Construction of cancer-specific replication-competent adenovirus vector expressing IL-18 gene and its cytotoxic effect on hepatocellular carcinoma cells in vitro / 肿瘤

ABSTRACT

Objective: To construct conditional replication adenovirus vector CNHK600-IL-18, in which the IL-18 expression was driven by hypoxia promoter and adenovirus replication was regulated by human telomerase reverse transcriptase (hTERT) promoter. Specific replication ability and the killing effect of CNHK600-IL-18 on hepatocellular carcinoma (HCC) cells were investigated. Methods: Viral replication experiments (TCID50 method) were performed to evaluate the selective replication ability of pSG600 and CNHK600-IL-18 during 96 h in three different hepatocellular carcinoma cell lines. MTT assay was applied to evaluate the killing efficacy of pSG600 and CNHK600-IL-18 on the three HCC cell lines at different MOI. BJ cells were infected with CNHK600-IL-18. The supernatant was collected and the level of IFN-γ secreted by T cells was measured. Results: Western blot showed that IL-18 was detected in SMMC-7721 cells after CNHK600-IL-18 infection. The supernatant of CNHK600-IL-18 -infected BJ cells induced T cells to secret IFN-γ. CNHK600-IL-18 replications in HCC cell lines BEL-7404 and SMMC-7721 were 31 658 and 125 396 after 96-h incubation, respectively, which were 400 and 1587 folds as much as in BJ cell line. Conclusion: CNHK600-IL-18 selectively replicates in HCC cells and generated bioactive IL-18 with high efficacy. CNHK600-IL-18 has an obvious tumor-killing effect against HCC.