Mechanisms and Clinical Applications of Virus-Based Cancer Vaccines

Over the past several decades, immunotherapy as a novel cancer treatment has made tremendous progress. Several categories of immunotherapy have emerged, all designed to stimulate the patients immune system to fight cancer. Cancer vaccines, specifically virus-based cancer vaccines, is a subcategory of immunotherapy that can trigger both innate and adaptive immune response by targeting tumor-specific and tumor-associated antigens. This review summarizes the mechanisms of different types of virus-based cancer vaccines, including inactivated/live attenuated/subunit vaccines, oncolytic virus vaccines, and viral vector vaccines. Furthermore, this review introduces the clinical applications of virus-based cancer vaccines, including oncolytic virus vaccine T-VEC against metastasized melanoma, and Pexa-Vec and PROSTVAC that are currently in clinical trials. Virus-based cancer vaccines have shown encouraging results in numerous studies in enhancing overall survival, relapse-free survival, and overall response rate among patients with solid tumors. This review underscores the necessity for future research aimed at improving the efficacy of virus-based cancer vaccines and investigating combination therapies with other immunotherapies to achieve optimal treatment outcomes.