Oncolytic Effect of a Recombinant Vesicular Stomatitis Virus Encoding a Tumor-suppressor MicroRNA in an Osteosarcoma Mouse Model

Abstract

Background/Aim: Attempts have been made to enhance treatment with vesicular stomatitis virus (VSV) for osteosarcoma. We have previously shown that VSV incorporated with miRNA143 enhanced the antitumor effect at some doses; however, the range of the doses was narrow. This has not been evaluated in vivo, and the synergistic effect of this antitumor effect in animals is unknown. The purpose of the study was to evaluate the oncolytic effect of VSV-miRNA on osteosarcoma cells in vivo. Materials and Methods: A novel oncolytic VSV was developed by incorporating the tumor-suppressor microRNA143 (rVSV-miR143). In order to compare the antitumor effects of administration methods (intravenous and intratumoral administration) of rVSV-miR143 with those of VSV, a comparative analysis of primary tumor volume, metastatic lesions and survival rate was performed in mouse models of osteosarcoma. Results: Following intratumoral injection, rVSV-miR143 showed a significant reduction in primary tumor volume, but no significant difference was observed in metastatic lesions and survival rate compared to VSV. Following intravenous injection, rVSV-miR143 revealed no significant difference in primary tumor volume, metastatic lesion and survival rate compared to VSV. Conclusion: VSV incorporating tumor-suppressor miRNA143 demonstrated a slightly synergistic antitumor effect on osteosarcoma in vivo.