Effects of integrin α5β1 on the proliferation and migration of human aortic vascular smooth muscle cells

Integrin (ITG) α5β1 is a dominant fibronectin receptor that is abundantly expressed on the surface of vascular smooth muscle cells (VSMCs). However, the association between integrin α5β1 and the proliferation and migration of VSMCs has yet to be elucidated. The aim of the present study was to characterize the roles of ITGα5 and ITGβ1 in the proliferation and migration of VSMCs, and to determine the effects of ITGα5β1 on integrin-linked kinase (ILK) and focal adhesion kinase (FAK) mRNA expression. Lentiviral expression vectors as well as RNA interference vectors of ITGα5 and ITGβ1 were successfully constructed and transfected into VSMCs to obtain ITGα5- and ITGβ1-overexpressing or -silenced cells, respectively. Cell cycle distribution, proliferation and migration were analyzed in the transfected VSMCs in order to clarify the roles of ITGβ1 and ITGα5 in the proliferation and migration of VSMCs. ITGβ1 was markedly associated with the proliferation and migration of VSMCs, and FAK was shown to be involved in the signaling pathways of ITGβ1. ITGα5 did not exert any effects on VSMCs. The results of the present study may provide a possible therapeutic target for the prevention and treatment of early vascular disease associated with VSMCs.