Progress in gene therapy using oncolytic vaccinia virus as vectors

Background Vaccinia virus was widely used in the World Health Organization's smallpox eradication campaign and is currently a promising vector for gene therapy owing to its unique characteristics. Vaccinia virus can selectively replicate and propagate productively in tumor cells, resulting in oncolysis. In addition, rapid viral particle production, wide host range, large genome size (approximately 200 kb), and safe handling render vaccinia virus a suitable vector for gene therapy. Materials and methods Cancer vaccines and gene therapy are being studied in clinical trials and experiment researches. However, we put forward unique challenges of optimal selection of foreign genes, administration and modification of VACV, personalized medicine, and other existing problems, based on current researches and our own experiments. Conclusion This review presents an overview of the vaccinia virus from its mechanisms to medical researches and clinical trials. We believe that the solution to these problems will contribute to understanding mechanisms of VACV and provide a theoretical basis for clinical treatment.