肿瘤免疫原性可以影响免疫治疗的敏感性和应答率。基因突变导致的肿瘤突变负荷增加是提高免疫原性的重要因素之一，但其具体调控机制尚不明确。我们前期在肝癌病例中通过全外显子组测序筛选到DHX34第251位（K251M）存在突变，且DHX34突变肽可促进T细胞活化。生物信息学分析表明DHX34高表达与肝癌病人生存期负相关，与炎性细胞浸润、炎性因子、趋化因子分泌负相关。因此我们假设DHX34突变可以调控肝癌免疫原性，提高免疫负调控抗体治疗的敏感性和响应率。本项目拟首先通过流式细胞术、免疫印迹等技术体外研究DHX34 K251M在肝癌细胞中的生物学和免疫学功能。其次，运用RNA-seq、蛋白芯片、免疫共沉淀等技术在体外阐明DHX34 K251M的作用靶点及信号通路，最后利用基因敲除鼠模型进一步体内明确DHX34 K251M增强免疫负调控抗体治疗敏感性的作用。本项目将为肝癌免疫治疗提供理论基础和治疗靶点。

Abstract：Tumor immunogenicity can affect the sensitivity and response rate of tumor immunotherapy. Gene mutation will improve tumor mutation burden（TMB）and play key roles in enhancing immunogenicity，however the regulation mechanism is still unclear。In previous study we found the 251 amino (K251M) in DHX34 was mutated and mutated peptide can promote T cell to secrete IFN-γin vitro. Further bioinformatics analysis showed that DHX34 was highly expressed in liver cancer and it is negatively correlated with the secretion of inflammatory cytokines and chemokines，the infiltration of immune cells. Based on above we supposed DHX34 mutation can influence the immunogenicity of live cancer and improve the sensitivity and response rate immune antibody negative regulation. Our project will illustrate the biology and immunology function of DHX34 K251M by flow cytometry and liduid phase chip technologies in vitro. Second, we will discover signaling pathway, downstream targets of DHX34K251M mutation in regulating the immunogenicity of liver cancer by RNA-seq, protein microarray, co-immune precipitation in vitro. Finally we will clear the role of DHX34K251M mutation in enhancing the sensitivity and clinical value of immune negative antibody therapy by using knockout mice models in vivo. Our project will provide the theoretical basis and target for liver caner immunotherapy.