Tracing PAKs from GI inflammation to cancer.

P-21 activated kinases (PAKs) are effectors of Rac1/Cdc42 which coordinate signals from the cell membrane to the nucleus. Activation of PAKs drive important signalling pathways including mitogen activated protein kinase, phospoinositide 3-kinase (PI3K/AKT), NF-κB and Wnt/β-catenin. Intestinal PAK1 expression increases with inflammation and malignant transformation, although the biological relevance of PAKs in the development and progression of GI disease is only incompletely understood. This review highlights the importance of altered PAK activation within GI inflammation, emphasises its effect on oncogenic signalling and discusses PAKs as therapeutic targets of chemoprevention.