Neoepitope-Based Cancer Vaccines: Principle and Applications

It has been known that different cancers can elicit host immune responses that are highly specific for any given tumor. This high level of specificity stems from the fact that cancers arise due to mutations (both passenger and driver mutations) that ultimately give rise to mutated peptides that are seen as “non-self” by the adaptive immune compartment. Therefore, tumors are immunogenic, and the mutated peptides encoded by tumor-specific mutations and presented on surface of tumor cells, called neoantigens which are a source of their immunogenicity. Precise identification and prediction of neoantigens using advanced high-throughput gene sequencing and bioinformatic approaches have significantly amplified the probability of success of neo-antigen-based vaccines. Further, neoantigen-based vaccines are in many clinical trials showing promising results. However, many important concerns need to be addressed before neoantigen-based vaccines evolve as a major form of cancer immunotherapy. Here, we will discuss the prospects and major challenges that lie ahead.