Cell Cycle Arrest in Endometrial Carcinoma Cells Exposed to Gonadotropin-Releasing Hormone Analog

Abstract Gonadotropin-releasing hormone (GnRH) has been shown to have an inhibitory effect on the growth of several hormone-dependent human tumors. We have treated a human endometrial cancer cell line which expresses GnRH receptor with GnRH analog, D-Trp 6 -LHRH, in order to study whether there are differences in cell cycle kinetic response. Flow cytometric analysis revealed that cultured carcinoma cells showed a cell cycle arrest at the G 1 –S transition after treatment with 10 μM D-Trp 6 -LHRH for 36 h. Western blot analysis showed that the level of p16 protein was obvious following 24 h of D-Trp 6 -LHRH treatment. These results suggest that the mechanism by which GnRH inhibits the growth of endometrial carcinoma cells may include effects on cell cycle arrest.