Objective To investigate the expression of lncRNA SENCR in aortic dissection(AD)tissues of AD patients and its effect on and mechanism in the proliferation apoptosis of human vascular smooth muscle cells(HVSMCs).Methods HE staining was done to detect the pathological changes of AD tissues.Fluorescence in situ hybridization(FISH)and RT-qPCR were used to determine the expression of SENCR in the AD tissue and HVSMCs and the expression of SENCR and miR-206 in the tissues,respectively.HVSMCs were cultured and trans-fected with pcDNA3.1-SENCR overexpression plasmids,or pcDNA3.1 blank plasmid.Then cell proliferation and apoptosis were detected by CCK-8 method and Annexin V/PI double staining flow cytometry assay,respectively.Double luciferase report verified the targeting relationship between SENCR and miR-206.Results SENCR was mainly located in the cytoplasm and nucleus of HVSMCs.Compared with the normal tissue,the expression of SENCR in the AD tissues was down-regulated(P＜0.01),but the expression of miR-206 was up-regulated(P＜0.01).Overexpressed SENCR decreased the cell proliferation of HVSMCs(P＜0.01),but significantly increased the cell apoptosis of HVSMCs(P＜0.01).SENCR could target and negatively regulate miR-206.Conclusion The expression of SENCR is down-regulated in AD tissues,and overexpressed SENCR may inhibit the proliferation and promote the apoptosis of HVSMCs by targeting down-regulated miR-206.