Leptin regulates the proliferation and apoptosis of human endometrial epithelial cells

The biological functions of leptin in the human endometrial epithelium were investigated using the human endometrial epithelial cell line, HHUA. Specifically, the effects of leptin on the proliferation and apoptosis of HHUA cells induced by treatment with anti-Fas IgM or anticancer drugs were examined. RT-PCR detected the expression of four leptin receptor isoform mRNAs in the cells and flow cytometric analysis revealed cell surface expression of the leptin receptor molecules. Leptin stimulated HHUA cell proliferation in a dose-dependent manner at concentrations below the normal serum leptin level. Leptin enhanced anti-Fas IgM-mediated growth inhibition and DNA fragmentation, but did not enhance the expression of either Fas antigen or Fas ligand. Moreover, leptin had no effect on anticancer drug-induced apoptosis. Based on these results, leptin at a physiological serum concentration, may regulate the remodeling of the human endometrial epithelium by stimulating cell proliferation and enhancing the Fas-specific intracellular apoptotic signaling pathway.