SC430 Molecular Cell Biology

• Welcome to Our Last Seminar - Unit 9• Tonight we will discuss

– Cancer, cancer treatment and prevention– I will be available at AIM:KaplanHallPogar

before and throughout the seminar if you have any questions or issues.

• We will begin promptly at 8:00pmET

2

Unit Review

• Final Project Due– Remember it is not a term paper on an

infectious disease

• Review gradebook and submit any late work

• Unit 10 Final Exam

3

Cancer Tonight

• Cancer and the effects on the immune system

• How do these topics play a role

– Metastasis

– Immunotherapy

– Chemotherapy

– Radiation

4

What Is Cancer?

5

What Causes Cancer?Some viruses or bacteria

HeredityDiet

Hormones

RadiationSome chemicals

6

Heredity? Behaviors? Other Factors?

100

50

50

Stomach Cancer(Number of new cases

per 100,000 people)

U.S.Japan Japanese familiesin U.S.

100

70

7

0

Colon Cancer(Number of new cases

per 100,000 people)

U.S.Japan Japanese familiesin U.S.

7

Population-Based Studies

CANADA:Leukemia

Regions of Highest Incidence

BRAZIL:Cervicalcancer

U.S.:Coloncancer

AUSTRALIA:Skincancer

CHINA:Livercancer

U.K.:Lungcancer

JAPAN:Stomachcancer

8

• Cell division is the process through which a cell copies itself

• Cancer begins when the a cell divides although it should not

• Unregulated cell division leads to a tumor, a mass of cells with no apparent function in the body

9

Different Kinds of Cancer

Lung

Breast (women)

Colon

BladderProstate (men)

Some common sarcomas:Fat

Bone

Muscle

Lymphomas:Lymph nodes

Leukemias:Bloodstream

Some common carcinomas:

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• Benign tumors do not affect surrounding structures

• Malignant tumors invade surrounding structures and are cancerous

• Malignant tumors can break away and start new cancers elsewhere through the process of metastasis

11

Loss of Normal Growth Control

Cancer cell division

Fourth orlater mutation

Third mutation

Second mutation

First mutation

Uncontrolled growth

Cell Suicide or Apoptosis

Cell damage—no repair

Normal cell division

12

Malignant versus Benign Tumors

Malignant (cancer) cells invade neighboring tissues, enter blood vessels, and metastasize to different sites

Time

Benign (not cancer) tumor cells grow only locally and cannot spread by invasion or metastasis

13

Cancer Tends to Involve Multiple Mutations

Malignant cells invade neighboring tissues, enter blood vessels, and metastasize to different sites

More mutations, more genetic instability, metastatic disease

Proto-oncogenes mutate to oncogenes

Mutations inactivate DNA repair genes

Cells proliferate

Mutation inactivates suppressor gene

Benign tumor cells grow only locally and cannot spread by invasion or metastasis

Time

14

Earlier detection and treatment of cancer greatly increase the odds of survival.

Early Cancer May Not Have Any Symptoms

Therefore, knowing the warning signs of cancer is important to health

15

• Biopsy = the surgical removal of cells, tissue, or fluid for analysis

16

Biopsy

Patient’stissue sample

or blood sample

Genomic profile

Proteomic profile

Pathology

17

• Chemicals that kill dividing cells are injected into the bloodstream during chemotherapy

• High energy particles damage DNA in radiation therapy, so cells don’t divide

18

Biological therapy or Immunotherapy

• Biological therapies use the body's immune system– to fight cancer – to lessen the side effects that may be caused by some cancer

treatments

• Immune system may recognize the difference between healthy cells and cancer cells– Attack cancer cells just like bacteria or virus

• Antibodies, cytokines, and other immune system substances can be produced in the laboratory for use in cancer treatment

• More information at: http://www.cancer.gov/cancertopics/factsheet/Therapy/biological

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Biological therapies may be used to:

• Stop, control, or suppress processes that permit cancer growth.• Make cancer cells more recognizable and, therefore, more

susceptible to destruction by the immune system.• Boost the killing power of immune system cells• Block or reverse the process that changes a normal cell or a

precancerous cell into a cancerous cell.• Enhance the body's ability to repair or replace normal cells

damaged or destroyed by other forms of cancer treatment, such as chemotherapy or radiation.

• Prevent cancer cells from spreading to other parts of the body.

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Cancer Prevention

Cancer viruses or bacteria

Carcinogenic radiation

Carcinogenic chemicals