B淋巴细胞在舌癌中的浸润情况及功能机制尚未有明确报道，本项目前期发现舌癌中存在明显的B淋巴细胞浸润，鉴定了可能为舌癌特异性的CD19+CD5+CD24-CD27+CD38hiCD1dhi B淋巴细胞亚群，伴淋巴毒素表达上调，清除B淋巴细胞可抑制小鼠舌癌移植瘤生长；舌癌组织存在缺氧现象和CXCL13表达，舌癌细胞缺氧创建微环境可诱导B淋巴细胞表型和功能转换。本项目拟首先进一步鉴定舌癌浸润性B淋巴细胞的标志和功能分子表型，明确舌癌细胞缺氧微环境诱导B淋巴细胞浸润和表型转换机制；其次，验证浸润性B淋巴细胞通过淋巴毒素活化STAT3信号促进舌癌生长；再次，揭示mTOR调控线粒体自噬介导的代谢重编程参与浸润性B淋巴细胞的促癌功能；最后，通过建立PDX联合B淋巴细胞过继移植小鼠模型和临床组织标本检测分析B淋巴细胞在舌癌生长中的作用。本项目的完成将为探讨舌癌生长的新机制和舌癌防治的新干预策略提供新思路。

The infiltration pattern of B lymphocytes in tongue cancer and their roles and mechanisms have not been clearly reported. We previously found obvious infiltration of B lymphocytes in tongue cancer (TC), accompanied with increased lymphotoxin expression. B lymphocytes deletion inhibited the mouse TC growth in vivo. Hypoxia is common in TCs cells with CXCL13 upregulation. Established environment by TC cells hypoxia promoted the phenotype and function transition of B lymphotoxin. In the present program, first, we will further identify the subset of B lymphocyte in TC and confirm the role and mechanism of the environment established by TC cells hypoxia in function transition of B lymphocytes. Then, we will confirm infiltrating B lymphocytes directly promote TC growth via lymphotoxin activated STAT3 signaling in TC cells. Third, we will reveal the metabolic reprogramming mediated by mTOR regulated mitophagy was involved in tumor-promoting activity of B lymphocytes. Finally, we will confirm the role of B lymphocytes in TC via PDX models combined with adoptive transfer of B lymphocytes, and the detection on clinical samples. The completion of this program will provide new clues for the mechanisms study for TC growth and the development of new intervention strategies for the prevention and treatment of TC.