Efficacy of the Chinese traditional medicinal herb Celastrus orbiculatus Thunb on human hepatocellular carcinoma in an orthothopic fluorescent nude mouse model.

This study aimed to explore the inhibitory effect of Celastrus orbiculatus Thunb. (COT) on tumor growth, metastasis and antiogenesis of hepatocelluar carcinoma (HCC) in an orthotopic nude mouse model using fluorescence imaging technology. Human HCC Hep-G2 cells expressing red fluorescent protein (RFP) were orthotopically implanted onto the liver of nude mice. One group of mice was treated with ethyl acetate extract of COT p.o. at a dose of 20 mg/kg starting on day 3 post-tumor implantation (early treatment). All other mice were randomized into four groups from day 20 post-tumor implantation and received either no treatment, oxaliplatin (25 mg/kg), or low-dose (20 mg/kg) or high-dose (40 mg/kg) COT. Real-time whole-body fluorescence imaging was performed to measure tumor growth and monitor metastasis development during the study. Vascular endothelial growth factor(VEGF) expression in the tumors collected at autopsy was analyzed by immunohistochemical staining and reverse transcription-polymerase chain reaction(RT-PCR). High-dose treatments, early treatment with COT, demonstrated significant efficacy on controlling tumor volume and tumor weight in the human HCC Hep-G2 orthotopic tumor model. No significant differences were found for metastasis incidence among the different study groups. VEGF expression in the tumors was significantly reduced by oxaliplatin and COT treatment. This study demonstrates the inhibitory efficacy of COT on the growth of HCC tumor. VEGF inhibition may contribute in part to the inhibition of HCC tumor growth. The results of the present report suggest COT has potential to treat HCC.