微小RNA-127-3p对乳头状甲状腺癌细胞增殖、侵袭及迁移的影响

Effects of microRNA-127-3p on proliferation,invasion and migration of papillary thyroid cancer cells

目的 探讨微小RNA-127-3p(miR-127-3p)对乳头状甲状腺癌细胞增殖、侵袭及迁移的影响,并明确miR-127-3p与肿瘤细胞侵袭抑制因子(SCAI)基因的靶向关系。方法 选取乳头状甲状腺癌细胞株TPC1、正常人甲状腺细胞株Nthy-ori 3-1为研究对象。将生长良好的TPC1细胞株根据转染方式的不同分为空白组(NC组,未进行任何处理)、miR-NC组(转染miR-127-3p过表达的空载体)、miR-127-3p组(转染miR-127-3p-mimics)、si-NC组(转染SCAI敲低空载体)和si-SCAI组(转染si-SCAI)。采用噻唑蓝(MTT)实验检测细胞增殖能力,Transwell小室实验检测细胞迁移、侵袭能力,实时荧光定量聚合酶链反应(PCR)检测细胞中miR-127-3p、SCAI mRNA的表达水平,蛋白质印迹法(Western blot)检测细胞SCAI蛋白表达水平。采用生物信息预测miR-127-3p与SCAI的靶向作用关系,并使用荧光素酶报告实验进行验证。结果 TPC1细胞中的miR-127-3p表达水平低于Nthy-ori 3-1细胞,SCAI蛋白、SCAI mRNA表达水平高于Nthy-ori 3-1细胞,差异有统计学意义(P<0.01)。与NC组、miR-NC组比较,miR-127-3p组细胞48、72 h时的增殖能力、细胞迁移和侵袭能力降低,差异有统计学意义(P<0.01)。与NC组、si-NC组比较,si-SCAI组细胞48、72 h时的增殖能力、细胞迁移和侵袭能力升高,差异有统计学意义(P<0.01)。与NC组和miR-NC组比较,miR-127-3p组SCAI蛋白表达水平升高,差异有统计学意义(P<0.01)。转载WT-SCAI的miR-127-3p组细胞荧光素酶活性高于转载WT-SCAI的NC组细胞,差异有统计学意义(P<0.05)。结论 乳头状甲状腺癌细胞中的miR-127-3p、SCAI呈低表达,过表达miR-127-3p可能通过促进SCAI的表达抑制乳头状甲状腺癌细胞的增殖、侵袭和迁移。

Objective To investigate the effects of microRNA-127-3p(miR-127-3p)on prolifera-tion,invasion and migration of papillary thyroid cancer cells,and to clarify the targeting relationship between miR-127-3p and tumor cell invasion inhibitor(SCAI)gene.Methods Papillary thyroid car-cinoma cell line TPC1 and normal human thyroid cell line Nthy-ori 3-1 were selected as study objects.The well-grown TPC1 cell lines were divided into blank group(NC group,without treatment),miR-NC group(transfected with miR-127-3p overexpressed empty vector),miR-127-3p group(transfected miR-127-3p-mimics),si-NC group(transfected with empty vector of knockdown SCAI)and si-SCAI group(transfected si-SCAI)according to different transfection modes.The cell proliferation was de-tected by Methyl Thiazolyl Tetrazolium(MTT);cell migration and invasion was detected by transwell assay;the levels of miR-127-3p and SCAI mRNA were detected by real-time fluorescence quantitative polymerase chain reaction(PCR);the expression of SCAI protein was detected by Western blot.The re-lationship between miR-127-3p and SCAI was predicted by bioinformatics,and luciferase assay was used to verify its reliability.Results The level of miR-127-3p in TPC1 cells was lower than that in Nthy-ori 3-1 cells,and the levels of SCAI protein and SCAI mRNA were higher than those in Nthy-ori 3-1 cells(P<0.01).Compared with NC group and miR-NC group,the abilities of proliferation,cell migration and invasion of the miR-127-3p group were decreased at 48 and 72 h(P<0.01).Compared with NC group and Si-NC group,the proliferation ability,cell migration and invasion ability of the si-SCAI group increased at 48 and 72 h,and the differences were statistically significant(P<0.01).Compared with NC and miR-NC groups,the level of SCAI protein in the miR-127-3p group was higher(P<0.01).The luciferase activity of cells transfected with WT-SCAI in the miR-127-3p group was higher than that of cells transfected with WT-SCAI in the NC group(P<0.05).Conclu-sion The expression of miR-127-3p and SCAI is low in papillary thyroid carcinoma cells.The miR-127-3p overexpression may inhibit the proliferation,invasion and migration of papillary thyroid carcinoma cells by promoting SCAI expression.