Anti-tumor Effect Of Oncolytic Vaccinia Virus Carrying SIKE Gene

Recently,the incidence and mortality of cancer have gradually increased,which threaten human being’s life and health.Conventional treatments of cancer include surgery,radiotherapy,and chemotherapy.Due to various factors,the efficacy of malignant tumor therapy is still unsatisfactory.Therefore,it is necessary to find more effective treatments.Targeted gene-virus therapy is a new direction of anti-tumor research based on its target specific selectivity,high expression efficiency,low cost and strong antitumor effects.IKKεand TBK1 are not only related to the occurrence,development,and malignant mofification of tumors,but also mediate the release of antiviral factors.SIKE is a physiological inhibitor gene of IKKεand TBK1.In this study,the advantages of exogenous gene SIKE and oncolytic vaccinia virus were integrated.In order to obtain the recombinant virus onco VV-SIKE,SIKE gene was inserted into the p CB plasmid and homologously recombined with wild vaccinia virus WR strain.Firstly,the MTT experiment showed that the recombinant virus onco VV-SIKE had stronger inhibitory effect compared with the control of onco VV,especially in liver cancer,breast cancer,and brain glioma.The recombinant virus had anti-tumor effect on hepatocellular carcinoma MHCC97-H cells and human glioma U87 cells,and is significantly stronger than the clinical virus onco VV-GMCSF,indicating that onco VV-SIKE had the clinical application prospect.The TCID₅₀experiment results showed that SIKE gene could significantly enhance the replication ability of the virus,and its replication is independent of the ERK signal pathway in liver cancer cells.From apoptosis experiments,the results showed that onco VV-SIKE anti-tumor through promoting cell apoptosis in MHCC97-H and U87 cell lines.The results of RT-q PCR showed that the expression level of IFNαand TNFαwas up-regulated after the infection of onco VV-SIKE in MHCC97-H cells.While the expression of IFNαin U87 cells is significantly down-regulated after the infection of onco VV-SIKE.The underlying mechanism was needed to further study.The results of tumor-bearing mice showed that onco VV-SIKE could significantly decrease the tumor size both in the U87 model and the rat C6 glioma model,furthermore,the onco VV-SIKE could prolong the life of tumor-bearing mice with U87 cells.Taken together,IKKεand TBK1 could be used as a potential target for anti-tumor treatment.Vaccinia virus carrying the physiological inhibitor gene SIKE of IKKεand TBK1 could significantly enhance the anti-tumor activity of oncolytic vaccinia virus and improve the replication ability of the virus,suggesting that onco VV-SIKE had potential applications in antitumor.This study will be very helpful in supporting the argument of the application of oncolytic vaccinia virus in tumor therapy,constituting a new therapeutic strategy for anti-tumor drugs in oncolytic vaccinia virus,and enlarging our views about the mofification of oncolytic vaccinia virus.