Combination of Bevacizumab and Acyclic Retinoid Inhibits the Growth of Hepatocellular Carcinoma Xenografts

The prognosis of patients with hepatocellular carcinoma (HCC) is poor and the development of effective treatments for this malignancy, including combination chemotherapy, is required. This study examined the possible combined inhibitory effects of bevacizumab, an anti-vascular endothelial growth factor monoclonal antibody, and acyclic retinoid (ACR), which can prevent the development of HCC, on the growth of Huh7 human HCC cells. Xenograft tumors were produced by subcutaneously injecting Huh7 cells into nude mice. Starting 1 wk after the tumor cell injection, the mice were treated with bevacizumab alone (5 mg/kg body weight, subcutaneous injection, twice a week), ACR alone (given in a diet containing 0.03%), or their combination for 6 wk, and the effects of these regimens on xenograft growth were examined. Combined treatment with bevacizumab plus ACR significantly suppressed the growth of Huh7 xenografts. The combination of these agents significantly inhibited the phosphorylation of the Akt protein in tumor tissues. With combination therapy, the population of Ki-67-positive cells in xenografts decreased, while that of TUNEL-positive cells increased. The combination of bevacizumab and ACR exerts growth-suppressing effects on HCC cells by inhibiting cell proliferation and inducing apoptosis. This combination might be an effective regimen for the treatment of HCC.