Adjuvant effects of antineoplastic prostaglandins to cisplatin in nude mice bearing human ovarian cancer cells.

Effects of antineoplastic prostaglandins (PG) on human ovarian cancer cell growth were examined by using HR cells derived from ascites of a patient with serous cystadenocarcinoma of the ovary. With regard to inhibition of cancer cell proliferation in vitro, the effects of delta 7-PGA1 was most marked, followed by that of delta 12-PGJ2, PGJ2 and PGD2. When antineoplastic prostaglandins were administered to nude mice bearing HR cells, tumor growth in groups treated with PGJ2 and delta 12-PGJ2 alone was significantly inhibited 63 days after tumor inoculation, compared to that in an untreated group. Consequently, a significant prolongation of median survival was obtained with delta 12-PGJ2, compared to that in untreated groups and in groups with cisplatin alone. In addition, when prostaglandins were administered together with cisplatin, adjuvant inhibitory effects on the tumor growth were obtained 35, 56 and 63 days after tumor inoculation. Subsequently a significant prolongation of median survival was observed when cisplatin was combined with PGD2 or delta 7-PGA1, compared to the results in groups treated with PGD2 alone, delta 7-PGA1 alone or cisplatin alone. Combination of PGJ2 or delta 12-PGJ2 and cisplatin resulted in a significant decrease of hematocrit and body weight 63 days after tumor inoculation, suggesting a deterioration of the median survival. These results suggest that combination of PGD2 or delta 7-PGA1 with cisplatin may be of clinical use for ovarian cancer resistant to cisplatin.