BACKGROUNDThalidomide is reviving for its antiangiogenic effect on corneal neovascularization models. Recently, it has been employed in tumor research in several types of solid carcinomas. However, its effect on hepatocellular carcinoma (HCC) has not yet been clarified.

METHODSA total of 48 nude mice bearing human HCC with a high metastatic potential were randomly divided into 4 groups. Thalidomide (200 mg/kg), paclitaxel (13 mg/kg), or their combination, which was dissolved in 0.5% sodium carboxyl methyl cellulose (CMC) suspension, was intraperitoneally injected in each group since the second day of the establishment of animal model. The group simply administered with 0.5% CMC was set as placebo-control. The mice were sacrificed on the 30th day, for the measurement of tumor size, weight and metastasis in the lungs. The levels of CD34 and endothelial growth factor (VEGF) mRNA in tumor tissues were detected by immunohistochemistry and semiquantitative RT-PCR, respectively, and microvessel density (MVD) was evaluated.

RESULTSNo statistical difference was found in tumor weight and volume between the thalidomide group and control (P>0.05). Paclitaxel showed a growth-inhibiting effect on tumors (P<0.05). The value of MVD and VEGF mRNA and metastases to the lungs in each group were lower than those in the placebo-control group (P<0.05); such difference in the combination group was statistically significant (P<0.05).

CONCLUSIONSPaclitaxel, but not thalidomide, has significant growth inhibitory effect on tumors, but both significantly inhibit angiogenesis and metastasis of human HCC in nude mice, such effects of paclitaxel can be amplified by thalidomide.