Response of human chorionic gonadotrophin to luteinizing hormone-releasing hormone stimulation in the culture media of normal human placenta, choriocarcinoma cell lines, and in the serum of patients with gestational trophoblastic disease.

In vitro and in vivo responses to luteinizing hormone-releasing hormone (LHRH) stimulation of human chorionic gonadotrophin (hCG) production were evaluated. We cultured placental tissues of ten weeks and term pregnancy, choriocarcinoma tissues, and monolayers of the BeWo cell line, and added serial dilutions of LHRH (1, 5 and 10 micrograms) to the media for five to seven days. In in vivo experiments, 100 micrograms LHRH was intravenously administered to 20 normally cycling women (control group), 27 women who were 'possible remission', and 21 women with 'minimal resistance' to gestational trophoblastic disease. After injection of LHRH, blood samples were collected at 0, 30, 60, 90 and 120 minutes. The concentrations of immunoreactive beta-hCG in in vitro culture media, and in sera from patients, were measured before and after LHRH stimulation by double-antibody radioimmunoassay. These in vitro and in vivo experiments revealed that normal and malignant trophoblastic cells responded to the LHRH stimulation by producing immunoreactive beta-hCG. Therefore, LHRH stimulation may be useful in detecting residual choriocarcinoma cells in gestational trophoblastic disease patients during their periremission periods.