Neoantigens represent a class of short peptides with changed amino acid sequence because of somatic mutations in cancer cells. Importantly, neoantigens can be bond and presented on the cell surface by human leukocyte antigen (HLA), subsequently being recognized by T-cell receptors (TCRs) to activate the immune system to attack specific cancer cells. In light of their immunogenicity and little expression in normal tissues, therefore neoantigens are considered as one of promising targets for cancer immunotherapy as personalized cancer vaccines [1-4]. Moreover, it was reported that the combination of neoantigens and checkpoint blockade therapy showed significant efficacy in melanoma treatment [5,6]. So far, a large number of potential neoantigen has been discovered through proteogenomics in the discovery and validation of tumor neoantigen, but there is no a comprehensive database of tumor neoantigen.
    To end it, through mining neoantigen-related literatures on PubMed and cancer immunity peptide related databases, we constructed the first database named “dbPepNeo”, which collects substantial validated HLA-I binding neoantigens for multiple human tumors, such as melanoma, pancreatic cancer, non-small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, chronic lymphocytic leukemia, acute myeloid leukemia, esophageal cancer, neuroblastoma, multiple myeloma, squamous cell carcinoma, renal cell carcinoma and diffuse intrinsic pontine glioma. In dbPepNeo, all neoantigens are classified into three categories: (1) a total of 407,794 low confidence neoantigen peptides were just examined by mass spectrometry (MS); (2) 247 medium confidence neoantigens peptides containing somatic mutations were verified by MS and whole-exome sequencing; (3) 295 high confidence neoantigens were validated to be immunogenic by specific T-cell response. In addition, an online customized proteogenomic workflow for neoantigen prediction and selection was provided, namely “ProGeo-neo” developed by our team.
    In summary, our research aims at providing a platform to discover potential targets for neoantigen-based cancer immunotherapy, thereby further guiding scientists and clinicians searching for rigorous cancer vaccines.