Adenovirus mediated angiostatin gene therapy for ovarian cancer: experiment with nude mice

Abstract

To built an expression vector of angiostatin (AG) gene with recombinated replication defective adenovirus and investigate the therapeutic effect of human AG gene on ovarian cancer. (1) Human AG K (1 - 3) cDNA was inserted into the vector pShuttle to build the recombinant plasmid pShttle-AG (K1-3). pAdeno-X-AG (K1-3) was built by double-cut and recombinated pShttle-AG (K1-3) to vector pAdeno-X, and then recombinant adenovirus was finally prepared by transfection of pAdeno-X-AG (K1-3) into to the human embryo kidney cells of the line 293. (2) Human ovarian cancer cells of the line SKOV3 were inoculated subcutaneously into nude mice of the line BALB/c nu/nu to establish model of human ovarian cancer. Then the mice were randomly divided into 3 groups to be injected with Ad = AG (K1-3), Ad-LacZ, or phosphate buffered saline (PBS) around the cancer every 5 days. The tumor size was measured every 5 days to calculate the tumor volume and tumor inhibition rate. Three days after the last injection the mice were killed. The tumor tissues, livers, and kidneys of the mice underwent immunohistochemistry to calculate the microvessel density (MVD) and expression of vessel endothelial growth factor (VEGF) and AG. The tumor volume and weight of the Ad-AG (K1-3) group were significantly less than those of the PBS and Ad-LacZ groups (all P < 0.01), however, there were not significant difference between the latter two groups (both P > 0.05). The expression levels of CD34 and VEGF of the Ad-AG (K1-3) group were both significantly lower than those of the PBS and Ad-LacZ groups (all P < 0.01), however (both P > 0.05). Human angiostatin mediated by adenovirus suppresses the angiogenesis and the growth of human ovarian cancer in the nude mice model, which suggests that it is promising in clinical application.