雷公藤甲素调控p53/SLC7A11轴诱导结肠癌细胞铁死亡

目的 探讨雷公藤甲素调控p53/SLC7A11轴诱导结肠癌细胞铁死亡的分子机制。方法 培养人结肠癌细胞系（HCT116），采用CCK-8法检测细胞活力，EdU实验和平板克隆形成实验检测细胞增殖与克隆能力；铁死亡相关检测试剂盒测定Fe2+离子、谷胱甘肽（GSH）、丙二醛（MDA）含量，流式细胞术检测活性氧自由基（ROS）水平；JC-1荧光探针检测细胞线粒体膜电位变化；Western Blot 检测p53、SLC7A11蛋白表达水平。结果 CCK-8实验显示雷公藤甲素呈浓度梯度依赖性抑制结肠癌细胞活力，其IC50为47.82nmol/L；EdU实验和平板克隆形成实验证实雷公藤甲素可显著抑制结肠癌细胞增殖与克隆能力（P<0.05）；在雷公藤甲素干预后，铁死亡相关指标检测发现，HCT116细胞 Fe2+离子、MDA及ROS水平显著升高，GSH含量降低（P<0.05）；并在荧光显微镜下观察到HCT116细胞线粒体膜电位下降（P<0.05）。进一步通过Western Blot实验，发现HCT116细胞p53蛋白表达增加，SLC7A11蛋白表达下调（P<0.05）。结论 雷公藤甲素可通过调控p53/SLC7A11轴诱导结肠癌细胞铁死亡，抑制结肠癌细胞增殖与克隆。

Triptolide regulating the p53 / SLC7A11 axis induces ferroptosis in colon cancer cells

Objective To investigate the molecular mechanism of triptolide in regulating the p53 / SLC7A11 axis-induced ferroptosis in colon cancer cells. Methods Human colon cancer cell line (HCT116) was cultured, the cell viability was detected by CCK-8 assay, and the cell proliferation and cloning ability were detected by EdU assay and plate cloning formation assay. The contents of Fe2+ ions, glutathione (GSH) and malondialdehyde (MDA) were determined with ferroptosis related detection kit, and reactive oxygen species (ROS) were detected by flow cytometry. The changes of mitochondrial membrane potential were detected by JC-1 fluorescent probe. The protein expression levels of p53 and SLC7A11 were detected by Western Blot. Results CCK-8 experiments showed a concentration of triptolide gradient-dependent inhibition of colon cancer cell viability, Its IC50 is 47.82nmol/L. EdU experiments and plate clone formation experiments confirmed that triptolide significantly inhibited colon cancer cell proliferation and clonal capacity (P<0.05). After the triptolide intervention, ferroptosis-related indicators detection found that, significant higher levels of Fe2+ ions, MDA, and ROS in HCT116 cells, GSH content reduction (P<0.05). A decreased mitochondrial membrane potential in HCT116 cells was also observed under a fluorescence microscope (P<0.05). Further, Western Blot experiments showed that p53 protein expression was increased, and SLC7A11 protein expression was downregulated in HCT116 cells (P<0.05). Conclusion Triptolide can induce colon cancer cell ferroptosis and inhibit colon cancer cell proliferation and cloning by regulating the p53 / SLC7A11 axis.