cells is the extracellu-lar matrix, which plays a role in tissuedevelopment and healing. It is here that

the cells travel on their fibrous “super-highways” from one location to another.

An example of this cellular “cross-talk”is the tissue remodeling that occurs duringdevelopment or wound healing with thehelp of the matrix metalloproteinases(MMPs), a family of enzymes involved in a wide range of physiological processes.“Not only do they degrade the matrix,they release biologically active factors thatare involved in calling in inflammatorycells and in angiogenesis,” says LynnMatrisian, Ph.D., chair of Cancer Biologyat Vanderbilt who, as a post-doctoral fellow,cloned the first full-length MMP in themid-1980s.

MMPs also are believed to contributeto metastasis, the major cause of deathfrom cancer, by helping to increase thetumor’s blood supply and means of escapeto other parts of the body. The first syn-thetic MMP inhibitor was tested in humansin 1992, but by 2002, several clinical trialshad failed to show any survival benefit.

That’s not surprising, says Matrisian,current president of the AmericanAssociation of Cancer Research. MMPinhibitors “don’t stop cancer in its tracks,”she says. “What we learned is they changethe rate of progression (of the disease).”

Two years ago in Science magazine,Matrisian, Coussens and their Vanderbiltcolleague Barbara Fingleton, Ph.D., pre-dicted that MMP inhibition would helpprolong survival to the point that patientsdied of “old age” before they died of cancer.“But you can’t give it at the ninth hour,”Matrisian says. “You have to give it earlier,or you have to give it in combination(with other drugs) … or you have tothink about prevention.”

Research is continuing. Matrisianand colleagues around the world aredeveloping biomarkers and optical imagingtechniques to determine how effectively

Mutations in other cases may resultfrom exposure to irradiation, carcinogenicchemicals or viral proteins. In this case,inflammation may be a “promoting” ratherthan initiating event. There is increasingevidence that the tumor can attractinflammatory cells, and use their growth-promoting factors to help it grow andspread. In this sense, the tumor “hijacks”the normal functions of inflammation forits own ends.

There is some evidence that tumorcells send out chemical signals – calledchemokines – that attract inflammatorycells. According to one model, macrophagesliterally roll along the lining of blood vessels, following a trail of increasinglyconcentrated chemokines, like blood-hounds tracking a scent.

When the macrophages reach the siteof the tumor, they squeeze through theblood vessel lining into the underlyingtissue. Normally, they would sound thealarm, calling other elements of the immunesystem to attack the tumor. Instead, they are“re-educated” by the tumor to produce avariety of factors that nourish the tumorand enable it to break through the connec-tive tissue that restrains it.

These “tumor-associated macrophages,”as they are called, also can release immuno-suppressive factors – various members ofthe interleukin family of cytokines – thatblunt the ability of the body’s immune surveillance system to detect and attack thetumor. So can other white blood cells(lymphocytes) that infiltrate tumors.

One possible way to stop this processand prevent tumor progression is to blockexpression of chemokines that chronicallyrecruit inflammatory cells to the site wherethe tumor is developing, suggests AnnRichmond, Ph.D., professor of CancerBiology at Vanderbilt. Richmond is co-discoverer of one of the first chemokines

Pictured right: Using a multi-photon microscopy tech-nique they developed, John Condeelis, Ph.D., and hiscolleagues at the Albert Einstein College of Medicineshowed that tumor cells (green) move on fibers in theextracellular matrix (purple), some of which converge ona blood vessel (arrow). The in-vivo imaging technique hasenabled the study of invasive tumor cells in real time.

From Nature Reviews Cancer (2003)Courtesy John Condeelis, Ph.D., and Nature

Tumorcells

Bloodvessel

fibers

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With these approaches, “you willhave determined on some level whatgenetic pathways or patterns of proteinexpression are altered in the patient’s tissue,”Richmond explains. “Then you might beable to predict which regime to use for thatpatient by targeting the defect in that specific patient’s tumor.”

For example, if over-production ofpro-inflammatory cytokines and chemokinescan be detected, and if drugs that specifi-cally target these signaling molecules ortheir receptors can be given to block thisstep in tumor progression and metastasis,“we will likely increase our success withboth prevention and therapeutic interven-tion in cancer,” she says.

What’s needed, says DuBois, is a unifying theme. “There are different com-ponents of the inflammatory response thatplay a role in cancer,” he says. “We’ve beenlooking at them individually. Hopefullypeople can go back and look at this, andtry to see if they can make sense of someof the research that’s been done.” LENS

the inhibitors block the enzymes, andnew animal models that more closelyresemble the human condition.

Other researchers are tackling metas-tasis from the point of view of the erranttumor cell that makes it into the blood-stream. In patients with cancer, “there are (an estimated) million or so tumorcells circulating at any one time, and yetonly one or two of those end up as metas-tases,” Pollard says. “Does that mean that(only) one in a million cells … is able tometastasize, or that there are a millioncells able to metastasize but only a one-in-a-million chance of them lodging inthe right place?”

One theory is that once out in thebloodstream or lymphatic system, thetumor cell tracks a “trail” of chemokinesto a specific tissue that is producing thesignal – essentially reversing the coursethat inflammatory cells took to get to theprimary tumor. “Another possibility whichis a bit … more outlandish,” he says, “isthat tumor cells are ‘chaperoned’ by (blood)cells.” In either case, the spread of cancermay be guided by specific chemokinesreleased by various tissues.

Pollard hopes the new imaging tech-nology the Einstein group has developedwill help solve the mysteries of metastasis.“We should be able to follow cells as they

move around the body in ways that we’venot been able to do before,” he says.

Ultimately, the control of cancer maydepend on a better understanding of thecomplex chemical signals that guide thesecells. “These are the big questions,” saysDuBois. “How do these inflammatory cellspotentiate tumor development at themolecular level? What is the precise role ofthe microenvironment, and what regulatesthe inflammatory cell recruitment into theneoplastic (tumor) microenvironment? Wedon’t have answers to that.”

With the help of techniques such asDNA microarray, scientists are identifyinggenes that play a role in inflammation andcancer. They’re studying what happenswhen the genes are “knocked out” inmouse models. One goal is to learn how to “manipulate” macrophages, for example,by altering the balance of cytokines in away that would turn them from thetumor’s friend to a foe.

On the clinical side, researchers aretrying to identify patterns of proteins inblood samples from patients that can becorrelated with types and stages of cancer,and their response to treatment. Anotherapproach seeks to identify groups ofpatients with genetic differences, calledpolymorphisms, who would be most likelyto benefit from targeted cancer therapies.

According to one model, macrophages roll along the lining of blood vessels,

“tracking the scent” of chemical messengers called chemokines released

by tumor cells. Once at the tumor site, they are “re-educated” by the tumor

to produce factors that help it grow and spread.

Guided by factors in their “micro-environment,” some tumor cells find their way

to a blood vessel. Once in the bloodstream, a chemokine trail – or possibly a

blood cell “chaperone” – leads them to another tissue. This process is known

as metastasis.

Macrophage

Macrophage

Macrophage

Blood vessel

Blood vessel

Tumor

Stromal layer

Chemokines

Tumor cells

Rolling along – a nefarious journeyILLUSTRATIONS BY DOMINIC DOYLE

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FORTUNE magazine created a stir in the research community last March with a coverstory entitled “Why we’re losing the war on cancer (and how to win it).”

The story’s author, Clifton Leaf, one of magazine’s executive editors and a cancersurvivor, described “a dysfunctional 'cancer culture' ... that pushes ... physicians andscientists toward the goal of tiniest improvements in treatment rather than genuinebreakthroughs.”

Leaf criticized current research efforts for “isolated (and redundant)problem-solving instead of cooperation,” and for focusing on shrinkingtumors instead of the more difficult problem of metastasis, which is“the thing that kills people.”

Scientists interviewed for this issue of Lens disputed the “dysfunc-tional” label, but they said they could make faster progress if therewere greater incentives for collaboration among researchers, cliniciansand drug companies.

“Patients are going to benefit the most from combinationalapproaches,” yet current patent and regulatory constraints make it difficult to test new drugs in combination, notes Lisa Coussens,Ph.D., a cancer researcher at the University of California, SanFrancisco. “You have to test them as single agents and if they don’t

demonstrate efficacy, they’re not going to goany further.”

Junior faculty also are discouraged from collaborating with each other because they haveto demonstrate independence in order to bepromoted and win research grants, Coussens

says. Yet that’s exactly what’s needed to make progress, maintainsErnest Hawk, M.D., MPH, of the National Cancer Institute's Divisionof Cancer Prevention.

“I’m not talking revolution here, but it’s something the whole culture needs to take a look at,” Hawk says. “Getting researchers working togetherrather than quite so independently will reduce redundancy and perhaps maximize theeffort we’re putting forward.”

Toward that end, the NCI is serving as a “catalyst” – bringing scientists from diversefields together to develop new research strategies, and pursuing partnerships withpharmaceutical companies to hasten drug discovery and development.

The discovery that Celebrex can inhibit pre-cancerous polyps in high-risk patientsemerged from just that kind of partnership. “That was just a six month trial, very fast,very small, very efficient,” says Hawk, who participated in the research, “and yet it hada profound impact … both for immediate clinical care of a high-risk group and thenmore broadly for the potential of many others.”

Tests of other potential drugs have been disappointing, in part because of the way theyare tested both in animals and humans. “When we give a mouse cancer, we start treatingimmediately,” says Lynn Matrisian, Ph.D., chair of Cancer Biology at Vanderbilt, whereasexperimental drugs traditionally are tested first in patients with advanced disease.

What’s needed is the development of smaller clinical trials looking at earlier stagesof disease, says Harold L. Moses, M.D., founding director of the Vanderbilt-IngramCancer Center. The studies should measure biological markers or “correlates” of drugactivity, and be flexible enough to change course quickly if it becomes apparent thatthe drug is most effective in a subgroup of research subjects.

“The idea is to do it better, more quickly and with less expense,” says Moses, currentpresident of the Association of American Cancer Institutes.

This fall, the Association of American Cancer Institutes, in partnership with theAmerican Association of Cancer Research and the American Society of ClinicalOncology, hosted a workshop on “designing a smart clinical trials system for the 21stCentury.” Attendees included representatives of the pharmaceutical industry, patientadvocacy groups and the research community.

In the past, “there’s been a lack of communication between the clinicians and thebasic scientists,” Matrisian explains. “We’re looking for new and better ways to makethis happen.”

– BILL SNYDER

the war onCANCERA STATUS REPORT

Above: Lynn Matrisian, Ph.D., (right) watchesBarbara Fingleton, Ph.D., perform surgery ona mouse used in cancer research.

Photo by Dana Johnson

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IMPROBABLE BEGINNINGS

By Lisa A. DuBois

Sir John Vane and the value of blue-sky thinking

Sometimes great discoveries

emerge slowly, after decades

of trials and errors. At other

times, ingenious ideas seem

to strike from out of the blue.

Such was the case with the

Nobel Prize-winning findings

by the late Sir John Vane, who –

over the course of a weekend –

cracked a 70-year-old mystery

about how aspirin relieves

pain and inflammation.

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Pictured left, clockwise from top right:

John Vane in his office at the

Wellcome Research Laboratories in

Beckenham, southeast of London,

and (center photo) in his Wellcome

lab – early 1980s.

Vane with longtime colleague

Professor Gustav Born at The

Royal Society in London. Like

Vane, Born is a Fellow of The Royal

Society, the United Kingdom's

national academy of science.

Colleagues gather outside Vane’s

office in Beckenham, mid-1970s.

Back row, second through fourth:

Philip Needleman, Ph.D., credited

with the development of Celebrex;

John C. McGiff, M.D., chair of

Pharmacology, New York Medical

College; and Miles Weatherall, Ph.D.,

Wellcome Research Laboratories.

Front row, left, Sergio Ferreira,

Ph.D., whose research helped

lead to the development of ACE

inhibitor drugs to treat high blood

pressure; and – third from left,

next to Vane – Professor Harold

Burn, Vane’s mentor from Oxford.

Photos courtesy of Professor Rod

Flower FRS and The William Harvey

Research Institute

Vane’s discovery was the “tipping point,” the cul-mination of knowledge and technique that led to animmediate explosion in the field of pharmacology, aswell as to some of the most exciting medical researchgoing on today. It also proved the value of serendipityand “blue sky” thinking in biomedical research.

“He had an uncanny nose for going after the right kind of scientificproblem,” says Philip Needleman, Ph.D., who helped pioneer the current generationof pain relievers. Needleman was one of the first Americans to study under Vane,who died last month from complications following a fall.

Vane’s entry into science began humbly enough. Born in 1927, the son of abusinessman who ran a small company making portable buildings, Vane grewup on the outskirts of Birmingham, England. Even in his early childhood hewas intrigued by experimentation, and at the age of 12 his parents gave him ajunior chemistry set for Christmas.

The gift was not without its costs in terms of a learning curve. One ofVane’s early experiments (involving a makeshift Bunsen burner attached to hismother’s gas stove) exploded, splattering hydrogen sulfide all over the kitchenwalls. Shortly thereafter, his father built a shed in the back yard – a suitabledistance from the house and complete with gas and water – for young John touse as a laboratory.

Vane eventually went on to the University of Birmingham where he developedan extreme distaste for chemistry. By the time he graduated he realized that itwas scientific discovery through experimentation that thrilled him, not academicexercises in theory. As a result he jumped when an opportunity arose for him tostudy pharmacology at Oxford – even though he had absolutely no biologicaltraining at the time. He was hungry to return to the laboratory bench.

As a doctoral student at Oxford in the 1950s, Vane learned to use bioassays,which detect and measure the natural sensitivity of pieces of tissue to hormonesand other biologically active compounds. At that time, the instruments forbioassay were highly complicated and answers to research questions came onlyafter weeks of laborious tests.

Vane, who in those early days was studying the biological activity of snakevenom, quickly grew impatient with the cumbersome biomedical technology nec-essary for his research. He was determined to find a way to reach answers morequickly, in particular, to find an easier method for examining unstable compounds.

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working in the lab – such as the next bestdose to try on that tissue sample.

Flower recalls, “As young techniciansand graduate students we used to apearound behind the camera, suddenlyswitching to a more serious demeanor aswe moved into its perceived field of view.”

About this time, investigators inLondon and elsewhere were making significant strides into understandingprostaglandin biology.

Prostaglandins are lipid moleculesfound in virtually all tissues and organs,which have powerful physiological effects.Often produced in response to trauma,stress or disease, these so-called mediatorscan affect smooth muscle activity, forexample, in blood vessel walls and theuterus, and they play a role in a host ofother metabolic processes.

Scientists at the time knew thatprostaglandins were useful in obstetrics for both inducing labor and terminating pregnancies, and that the compounds couldinhibit ulcer formation in the stomach andcause fever and inflammation in animals.Some of the most interesting prostaglandinswere notoriously difficult to study, however,because they are potent for only a few sec-onds before they are rendered inactive andexcreted. Even after four decades of research,the specifics of prostaglandin activity hadyet to be worked out.

By the mid-1960s, some of those ques-tions were being answered. Sune Bergstromof the Karolinska Institute in Stockholmhad purified the first prostaglandins anddetermined their structure, and his studentBengt Samuelsson was examining the variouscomponents within this newly discoveredbiological system.

One weekend in 1971, Vane had aremarkable idea. He knew that aspirin,one of the world’s most widely used drugs,reduced pain and relieved fever and

In 1956, after moving into a juniorfaculty position in ExperimentalPharmacology at the University ofLondon’s Royal College of Surgeons, hedeveloped a groundbreaking technique,the “cascade superfusion bioassay,” whichallowed him to investigate the release ofhormones and other substances in thebloodstream in “real time.”

Says Needleman, currently associate deanfor special research projects at WashingtonUniversity Medical School in St. Louis:“Vane’s methodology was a perfection ofexisting biological bioassay methods andwas so spectacular that it allowed us to askbiological questions with some specificityand get instant gratification. It requiredthe interplay of using different respondingtissues that could recognize different bodychemicals, and play them off against knownbioactive compounds.”

“At the time, this was a revolutionarytechnique of enormous sensitivity and versa-tility,” explains Rod Flower, Ph.D., a formerprotégé and longtime colleague of Vane’s,and professor of biochemical pharmacologyat the William Harvey Research Institute inLondon. “John had used this idea to measurethe release and disappearance of hormones inthe circulation and also to measure therelease of substances from other perfusedorgans, such as the perfused lung.”

From the moment of its invention,Vane thoroughly enjoyed the quick rewardhis bioassay provided. In fact, many timeshis lab members could find out the resultsof their endeavors in a single day. Flowerrecalls that at one point Vane installed aclosed circuit television camera in the labwith the lens aimed at the chart recorder,and he would watch the monitor from hisoffice. As the pen moved over the chartand the tissue began to contract, Vanewould phone from his command centerand reel off instructions to the people

inflammation – although no one understoodexactly how. Vane hypothesized that aspirinmight work by inhibiting the generationof prostaglandins – and he realized hecould easily test his theory by using hiscascade superfusion assay.

“It was a brilliant experiment. Itimmediately gave us a conceptual frame-work by which to evaluate the role ofprostaglandins in inflammation,” says JohnOates, M.D., an internationally knownprostaglandin researcher at VanderbiltUniversity Medical Center. “We could use his assay as a tool for identifyingprostaglandin activity in any number ofprocesses,” Oates says. “It linkedprostaglandins to fever and analgesia.”

Also, Vane’s work laid the cornerstonefor three decades’ worth of new directions inresearch, including the current focus on therole of cyclooxygenase (COX) enzymes. Todayresearchers are looking at evidence thatsuch nonsteroidal anti-inflammatory drugs(NSAIDs) as aspirin, Advil and Motrin thatblock COX activity might reduce the riskfor some kinds of cancers and for Alzheimer’sand other diseases. “None of this wouldhave made sense without Vane’s earlyexperiments on prostaglandins,” Oates says.

A year after his findings were pub-lished, Vane left academia for industry,accepting a position at the British phar-maceutical company, the WellcomeFoundation, and bringing a number ofoutstanding colleagues with him.Needless to say, Vane caught tremendousflak from his academic colleagues for hisdecision, but he remained undeterred.

During his 13 years at Wellcome,Vane was in on the development of manynew products, including prostacyclin, aprostaglandin derivative important in car-diovascular medicine because of its actionin dilating constricted blood vessels andinhibiting platelet aggregation, or blood

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clots. Vane engineered a collaborationbetween Wellcome and its competitorUpjohn to introduce prostacyclin into themedical marketplace.

Needleman says, “He was driven. Andit was quite natural for anyone working inprostaglandins, whose research was strongenough, to be in direct competition withJohn Vane. A lot of people melted.”

To many of his colleagues and students,however, Vane’s competitive spirit andverve was invigorating. “John had a lively,productive lab,” Oates says. “He drewaround him a remarkably talented andenergetic group of fellows.”

When dealing with young investigators,Vane gladly shared his scientific credo:“Always do the simple experiment first!”Flower says, “He was a master of theclever, low-tech, high-thought experimentthat involved nothing more complicatedthan a small strip of artery or similar tissuemoving a lever or transducer.”

Needleman adds, “John Vane was likea symphony conductor. He was a great scientific strategist. The week I spent withhim in 1972, I learned the bioassay methodsvery quickly, then we spent day and nighttalking about strategy.”

While Vane was fiercely loyal to thosewho worked for and with him, he wasnever one to suffer fools gladly. With a bigbooming voice and all the confidence of aBritish aristocrat (although he was raised in a decidedly middle class family), Vanecould command attention long before hebecame renowned for his research.

Needleman recalls one internationalpharmacology meeting in Switzerland in1969. In keeping with the free-spirit atti-tudes of that era, the meeting organizersplanned to allow a free-flow of ideas in thelarge amphitheater – an open, unstructureddiscussion among the hundreds of attendees.

Unfortunately, this was a disastrous

idea. “It was bedlam,” Needleman recalls.“Everyone was talking at once, nobodyhad the floor. Suddenly John Vane stoodup and in this wonderful English baritoneannounced, ‘I have a question!’ Everyonestopped talking to hear his question. Vaneasked, ‘WOULD YOU PLEASE PAUSELONG ENOUGH SO THAT I CANLEAVE THIS MEETING?’”

At that point, Vane turned on hisheels and headed for the exit. The othersin the audience applauded and followedhim out the door.

In 1982, Vane, Bengt and Samuelssonshared the Nobel Prize for medicine fortheir discoveries in prostaglandin synthesis.Oates finagled his schedule and attendedthe ceremony in Stockholm, Sweden, witha group of his international associates,cheering on their Nobel Prize-winningprostaglandin cronies. It was, he says, oneheck of a party.

In 1986, Vane retired from the businessworld and devoted his energies towardspreserving and advancing scientificresearch. He recruited some of his old labbuddies to form The William HarveyResearch Institute, an organizationdesigned to bridge the gap between aca-demics and industry.

In 1990, Flower, who had spent severalyears as chairman of Pharmacology at theUniversity of Bath, joined the Institute, thistime on equal footing with his belovedmentor as a member of the board of directors.The purpose of the institute, an affiliate ofthe United Kingdom’s Association ofMedical Research Charities, has been toencourage creative approaches to basicresearch, present new data and foster colle-giality among medical scientists.

For all of his accomplishments, Vane’sgreatest legacy may be the people he trained.

Flower worked on understanding thebiology of such autoimmune inflammatorydiseases as rheumatoid arthritis and asthma.Sergio Ferreira, Ph.D., professor of MedicalBiochemistry at the Federal University of Rio de Janeiro, is internationallyrenowned for his contributions to the collection of ACE inhibitor drugs for lowering blood pressure. John Hughes,Ph.D., shared the prestigious LaskerAward in 1978 for the discovery ofendogenous opioid peptides involved inthe body’s regulation of pain.

Salvador Moncada, Ph.D., currentlydirector of the Wolfson Institute forBiomedical Research of the UniversityCollege London, pioneered research into nitricoxide, now considered a “super-molecule”because of the role it plays in the immuneand nervous systems, in inflammation and

in programmed cell death (apoptosis). Needleman went on to hold executive

positions in the pharmaceutical giants,Pharmacia, Monsanto and Searle, and wasinvolved in the development of such drugsas the COX-2 inhibitors Celebrex, Bextraand Dynastat, and Inspra, a blood pressuredrug that blocks the actions of the hor-mone aldosterone.

Needleman says, “The years I scientif-ically jousted with John Vane more thanprepared me for a career in industry whereI would be dealing with CEOs, boards ofdirectors and industry analysts. To survivea scientific interaction with John Vane youhad to be at the top of your game. He wasa great influence.”

Throughout his career, Vane was,first and foremost, an activist for scien-tific freedom.

Recalling his days in training, Flowersays, “John’s attitude to drug discoverywas that if you gave bright scientists(creative freedom) then they would comeup with the goods sooner or later. We hadfew formal departmental meetings ordepartmental seminars, and yet somehowwe seemed to know more about what wewere individually doing, and what ourcolleagues out there were doing, than atany other time.

“Despite these factors, which no doubtwould horrify a head of department today,the department was undoubtedly thefriendliest, the fairest, and the safest Ihave ever worked in.”

Vane echoed this point of view in his speech at the 1982 Nobel banquet –expressing ideas that still resonate 22years later: “The medicines of today,” hesaid, “are based upon thousands of years ofknowledge accumulated from folklore,serendipity and scientific discovery. Thenew medicines of tomorrow will be basedon the discoveries that are being madenow, arising from basic research in labora-tories around the world ...

“In many countries now, research inuniversities is under severe financial restraint.This is a shortsighted policy. Ways have tobe found to maintain university researchuntrammeled by requirements of forecastingapplication or usefulness. Those who wishto study the sex-life of butterflies, or theactivities associated with snake venom orseminal fluid should be encouraged to do so.It is such improbable beginnings that leadby convoluted pathways to new conceptsand then, perhaps some 20 years later, tonew types of drugs.” LENS

Pictured here: (Far left) In his office inBeckenham in the mid-1970s, John Vanevisits with long-time friend and colleagueProfessor Ryszard J. Gryglewski ofJagiellionian University Medical College inCracow, Poland. (Left) Vane in his lab at theRoyal College of Surgeons in the 1960s.

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Inflammation and the

development of heart

disease

BY HAROLD OLIVEY

When it comes to heart disease, fat in the bloodstream

is one of the major culprits. Yet as many as 50 percent

of people with atherosclerosis – artery blockage that

can lead to a heart attack – do not display traditional

risk factors such as high cholesterol.

Thanks to recent technological advances, scientists

are now able to take a closer look at what stubbornly

remains the nation’s leading disease killer. What they

are finding may surprise you.

Inflammation, incited by a plethora of infection-fighting

and wound-healing blood cells and molecules, seems

to play a major role in atherosclerosis. For example,

high levels of C-reactive protein (CRP), a circulating

marker of inflammation, are associated with an

increased risk for heart attack and stroke.

That doesn’t mean a once-a-day anti-inflammatory pill

to prevent heart disease is right around the corner.

Researchers are hopeful, however, that their pursuit of

inflammation may lead to better ways of treating and

preventing heart disease and other ailments of the

Western lifestyle – including type 2 diabetes.

THAT HURTS

THE

Pictured left: MacRae Linton, M.D., andSergio Fazio, M.D., Ph.D., surrounded byimages of cholesterol-engorged “foamcells,” have found tantalizing molecular andcellular clues supporting a link betweeninflammation, heart disease and metabolicsyndrome.

Photo illustration by Dean Dixon

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The Vanderbilt connectionVanderbilt’s contributions to the field

of inflammation and heart disease beganmore than a decade ago, when, as a residentphysician, MacRae Linton, M.D., becameinterested in atherosclerosis. “I would seeall these people having bypass surgery, andnobody was thinking about their risk fac-tors,” recalls Linton, now professor ofMedicine and Pharmacology at Vanderbilt.

Linton’s interest led him to pursue anendocrinology fellowship at the renownedGladstone Institute of CardiovascularDisease at the University of California, SanFrancisco. There he met Sergio Fazio, M.D.,Ph.D., another research fellow who wasstudying how the body handles cholesterol.

“The real excitement came fromunderstanding the complexity of lipidmetabolism,” recalls Fazio, an Italiannative whose doctorate is in MolecularBiology. “But when you look at it fromthe point of view of clinical relevance,what’s important is the damage that lipidmetabolism can do to the vessel wall. Itwas clear that we needed to become vascu-lar biologists.”

Linton and Fazio decided early in theircareers to take a team approach to theirresearch. Since joining the faculty atVanderbilt in 1993 (Fazio is a professor ofMedicine and Pathology), they have pub-lished several seminal papers in the field ofatherosclerosis, and they co-direct the med-ical center’s Atherosclerosis Research Unit.

In one of their highest profile papers,published in the journal Science in 1995,Fazio, Linton and James Atkinson, M.D.,Ph.D., professor of Pathology, reported thatapolipoprotein E (apoE), a protein importantin lipoprotein metabolism, seemed to pro-tect mice from developing atherosclerosis.

The largest supply of apoE comes fromthe liver, Linton says. But the protein isalso made by macrophages, and thus mayparticipate in the inflammatory response.

To determine what, if any, role apoEexpressed in macrophages played in thedevelopment of atherosclerosis, Linton andFazio studied a strain of mice that lackedboth copies of the apoE gene. These micedevelop significant atherosclerosis, unliketheir genetically normal – or wild type –counterparts. The researchers irradiatedthe apoE deficient mice to kill their bonemarrow, the source of macrophages, thengave them transplants of bone marrowcells from wild type mice.

Mice deficient in apoE that receivedthe transplants did not develop atheroscle-rotic plaques. “The small amount of apoEthat came from the bone marrow wasenough to cure the mice,” says Linton.

After the study published in Science,“we became more interested in genes relatedto cholesterol homeostasis – enzymes, pro-teins, receptors,” he continues. “Recentlywe’ve expanded that into an interest ininflammation and how macrophages andother cells may play a role in the inflamma-tory process of atherosclerosis.”

“Living wounds” that will not healAtherosclerotic plaques form when

blood vessels are injured by chemicals (suchas those found in cigarette smoke), highblood pressure or high levels of plasmalipids (fats, like cholesterol).

These plaques are living wounds thatcan trigger clot formation inside the bloodvessel. When a clot forms in an artery thatsupplies the heart with blood, a heartattack ensues, leading to death of heartmuscle. Understanding the cellular and

molecular events that lead to atherosclerosiswill be critical to making progress againstthe disease.

Atherosclerotic plaques contain a vari-ety of cell types. These include endothelialcells that line the blood vessels and makeup the endothelium, and vascular smoothmuscle cells that give form and resilienceto the blood vessels. Other cells found in plaques, such as pro-inflammatorymacrophages and lymphocytes, do notnormally reside in the vessel wall. Instead,they remain in the bloodstream and standready to mediate inflammatory responsesat sites of injury and infection.

As part of the innate immune responsesystem, macrophages are among the first lineof defense at sites of injury. Derived fromcirculating monocytes, these specialized cellsengulf and destroy pathogenic organismsand damaged cells. When circulating mono-cytes encounter injured endothelium, theymigrate underneath the endothelium. Thisinvasion of monocytes starts the formation ofthe atherosclerotic plaque.

Once inside the vessel wall, monocytesdifferentiate into macrophages that become“activated” and recruit other monocytesand T helper lymphocytes to enter theplaque. They also ingest cholesterol. Asmacrophages become engorged with cholesterol, they take on a characteristicallyfoamy appearance, and thus are referred toas “foam cells.”

As an atherosclerotic lesion becomesmore advanced, an increasing number offoam cells are found in the plaque due tothe continual recruitment of macrophagesinto the lesion. A thin fibrous cap ofsmooth muscle cells and collagen formsover the plaque, and smooth muscle cellsunderlying the damaged endothelium

Colorized microscopic image shows monocytes “diving” into an ather-osclerotic lesion in the lining of a blood vessel. The monocytes havebeen “activated” by inflammatory signals on the blood vessel lining.Arm-like pseudopods drag the monocytes into the gaps betweenendothelial cells and down into the atherosclerotic plaque beneaththe endothelium. Here they become macrophages, vacuum up excesslipid and add to the size of the plaque.

Image courtesy of Jay Jerome, Ph.D., director of the Research ElectronMicroscopy Resource at Vanderbilt; colorization by Deborah Doyle

(continued on page 26)

A 70-year-old diagnostictest has become the latesttool for predicting a person’sfuture risk of developing cardiovascular disease. Itmeasures levels of C-reactiveprotein (CRP), which is madeby the liver during periods of inflammatory activity in the body.

Atherosclerosis is thoughtto raise the plasma levels ofCRP as any other inflammatoryprocess would. Until recently,however, the relatively smallincrease in CRP resultingfrom vessel disease wasbelow the detection range ofthe standard test method.

A method was developed in the late 1990s to increasethe sensitivity of the CRPassay. This new diagnostictool, called the high-sensitivityCRP test (hsCRP), has becomea recommended standard forthe care of individuals at risk for developing coronaryartery disease.

Cardiologist Paul Ridker,M.D., Eugene BraunwaldProfessor of Medicine atHarvard University, helpeddevelop the hsCRP test andhas been its main champion.

Ridker and his colleaguesmeasured CRP levels in blood

samples from a subset of par-ticipants in the Physicians’Health Study, which assessedthe benefits of aspirin andbeta-carotene in reducing therisk of adverse cardiovascularevents in several thousandmale physicians. They foundthat participants with elevatedCRP, as detected by thehsCRP assay, were atincreased risk for heartattack and stroke.

Intriguingly, the elevatedrisk was independent of otherknown risk factors like highblood levels of low-densitylipoprotein (LDL) cholesteroland smoking. Subsequentstudies have largely support-ed this finding.

Last year the AmericanHeart Association and U.S.Centers for Disease Controland Prevention (CDC) pub-lished a scientific statementsuggesting that physicianscould reasonably test for CRPin patients considered to be atmoderate risk for developingcardiovascular disease.

More recently, however,researchers led by John Danesh,M.B., Ch.B., of CambridgeUniversity performed a meta-analysis of prospective studiesof coronary artery disease, and

found that CRP concentration“added only marginally” to thepredictive value of establishedrisk factors like smoking andserum LDL concentration.

“Recent recommendationsregarding the use of measure-ments of C-reactive protein in the prediction of coronaryheart disease may need to be reviewed,” the researchersreported in April in The NewEngland Journal of Medicine.

Sergio Fazio, M.D., Ph.D.,professor of Medicine andPathology at VanderbiltUniversity Medical Center, doesnot believe that current dataconclusively support a causallink between CRP and athero-sclerosis. In comparison, LDLcholesterol is both a circulatingmarker and causative agentof atherosclerosis. CRP is,however, the best of severaldiagnostic tools available todetect inflammation, a recognized component of atherosclerosis, he says.

CRP also may be useful inthe diagnosis of metabolicsyndrome, a clustering of riskfactors related to insulinresistance that is recognizedas a predictor of future riskfor developing cardiovasculardisease and diabetes.

People diagnosed withmetabolic syndrome possessat least three of the followingconditions: elevated serumtriglycerides (TG), low levelsof high-density lipoprotein(HDL, often called the “good”cholesterol), visceral obesity,elevated blood pressure, andinsulin resistance or glucoseintolerance (see table).

Obesity may help tie inflammation to heart diseaseand diabetes.

Adipose (fat) tissue releasespro-inflammatory cytokinessuch as interleukin-6 (IL-6),which may contribute to thedevelopment of atherosclerosisand heart disease. IL-6 alsomay interfere with the body’sability to respond to insulin, ahormone that regulates glucosemetabolism. Resistance toinsulin signaling is a hallmarkof metabolic syndrome, andcan eventually lead to type 2 diabetes.

“As a relatively specificmarker of inflammation, (CRP)does help identify people” atelevated risk of cardiovasculardisease, says Doug Vaughan,M.D., chief of the Division of Cardiovascular Medicine at Vanderbilt.

“It helps you change yourperceptions about a givenpatient and perhaps move themfrom a moderate risk categoryto a higher risk category. Andthat in turn precipitates amore aggressive interventionto reduce risk. That’s thevalue of it.” LENS

C Reactive Protein: The Next Big Thing? by Harold Olivey

Hallmarks of Metabolic Syndrome RISK FACTOR VALUE IN MEN VALUE IN WOMEN

Fasting blood triglycerides 150 mg/dl 150 mg/dl

Low blood HDL cholesterol <40 mg/dl < 50 mg/dl

Central obesity (waist circumference) >40 inches >35 inches

High blood pressure >130/85 mmHg >130/85 mmHg

Fasting blood glucose >110 mg/dl >110 mg/dl

Source: American Heart Association –www.americanheart.org.

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begin to proliferate, expanding the volumeof the plaque.

Stable atherosclerotic plaques are lesslikely to cause an acute cardiovascular eventsuch as a heart attack or stroke. Althoughthey restrict blood flow through the lumenof the blood vessel, they rarely cause totalocclusion. Instead, plaques provide a sitewithin the vessels where clots can form.Platelets, blood cells involved in clotting,do not attach to the wall of healthy bloodvessels. However, they will attach to ath-erosclerotic lesions.

As foam cells within a lesion die, thecenter of the plaque becomes necrotic,weakening the overlying fibrous cap andincreasing the risk of rupture. The interiorof an atherosclerotic plaque contains mole-cules that attract platelets and provideample sites for attachment.

Thus, when an atherosclerotic plaqueruptures, a clot can quickly form and completely occlude the blood vessel. Acutecardiovascular events are most often precip-

itated by the rupture of the thin fibrous capthat covers the atherosclerotic plaque.

Clot blocker Aspirin, the classic anti-inflammatory

drug, can prevent clot formation over atherosclerotic plaques by inhibiting theenzyme cycoloxygenase-1 (COX-1) inplatelets. That, in turn, reduces formationof a powerful, pro-coagulant prostaglandincalled thromboxane A2.

Aspirin also inhibits the relatedCOX-2 enzyme, which produces otherpro-inflammatory prostaglandins at sitesof inflammation. Long recognized for itsrole in chronic inflammatory processes likearthritis, COX-2 is also expressed by cellswithin atherosclerotic plaques, but notelsewhere in the circulatory system.

Linton and Fazio recently havereported that COX-2 contributes to thepathology of atherosclerosis in mousemodels of the disease. Inhibiting theenzyme in mice with high cholesterol levels,

either pharmacologically or genetically,retards early atherosclerotic plaque forma-tion. These data suggest that blockinginflammation could suppress the progressionof atherosclerosis.

But Linton cautions that the tale is notso cut-and-dry. “It’s tough to say (whetherCOX-2) is just good or bad. It probablydepends on which cell is expressing it andat what time.” For example, “COX-2 isexpressed by basically all the players in theartery wall – smooth muscle cells, endothe-lial cells, macrophages,” he says.

In addition, macrophages down-regulate their pro-inflammatory activitiesand lose COX-2 expression when theybecome foam cells. Other studies havesuggested that blocking COX-2 activitydoes little to ameliorate the symptoms of more advanced atherosclerotic lesions.

This change in macrophage geneexpression may come out of necessity:“When it’s overloaded with cholesterol,the macrophage has to focus on getting

Endothelium that is injured, in this case by high levels of low-density lipoprotein (LDL) cholesterol, releases factors thatattract blood cells called monocytes. Once inside the tissue, themonocytes differentiate into macrophages. Part of their job is tosweep up excess cholesterol. As they become engorged withcholesterol, the macrophages take on a foamy appearance, andnow are called foam cells.

Interactions between foam cells and white blood cells trigger achronic inflammatory process. Smooth muscle cells migrate tothe arterial wall, proliferate and secrete proteins that form afibrous plaque. As the foam cells die, the plaque weakens andcan rupture. Platelets are attracted to the site of the rupture,and can quickly form a clot that blocks the vessel completely.

A. B.

Tale of a thrombusILLUSTRATIONS BY DOMINIC DOYLE

“I wouldn’t be surprised if we develop a panel of20 to 30 genes that we routinely look at … todefine and predict risk.” DOUG VAUGHAN, M.D.

(continued from page 24)

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Cardiovascular disease, like cancer, is a health problem best treated with preventionand early detection. Physicians successfully identify many at-risk patients by measuringthe blood levels of markers like LDL cholesterol. However, for many patients, their firstindication of cardiovascular disease is suffering a heart attack or stroke.

“The cornerstone of risk determination is found in the parameters that have beenmeasured and validated through prospective epidemiological studies,” says DougVaughan, M.D., the C. Sidney Burwell Professor of Medicine and chief of CardiovascularMedicine at Vanderbilt. “Those (studies) have really defined the power of factors such ashigh HDL, low LDL, hypertension and smoking as authentic determinants of risk over time.”

Yet an increasing number of patients develop cardiovascular disease in the absence ofthese traditional risk factors. “That has motivated and catalyzed a search for other impor-tant markers or determinants of risk,” he says.

One emerging risk factor, insulin resistance, increases cardiovascular disease risk with-out significantly impacting lipid levels. “Generally, people with insulin resistance don’thave high LDL; they’ve got a low HDL, they’ve got high TG,” Vaughan says. Finding thelink between insulin resistance and heart disease, therefore, is critically important.

One possibility: a serum protein involved in clot formation called plasminogen activatorinhibitor-1 (PAI-1). “The neat thing about PAI-1 is that it is driven by so many different fac-tors that contribute to cardiovascular disease in the 21st Century,” Vaughan says, includinginflammation and insulin resistance. PAI-1 levels track with CRP, making PAI-1 an “integrativemarker of multi-factorial inputs that might influence your (heart disease) risk,” he says.

Vaughan’s laboratory has published several papers describing how the PAI-1 gene isregulated. When the PAI-1 gene becomes “switched on,” the result is higher plasma lev-els of PAI-1 protein. Recent reports from Vaughan’s laboratory have identified ways inwhich the PAI-1 gene might be switched on by inflammation. Others have reported thatdrugs designed to combat insulin resistance decrease circulating levels of PAI-1. “If youimprove the lipid profile and if you reduce insulin resistance in patients,” he says, “youwould predict that their PAI-1 levels are going to come down.”

Meanwhile, new technologies such as cardiac magnetic resonance imaging (MRI) andmulti-slice computed tomography (CT), offer the promise of non-invasive, real-time diagno-sis of coronary artery disease – at an earlier stage than ever before. Coupled with analy-sis of circulating markers of heart disease, perhaps even more patients can be sparedthe pain, expense, and morbidity of a heart attack or stroke.

– HAROLD OL IVEY

rid of cholesterol,” Linton explains. “Beforethat, it may be more important to be aninflammatory cell involved in the recruit-ment of other cells and propagation of theinflammatory pathway.”

Experiments on atherosclerotic micehave provided significant insight into themechanisms behind cardiovascular disease,including the recent findings on the roleof inflammation. Even so, Fazio is quickto point out that the mouse models of ath-erosclerosis offer only a pale reflection ofthe disease state in human beings.

“There is an issue in quality and in theextent and topography (of lesions in mice),”Fazio cautions. The majority of humancases of atherosclerosis, according to Fazio,are due to a combination of risk factors.This is in sharp contrast to atherosclerosisin mice induced experimentally by the tar-geted disruption of one or two genes.

Talking back to fatDuring the past decade, two new

classes of drugs were developed to relievepain and inflammation in patients withrheumatoid arthritis – specific inhibitorsof the COX-2 enzyme, and blockers of thepro-inflammatory tumor necrosis factor(TNF). It remains to be seen, however,whether they also will be useful in pre-venting heart disease.

Although COX-2 is expressed in atherosclerotic lesions, chronic use of highdoses of one of the COX-2 inhibitors hasbeen linked to an increase in blood pressure,edema and serious heart problems in somepatients. As for TNF-inhibitors, animalstudies and at least one report in a patientsuggest that TNF blockade may actuallydestabilize atherosclerotic plaques and precipitate heart attacks.

Statins, the blockbuster cholesterol-lowering drugs, also have anti-oxidant and anti-inflammatory properties that may protect against cardiovascular disease.To test this hypothesis, investigators inthe multi-center JUPITER study areadministering the statin drug Crestor toparticipants who have elevated circulatinginflammatory markers including CRP, but normal LDL and triglyceride levels.The study is expected to be completed inabout three years.

The newest targets for pharmacologicaltreatment of atherosclerosis may come fromstudies of how adipose tissue (fat) regulatescholesterol metabolism and inflammation.Fazio and Linton point to recent studiesthat suggest adipose tissue, composed of fatcells, and macrophages in atheroscleroticplaques lead the inflammatory response inatherosclerosis and cardiovascular disease.

Some genes originally reported to beexpressed primarily or exclusively in adiposetissue are also expressed in activatedmacrophages. Some of these genes, includingthe fatty acid binding protein aP2, arebelieved to be involved in insulin resistance,an early hallmark of type II (non-insulindependent) diabetes. These recent reportssuggest inflammation as a critical linkbetween diabetes and atherosclerosis.

Individuals showing symptoms ofinsulin resistance are more likely to developcardiovascular disease as well as diabetes.Patients with diagnosed diabetes are at elevated risk for adverse cardiovascularevents such as heart attack and stroke. Bytargeting proteins expressed in fat cells andmacrophages that seem to play a dual rolein reducing insulin sensitivity and increasinginflammation, new therapies may reduce

the incidence of both atherosclerosis anddiabetes in at-risk populations.

“I wouldn’t be surprised if we developa panel of 20 to 30 genes that we routinelylook at in individuals to define and predictrisk,” says Doug Vaughan, M.D., chief ofCardiovascular Medicine at VanderbiltUniversity Medical Center. “It’s going to bea multi-factorial approach that includes …biochemical, physiological and geneticparameters.” LENS

An Ounce of Prevention: Emerging Tools in the Fight AgainstCardiovascular Disease

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TEAMWORK

H A R O L D VA R M U S , M . D .

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A conversation with Sir Ravinder Maini

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Is the current method of conducting clinical trials adequate fordetermining the impact of candidate drugs on a disease processlike rheumatoid arthritis?

A trial is by definition a very artificial entity in that you have exclusion andinclusion criteria, which define populations very rigidly. Some people wouldargue that defining patients before you enter them into a trial often means thatyou’re loading that trial in favor of the patients that are most likely to respond,or patients that are least likely to show side effects ...

Already the regulatory authorities are mandating so-called phase four studies.Once the drug is licensed, companies are still required by regulatory authoritiesto keep information about adverse events, for example. For expensive drugs, I thinkmore and more payers are insisting on some kind of evidence of effectiveness inthe real-life situation …

In a world where resources are limited and health budgets are under strain, …some kind of objective evidence that they are doing good and not harm is partand parcel of what I call post-marketing surveillance. That’s a different questionfrom whether you can have better trials. And the answer to that is yes.

Traditionally in most diseases you start off with patients that are the sickest, as was the case with anti-TNF drugs. It isn’t the best population to see the bestresult in, but these people are in a terrible mess usually by the time they get intothe trial because they’ve failed everything else, they’re often debilitated and sick as a result. Their resistance to infection is low because they’ve become immobile or they’ve put on weight – all the other factors that encourage what we call co-morbidity.

Obviously they are often not the best candidates to include in a trial. But ifyou have an agent of unknown safety, usually ethical issues demand that youstart to gain full consent from a patient population where it’s unlikely that

you’re going to do them harm. That’s adifficult question.

Can anti-TNF therapy reduce therisk of heart disease?

We have reason to believe that coro-nary artery disease is inflammatory innature, and that the inflammation in bloodvessels affected by atherosclerosis is a processthat is very similar to TNF-driven inflam-mation in other diseases. The prediction isthat anti-TNF treatment may be beneficialin patients with coronary artery diseasewho are not in heart failure.

Such trials haven’t yet been done, butit’s likely that we’ll get an answer from theregistries that have been created to followup patients on anti-TNF treatment ...

By the way, in rheumatoid arthritis,death from coronary artery disease isincreased significantly. So what we wouldexpect to see is that the population that isreceiving anti-TNF will normalize andbegin to resemble more the populationthat doesn’t have an increased coronaryartery disease.

What about cancer?It turns out that patients with rheuma-

toid arthritis have an increased incidence ofcancer of the lymphatic glands – lymphomas ...

In clinical trial evidence, there was(an) increased incidence of lymphatic cancercompared to the normal population. TheFDA actually looked at this last year andconcluded that the evidence at this stagewas insufficient to tell us whether the ratewas as expected in this disease because ofthe underlying disease, or whether therewas an effect of anti-TNF therapy on theincidence of lymphatic cancer. Once again,we can only hope that the registry will tellus the answer to that ...

As far as any other type of cancer isconcerned, epidemiological studies have notshown any increase in rheumatoid arthritispatients and so far no increase in any clinicaltrials or registry of any other kind of cancer.There is however some very interesting datain relation to COX inhibitors, which sug-gest that bowel cancer is reduced in patientsthat are taking regular NSAIDs …

The majority of patients with rheuma-toid arthritis or most inflammatory diseasesare on anti-inflammatory drugs anyway, andtherefore we would expect a reduction in

THE DEVELOPMENT OF ANTI-TNF THERAPY

Emeritus Professor Sir Ravinder Maini, M.D., and Professor Marc Feldmann,Ph.D., of Imperial College London’s Kennedy Institute of Rheumatology,received the 2003 Albert Lasker Award for Clinical Medical Research fortheir “discovery of anti-TNF (tumor necrosis factor) therapy as an effectivetreatment for rheumatoid arthritis and other autoimmune diseases.”

Maini, who was born in India and has lived in the United Kingdom for 50years, was knighted last year by Queen Elizabeth II for his groundbreakingwork. Recently, he shared his thoughts with Lens editor Bill Snyder aboutthe challenges of developing new treatments for inflammatory disorders,and the importance of collaboration.

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be seen in my view as a duty of academicenterprise because, after all, the wealth of anation depends in the end on how the brainsof the country use that information formaking progress. It is important that aca-demics don’t think we should be ashamedof enterprise. On the contrary, we shouldfeel pleased to see this happen, and help tomake it happen.

How does this square with the tradi-tional reluctance to mix academicand commercial activities?

The traditional academic view, whichhas tended to regard commercialism as anundesirable mammon, I don’t think actuallyrepresents a well-oiled, advanced nation’sway of working.

There is no doubt at all that Britainin the Victorian Age demonstrated howexploitation of inventions was a key part of the Industrial Revolution. That remainstrue for the molecular revolution today.

What is more important is the transparency and freedom of access toinformation – that’s of course absolutelyvital, that an academic should be able toshare and have access to information,reagents, and so on, so the process ofinvention and new discovery is not hin-dered, but rewarded.

It is a two-way street, and if managedproperly, a win-win situation. Unfortunately,real life sometimes intrudes on that.Selfishness and greed can sour these things,can’t they? But that shouldn’t by itself be a hindrance to progress.

We’re probably at a unique time in thehistory of biomedicine. The opportunitiesare absolutely fantastic, but the threats arethere. Progress … requires more than theindividual can ever contribute. It requiresan ordered society that is aware of itsresponsibilities. LENS

bowel cancer incidence in such people. Sothere is yet another confounding factor outthere – whether anti-TNF, which is knownto block COX-2 just as well as aspirin orNaprosyn or any of these kinds of agents,might have the same beneficial effect.

Is there a concern that some candi-date drugs may be abandonedbecause they do not show signifi-cance when evaluated independent-ly, even though they may be usefulin combination with other drugs?

That’s certainly true also for anti-rheumatic treatment. Even anti-TNF hasbeen shown to work best when used withmethotrexate, rather than as monotherapy.That’s now proven for all three anti-TNFdrugs. If we hadn’t done such trials, wewouldn’t know that. And it’s possible thereare other drug combinations with anti-TNF, which are going to be better thananti-TNF alone ...

How can we encourage more testingof products in combination?

Sadly, synergy between companies hasnot yet been a feature of drug development.Usually it means the academic communitywill do the clinical trial.

I must say I can’t see the logic of itbecause you would imagine that if twodrug companies thought there was arationale for a combination, that it wouldpresent a win-win situation for them to get together and do such a trial.

What’s holding them back?I think it’s usually competition fears,

the fear that the market share of their indi-vidual drug will suffer. I think that … isbeing reflected in the big takeovers ratherthan company collaboration …

When Pfizer takes over another company, or Wyeth merges with Amgen,basically what’s happening is that thepipeline of the two companies can then be combined ... But I don’t see why (collaboration) can’t happen between twoindependent companies.

According to some, the traditionalcareer path in academic sciencepresents another challenge to collaboration because researchersmust demonstrate their independenceto win research grants and publishtheir results. Do you agree?

Certainly there is some truth in it.The competitive grant system doesencourage individuals to build their ownlittle enterprise. And in that environment,sharing of knowledge is often regarded asa threat rather than as an opportunity. Ithink that it’s further encouraged by thefact that discoveries now have commercialvalue, because you can patent your discov-eries and exploit them.

But I do think that in practically every case that I can think of where majordiscoveries are made, either at the basic science level or at the clinical translationallevel, collaboration is more or less essential.Whether it was the Human GenomeProject, or at a minor level, taking anti-TNFfrom the bench to the clinic, collaborationwas essential.

What is usually needed is trust andenlightenment between the groups thatwill work together, and good managementof the process so that the reward system isfair ... I think that in good environments,that is beginning to happen ...

I think teamwork is beginning to beappreciated more as a necessity in scientificachievement. In a properly managed envi-ronment, the career progress of individualshas to be taken care of. The real contributorshave to be singled out ... I think that jour-nals, for example, are becoming much moretough about accreditation of authorship.And similarly, where intellectual propertyis created, people are much more aware ofand smarter about how that should betaken care of.

In one way, it’s making the whole thinga little more commercially driven, but Itake the view – rightly or wrongly – that inorder to progress, resources of commercialbacking are needed to take things fromrudimentary bench to the clinic anyway.That’s the reality. You can’t do it withoutsome involvement of commerce in it.

The whole business of technologytransfer from academia to industry should

“”

PROGRESS … REQUIRES MORE THAN THEINDIVIDUAL CAN EVER CONTRIBUTE. ITREQUIRES AN ORDERED SOCIETY THATIS AWARE OF ITS RESPONSIBILITIES.

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Teamwork among scientists at VanderbiltUniversity Medical Center during the past 35years has contributed much to current under-standing of the role of the cyclooxygenase(COX) enzymes and their products – theprostaglandins – in human disease.

Prostaglandins, which were first isolatedfrom the prostate gland in 1936, are veryrapidly metabolized, or broken down, making

measurement in the blood difficult.Researchers at Vanderbilt led by JohnOates, M.D., developed methods for meas-uring levels of prostaglandin metabolites(breakdown products) in the urine usingmass spectrometry.

Using this technique, the research team –which by the late 1970s included L. JacksonRoberts, M.D. – identified prostaglandin D2 asa product of the human mast cell and demon-strated its release during allergic asthma.

With colleagues including Garret A.FitzGerald, M.D., now chair of Pharmacologyat the University of Pennsylvania, Oates andRoberts showed that low doses of aspirin

blocked the production of thromboxane, aprostaglandin made by platelets that causesblood clotting and constriction of blood ves-sels. Their findings supported the use oflow dose aspirin to prevent heart attacks.

“All of this could not have been possiblewithout the early and ongoing commitment onthe part of Vanderbilt to mass spectrometry,”says Jason Morrow, M.D., F. Tremaine BillingsProfessor of Medicine and Pharmacology atVanderbilt. “John realized that in 1969 when(as director of the Division of ClinicalPharmacology) he brought the first massspectrometer to Vanderbilt,” Morrow says.

In the early 1990s, Vanderbilt researchersled by Ray DuBois, M.D., Ph.D., discovereda link between the COX-2 enzyme and coloncancer. That work helped lead to currenttests of COX-2 inhibitors as a potential wayto prevent cancer. Recently another groupled by Morrow and David H. Johnson, M.D.,director of the Hematology-Oncology divisionat Vanderbilt, reported that urine levels of aprostaglandin metabolite called PGE-M couldpredict the effectiveness of a COX-2inhibitor in patients with non-small cell lungcancer. This suggests, says Morrow, “thatthe measurement of these inflammatory‘mediators’ and their suppression may beuseful in the treatment of lung cancer.”

COX enzymes also may play a role in Alzheimer’s disease. In addition toprostaglandins, the COX pathway can leadto the production of highly reactive molecu-lar compounds called levuglandins, which, in turn, can form “adducts,” or irreversibleattachments to proteins that may be toxic to nerve cells.

In July, Oates and his colleagues atVanderbilt and Johns Hopkins Universityreported that they found a 12-fold increasein the level of adducts in the brains ofpatients who had Alzheimer’s disease com-pared to age-matched control brains.

“These are the first clear data showingthat COX products are elevated in the brainsof patients with Alzheimer’s disease,” saysOates, Thomas F. Frist Professor ofMedicine and professor of Pharmacology.

Vanderbilt currently is participating in a national trial to see if long-term use ofCOX inhibitors will reduce the incidence ofthe disease.

– BILL SNYDER

Breaking theCOX codeUsing the team approach

Ray DuBois, M.D., Ph.D.Photo by Dean Dixon

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My body’s immune system has devastated thelinings of my joints. It’s like the tornado that cut aswath through our farm property this spring, top-pling two pecan trees, a catalpa that had been in fullbloom, and an American Beech that was 100-plusyears old.

Like the tornado, rheumatoid arthritis caughtme by surprise. But unlike damage from winds thatcan occur in seconds, this insidious disease workedon me for a while before I – or my doctors – realizedwhat was happening.

In March of 2000 I was struck by an incrediblefatigue. Outdoor activities I’d previously savoredafter my workdays in a windowless school librarybecame impossible. Malaise and depression followed.I felt so miserable I did not even want to tell mydoctor, fearing age to be the culprit. Eventually I lethim know and I was treated for depression.

By August, my right hand had become sopainful that even simple tasks like assigning textsbecame unbearably painful. I thought that I had over-compensated for my left hand, which had fractured.

But the pain and fatigue continued evenafter my left hand healed. I took a leave ofabsence and later resigned.

By the summer of 2002, my handswere waking me during the night withnumbness and tingling sensations. Anorthopedic surgeon diagnosed carpal tun-nel syndrome in my right hand. It tooktwo operations to relieve the pain. Myphysical therapist noted that both handshad stiffness, but because there was norheumatoid arthritis in my family, Iignored his advice to see a rheumatologist.

In the summer of 2003, I began tolimp from pain and swelling in my ankles.I had trouble rising from a seated positionand getting in and out of a car. I wouldtake shelter under a tornado warning, butuntil my inflamed ankles literally broughtme to my knees with pain I was in denial.

Finally, I listened to my therapist andasked my doctor to refer me to a rheuma-tologist. In January 2004, Dr. Victor Byrdat Vanderbilt pulled my classic symptomstogether into a diagnosis and treatmentprogram for rheumatoid arthritis.

The medications are harsh on one’ssystem and take a while to provide relief,but I am managing better. My pain hasalmost disappeared, and I am currentlyparticipating six days a week in a circuitworkout to keep my joints flexible and tostrengthen my bones. I have not had anyenergy, though, and still have to nap eachafternoon to keep going at all.

The most aggravating damage is tomy ankles. Losing weight will hopefullytake some of the stress off these joints, sothat is a goal I’m working on right now. Iam very grateful that I finally have beendiagnosed, and that I was able to spend 54years without this pain and stiffness.

Be informed. Arthritis is the leadingcause of disability in people over the ageof 15. Read your body’s warnings beforerheumatoid arthritis or some other diseasedoes irreparable damage. LENS

Toni Locke is a former school librarian wholives in Fayetteville, Tenn.

Pictured here: Toni Locke on thefamily farm in Fayetteville, Tenn. Beyond the pond – one of thelarge trees toppled by a recenttornado.

Photography by Anne Rayner

Living in the wake of rheumatoid arthritis

By Toni Locke

A tornado inthe body

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Jeffrey R. Balser, M.D., Ph.D.Anesthesiology, PharmacologyAssociate Vice Chancellor for Research

Gordon R. Bernard, M.D.MedicineAssistant Vice Chancellor for Research

Randy D. Blakely, Ph.D.PharmacologyDirector, Center for Molecular Neuroscience

Peter Buerhaus, Ph.D., R.N.Senior Associate Dean for Research, School of Nursing

Richard Caprioli, Ph.D.Biochemistry, Chemistry, PharmacologyDirector, Mass Spectrometry Research Center

Ellen Wright Clayton, M.D., J.D.Pediatrics, LawDirector, Center for Genetics and Health Policy

Ray N. DuBois Jr., M.D., Ph.D. Medicine, Cell & Developmental Biology,Cancer BiologyDirector, Digestive Disease Research Center

John H. Exton, M.D., Ph.D.Molecular Physiology and Biophysics,PharmacologyHoward Hughes Medical Institute investigator

Steven G. Gabbe, M.D.Obstetrics and GynecologyDean, School of Medicine

William N. Hance, B.A., J.D.Director, Office of News and Public Affairs

George C. Hill, Ph.D.Medical Administration, Microbiology &ImmunologyAssociate Dean for Diversity

Michael C. Kessen, B.A.Director, Corporate & Foundation RelationsMedical Center Development

Joel G. Lee, B.A.Associate Vice Chancellor, Medical Center Communications

Lee E. Limbird, Ph.D.Pharmacology

Mark A. Magnuson, M.D.Molecular Physiology and BiophysicsAssistant Vice Chancellor for Research

Lawrence J. Marnett, Ph.D.Biochemistry, Cancer ResearchDirector, Vanderbilt Institute of ChemicalBiology

John A. Oates, M.D.Medicine, Pharmacology

Alastair J.J. Wood, M.B., Ch.B.Pharmacology, MedicineAssociate Dean for External Affairs

Vanderbilt connectionsI congratulate you on the recent issue

of Lens on viral infections (Spring 2004),which is as fine a publication as I haveseen from Vanderbilt in a long time. Ifound all the articles stimulating andinformative, but I was particularlyimpressed by your article on Dr. AnthonyFauci and his laudatory efforts to dealwith the ravages of HIV/AIDS.

Dr. Fauci paid tribute to Dr. SheldonWolff in several places in the article,including his statement that Dr. Wolfflaunched him on his career ...

It should be noted that Sheldon hasan important relationship with Vanderbilt.He took his M.D. at Vanderbilt in 1957and was later a medical intern and resi-dent in medicine at Vanderbilt UniversityHospital. As your article states, Dr. Wolffhad a distinguished medical career prior tohis untimely death in 1994, including hisbeing the director of the Laboratory of Clinical Investigation at the NationalInstitute of Allergy and InfectiousDiseases at NIH and finally the chief ofmedicine at Tufts University.

I am pleased to remember him as mydear friend and fellow house officer atVanderbilt.

BOYD L. BURRIS, M.D.

Clinical Professor of Psychiatry

George Washington University Medical Center

Georgetown University Medical Center

Resident in Psychiatry at Vanderbilt (1956-1959)

Eradicating polioI am very impressed with the publi-

cation received this month from mybeloved alma mater. However the articleon polio by Lisa DuBois (page 25, Spring2004 issue) leaves out the impact ofRotary International, whose members havegiven $600 million and much manpowerto eradicate polio from the Earth.

I am aware that many of my Vanderbiltclassmates are also Rotarians; many likeme are past presidents of their respectiveclubs, and are very proud to be part of theelimination process.

PAUL HUCHTON, M.D.

El Paso, Texas

Vanderbilt University School of Medicine,

Class of '58

We goofed!We misidentified the scientific illus-

trator whose colorful depictions of theinfluenza virus appeared on the cover andon page 23 of the last issue of Lens.

Proper credit should be given toRussell Kightley of Canberra, Australia(www.rkm.com.au).

We sincerely regret the error.

Letters may be mailed to:Bill SnyderVanderbilt University Medical CenterCCC-3312 Medical Center NorthNashville, TN 37232-2390Or e-mailed to: william.snyder@vanderbilt.edu

Lens Editorial Board

LensL E T T E R S T O T H E E D I T O R

T h r o u g h o u r

Lens Vanderbilt University Medical Center CCC-3312 Medical Center Nor thNashville, TN 37232

Targets for drug discovery: an antibody binding siteon the cell surface (top left), the COX-2 enzymeinside the cell (bottom left), and a heterotrimericG-protein in the cell membrane (bottom right). G-proteins are “molecular switches” that convertsignals used to communicate between cells into signals that act inside the cell.

Illustration by Dominic Doyle. Courtesy of LawrenceJ. Marnett, Ph.D., and the Vanderbilt Institute ofChemical Biology.

I N T H E N E X T I S S U E :Linking bench to bedsideUniversity scientists are increasingly collaborat-ing with their peers in industry to improve thesearch for new drugs.

Dimming the switch How basic research led to the development ofallosteric modulators and a redefinition of theterm “medicate.”

Completing the circleThe study of drugs on the market revealsinsights into previously unrecognized biology –and to new pharmaceuticals.

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