COMBINATION EFFECT OF ANTI-FAS ANTIBODY AND CHEMOTHERAPEUTIC DRUGS INOVARIAN-CANCER CELLS IN-VITRO

To clarify the significance of the Fas antigen (Ag) in gynecologic tum ors, its expression in gynecologic cancer cell lines was examined. The Fas Ag was expressed in 6 of 15 cell lines. Five of 8 ovarian cancer cell lines but none of 4 choriocarcinoma cell lines expressed the Fas Ag. In drug-resistant cell lines derived from one of the Fas-positive cells, its expression was not lost after development of resistance to cisplatin, SN-38 or etoposide, but its expression was absent in the ce ll line resistant to Adriamycin. The effect of the anti-Fas antibody ( Ab) was then studied. Apoptosis was induced in 7 of 9 Fas-positive cel l lines, whereas the remaining two cell lines were unaffected. Further more, the combination effect of the anti-Fas Ab and drugs was examined in an ovarian cancer cell line and its drug-resistant variants, and a synergistic effect was observed. These results suggest important role s of the Fas Ag in ovarian cancer and the potential for overcoming dru g resistance by a combination of the anti-Fas Ab and various drugs.