Modulation of secretion of human chorionic gonadotropin by biologic response modifiers on term placenta and choriocarcinoma cells.

The effects of biologic response modifiers such as interferon-gamma, tumor necrosis factor alpha (TNF), and retinoic acid on the human chorionic gonadotropin (hCG) secretion of cultured choriocarcinoma cells (JAR) and term placenta have been studied. Although the proliferation of JAR cells was not inhibited by these agents, retinoic acid and TNF markedly increased both the intracellular levels as well as the secreted amounts of hCG. In the case of the term placenta, only retinoic acid increased the hCG secretion into the culture medium, whereas interferon-gamma and TNF both markedly reduced secretion. The cytostatic agent etoposide (VP-16) was able to augment the hCG secretion on the choriocarcinoma cells but did not alter its production on term placenta. The The data presented indicate different mechanisms of regulation of hCG secretion in the normal and malignant trophoblast.