PAK2, a serine-threonine kinase, is a member of the p21-activated kinase (PAK) family. It is activated by GTP-bound rho family GTPases, Rac, and Cdc42, and regulates various cellular processes such as actin dynamics, cell adhesion, and motility. PAK2 is involved in multiple signaling pathways, including those related to pancreatic acinar cell function, cancer progression, and myelination [2].

In pancreatic acinar cells, inhibition of PAK2 by specific inhibitors like IPA-3, FRAX597 or using a PAK2-dominant negative-Advirus suppressed the activation of focal-adhesion kinases, mitogen-activated protein-kinases and reversed the dual effect on the PI3K/Akt/GSK-3β pathway. PAK2-inhibition also protected acini from CCK-induced ROS-generation, caspase/trypsin-activation, cell-necrosis and reduced proteolytic-activation of PAK-2p34, suggesting its role in pancreatitis [1]. In pancreatic cancer, single-cell and bulk data analysis identified PAK2 as a key gene promoting liver metastasis. Silencing PAK2 in pancreatic cancer cells decreased their proliferative and invasive capacity [3]. In Schwann cells, deletion of Pak2 in a Schwann cell-specific knockout mouse (scPak2-/-) led to severe hypomyelination, slowed nerve conduction velocity and behavior dysfunctions, indicating PAK2 is necessary for myelination in the peripheral nervous system [4].

In conclusion, PAK2 is crucial in multiple biological processes. Its roles in pancreatitis, cancer metastasis and myelination have been revealed through various functional studies including gene knockout models. Understanding PAK2's functions provides potential therapeutic targets for diseases like pancreatitis and pancreatic cancer, and insights into the mechanisms of myelination in the peripheral nervous system.

References:

1. Nuche-Berenguer, Bernardo, Ramos-Álvarez, Irene, Jensen, R T. 2016. The p21-activated kinase, PAK2, is important in the activation of numerous pancreatic acinar cell signaling cascades and in the onset of early pancreatitis events. In Biochimica et biophysica acta, 1862, 1122-36. doi:10.1016/j.bbadis.2016.02.008. https://pubmed.ncbi.nlm.nih.gov/26912410/

2. Wu, Megan, Sarkar, Chandan, Guo, Bin. 2024. Regulation of Cancer Metastasis by PAK2. In International journal of molecular sciences, 25, . doi:10.3390/ijms252413443. https://pubmed.ncbi.nlm.nih.gov/39769207/

3. Yang, Hao, Li, Zhongyi, Zhu, Shiqi, Xu, Wei, Xu, Chunfang. 2024. Molecular mechanisms of pancreatic cancer liver metastasis: the role of PAK2. In Frontiers in immunology, 15, 1347683. doi:10.3389/fimmu.2024.1347683. https://pubmed.ncbi.nlm.nih.gov/38343537/

4. Hu, Bo, Moiseev, Daniel, Schena, Isabella, Chernoff, Jonathan, Li, Jun. . PAK2 is necessary for myelination in the peripheral nervous system. In Brain : a journal of neurology, 147, 1809-1821. doi:10.1093/brain/awad413. https://pubmed.ncbi.nlm.nih.gov/38079473/