Published online Jan 21, 2016. doi: 10.3748/wjg.v22.i3.1224
Peer-review started: May 11, 2015
First decision: August 31, 2015
Revised: September 17, 2015
Accepted: November 19, 2015
Article in press: November 19, 2015
Published online: January 21, 2016
Processing time: 252 Days and 5.2 Hours
P21-activated kinases (PAKs) are central players in various oncogenic signaling pathways. The six PAK family members are classified into group I (PAK1-3) and group II (PAK4-6). Focus is currently shifting from group I PAKs to group II PAKs. Group II PAKs play important roles in many fundamental cellular processes, some of which have particular significance in the development and progression of cancer. Because of their important functions, group II PAKs have become popular potential drug target candidates. However, few group II PAKs inhibitors have been reported, and most do not exhibit satisfactory kinase selectivity and “drug-like” properties. Isoform- and kinase-selective PAK inhibitors remain to be developed. This review describes the biological activities of group II PAKs, the importance of group II PAKs in the development and progression of gastrointestinal cancer, and small-molecule inhibitors of group II PAKs for the treatment of cancer.
Core tip: Group II p21-activated kinases (PAKs) (PAK4, 5 and 6) are pluripotent kinases that regulate many fundamental cellular processes, including cytoskeletal organization, cell cycle regulation, cell survival and cell adhesion, and have therefore been implicated in carcinogenesis and cancer progression. Members of the group II PAKs, particularly PAK4, have emerged as attractive targets for the development of anticancer drugs. In this review, we summarize the latest findings on the biological activities of group II PAKs, the important roles of group II PAKs in gastrointestinal cancer and the current status of the development of small-molecule inhibitors of PAK4 for the treatment of cancer.