MicroRNA (miRNA) plays a key role in the proliferation and invasion of vascular smooth muscle cells (VSMCs). However, the role and underlying mechanism of miRNAs in VSMCs are not fully understood. Therefore, this study was designed to investigate the role and mechanism of microRNA-1246 (miR-1246) in VSMCs. VSMCs were cultured, and the proliferation of VSMCs was stimulated by platelet-derived growth factor (PDGF-BB) or 15% fetal bovine serum (FBS). The quantitative reverse transcription PCR (qRT-PCR) was used to detect the expression levels of miR-1246 and cystic fibrosis transmembrane conductance regulator (CFTR) in VSMCs. The CCK-8 assay and transwell assay were used to detect the proliferation and invasion of VSMCs. Target gene prediction and screening and luciferase reporter assays were used to verify downstream target genes of miR-1246. Western blotting was used to detect the protein expression levels of PCNA, α-SMA, SM-MHC, Collagen-1, and Cyclin D1 in VSMCs. PDGF-BB and FBS treatment induced VSMCs proliferation and the upregulation of miR-1246 expression. Overexpression of miR-1246 promoted VSMCs proliferation, invasion, and differentiation towards synthetic phenotype, while knockdown of miR-1246 had opposite effects. In addition, CFTR was found to be a direct target for miR-1246, and miR-1246 inhibited the expression of CFTR. Moreover, overexpression of CFTR inhibited VSMC proliferation and synthetic differentiation, while overexpression of miR-1246 partly abolished the effects of CFTR overexpression on VSMCs proliferation and differentiation. Our data suggest that MiR-1246 promotes VSMC proliferation, invasion, and differentiation to synthetic phenotype by regulating CFTR. MiR-1246 may be a potential therapeutic target for atherosclerosis.

MicroRNA (miRNA) 在血管平滑肌细胞 (VSMC) 的增殖和侵袭中起关键作用。然而，miRNA 在 VSMC 中的作用和潜在机制尚不完全清楚。因此，本研究旨在探讨 microRNA-1246 (miR-1246) 在 VSMC 中的作用和机制。培养VSMCs，通过血小板源性生长因子(PDGF-BB)或15%胎牛血清(FBS)刺激VSMCs增殖。定量逆转录PCR（qRT-PCR）用于检测VSMCs中miR-1246和囊性纤维化跨膜电导调节剂（CFTR）的表达水平。CCK-8法和transwell法检测VSMCs的增殖和侵袭。使用靶基因预测和筛选以及荧光素酶报告基因检测来验证 miR-1246 的下游靶基因。Western blotting检测VSMCs中PCNA、α-SMA、SM-MHC、Collagen-1和Cyclin D1的蛋白表达水平。PDGF-BB 和 FBS 处理诱导 VSMCs 增殖和 miR-1246 表达的上调。miR-1246 的过表达促进了 VSMCs 的增殖、侵袭和向合成表型的分化，而 miR-1246 的敲低具有相反的作用。此外，发现CFTR是miR-1246的直接靶点，miR-1246抑制CFTR的表达。此外，CFTR 的过表达抑制 VSMC 增殖和合成分化，而 miR-1246 的过表达部分消除了 CFTR 过表达对 VSMC 增殖和分化的影响。我们的数据表明 MiR-1246 通过调节 CFTR 促进 VSMC 增殖、侵袭和分化为合成表型。