miR-145-5p靶向TPM3通过ERK信号通路抑制甲状腺癌TPC-1细胞侵袭和转移

目的探讨miR-145-5p对甲状腺癌细胞侵袭和转移的影响。方法将miR-145-5p mimic质粒、mimic-NC质粒、TPM3质粒分别或联合转入甲状腺癌细胞,RT-qPCR检测miR-145-5p与TPM3 mRNA的表达,双荧光素酶报告检测靶向关系,Transwell法检测细胞侵袭能力,划痕实验检测细胞迁移能力,Western blot检测ERK1/2和p-ERK1/2的表达;采用裸鼠右后肢腹侧皮下注射构建甲状腺癌移植瘤模型,测定移植瘤体积和重量,免疫组化检测Vimentin的表达,Western blot检测TPM3、ERK1/2和p-ERK1/2的表达。结果miR-145-5p在甲状腺癌细胞中低表达,miR-145-5p靶向抑制TPM3表达;miR-145-5p过表达能够明显降低甲状腺癌细胞的侵袭数目和伤口愈合率,并下调p-ERK表达,而TPM3过表达和ERK通路激活剂均可以逆转这些现象;miR-145-5p过表达会使体内移植瘤的重量和体积明显减少,并使移植瘤的Vimentin阳性细胞比率明显减少,TPM3和p-ERK1/2蛋白表达明显下调。结论miR-145-5p靶向TPM3通过ERK信号通路抑制甲状腺癌细胞侵袭和转移。

miR-145-5p inhibits thyroid cancer TPC-1 cell invasion and metastasis via ERK signaling pathway by targeting TPM3

Objective This work aims to study the effect of miR-145-5p on invasion and metastasis of thyroid cancer cells.Methods miR-145-5p mimic plasmid,mimic-NC plasmid,and TPM3 plasmid were separately or jointly transfected into thyroid cancer cells by Lipofectamine2000.Expression of miR-145-5p and TPM3 mRNA was detected by RT-qPCR.The targeted relationship was detected by dual luciferase reporting assay.Cell invasion ability was detected by Transwell method.Cell migration ability was measured by a scratch test.Expression of ERK1/2,and p-ERK1/2 was detected by Western blot.A thyroid cancer xenograft model was constructed by subcutaneous injection of the right hind limb of nude mice.The volume and weight of the transplanted tumor were determined.Expression of vimentin was detected by immunohistochemistry.Expression of TPM3,ERK1/2 and p-ERK1/2 was detected by Western blot.Results Expression of miR-145-5p is decreased in thyroid cancer cells,and miR-145-5p was found to target and inhibit TPM3 expression.Overexpression of miR-145-5p significantly reduced the number of invasion and wound healing of thyroid cancer cells,and down-regulated p-ERK expression,whereas both TPM3 overexpression and ERK pathway activators reversed the miR-145-5p-induced effects(P<0.01).Overexpression of miR-145-5p significantly reduced the weight and volume of transplanted tumors in vivo,and significantly reduced the ratio of Vimentin-positive cells in transplanted tumors and down-regulated TPM3 and p-ERK1/2 protein expression(P<0.01).Conclusion miR-145-5p inhibits thyroid cancer cell invasion and metastasis via ERK signaling pathway by targeting TPM3.