[摘 要] 目的：探讨2',4'-二羟基查尔酮（D2）通过调控miR-7-5p诱导自噬，抑制结直肠癌细胞增殖、迁移及上皮间质转化 （EMT）的分子机制。方法：选取结直肠癌细胞系HCT-15、SW620为研究对象，分别用不同浓度（0、12.5、25、50 μmol/L）的D2处 理细胞，采用MTT法和平板克隆实验检测细胞增殖活力及克隆形成能力，划痕愈合实验及Transwell实验评估细胞迁移能力，WB 法检测EMT相关蛋白、自噬相关蛋白及PI3K/AKT/mTOR信号通路蛋白的表达情况，免疫荧光染色法观察自噬小体的形成。基 于TCGA数据库分析miR-7-5p在结直肠癌中的表达水平，并借助KEGG富集分析探究miR-7-5p与结直肠癌的关联。运用 RT-qPCR检测miR-7-5p的表达量，同时采用慢病毒转染技术构建miR-7-5p稳定敲低或过表达的细胞系。结果：D2抑制结直肠 癌细胞的增殖、迁移及EMT进程（P < 0.05或P < 0.01）。TCGA数据库分析及KEGG富集分析显示，miR-7-5p在结直肠癌中呈低 表达，且与结直肠癌的发生有密切关联。12.5、25、50 μmol/L D2处理均可上调HCT-15、SW620细胞miR-7-5p的表达水平（均 P < 0.01）。25 μmol/L D2处理组HCT-15、SW620细胞中 LC3、p-ULK1等自噬相关蛋白表达增加，而PI3K/AKT/mTOR信号通路 受到抑制（均P < 0.05），细胞内自噬小体数量增加（均P < 0.01）；与D2单独处理组相比，经 D2处理的miR-7-5p敲减细胞中LC3、 p-ULK表达量有所下降（P < 0.05或P < 0.01）。结论：D2通过调控miR-7-5p诱导自噬，抑制结直肠癌细胞的增殖、迁移及EMT 进程，其机制可能与抑制PI3K/AKT/mTOR信号通路有关。

[Abstract] Objective: To investigate the molecular mechanism by which 2', 4'-dihydroxychalcone (D2) inhibits proliferation, migration, and epithelial-mesenchymal transition (EMT) in colorectal cancer cells through miR-7-5p-mediated autophagy. Methods: Human colorectal cancer cell lines HCT-15 and SW620 were treated with D2 at concentrations of 0, 12.5, 25, and 50 μmol/L. Cell proliferation and clonogenic capacity were evaluated using MTT and colony formation assays. Cell migration was assessed by wound healing and Transwell assays. WB assay was used to detect the expression of EMT-related proteins, autophagy-related proteins, and key components of the PI3K/AKT/mTOR pathway. Autophagosome formation was visualized by immunofluorescence staining. TCGA database and KEGG pathway analyses were performed to evaluate miR-7-5p expression and its association with colorectal cancer. RT-qPCR was used to quantify miR-7-5p expression, and lentiviral transduction was employed to establish stable miR-7-5p knockdown or overexpression cell lines. Results: D2 significantly inhibited colorectal cancer cell proliferation, migration, and EMT (P < 0.05 or P < 0.01). TCGA and KEGG analyses revealed that miR-7-5p expression was downregulated in colorectal cancer and closely associated with disease progression. D2 treatment (12.5, 25, and 50 μmol/L) significantly upregulated miR-7-5p expression in HCT-15 and SW620 cells (P < 0.01). At 25 μmol/L, D2 increased the expression of autophagy-related proteins (LC3 and p-ULK1) and inhibited the PI3K/ AKT/mTOR signaling pathway (P < 0.05), accompanied by increased autophagosome formation (P < 0.01). In miR-7-5p-knockdown cells treated with D2, the levels of LC3 and p-ULK1 were significantly reduced compared to D2-only treated cells (P < 0.05 or P < 0.01). Conclusion: D2 upregulates miR-7-5p to induce autophagy, thereby inhibiting colorectal cancer cell proliferation, migration, and EMT, possibly through suppression of the PI3K/AKT/mTOR signaling pathway.

[基金项目] 国家自然科学基金项目（No. 82260678）;吉林省科技厅项目（No. YDZJ202201ZYTS173）