PathScan^® Inflammation 4-Plex Array Kit #7138

Cells must respond in an appropriate fashion to many complex signaling events. Extracellular signaling cues are organized into well defined signal transduction modules that control fundamental cellular behvior. Three prominent signaling modules that are among the best characterized are the p44/42 MAP kinase (ERK MAPK), p38 Map kinase and the JAK-Stat signal transduction pathways. p44/42 MAPK is activated by a wide variety of extracellular signals including growth and neurotrophic factors, cytokines, hormones and neurotransmitters. p44/42 activation occurs through phosphorylation of threonine and tyrosine at the sequence T*EY* by a dual specificity kinase called MAP kinase kinase (MEK). p38 MAPK is dually phosphorylated in response to pro-inflammatory cytokines or cellular stress. Stat3 (Signal Transducers and Activators of Transcription) is phosphorylated at Tyr705 in response to a variety of cytokines and growth factors. Upon phosphorylation, Stat3 translocates to the nucleus where it acts as a transcription factor. Phosphorylation levels of critical molecular switches such as MAPKs therefore serve as a reliable indicator of the activation state of the entire signaling module. The profiling of phosphorylation events using phospho-specific antibodies is now widely used to investigate diagnostic pathology (1,2). While profiling of protein phosphorylation events was shown to predict the progression of a tumor to a more invasive stage (3), it has been observed that the ratio between p44/42 and p38 MAPK may predict whether tumor cells will proliferate or enter a dormant state in vivo (4). PathScan^® Inflammation 4-Plex Array Kit provides the researcher with means to profile numerous chemical compounds and obtain in-cell relative potency (5).