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094

DETECTION BY IN SITU HYBRIDIZATION OF A LOW EXPRESSION OF NUCLEAR RETINOIC ACID RECEPTOR BETA (RAR-8) BUT NOT RAR-a AND RAR-y IN HUMAN LUNG CANCER SPECIMENS. X-C. Xu,’ G. Sozzi,* J. Ro,t J.S. Lee.1 U. Pastorino.2 S. Pilotti,* J. Kurie.1 W.K. Hong,’ and R. Lbtan.’ ‘University of Texas, M. D. Anderson Cancer Center, Houston, Texas, USA and *Istituto Nazionale Tumori, Milano, Italy.

Vitamin A and some of its analogs (retinoids) have been shown to suppress lung carcinogenesis in experimental animal models, to reverse premalignant oral lesions, and prevent the development of second primary tumors in the aerodigestive tract in patients with cancer of the head and neck or lung. It is thought that these effects result from the ability of retinoids to restore normal cell growth and differentiation. Nuclear retinoic acid receptors (RARs), which am retinoid-activated transcription factors, are considered to be the ultimate mediators of retinoid actions. Therefore, alterations in their expression could lead to cancer development. In this regard it is of interest that several studies have shown-by Northern blo&ng that many lung cancer cell lines fail to express RAR-8. To determine whether the expression of RARs’ mRNAs in lung cancer is also abnormal in vivo, we used digoxigenin-labeled antisense riboprobes of three RARs @AR-a, RAR-8, and RAR-y) for in situ hybridization to histological sections of formalin-fixed, paraffin- embedded specimens from normal lung, bronchial metaplasia, lung tissue from resection margin, dysplastic tissue, and lung cancer. The results demonstrate that 50% of dysplastic tissues, and >50% of lung adenocarcinoma and squamous cell carcinomas do not express RAR-b, whereas the expression of the other receptors was not altered. The decrease in RAR-8 expression was observed in histologically normal bronchial epithelium at the resection margin. These results support the hypothesis that altered expression of retinoid receptors plays a role in lung carcinogenesis and indicate that the decreased expression of RAR-8 is an early event in the development of some lung cancers. Supported in part by USPHS grant POlCA52051 from the NCI.

095

PROGNOSTIC SIGNIFICANCE OF THE SERUM PROTEIN CONTENT IN LUNG CANCER (LC). Gianhnw Lhxheri, Lkmmiw Ferrigno The A. Carle Hospiatel of Chest Diseases, Cuneo, Italy.

Several factors are known as important determinants of the prognosis of lung cancer. Multivarlate equations, contahting multiple influential facmrs, are strot@y predictive of the outcome, and yet they can only predict a scarce 50% of the natural varlabillty. It follows that a myriad of other less important factors remain unknown, even if they could help substantially to explain why that given patient has a survival of that particular duration. la this study we aimed to assess the potential progmytlc si8nificance of the serum protein content. We stodll 454 consecutive patients, seen for a new lung cancer during the last S years, by obtaining their serum concentration of total proteins (TP), albumin (A), hnnnmoglobulii (IgG,lgA,lgM), trsnsferrin (T), haptodobin (HP), alphal -8lycoprotein acid (GA), and alpha1 -antltrypsin (AT). In 364 of them all pmtein msasunstnents, in eddltlln to values of other 36 variables of various type (antbropotnetric, clinical, radiological, hItoparbologicsl, and laboratory data), were available. Univarlate analyses showed that patients with transferrin above 218 mg/dl had a me&n survival of 9 months (95% confidence interval, C.1.:7-10). as compared to the 7 months of the remaining subjects (C.l.:5-7, pcO.01). Patients with AT above 281 mg/dl survived significantly less than patients with low AT (I 1 months, C.I.:9-13, vs 6 months, C.I.:4-6, pcO.01). Hi8h HP and GA were also significantly associated with a poor prognosis (p<O.Ol and 0.05, respectively). A multivariate analysis of survival (the Cox’s re8ression model), including 364 cases and 41 variables selected as significant: 1. stage of disease; 2. ECGG pertbrmance status; 3. sex; 4. alpha1 -glycoprotein acid; 5. weight loss; 6. histology.

GANGLIOSIDES AS ANTIGENIC TARGETS FOR ACTIVE AND PASSIVE IMMUNIZATION OF PATIENTS WITH SMALL CELL LUNG CANCER (SCLC). S.C. Grant, M.G. Kris, P.B. Chapman, C. Cordon-Cardo, L. Kostakoglu, H.F.Oettgen, N.K.V. Cheung. Memorial Sloan-Kettering Cancer Center, New York, NY, U.S.A.

Most patients with SCLC die of their disease, despite high response rates to chemotherapy. Presumably, microscopic tumor can remain despite complete responses and it is not eliminated by additional chemotherapy. SCLC tumor specimens and cell-lines were analysed by immunohistochemistry and/or by immune-thin layer chromatography for expression of gangliosides G,, and GD3. The majority were positive for either or both gangliosides, which are expressed on few normal tissues and are potential antiaenic tarnets for immune therapy.

Passive Immunira~ion: A mouse SCLC xenograft model was used to evaluate targeting of GD2 +ive human SCLC xenografls by an ‘251-labelled anti-G,, mAb Targeting to GD2 +ive tumors was demonstratedby radionuclide scans. Tumor:blood ratios of up 4O:l were seen at autopsy.

In a pilot trial 10 patients with SCLC received 5OOpg “‘I-labeled 3F8, an anti-G,, monoclonal antibody (mAb). Radionuclide imaging demonstrated localization to all known sites of disease in all 10 patients. Tissue was available in one patient in whom radio-localization to tumor sites was confirmed pathologically.

Active Immunization: Patients with SCLC who achieved a major response to initial therapy were immunized with the anti-idiotype mAb BEC2 plus BCG as adjuvant. BEC2 mimics the ganglioside G,, and has been shown to induce anti-G,, antibodies in patients with melanoma who have not received chemotherapy. To date 6 patients have received BEC2 2.5 mg + BCG on weeks 0,2,4,6, & 10. Serial blood samples are being assayed for anti-BEC2 and anti-Gn, antibodies.

The results of our trials to date indicate that GD2 and G,, are appropriate immunologic targets in patients with SCLC. Further studies are ongoing. Supported in part by ImClone Systems Incorporated.

096

NCAM (NEURAL CELL ADHESION MOLECULE) (CD56) EXPRESSION BY SMALL CELL CARCINOMAS (SCC) DIFFERS FROM EXPRESSION SHOWN BY NEUROBLASTOMA CELL LINES AS DETECTED BY UNIQUE MONOCLONAL ANTIBODIES KDll AND MGS. A.M.C. Koros and R. Gerardy-Schahn. Univ. of Pittsburgh, GSPH, Pgh, PA 15261 and Inst. for Med. Mikrobiologie, Hannover, Germany 30623.

NCAM (CD56) expression has been described on small cell carcinomas (SCC) of lung and other organs as well as a small percentage of non-small cell carcinomas (NSCC) [Koros et al. Lung Cancer 4, 52 (1988), Carbone er al. Cancer Res.51, 6142 (1991)]. Identification of NCAM has been primarily by indirect immunofluorcscencc and flow cytometry using MOAB NKHl (N901) (CD56) (Cou1tc.r Immunology). Two new, unique MOABS, KDll and MG5 (Gerardy-Schahn) have been reported recently to identify an intmcytoplssmic epitopc on neuroblastoma cell lines and human brain (Gerardy-Schahn and Eckardt, Znr. d Carter in press). The current report describes surface expression of NCAM detected by indirect immunofluorescence and flow cytometry using KDI 1 and MG5. SCC lines SHP-77 (E. Fisher and J. Paulson), NCI-H69, NCI-H146, and NCI-HSlO (A.F. Gazdar), were analyzed using a single argon laser (Profile II). All SCC lines were positive. MOLT4 (T lymphoblastoid), MCF7, CAMAl, and BT483 (breast carcinomas) were also positive. Other breast lines BT20, SKBR-3 and Simmons Cancer Center lines-70 and -202 (Gazdar) were negative for both MOABS as were prostate lines PC3 and DU145. One Simmons Cancer Center breast line - 38 was positive for KDl 1 but negative for MG5. The heterogeneity of expression of the epitopes detected by KDl 1 and MG5 may reflect patient tumor heterogeneity and may have relevance for future MOAB - targeted therapy.