Immunotherapy of Oncovirus-Induced Cancers: A Review on the Development and Efficacy of Targeted Vaccines

Background: A number of viruses are oncogenic. These include the human papilloma virus (HPV), Epstein–Barr virus (EBV), Kaposi sarcoma human herpes virus 2/human herpes virus 8 (KSHHV/HHV8), hepatitis B virus, (HBV), hepatitis C virus (HCV), Merkel cell polyoma virus (McPyV), and the human T-cell leukemia virus type 1 (HTLV- 1). These viruses cause malignancies ranging from carcinomas, sarcomas, lymphomas, to leukemias. This review aims to study the effects and efficacy of vaccines against these viruses and the cancers they cause in their prevention and treatment. Methods: The literature in the past 30 years was searched employing Scopus and Google Scholar using the keywords “oncogenic viruses, HPV, EBV, KSHHV, HHV8, Polyoma virus, HTLV-1, COVID-19, carcinoma, sarcoma, lymphoma, leukemia, anti-virus vaccines”. Results: Prophylactic vaccines against the HPV and HBV are highly effective in preventing and reducing the incidence of uterine cervical and hepatocellular carcinomas. Prophylactic vaccines against other oncogenic viruses have been less successful, though efficacious in some experimental animals. Therapeutic vaccines are still mostly under evaluation and development. Conclusions: Identification of oncogenic viruses has rendered anti-viral vaccines conspicuous tools for preventing and treating cancers they cause. Many endeavors for the development of such vaccines have been met with limited success, apart from the very effective anti-HPV and anti-HBV vaccines in universal vaccination programs. With the development of new vaccine technologies, it is hoped that effective vaccines against other oncogenic viruses will be developed in the future.