MicroRNA-10b Induces Vascular Muscle Cell Proliferation Through Akt Pathway by Targeting TIP30

Abnormal proliferation of vascular smooth muscle cells (VSMCs) contributes significantly to the pathogenesis of atherosclerosis. MiR-10b has recently emerged as a critical mediator in regulating cell proliferation in many diseases. In our study, miR-10b expression was up-regulated in VSMCs isolated from atherosclerotic plaques, as well as in PDGF-stimulated VSMCs. Overexpression of miR-10b promoted cell proliferation of VSMCs. Furthermore, we identified the Tat-interacting protein 30 (TIP30) as a direct target gene of miR-10b. TIP30 was down-regulated in VSMCs isolated from atherosclerosis plaques, as well as in proliferative VSMCs. Knockdown of TIP30 promoted VSMCs proliferation. In addition, miR-10b induced TIP30 down-regulation was accompanied by increased Akt phosphorylation. Akt was critical for miR-10b-mediated VSMCs proliferation. Our results demonstrated that miR-10b contributed to abnormal VSMCs proliferation through inhibiting the Akt pathway by targeting TIP30 in atherosclerosis. The modulation of miR-10b in VSMCs provides a potential target for the therapy of atherosclerosis.