Cancer vaccine: a promising strategy in tumor immunotherapy

Abstract

Tumor immunotherapy, through active or passive immunization, improves the immune responsiveness to existed tumors and exhibits effective antitumor effects.Cancer vaccines could amplify antitumor immune responses in patients through active immunization and play important roles in tumor immunotherapy.The types of cancer vaccines include peptide vaccines, viral or bacterial vector vaccines, nucleic acid vaccines and dendritic cell vaccines.Generally, low clinical response rates of cancer vaccines were observed in many clinical trials.The main reasons might be due to the unsuitable target antigens used in the cancer vaccines, and due to the immunosuppressive tumor microenvironment.The neoantigens derived from somatic mutations in tumors are not subjected to thymic selection and have potent immunogenicity, therefore can serve as the preferred target antigens in cancer vaccines.The clinical successes of immune checkpoint blockers make the immune system possible to be normalized and the anti-tumor effects restored.With the development of next-generation-sequencing technology and bioinformatic algorithm, neoantigens could be discovery and personalized cancer vaccines are developed.In combination with immune checkpoint blockers or other immunotherapies, the cancer patients may benefit more from the personalized cancer vaccines. Key words: Cancer vaccine; Tumor antigen; Personalized vaccine; Tumor microenvironment