LncRNA-TCONS_00034812 is upregulated in atherosclerosis and upregulates miR-21 through methylation in vascular smooth muscle cells.

LncRNA-TCONS_00034812 is a critical player in the proliferation of aortic smooth muscle cells. It is known that artery injury plays an important role in atherosclerosis. However, the potential implication of LncRNA-TCONS_00034812 in atherosclerosis remains unclear. In this study, we collected artery specimens from patients with atherosclerosis and healthy controls to investigate the involvement of LncRNA-TCONS_00034812 in atherosclerosis. Sixty patients with atherosclerosis and 60 controls, admitted at The First Hospital of Changsha (Changsha, China), between March 2017 and March 2019, were included. An artery biopsy was performed on all participants to obtain the artery specimens. Real-time quantitative PCR were performed to quantify the relative expression level of LncRNA-TCONS_00034812. Its role in atherosclerotic lesion was evaluated in (high fat diet) HFD-induced ApoE-/- mice. Moreover, human aortic smooth muscle cells (HAOSMCs) was employed to study functional role of LncRNA-TCONS_00034812 overexpression and knockdown by methylation-specific PCR and cell proliferation assay. Overexpression of TCONS_00034812 resulted in miR-21 upregulation and a decrease of miR-21 gene methylation. In contrast, silencing of TCONS_00034812 caused miR-21 downregulation and an increase of miR-21 gene methylation. Cell proliferation analysis indicated that the overexpression of TCONS_00034812 and miR-21 promoted cell proliferation, while silencing of TCONS_00034812 played an opposite role. Moreover, miR-21 overexpression weakened the effects of silencing TCONS_00034812 on cell proliferation. In summary, LncRNA-TCONS_00034812 is upregulated in atherosclerotic samples, and its overexpression upregulates miR-21 through methylation in human aortic smooth muscle cells (HAOSMCs). Our study indicates that LncRNA-TCONS_00034812 could serve as a potential biomarker for diagnosis of atherosclerosis.