Protein Kinase C-Dependent and -Independent Pathways Mediate Epidermal Growth Factor (EGF) Effects in Human Endometrial Adenocarcinoma Cell Line KLE

Abstract The role of EGF in the proliferation of the poorly differentiated endometrial adenocarcinoma cell line (KLE) was examined. EGF (10 ng/ml) and the tumor promoter, protein kinase C agonist, phorbol 12-myristate 13-acetate (PMA) were potent stimulators ( P 3 H]thymidine incorporation into DNA. Staurosporine, a protein kinase C inhibitor, partially blocked the EGF effects on [ 3 H]thymidine incorporation. Similarly, downregulation of protein kinase C also failed to completely abolish EGF effect on DNA synthesis and cell division. These results suggest that in the KLE cell line EGF stimulation of cell growth is exerted through both protein kinase C-dependent and -independent pathways.