Antitumor activity of 13,14-dihydro-15-deoxy-delta7-prostaglandin-A1-methyl ester integrated into lipid microspheres against human ovarian carcinoma cells resistant to cisplatin in vivo.

One of the delta7-prostaglandin A1 derivatives with unique antitumor activities, 13,14-dihydro-15-deoxy-delta7-prostaglandin-A1-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, A2780CP, to cisplatin (CDDP) and Lipo-TEI9826 was 27.3 and 2.0, respectively, compared with A2780, the parent cell line of A2780CP. In in vivo experiments, when A2780CP and the parent cell line A2780 were inoculated into nude mice, A2780CP grew two times more rapidly than did A2780. The growth of A2780CP tumor was not suppressed by CDDP, whereas that of the A2780 tumor was significantly suppressed. Nevertheless, the growth of both the A2780 and the A2780CP inoculated tumors was significantly inhibited by treatment with Lipo-TEI9826 at any time after the initial treatment, compared with the lipid microspheres only. These results show that Lipo-TEI9826 may be an effective antitumor agent and capable of overcoming CDDP resistance.