Adenovirus-mediated herpes simplex virus thymidine kinase gene transfer driver by KDR promoter in treatment of experimental human hepatocelLular carcinoma in nude mice

Abstract

To investigate the therapeutic efficacy of adenovirus-mediated herpes simplex virus thymidine kinase (HSV-tk) gene transfer under the driving of KDR promoter (AdKDR-tk) in combination of ganciclovir (GCV) against human hepatocellular carcinoma in nude mice. HepG2 cell line was implanted subcutaneously into 32 nude mice, which were subsequently divided into 4 groups (n=8 each group): Ganciclovir group (I), Ad group (II), AdCMV-tk/GCV group (under the driving of CMV promoter) (III) and AdKDR-tk/GCV group (IV). Then intratumoral injection of recombinant adenovirus or Ad was performed in all nude mice, and repeated 24 h later. For the following 10 d GCV was given at a dose of 100 mg/(kg·d), ip. All the treated animals were killed to evaluate the tumor weight and the histopathological changes and the microvessel density of tumors after the treatment was determined. Compared with group I, the tumor inhibitory rate was 12.3% in group III and 24.5% in group IV; the inhibition rates were significantly different between group III and IV (P<0.05). The mean MVDs in group I, II, III and IV were 37.4±8.6, 30.6±7.8, 27.6±7.1, and 10.7±4.1 (microvessels/mm2), respectively. Significant differences were found between group III and II (P<0.05), IV and II (P<0.01), and IV and III (P<0.01). Intratumoral injection of AdKDR-tk results in marked inhibition of HCC growth through inhibition angiogenesis in nude mice. It may be a new treatment approach for human HCC.