[摘 要] 目的：分析Claudin-2蛋白在食管鳞癌（esophageal squamous cell carcinoma，ESCC）组织中的表达及其与患者临床病理特征、5年生存率的关系，探索其对ESCC细胞KYSE450的增殖、迁移和侵袭的影响。方法：选取河南省肿瘤医院2010至2013年间初治的ESCC患者手术切除肿瘤组织52例及其中20例对应的癌旁组织标本，采用免疫组化和WB法检测Claudin-2的表达并分析其与患者临床病理特征和5年生存率的关系。WB法检测ESCC细胞（KYSE450、KYSE150、KYSE510、KYSE140）和人永生化食管上皮细胞SHEE中Claudin-2的表达，构建Claudin-2 shRNA慢病毒载体并转染KYSE450细胞构建敲低Claudin-2表达的细胞系，进一步通过克隆形成实验、细胞划痕实验及Transwell实验检测敲低Claudin-2对KYSE450细胞增殖、迁移和侵袭的影响。结果：ESCC组织中Claudin-2阳性率显著高于癌旁组织（P<0.05），ESCC组织中Claudin-2的表达与淋巴结转移有关（P<0.05）。Claudin-2表达阳性患者5年生存率显著低于阴性者（P<0.05）。成功构建敲低Claudin-2表达的KYSE450细胞系。sh-Claudin-2组细胞的克隆形成数、伤口愈合率和侵袭细胞数均显著低于sh-NT组和对照组（P<0.05）。结论：ESCC组织中Claudin-2的表达高于癌旁组织，且与患者5年生存率呈负相关，Claudin-2能够增强KYSE450细胞的增殖、迁移和侵袭能力。

[Abstract] Objective: To analyze the expression of Claudin-2 in human esophageal squamous cell carcinoma (ESCC) tissues and its relationship with clinicopathological characteristics and 5-year survival rate of ESCC patients, and to explore its effect on proliferation, migration and invasion of ESCC KYSE450 cells. Methods: A total of 52 cases of tumor tissues and 20 cases of corresponding para-cancerous tissues that surgically removed from ESCC patients who were primarily treated in Henan Cancer Hospital from 2010 to 2013 were collected for this study. Claudin-2 expression was analyzed by Immunohistochemistry and WB assay, and its relationship with clinicopathological characteristics and 5-year survival rate of ESCC patients was further investigated. The expression of Claudin-2 in ESCC cells (KYSE450, KYSE150, KYSE510 and KYSE140) and human immortalized esophageal epithelial SHEE cells was detected by WB assay. The Claudin-2 shRNA lentiviral vector was established and transfected into KYSE450 cells to establish a Claudin-2 knockdown cell line. Furthermore, the effects of knockdown of Claudin-2 on the proliferation, migration and invasion of KYSE450 cells were tested by clone formation experiment, cell scratch experiment and Transwell experiment. Results: The positive rate of Claudin-2 in ESCC tissues was significantly higher than that in adjacent tissues (P<0.05). The expression of Claudin-2 in ESCC tissues was related to lymph node metastasis (P<0.05). The 5-year survival rate of Claudin-2 positive patients was significantly lower than that of negative patients (P<0.05). The KYSE450 cell line with Claudin-2 knockdown was successfully constructed. The number of clone formation, wound healing rate and number of invaded cells in the sh-Claudin-2 group were significantly lower than those in the sh-NT group and the control group (all P<0.05). Conclusion: The expression level of Claudin-2 in ESCC tissues is higher than that of the tumor-adjacent tissues, and is negatively related with 5-year survival rate of ESCC patients. Claudin-2 can promote the proliferation, migration and invasion of ESCC cells.

国家自然科学基金资助项目（No.81602637）；河南省重点研发与推广专项资助项目（No. 202102310089）