Long non-coding RNA SNHG16 regulates human aortic smooth muscle cell proliferation and migration via sponging miR-205 and modulating Smad2.

The present study investigated the role of long non-coding RNA (lncRNA) small nucleolar RNA host gene 16 (SNHG16) in the human aortic smooth muscle cell (HASMC) proliferation and migration and explored the potential link between SNHG16 and atherosclerosis. Our results showed that platelet-derived growth factor (PDGF)-bb treatment promoted cell proliferation and migration with concurrent up-regulation of SNHG16 in HASMCs. Small nucleolar RNA host gene 16 overexpression promoted HASMC proliferation and migration, while SNHG16 knockdown suppressed cell proliferation and migration in PDGF-bb-stimulated HASMCs. The bioinformatic analyses showed that SNHG16 possessed the complementary binding sequence with miR-205, where the interaction was confirmed by luciferase reporter assay and RNA pull-down assay in HASMCs, and SNHG16 inversely regulated miR-205 expression. MiR-205 overexpression attenuated the enhanced effects of PDGF-bb treatment on HASMC proliferation and migration. Moreover, Smad2 was targeted and inversely regulated by miR-205, while being positively regulated by SNHG16 in HASMCs. Smad2 knockdown attenuated PDGF-bb-mediated actions on HASMC proliferation and migration. Both miR-205 overexpression and Smad2 knockdown partially reversed the effects of SNHG16 overexpression on HASMC proliferation and migration. Moreover, SNHG16 and Smad2 mRNA were up-regulated, while miR-205 was down-regulated in the plasma from patients with atherosclerosis. Small nucleolar RNA host gene 16 expression was inversely correlated with miR-205 expression and positively correlated with Smad2 expression in the plasma from atherosclerotic patients. In conclusion, our data showed the up-regulation of SNHG16 in pathogenic-stimulated HASMCs and clinical samples from atherosclerotic patients. Small nucleolar RNA host gene 16 regulated HASMC proliferation and migration possibly via regulating Smad2 expression by acting as a competing endogenous RNA for miR-205.