To study the effects of pegvisomant in HCC cells, we cultured HepG2, SNU-387, SNU-423, and SNU-475 cells in FBS free medium, then stimulated these cells with GH in the presence or absence of pegvisomant at a concentration of 6 or 18 μg/mL for 48 h. The gene discussed is GH1; the disease is hepatocellular carcinoma.