EFFECT OF CIS-DIAMMINEDICHLOROPLATINUM(II) AND ADRIAMYCIN COMBINATIONON OVARIAN-CARCINOMA

By continuous exposure to either cis-diamminedichloroplatinum (II) (CD DP) or adramycin (ADM), NOS2 cells, derived from human serous cystaden ocarcinoma of the ovary, acquired 7 times resistance to CDDP and 24 ti mes stronger resistance to ADM, respectively. The ADM-resistant cells showed cross-resistance to more drugs than the CDDP-resistant cells. W e examined the usefulness of combination therapy with CDDP and ADM in eight cell lines derived from human ovarian carcinomas and CDDP - as w ell as ADM - resistant cell lines using either isobologram or combinat ion index (CI); both examinations revealed additive effects in seven o f the eight cell lines and antagonistic effects in one cell line. Furt hermore, we studied effects of CDDP combined with 5-fluorouracil (5-FU ), etoposide (VP16) or camptothecin (CPT11) by CI method, which had a lower value in the regimen combined with 5-FU than that with ADM, repr esenting a favorable effect. VP16 and CPT11 had almost the same CI val ue as thatn of ADM. There is no evidence that the combination of ADM a nd CDDP is more useful than that of any other anticancer drug and CDDP in vitro.