[摘 要] 目的：探讨miR-7-5p调控叉头框转录因子M1（FOXM1）对食管鳞状细胞癌（ESCC）KYSE-150细胞增殖、凋亡和免疫 逃逸的影响。方法：通过双萤光素酶报告基因实验验证miR-7-5p与FOXM1的靶向结合位点。收集2022年1月至2024年10月 期间苏州大学附属常州老年病医院收治的56例ESCC患者的癌组织和癌旁组织标本，以及患者的基本临床资料。采用qRT-PCR 法检测ESCC组织中miR-7-5p和FOXM1的表达水平，分析其表达与临床病理特征的关系。常规培养的KYSE-150细胞为Ctrl 组，用Lipofectamine 3000 转染试剂将质粒转染KYSE-150细胞，分为Mimic NC组、miR-7-5p mimic组、miR-7-5p mimic + OE-NC 组和miR-7-5p mimic + OE-FOXM1组。EdU染色和CCK-8实验检测KYSE-150细胞增殖能力，流式细胞术检测KYSE-150细胞 的凋亡和CD8+ T细胞凋亡情况，WB法检测KYSE-150细胞中PD-L1、FOXM1、BAX和PCNA蛋白的表达。构建KYSE-150细胞 裸鼠移植瘤模型，观察 miR-7-5p 过表达对移植瘤生长和组织中 Ki-67、FOXM1 表达的影响。结果：miR-7-5p 可以靶向负调控 FOXM1（P < 0.05）。ESCC组织中miR-7-5p呈低表达，FOXM1呈高表达（均P < 0.05），其表达分别与TNM分期、分化程度显著相 关联（均P < 0.05）。miR-7-5p过表达组EdU阳性细胞率、细胞增殖能力、CD8＋ T细胞凋亡率，以及PD-L1、PCNA、FOXM1 mRNA 和蛋白均显著降低（均P < 0.05），细胞凋亡率、miR-7-5p、BAX水平均显著升高（均P < 0.05）；同时过表达 FOXM1则可逆转上 述作用（均P < 0.05）。miR-7-5p过表达可降低小鼠移植瘤质量和体积，以及移植瘤组织中Ki-67、FOXM1蛋白的表达（均P < 0.05）。 结论：miR-7-5p过表达能够显著抑制KYSE-150细胞增殖和免疫逃逸并促进细胞凋亡，其机制可能是通过靶向负调控FOXM1基 因实现的。

[Abstract] Objective: To investigate the effects of miR-7-5p on the proliferation, apoptosis, and immune escape of esophageal squamous cell carcinoma (ESCC) KYSE-150 cells by regulating forkhead box M1 (FOXM1). Methods: The targeted binding sites of miR-7-5p and FOXM1 were verified by the dual-luciferase reporter gene assay. The cancer tissues and adjacent paracancerous tissues as well as the basic clinical data of 56 ESCC patients hospitalized at Changzhou Geriatric Disease Hospital affiliated to Soochow University between January 2022 and October 2024 were collected. qRT-PCR was used to detect the expression levels of miR-7-5p and FOXM1 in ESCC tissues, and analyze the relationship between their expressions and clinicopathological characteristics. Normal cultured KYSE-150 cells were selected as the Control group Plasmids were transfected into KYSE-150 cells using Lipofectamine 3000 transfection reagent, and the cells were assigned into the Mimic-NC group, the miR-7-5p mimic group, the miR-7-5p mimic + OE-NC group, and the miR-7-5p mimic + OE-FOXM1 group. EdU staining and CCK-8 assay were used to detect the proliferation ability of KYSE-150 cells. Flow cytometry was performed to detect the apoptosis of KYSE-150 cells and CD8+ T cells. Western blot assay was performed to detect the expression levels of PD-L1, FOXM1, BAX, and PCNA proteins in KYSE-150 cells. A nude mouse transplanted tumor model of KYSE-150 cells was established to observe the effects of miR-7-5p overexpression on the growth of the transplanted tumors and the expressions of Ki-67 and FOXM1 in the tissues. Results: miR-7-5p could target and negatively regulate FOXM1 (P < 0.05). miR-7-5p expression was low and FOXM1 expression was high in ESCC tissues (both P < 0.05). The expressions of miR-7-5p and FOXM1 were significantly correlated with TNM stage and differentiation degree, respectively (all P < 0.05). The rates of EdUpositive cells, cell proliferation ability, CD8+ T cell apoptosis rate, as well as PD-L1, PCNA, and FOXM1 mRNA and protein in the miR-7-5p overexpression group were significantly reduced (all P < 0.05), while the apoptosis rate, miR-7-5p, and BAX increased significantly (all P < 0.05). Meanwhile, overexpression of FOXM1 could reverse the above effects (all P < 0.05). Overexpression of miR-7-5p decreased the mass and volume of transplanted tumors, and the expressions of Ki-67 and FOXM1 proteins in transplanted tumor tissues (all P < 0.05). Conclusion: Overexpression of miR-7-5p can significantly inhibit the proliferation and immune escape of KYSE-150 cells and promote cell apoptosis, which may be achieved by targeted negative regulation of FOXM1.

[基金项目] 江苏省科学技术厅项目（No. 202203250）