已有多项研究报道了CLCN4在肿瘤进展中的作用，然而其机制仍需进一步研究。本研究的目的是在更好地理解其病理机制的基础上，探索CLCN4在子宫内膜癌（UCEC）中的潜在致病作用。根据癌症基因组图谱（TCGA），分析了CLCN4在不同肿瘤中的潜在作用，包括表达差异、突变、生存、病理分期、免疫亚型、免疫浸润、肿瘤微环境（TME）、肿瘤突变负荷（TMB）、微卫星不稳定性（MSI）以及错配修复（MMR）相关性。然后，分析了CLCN4在UCEC中的表达、预后、突变和功能富集。采用免疫组织化学实验验证了CLCN4在子宫内膜癌组织和正常组织中的表达。体外实验中，我们通过沉默HEC-1-A细胞中的CLCN4，并进行细胞增殖、迁移、侵袭等CCK8、WB、RT-PCR、缺口愈合、Transwell实验进行分子功能验证。结果显示，TCGA的20种癌症类型中均观察到CLCN4的高表达。CLCN4的表达与MESO、BLCA、THCA以及特别是UCEC的不良生存相关。CLCN4的表达与CD4+ T细胞浸润，特别是CD4+ Th1细胞密切相关。免疫组织化学实验证明CLCN4在子宫内膜肿瘤中高表达，体外实验证明CLCN4的沉默抑制了细胞的增殖、迁移和侵袭。本研究首次全面了解了CLCN4在不同肿瘤中的致癌作用，CLCN4可能成为UCEC中的潜在生物标志物。

Several studies have reported the role of CLCN4 in tumor progression. However, its mechanism remains to be thoroughly studied. The objective of this study was to explore the potential pathogenic role of CLCN4 in endometrial carcinoma (UCEC) with a better understanding of the pathological mechanisms involved. The potential roles of CLCN4 in different tumors were explored based on The Cancer Genome Atlas (TCGA), the expression difference, mutation, survival, pathological stage, Immunity subtypes, Immune infiltration, tumor microenvironment (TME), tumor mutation burden (TMB), microsatellite instability (MSI), mismatch repair (MMR) related to CLCN4 were analyzed. Then, the expression, prognosis, mutation, and functional enrichment of CLCN4 in UCEC were analyzed. Immunohistochemical experiment was used to verify the expression of CLCN4 in endometrial cancer tissues and normal tissues. In vitro, we knocked down of CLCN4 in HEC-1-A cells and performed CCK8, WB, RT-PCR, wound-healing, transwell assays to further validation of the molecular function. Results revealed that high expression of CLCN4 was observed in 20 cancer types of TCGA. CLCN4 expression correlates with poor survival in MESO, BLCA, THCA, especially UCEC tumors. CLCN4 expression was significantly associated with CD4+ T-cell infiltration, especially CD4+ Th1-cell. Immunohistochemical experiment reveals that CLCN4 is high expressed in endometrial tumors, in vitro experiment reveals that knockdown of CLCN4 inhibits the cells proliferation, migration and invasion. Our study is the first to offer a comprehensive understanding of the oncogenic roles of CLCN4 on different tumors. CLCN4 may become a potential biomarker in UCEC.