Background The potency of T cell-mediated responses is a determinant of immunotherapy effectiveness in treating malignancies; however, the clinical efficacy of T-cell therapies has been limited in hepatocellular carcinoma (HCC) owing to the extensive immunosuppressive microenvironment. Objective Here, we aimed to investigate the key genes contributing to immune escape in HCC and raise a new therapeutic strategy for remoulding the HCC microenvironment. Design The genome-wide in vivo clustered regularly interspaced short palindromic repeats (CRISPR) screen library was conducted to identify the key genes associated with immune tolerance. Single-cell RNA-seq (scRNA-seq), flow cytometry, HCC mouse models, chromatin immunoprecipitation and coimmunoprecipitation were used to explore the function and mechanism of adenylate cyclase 7 (ADCY7) in HCC immune surveillance. Results Here, a genome-wide in vivo CRISPR screen identified a novel immune modulator-ADCY7. The transmembrane protein ADCY7 undergoes subcellular translocation via caveolae-mediated endocytosis and then translocates to the nucleus with the help of leucine-rich repeat-containing protein 59 (LRRC59) and karyopherin subunit beta 1 (KPNB1). In the nucleus, it functions as a transcription cofactor of CCAAT/enhancer binding protein alpha (CEBPA) to induce CCL5 transcription, thereby increasing CD8+ T cell infiltration to restrain HCC progression. Furthermore, ADCY7 can be secreted as exosomes and enter neighbouring tumour cells to promote CCL5 induction. Exosomes with high ADCY7 levels promote intratumoural infiltration of CD8+ T cells and suppress HCC tumour growth. Conclusion We delineate the unconventional function and subcellular location of ADCY7, highlighting its pivotal role in T cell-mediated immunity in HCC and its potential as a promising treatment target. Data are available on reasonable request. All data relevant to the study are included in the article or uploaded as online supplemental information.

中文翻译：

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质膜蛋白 ADCY7 的核转位增强 HCC 中 T 细胞介导的抗肿瘤免疫力


背景 T 细胞介导的反应的有效性是免疫疗法治疗恶性肿瘤效果的决定因素;然而，由于广泛的免疫抑制微环境，T 细胞疗法在肝细胞癌 （HCC） 中的临床疗效受到限制。目的 在这里，我们旨在研究导致 HCC 免疫逃逸的关键基因，并提出一种重塑 HCC 微环境的新治疗策略。设计 进行全基因组体内成簇规则间隔短回文重复序列 （CRISPR） 筛选文库，以确定与免疫耐受相关的关键基因。采用单细胞 RNA-seq （scRNA-seq）、流式细胞术、HCC 小鼠模型、染色质免疫沉淀和免疫共沉淀探讨腺苷酸环化酶 7 （ADCY7） 在 HCC 免疫监测中的功能和机制。结果 在这里，全基因组体内 CRISPR 筛选确定了一种新的免疫调节剂 ADCY7。跨膜蛋白 ADCY7 通过小窝介导的内吞作用进行亚细胞易位，然后在富含亮氨酸的重复序列蛋白 59 （LRRC59） 和核蛋白亚基 β 1 （KPNB1） 的帮助下易位到细胞核。在细胞核中，它作为 CCAAT/增强子结合蛋白 α （CEBPA） 的转录辅因子发挥作用，诱导 CCL5 转录，从而增加 CD8+ T 细胞浸润以抑制 HCC 进展。此外，ADCY7 可以外泌体形式分泌并进入邻近的肿瘤细胞以促进 CCL5 诱导。具有高 ADCY7 水平的外泌体促进 CD8+ T 细胞的肿瘤内浸润并抑制 HCC 肿瘤生长。 结论 我们描述了 ADCY7 的非常规功能和亚细胞位置，强调了其在 HCC 中 T 细胞介导的免疫中的关键作用及其作为有前途的治疗靶点的潜力。数据可应合理要求提供。与研究相关的所有数据都包含在文章中或作为在线补充信息上传。