A microRNA‑17‑5p/homeobox B13 axis participates in the phenotypic modulation of vascular smooth muscle cells

Abstract

Vascular smooth muscle cells (VSMCs) serve a decisive role in intimal hyperplasia, a common pathophysiological process that leads to numerous vascular disorders. The present study aimed to investigate the unknown mechanisms underlying VSMC phenotypic modulation and identified a novel microRNA (miRNA/miR)-17-5p/homeobox B13 (HOXB13) axis involved in the phenotypic switching, proliferation and migration of VSMCs. VSMCs were isolated from the thoracic aorta of Sprague-Dawley rats, cell proliferation was determined by Cell Counting Kit-8 (CCK-8) assay, cell migration was examined by Transwell migration assay and gene expression was detected using reverse transcription-quantitative PCR and western blot analyses. It was firstly found that incubation with platelet-derived growth factor-BB (PDGF-BB) recombinant protein resulted in a significant increase in HOXB13 expression in VSMCs. Using multiple miRNA prediction tools, miR-17-5p was identified as a potential regulator for HOXB13, since it had a 7-base perfect binding site and a 5-base imperfect binding site with the 3'-untranslated region of HOXB13 mRNA, and these sequences were highly conserved across species. The regulatory effect of miR-17-5p on HOXB13 was validated using luciferase reporter assays. The expression level of miR-17-5p was increased in VSMCs under PDGF-BB stimulation, and was negatively correlated with HOXB13 mRNA and protein expression. Moreover, the miR-17-5p mimics significantly inhibited the proliferation and migration of VSMCs, while antagomiR-17-5p showed the opposite effects, which could be abolished by HOXB13 knockdown. The miR-17-5p/HOXB13 axis also regulated the expression levels of the markers of differentiated VSMCs (α-smooth muscle actin, transgelin and smoothelin), proliferating cell nuclear antigen and cell migration proteins, including MMP-2 and -9. In conclusion, the present study demonstrated that miR-17-5p inhibited the phenotypic modulation VSMCs stimulated by PDGF-BB by downregulating HOXB13, indicating that these factors may be potential therapeutic targets for intimal hyperplasia.

Defining the miRnome of Saphenous Vein Smooth Muscle Cells from Patients with Type 2 Diabetes Mellitus

“…Within the literature, the influence of miR-17 on SMC phenotype is species and contextdependent. It is associated with a contractile phenotype in both murine and rodent SMCs treated with the pro-proliferative platelet-derived growth factor-BB (PDGF-BB; [19,24]) and in human aortic SMCs treated with thrombospondin [20]; however, it can also promote dedifferentiation to a synthetic phenotype in rodent SMCs treated with oxidized LDL [21] and in a human aortic vascular SMCs cell line in response to inflammatory stimuli [23]. Furthermore, miR-17 is upregulated in the plasma of atherosclerosis patients and can promote atherosclerosis in mice [22].…”

Deciphering the emerging landscape of HOX genes in cardiovascular biology, atherosclerosis and beyond (Review)

“…Mechanistically, it maintains a contractile form of VSMCs by activation of PPARγ ( 12 ). In addition, Yu et al ( 67 ) demonstrated that HOXB13 is involved in the phenotypic modulation of VSMCs induced by platelet-derived growth factor-BB in the miR-17-5p-HOXB13 axis. Although the aforementioned findings have shown that the HOX gene is linked to vascular remodeling, key mechanistic insight into governing vascular remodeling remains poor and a gamut of HOX gene investigation, particularly in vivo exploration, is currently lacking, limiting our understanding of its causal role in vascular remodeling; thus, abundant work remains to be done in the future.…”

“…For example, mi-99a-5p alleviates atherosclerosis via regulating HOXA1 ( 30 ). In addition, the miR-17-5p/HOXB13 axis participates in the phenotypic modulation of VSMCs ( 67 ). In short, ncRNAs may regulate the expression of HOX genes and have a potential role in atherosclerosis.…”

“…For example, mi-99a-5p alleviates atherosclerosis via regulating HOXA1 (30). In addition, the miR-17-5p/HOXB13 axis participates in the phenotypic modulation of VSMCs (67).…”