CXCL12 and neoplasm: In response, sensitized PMN cells increase surface expression of fibronectin, which increases colonization of myeloid and bone marrow cells via their upregulation of fibronectin-binding integrin-α4β1, and increase secretion of chemokines such as SDF-1(CXCL12), TNF-α, TGF-β, VEGF-A, CXCL12 or PLGF [2, 8] that serve as tumor attractants.