RAC1 and cancer: Von Karstedt et al. [17] showed that tumour cell-expressed TRAIL and TRAIL-R2 promote cancer progression, invasion, and metastasis by cancer cell-autonomous activation of Rac1 via the membrane-proximal domain (MPD) of TRAIL-R2 independently of fas-associated death domain (FADD), and according to Hartwig et al. [18] TRAIL is the main immune mechanism supporting cancer growth in colorectal and pancreatic cancer lines, which may also apply to other types of cancers.