辣椒碱通过激活结肠癌细胞NLRP3炎性小体进而促进结肠癌转移的分子机制研究

The Molecular Mechanism of the Promotion Effect of Capsaicin on the Colon Cancer Cell Metastasis by Activating the Inflammatory Corpuscle NLRP3

目的研究辣椒碱促进结肠癌转移的作用及其机制是否与NLRP3炎性小体的活化有关。方法通过酶联免疫吸附实验检测辣椒碱对结肠癌SW480和HCT116细胞的炎症相关分子IL-1β、IL-6及TNF-α的表达;采用蛋白质免疫印迹检测辣椒碱对结肠癌SW480细胞和HCT116细胞内NLRP3和EMT相关标志性蛋白的变化;采用Tanswell检测辣椒碱和MCC950共处理后结肠癌细胞迁移能力的变化;通过免疫印迹检测辣椒碱处理结肠癌细胞SW480和HCT116与NLRP3特异性抑制剂MCC950分别共处理结肠癌后,NLRP3和EMT相关标志性蛋白的变化;通过流式细胞仪检测ROS抑制剂NAC处理结肠癌细胞后胞内ROS的变化。结果辣椒碱处理结肠癌细胞SW480和HCT116后,胞内炎性因子明显上升,NLRP3表达量增加,同时上调间质样标志物Vimentin的表达,下调上皮样标志物E-cadherin表达。但用NLRP3特异性抑制剂MCC950处理细胞之后,炎性因子表达量下调,NLRP3蛋白水平和EMT现象也被明显抑制。而MCC950处理后能抑制辣椒碱增加的细胞迁移数量。ROS抑制剂NAC能逆转辣椒碱诱导结肠癌细胞NLRP3的蛋白水平。结论辣椒碱通过促进结肠癌细胞内ROS的表达水平来激活NLRP3炎性小体,进而促进结肠癌细胞的转移。

Objective To explore whether the promotion effect of capsaicin on the colon cancer cell metastasis and its mechanism are correlated with the activation of the inflammatory corpuscle NLRP3. Methods The expression of the inflammation-related molecules IL-1β, IL-6 and TNF-α in the colon cancer cells SW480 and HCT116 was detected by the enzyme-linked immunosorbent assay. The changes of the NLRP3 and EMT related proteins in the cells of SW480 and HCT116 were determined by Western Blot. The changes in the migration ability of colon cancer cells after the treatment with capsaicin and MCC950 were assayed by Transwell. The changes of the NLRP3 and EMT related proteins were detected by Western Blot after the cells of SW480 and HCT116 were treated with capsaicin and the NLRP3 specific inhibitor MCC950 respectively. The changes of ROS were detected by Flow Cytometer after the colon cancer cells were treated with the ROS inhibitor NAC. Results After the cells SW480 and HCT116 were incubated with capsaicin, the expression levels of inflammatory cytokines and NLRP3 were up-regulated significantly and the mesenchymal marker Vimentin was also up-regulated, while the epithelial cell marker E-cadherin was down-regulated. However, the expression of inflammatory cytokines, NLRP3 and EMT were inhibited by the NLRP3 specific inhibitor MCC950, which also inhibited the increase of the cell migration count induced by capsaicin. The ROS inhibitor NAC reversed the capsaicin-induced protein level of NLRP3 in the colon cancer cells. Conclusion Capsaicin promotes the colon cancer cell metastasis by increasing the expression of ROS in the colon cancer cells to activate the inflammatory corpuscle NLRP3.