Prostate apoptosis response-4 (Par-4) is a leucine zipper protein linked to apoptotic cell death in prostate cancer and neuronal tissues. The leucine zipper domain of Par-4 (Leu.zip) mediates protein-protein interactions that are essential for sensitization of cells to apoptosis, and overexpression of Leu.zip blocks Par-4 activity in a dominant negative fashion. Ischemia-reperfusion-induced ren...

The G-protein-linked receptor, proteinase-activated receptor-4 (PAR(4)) is activated by proteinases released into the joint during inflammation. It is unclear whether PAR(4) has a pro- or anti-nociceptive effect and whether it directly affects nerve activity. In this study, we examined the expression of PAR(4) in joints and dorsal root ganglion (DRG) neurons and whether activation of PAR(4) has...

Experimental evidence indicates that prostate apoptosis response-4 (Par-4, also known as PAWR) is a key regulator of cancer cell survival and may be a target for cancer-selective targeted therapeutics. Par-4 was first identified in prostate cancer cells undergoing apoptosis. Both intracellular and extracellular Par-4 have been implicated in apoptosis. Relatively little is known about the role o...

Previous studies have shown that protease-activated receptors (PARs) play an important role in various physiological processes. In the present investigation, we determined the expression of PARs on human lung fibroblasts (HLF-1) and whether they were involved in cellular differentiation and pro-inflammatory cytokine and prostaglandin (PGE2) secretion. PAR-1, PAR-2, PAR-3, and PAR-4 were detecte...

BACKGROUND AND AIMS Protease activated receptors (PARs) have been postulated to play a role during intestinal inflammation. The presence and role played by PAR(4) in gastrointestinal functions have not been fully clarified. The aims of this study were: (i) to examine expression of PAR(4) in rat proximal colon; (ii) to determine the mechanical effects induced by PAR(4) activation in longitudinal...

BACKGROUND The serine/threonine kinase LKB1 regulates cell growth and polarity in metazoans, and loss of LKB1 function is implicated in the development of some epithelial cancers. Despite its fundamental role, the mechanism by which LKB1 regulates polarity establishment and/or maintenance is unclear. In the present study, we use the nematode C. elegans to investigate the role of the LKB1 orthol...