Antitumor activity of 13,14-dihydro-15-deoxy-Delta(7)-prostaglandin-A(1)-methyl ester integrated into lipid microspheres against human ovarian carcinoma cells resistant to cisplatin in vivo

One of the Delta(7)-prostaglandin A(1) derivatives with unique antitumor ac tivities, 13,14-dihydro-15-deoxy-Delta(7)-prostaglandin-A(1)-methyl ester, was integrated into lipid microspheres (Lipo-TEI9826) and examined for its antitumor effect in vitro and in vivo. The in vitro relative resistance of human ovarian cancer, A2780(CP), to cisplatin (CDDP) and Lipo-TEI9826 was 2 7.3 and 2.0, respectively, compared with A2780, the parent cell line of A27 80(CP). In in vivo experiments, when A2780(CP) and the parent cell line A27 80 were inoculated into nude mice, A2780(CP) grew two times more rapidly th an did A2780, The growth of A2780(CP) tumor was not suppressed by CDDP, whe reas that of the A2780 tumor was significantly suppressed. Nevertheless, th e growth of both the A2780 and the A2780(CP) inoculated tumors was signific antly inhibited by treatment with Lipo-TEI9826 at any time after the initia l treatment, compared with the lipid microspheres only. These results show that Lipo-TEI9826 may be an effective antitumor agent and capable of overco ming CDDP resistance.