Abstract
For more than 100 years, an association between viral infections and the development of certain types of cancers has been well-known. Since then it has been clearly demonstrated the association between tumorigenesis and these viruses: EBV, HBV, HCV, HTLV-1, HPV, HHV-8 and MCV.
Some of these viruses are involved in oncogenesis directly, while others cause chronic infection in combination with other factors.Pathophysiology of oncogenic effect of viruses in many cases has been described at the molecular level Beside the direct effect of the viral proteins, an important role of the immune system in oncogenic effects of viruses has been emjphasized. In recent years, prevention of the these tumors formation have come to the fore.
An example of such approach is the vaccination against HBV, which has become an effective prevention of hepatocellular carcinoma. Currently, vaccination program against oncogenic viral strains of HPV is developing in the prevention of tumors of the cervix and the penis.
Further research is focused on the modification of the oncogenic effect of the virus in already infected patients and the use of viral antigens as targets of immune therapy in tumors.