下调METTL5通过Wnt/β-catenin信号通路抑制三阴乳腺癌细胞增殖、迁移与侵袭

Down-regulation of METTL5 inhibits proliferation,migration and invasion of triple-negative breast cancer cells through Wnt/β-catenin signaling pathway

目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。

Aim To investigate the role and potential mechanism of methyltransferase-like 5(METTL5)in triple-negative breast cancer(TNBC).Methods The expression of METTL5 in TNBC tumor tissues and cell lines was detected by immunohistochemistry and Western blot.After shRNA targeting METTL5(shRNA-METTL5)was transfected into TNBC cells,cell proliferation,migration and invasion were detected by CCK-8,colony formation,wound healing and Transwell assays,respectively.Western blot was used to detect the expression of Wnt/β-catenin signaling-related key proteins.A xenograft tumor model was constructed to verify the effect of METTL5 knockdown on the growth of TNBC cells and Wnt/β-catenin signaling activity in vivo.Results The expression of METTL5 was up-regulated in TNBC tumor tissues and cell lines(P<0.01).Knockdown of METTL5 significantly inhibited the proliferation,migration and invasion of TNBC cells and reduced the expression of Wnt/β-catenin signaling moleculesβ-catenin,cyclin D1,matrix metalloproteinase(MMP)-2 and MMP-7(all P<0.01).Knockdown of METTL5 reduced tumor growth and Wnt/β-catenin signaling activity in vivo.Conclusions Knockdown of METTL5 can inhibit the proliferation,migration and invasion of TNBC cells,which may be related to the inhibition of Wnt/β-catenin signaling pathway.