The JAK-STAT Pathway and the JAK Inhibitors

Dozens of cytokines that bind Type I and Type II receptors use the Janus Kinases (JAK) and the Signal Transducer and Activator of Transcription (STAT) proteins pathway for intracellular signaling, orchestrating hematopoiesis, inducing inflammation, and controlling the immune response. Currently, oral JAK inhibitors are being used to treat many inflammatory and myeloproliferative diseases and are also under investigation in several clinical trials for skin diseases. Thus, dermatologists should understand how the JAK-STAT pathway works as well as the mechanism of action of the JAK inhibitors which will certainly become an important part of the dermatologist’s treatment armamentarium in the next few years. Keywords: JAK inhibitors; Janus Kinases; JAK-STAT Pathway List of Abbreviations: AD: Atopic Dermatitis ADP: Adenosine diphosphate Dmards: Disease-Modifying Antirheumatic Drugs JAK: Janus kinase(s) Jaki: Janus kinase Inhibitor(s) PIAS: Protein Inhibitor of Activated STAT P-STAT: Phosphorylated STAT STAT: Signal Transducer and Activator of Transcription TYK2: Tyrosine Kinase 2 Wsxws: Tryptophan-Serine-X-Tryptophan-Serine