Effects of Taxol on choriocarcinoma cells

Taxol (Bristol-Myers Squibb) (paclitaxel) has been shown to be a potent inhibitor of cell growth for a variety of tumors. We were interested in the antiproliferative efficacy and biologic properties of this novel antineoplastic agent in choriocarcinoma cells.

Human choriocarcinoma cell lines JAR and BeWo were cultured as monolayers and treated with Taxol.

Proliferation of JAR and BeWo cells was inhibited by Taxol in a dose-related manner and 1 to 3 nmol/L was sufficient to achieve 50% growth reduction. This effect was accompanied by a marked induction of human chorionic gonadotropin secretion. The effect on human chorionic gonadotropin secretion was dependent on intact protein biosynthesis but not mediated by augmented messenger ribonucleic acid expression. In these choriocarcinoma cells Taxol promoted differentiation as shown by an increase in syncytiotrophoblastic-like cells. Combination of Taxol with either etoposide or methotrexate resulted in antagonistic growth inhibition.

Taxol is a highly effective antineoplastic agent in choriocarcinoma cells, and clinical trials in refractory disease would therefore be warranted. However, substances other than etoposide or methotrexate should be evaluated for combined treatment. In addition to growth inhibition, differentiation is also induced by Taxol, as shown by increased human chorionic gonadotropin secretion and changed morphologic features.