MAPK3 and hepatocellular carcinoma: The effects of cyclosporine A on cell proliferation and the cell cycle have been previously studied in various human cell types, yielding the following findings: Cyclosporine A activates the extracellular signal-regulated kinase (ERK1/2) signaling pathway and enhances the proliferation of HepG2 (human hepatocellular carcinoma-derived cell line) proliferation [26].