[Oncolytic poxviruses]

Abstract

The latest data on selection and construction of poxviruses capable of specifically lysing tumor cells of different genesis, inducing antitumor immunity and apoptosis of malignant cells are discussed. The review concerns several directions: virus attenuation, insertion of immunomodulatory protein genes, and anti-tumor protein genes. Thymidine kinase and viral growth factor genes make the greatest contribution to the virus attenuation as their inactivation results in the virus inability to replicate in non-dividing cells, thereby contributing to increased selectivity with respect to tumor cells. Among the immunomodulatory proteins, interleukins 2, 12, and granulocyte-macrophage colony-stimulating factor proved to be most promising for oncolytic virotherapy. An attempt to use p53 protein gene expressed by vaccinia virus for addressed apoptosis of tumor cells was reported. The use of the double and triple viral recombinants carrying genes of multidirectional action seems to be most promising. Encouraging results were obtained using vaccinia virus in the oncotherapy with prodrugs and angiogenesis inhibitors. At present, two poxviral strains are undergoing Phase III clinical trials as anti-tumor preparations in the USA.