CCL5 increases lung cancer migration via PI3K, Akt and NF-kappaB pathways.

CCL5 (previously called RANTES) is in the CC-chemokine family and plays a crucial role in the migration and metastasis of human cancer cells. Besides, integrins are the major adhesive molecules in mammalian cells. Here we found CCL5 increased the migration and cell surface expression of alphavbeta3 integrin in human lung cancer cells (A549 cells). CCL5 stimulation increased phosphorylation of the p85alpha subunit of phosphatidylinositol 3-kinase (PI3K) and serine 473 of Akt. Also, we found that PI3K inhibitor (Ly294002) or Akt inhibitor suppressed CCL5-induced migration activities and integrin expression of A549 cells. Transfection of cells with p85 or Akt mutant also reduced CCL5-mediated cancer migration. In addition, treatment of A549 cells with CCL5 induced IkappaB kinase alpha/beta (IKK alpha/beta) phosphorylation, IkappaB phosphorylation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity. Furthermore, the CCL5-mediated increases in p65 Ser(536) phosphorylation were inhibited by Ly294002 and Akt inhibitor. Taken together, our results suggest that CCL5 acts through PI3K/Akt, which in turn activates IKKalpha/beta and NF-kappaB, resulting in the activation of alphavbeta3 integrin and contributing to the migration of human lung cancer cells.