VCAM1 and cancer: PAK4KO enhanced the expression of ICAM-1 and VCAM-1 in tumour tissues (Figure 5A,B) by 3 and 4 times, respectively, but not by the pancreatic cancer cells (Figure 4C), indicating that PAK4KO specifically stimulated the expression of ICAM-1 and VCAM-1by the non-cancer stromal cells.