VCAM1 and lung cancer: Moreover, siRNA-mediated VCAM-1 knockdown and competitive inhibition experiment using recombinant VCAM-1-D6 protein demonstrated that VCAM-1 is required for lung cancer cell migration into Matrigel and that the VCAM-1-D6 domain of VCAM-1 is a key domain for regulating lung cancer cell migration into Matrigel.