Composite peptide-based vaccines for cancer immunotherapy (Review)

The use of peptide-based vaccines as therapeutics aims to elicit immune responses through antigenic epitopes derived from tumor antigens. Peptide-based vaccines are easily synthesized and chemically stable entities, and of note, they are absent of oncogenic potential. However, their application is more complicated as the success of an effective peptide-based vaccine is determined by numerous parameters. The success thus far has been limited by the choice of tumor antigenic peptides, poor immunogenicity and incorporation of strategies to reverse cancer-mediated immune suppression. In the present review, an overview of the mechanisms of peptide-based vaccines is provided and antigenic peptides are categorized with respect to their tissue distribution in order to determine their usefulness as targets. Furthermore, certain approaches are proposed that induce and maintain T cells for immunotherapy. The recent progress indicates that peptide-based vaccines are preferential for targeted therapy in cancer patients.