circADAM22靶向miR-145表达对甲状腺癌细胞增殖和侵袭影响机制的研究

Mechanism of the effect of circADAM22 targeting mir-145 expression on proliferation and invasion of thyroid cancer cells

目的探讨circADAM22靶向miR-145表达在甲状腺癌细胞中的调控作用,并初步分析其影响细胞增殖及侵袭的可能分子机制。方法选取2017-01-01-2018-01-01山东省肿瘤医院50例甲状腺癌组织及相应的癌旁正常组织(距癌组织>5cm)为研究对象。采用荧光实时定量PCR检测人甲状腺癌细胞株中circADAM22表达;采用生物信息学方法预测circADAM22和miR-145靶基因;分别将circADAM22以及相应对照miRNA转染甲状腺癌细胞,通过MTT实验检测细胞增殖能力、Transwell侵袭实验检测细胞侵袭能力及同步抑制miR-145后的逆转水平。结果甲状腺癌组织中circADAM22mRNA表达水平明显较癌旁正常组织高(1.28±0.18 vs 2.78±0.12,t=15.36,P=0.015);抑制circADAM22表达水平后,甲状腺癌细胞的增殖及侵袭能力相应下调,双荧光素酶实验证实circADAM22能与miR-1453′-UTR特异性结合,且可调控miR-145表达活性;而抑制miR-145表达可以在一定程度上逆转circADAM22对甲状腺癌细胞侵袭行为的影响。结论circ ADAM22可靶向下调miR-145表达,抑制甲状腺癌细胞的增殖及侵袭能力。

OBJECTIVE In this study,the regulatory role of circADAM22 targeting Mir-145 expression in thyroid cancer cells was investigated,and the possible molecular mechanisms affecting cell proliferation and invasion were preliminarily analyzed.METHODS From January 1,2017 to January 1,2018,50 cases of thyroid carcinoma and their adjacent normal tissues(5 cm away from the carcinoma tissues)were selected from the breast surgery Department of Shandong Cancer Hospital.Fluorescence real-time quantitative PCR was used to detect the expression of circADAM22 in human thyroid cancer cell lines.The target genes of circADAM22 and mir-145 were predicted by bioinformatics methods.circADAM22 and corresponding control miRNA were transfected into thyroid cancer cells,respectively,and cell proliferation ability was detected by MTT assay,cell invasion ability was detected by transwell assay,and the reversal level after synchronous inhibition of Mir-145 was detected.RESULTS The expression level of circADAM22 mRNA in thyroid carcinoma tissues was significantly higher(1.28±0.18 vs 2.78±0.12,t=15.36,P=0.015).After inhibiting the expression of circADAM22,proliferation and invasion of thyroid cancer cells were down-regulated.Dual-luciferase assay confirmed that circADAM22 specifically binds to Mir-1453′-UTR and can regulate the expression activity of mir-145.Inhibition of mir-145 expression can reverse the effect of circADAM22 on the invasion behavior of thyroid cancer cells to some extent.CONCLUSION circADAM22 can down-regulate the expression of miR-145 and inhibit the proliferation and invasion of thyroid cancer cells.