VCAM1 and cancer: Interestingly, PAK4KO reduced the ICAM-1 expression in pancreatic cancer cells, while the VCAM-1 expression was unaffected compared to the WT (Figure 2c), showing that the upregulated ICAM-1 and VCAM-1 in the gemcitabine-treated PAK4KO tumours were expressed in stroma cells rather than cancer cells.