ICAM1 and neoplasm: PAK1KO or PAK4KO suppressed tumour growth by reducing angiogenesis while enhancing vascular normalisation, enhanced the infiltration/activation of T-cells and dendritic cells associated with upregulation of ICAM-1 and VCAM-1 in the tumour microenvironment, and stimulated vascular immune crosstalk via an ICAM-1-mediated mechanism.