MiR-140-3p is Involved in In-Stent Restenosis by Targeting C-Myb and BCL-2 in Peripheral Artery Disease.

AIM: In-Stent Restenosis (ISR) is the major reason for recurrent ischemia and amputation after endovascular treatment of Peripheral Artery Disease (PAD). Our previous study demonstrated that miR-140-3p is significantly down-regulated in PAD arteries. However, expression and function of miR-140-3p in ISR of human PAD are currently unclear.The aim of this study is to determine the miR-140-3p expression and its regulative role in ISR of PAD.

METHODS: The RNA level was determined by quantitative real-time polymerase chain Reaction (qRT-PCR) and in situ hybridization. Primary cultured ASMCs were isolated from human femoral arterial of the healthy donors or ISR patients. Cell proliferation was determined by Edu incorporation and CCK-8 assay. Apoptosis was determined by Annexin-Ⅴ/PI Double-Staining assay and TUNEL assay. A rat carotid artery balloon angioplasty model was used to investigate the effect of miR-140-3p on restenosis.

RESULTS: MiR-140-3p was significantly down-regulated in PAD and ISR arteries than normal arteries. Primary cultured ISR ASMCs exhibited elevated proliferation and down-regulated miR-140-3p than normal ASMCs. Transfection of miR-140-3p mimic attenuated PDGF-BB-induced proliferation in cultured ASMCs and induced apoptosis. Luciferase reporter assay indicated that miR-140-3p transfection significantly down-regulated C-Myb and BCL-2 in ISR ASMCs by targeting to their 3'-UTRs. MiR-140-3p transfection induced anti-proliferation and apoptosis in ASMCs, which were ameliorated by over-expression of C-Myb or BCL-2. Moreover, the animal study showed that miR-140-3p can reduce restenosis following angioplasty via targeting C-Myb and BCL-2.

CONCLUSIONS: The result suggests that miR-140-3p regulates ASMC function via targeting C-Myb and BCL-2 in the process of ISR in PAD. The novel findings may offer a hopeful therapeutic target for human PAD.