In-Vitro Inhibition of Human Melanoma (BLM) Cell Growth by Progesterone Receptor Antagonist RU-486 (Mifepristone)

摘要

RU-486 is an abortifacient which is used to terminate early pregnancy. It acts by blocking progesterone receptor. In our earlier study with progesterone, RU-486 was used as a progesterone receptor antagonist to find out the mechanism of progesterone action on melanoma cells. Results indicated that the effect of progesterone was not mediated through progesterone receptor. In the course of experiments, it was observed that RU-486 by itself inhibited mouse melanoma cell growth. Further research work with RU-486 showed a dose dependent inhibition of human melanoma cell growth. The mechanism of inhibition of cell growth was due to apoptosis and this effect of RU-486 was neither mediated through progesterone receptor nor glucocorticoid receptor. This in-vitro study suggested that melanoma also could be a target for RU-486 action, apart from breast, ovary and prostate cancers.