In vitro chemosensitivity of paclitaxel and other chemotherapeutic agents in malignant gestational trophoblastic neoplasms.

This is the first report on the ATP cell viability assay as a chemosensitivity test system for gestational trophoblastic neoplasms (GTN). We obtained chemosensitivity profiles in two established trophoblastic cell lines and four fresh tumors. Ten drugs were tested in vitro in the two cell lines JAR and JEG-3. The IC50 values of the 10 chemotherapeutic agents tested were very similar for both cell lines. The three most active drugs in these cell lines were VP-16, paclitaxel and vincristine. This is the first report on the activity of paclitaxel in trophoblastic cell lines. We furthermore evaluated this assay for chemosensitivity testing in four fresh malignant GTN tumors: one placental site trophoblastic tumor, one chorocarcinoma and two invasive moles. The placental site trophoblastic tumor specimen revealed to be rather chemoresistant in vitro whereas the other three tumors were chemosensitive. From our cell line data we conclude that the ATP cell viability assay is a practicable assay for chemosensitivity testing of GTN cell lines and gives repeatable results. However, the value of this assay for fresh GTN chemosensitivity testing needs to be defined.