A Novel Neoepitope Screening Platform For Generating Effective And Safe Neoantigen-Based Vaccines And Immunotherapeutics In A Hepatocellular Carcinoma Model

Immunotherapy has emerged as a novel and promising strategy for cancer treatment, while available markers for immunotherapy have poor effectiveness and safety. The advance of next-generation sequencing (NGS) technology enables us to identify tumor-specific neoantigen which could be more effective and safer for personalized immunotherapy. In this study, we demonstrated a novel workflow for the development of liver cancer personalized vaccine. Xenograft models for liver cancer were built in mice using Hepa1-6 cell lines. Tumor-specific candidate neoantigen were determined by performed whole exome sequencing (WES) and used a comprehensive bioinformatics pipeline integrating multiple factors such as MHCI-binding affinity fold change (FC), variant allele frequencies (VAFs) of somatic mutation, mRNA expression and hydrophobicity of peptides. The results showed that peptide vaccine of Gpr55 neoantigen not only triggered striking neo-antigen specific CD8 + T cell response, but also significantly inhibited the growth of tumors in both prophylactic and therapeutic models. Moreover, our results demonstrated that VAFs and FC were the effective and safety property for immunogenicity. The identified Gpr55 neoantigen was an ideal vaccine for Hepa1-6 induced xenograft models considering the immunogenicity, anti-tumor effect and safety evaluation. It was also possible to identify and develop highly effective personalized cancer vaccine by our workflow within 13 weeks. The results illustrated huge potential of tumor-specific neoantigen as a potent vaccine for clinical tumor therapy and the workflow built in this study could be used to develop more specific, safer, more effective treatments to all types of cancer patients. Note: This abstract was not presented at the meeting. Citation Format: Cheng-chi Chao, Fengjiao Yuan, Geng Liu, Guanglei Li, Bo Li, Lian Lu, Yaomei Tian, Dongli Li, Bailing Zhou, Ting An, Yingzi Fan, Chongming Jiang, Yang Shu, Honggang Lin, Heng Xu, Hanshuo Yang, Rui zhang, Xueyan Zhang, Zhen Cheng, Rong Huang, Michael Dean, Ke Men, Xiuqing Zhang, Chaoheng Yu, Jian Wang, Shuang Cheng, Huanming Yang, Yantai Wang, Yong Hou, Yuquan Wei, Li Yang. A novel neoepitope screening platform for generating effective and safe neoantigen-based vaccines and immunotherapeutics in a hepatocellular carcinoma model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-202. doi:10.1158/1538-7445.AM2017-LB-202