MST4通过激活MAPK-ERK信号通路调节炎症因子释放促进肝癌的侵袭和转移的机制研究

MST4 upregulates secretion of inflammatory factors via activation of MAPK-ERK signaling pathway and promotes invasion and metastasis of hepatocellular carcinoma

背景与目的:丝氨酸/苏氨酸蛋白激酶4(mammalian Ste20-like kinase 4,MST4)促进肿瘤的侵袭和转移,前期研究发现,MST4可以通过上皮间质转化促进肝癌细胞的侵袭和转移。该研究旨在探讨MST4通过激活丝裂原活化蛋白激酶信号通路-细胞外信号调节激酶(mitogen-activated protein kinaseextracellular signal-regulated kinase,MAPK-ERK)信号通路影响炎症因子释放调节炎症微环境,促进肝癌的侵袭和转移。方法:采用实时荧光定量聚合酶链反应(real-time fluorescent quantitative polymerase chain reaction,RTFQ-PCR)方法对MST4高表达的肝癌细胞中白介素1β(interleukin-1β,IL-1β)、白介素6(interleukin-6,IL-6)、肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)和趋化因子2(CC chemokine ligand-2,CCL2)的转录水平进行检查,通过蛋白[质]印迹法(Western blot)和酶联免疫吸附测定法(enzyme-linked immune sorbent assay,ELISA)研究MST4对肝癌细胞分泌炎症因子IL-1β、IL-6、TNF-α和CCL2蛋白量的表达及活性的影响。结果:MST4高表达的肝癌细胞,其IL-1β、IL-6、TNF-α和CCL2的转录水平、蛋白水平和分泌水平显著高于MST4低表达的肝癌细胞系(P<0.05)。同时发现MST4可以通过改变ERK磷酸化的水平,促进细胞因子释放的改变。结论:MST4可以通过MAPK-ERK信号通路活化完成对肿瘤细胞分泌炎症因子的调节,促进炎症因子的分泌,增强肝癌细胞侵袭和转移的能力。

Background and purpose： It has been reported that mammalian Ste20-1ike kinase 4 （MST4） promotes the invasion and metastasis of tumors. In the previous research, we found that MST4 promoted invasion and metastasis of liver cancer through epithelial-mesenchymal transition. In this study, we explored the effect of MST4 on promoting the invasion and metastasis of hepatocellular carcinoma （HCC） cells by activating MAPK-ERK signaling pathway and inflammatory factors. Methods： We used real-time fluorescence quantitative polymerase chain reaction （R.TFQ-PCR） to detect the transcription of IL-1β, IL-6, TNF-α and CCL2 in different HCC cell lines expressing MST4 differently. Then we studied the different secretion of IL-11~, IL-6, TNF-α and CCL2 in cells using Western blot and enzyme-linked immunosorbent assay （ELISA）. Results： The RNA transcription and protein translation levels of IL-1β, IL-6, TNF-α and CCL2 were significantly higher in HCC cell line with high expression of MST4 than those in the HCC cell line with lower expression of MST4 （P〈0.05）. We found that MST4 could change the level of phosphorylation of ERK to promote secretion of inflammatory cytokines. Conclusion： High expression of MST4 can upregulate the secretion of inflammatory factors （IL-1β, IL-6, TNF-α and CCL2） in HCC cells and enhance the ability of invasion and metastasis of HCC cells, through activating the MAPK-ERK signaling pathway.