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

Summary 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 ⁷-PGA was most marked, followed by that of ¹²-PGJ₂, PGJ₂ and PGD₂. When antineoplastic prostaglandins were administered to nude mice bearing HR cells, tumor growth in groups treated with PGJ₂ and 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 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 ⁷-PGJ₁, compared to the results in groups treated with PGD₂ alone, ⁷-PGJ₁ alone or cisplatin alone. Combination of PGJ₂ or 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 ⁷-PGJ₁ with cisplatin may be of clinical use for ovarian cancer resistant to cisplatin.Abbreviation Cisplatin cis-diamminedichloro-platinum(II)This work was supported in part by a grant-in-aid for comprehensive ten year strategy for cancer control from the Ministry of Health and Welfare of Japan (Y.K. and M.F.)