目的:Mitofusin-2(MFN2)是一种线粒体膜蛋白,在调节线粒体融合和细胞代谢中起关键作用。为了进一步阐明MFN2的影响,本研究旨在探讨其对肝细胞癌(HCC)细胞功能的意义及其在介导化疗敏感性中的潜在作用。
方法:本研究调查了沉默和过表达MFN2对存活的影响,扩散,入侵和迁移能力,和索拉非尼对MHCC97-L肝癌细胞的耐药性。使用XAV939(β-连环蛋白抑制剂)和HLY78(β-连环蛋白激活剂)进行另外的实验以进一步验证这些发现。
结果:沉默MFN2可显著促进MHCC97-L细胞的存活和增殖,增强了他们的入侵和迁移能力,增加了索拉非尼的IC50,减少了TUNEL阳性细胞的百分比,并降低促凋亡蛋白的表达。此外,沉默MFN2显著诱导β-catenin的核易位,增加β-连环蛋白乙酰化水平,增强下游调节蛋白Snail1和波形蛋白的表达,同时抑制E-cadherin表达。相反,过表达MFN2逆转了上述MHCC97-L细胞中观察到的效应。结果证实沉默MFN2激活了β-catenin/上皮间质转化(EMT)通路,降低了细胞对索拉非尼的敏感性,可以通过XAV939治疗逆转。相反,MFN2过表达抑制β-catenin/EMT通路,增加细胞对索拉非尼的敏感性,这可以被HLY78改变。
结论:肝癌细胞MFN2低表达促进β-catenin的核转位,从而激活EMT途径并介导对索拉非尼的抗性。
OBJECTIVE: Mitofusin-2 (MFN2) is a mitochondrial membrane protein that plays a critical role in regulating mitochondrial fusion and cellular metabolism. To further elucidate the impact of MFN2, this study aimed to investigate its significance on hepatocellular carcinoma (HCC) cell function and its potential role in mediating chemosensitivity.
METHODS: This study investigated the effects of silencing and overexpressing MFN2 on the survival, proliferation, invasion and migration abilities, and sorafenib resistance of MHCC97-L HCC cells. Additional experiments were conducted using XAV939 (a β-catenin inhibitor) and HLY78 (a β-catenin activator) to further validate these findings.
RESULTS: Silencing MFN2 significantly promoted the survival and proliferation of MHCC97-L cells, enhanced their invasion and migration capacities, increased the IC50 of sorafenib, reduced the percentage of TUNEL-positive cells, and decreased the expression of proapoptotic proteins. Additionally, silencing MFN2 markedly induced the nuclear translocation of β-catenin, increased β-catenin acetylation levels and enhanced the expression of the downstream regulatory proteins Snail1 and Vimentin while inhibiting E-cadherin expression. Conversely, overexpressing MFN2 reversed the effects observed in MHCC97-L cells mentioned above. The results confirmed that silencing MFN2 activated the β-catenin/epithelial-mesenchymal transition (EMT) pathway and reduced the sensitivity of cells to sorafenib, which could be reversed by XAV939 treatment. Conversely, overexpression of MFN2 inhibited the β-catenin/EMT pathway and increased the sensitivity of cells to sorafenib, which could be altered by HLY78.
CONCLUSIONS: Low expression of MFN2 in HCC cells promotes the nuclear translocation of β-catenin, thereby activating the EMT pathway and mediating resistance to sorafenib.