LI Baoª²Jin1,2, ZHANG Chao1, ZHOU Yuª²Mei3, HAO Ying1, LIU Xiaoª²Ping1, OU Qingª²Jia2

    1Department of Hepatobiliary and Laparoscopic Surgery, Shenzhen Hospital, Peking University, PKUª²HKUST Medical Center, Shenª²zhen 518036, China, 2Department of Hepatobiliary Surgery, Second Affiliated Hospital, Sun Yatª²Sen University, Guangzhou 510120, China, 3Department of Nursing, Affiliated Hospital, Jinggangshan university, Ji¬ðan 343000£¬China

    ¡¾Abstract¡¿ AIM: To explore the therapeutic efficacy and mechanism of HSVª²tk for targeting angiogenesis against hepatocellular carcinoma. METHODS: By using pAdeasy system, recombinant adenovirus containing kinase domain receptor (KDR) or cytoª²megalovirus (CMV) promoterª²controlled HSVª²tk gene (AdKDRª²tk and AdCMVª²tk) was constructed. The virus was used to infect KDRª²expressed human umbilical venous endothelial cells (HUVEC) and KDRª²unexpressed HepG2. Following administration of ganciclovir (GCV), the survival rate of geneª²transfected HUVEC and HepG2 was evaluated by using MTT method. Hepatocarciª²nomas were transplanted in 32 Balb/c mice with HepG2 cells, which were subsequently divided into 4 groups: GCV group (¢ñ), Ad group (II), AdCMVª²tk group (III) and AdKDRª²tk group (IV). Then selective administration of recombinant adenovirus or Ad intratumorally was performed in all rats. GCV was given at a dose of 100 mg/(kg¡¤d) ip in the following days and for 10 d. Microvessel density (MVD) of tumor in all the treated animals was checked with the immunohistochemical methods and tumor burden was assessed 10 d before and after the last GCV administration. RESULTS: The pAdeasy system produced a high titer of the recombinant adenovirus [(1¡Á1013) pfu/L]. When the multiplicity of infection (MOI) was 100, with increasing GCV concentration from 0 up to 50 mg/L, the survival rate of AdKDRª²tkª²transfected HUVEC and HepG2 decreased from (90.7¡À4.5)% and (91.8¡À4.3)% to (28.9¡À5.7)% and (75.4¡À2.9)%, respectively (P<0.01), while the survival rate of AdCMVª²tkª²transfected HUVEC and HepG2 declined from 100% to (17.6¡À2.5)% and (23.2¡À5.7)%, respectively (P>0.05). Compared with group¢ñ,there was a decrease of tumor weight by (14.7¡À3.2)% in group III and (23.6¡À5.6)% in group IV, respectively; and there was a distinct difference between group III and IV (P<0.05). The median MVD was 37.4¡À8.6 ......