Kit tyrosine-protein kinase receptor (KIT)

Kit tyrosine-protein kinase receptor (commonly known as c-KIT or CD117) is a transmembrane receptor tyrosine kinase of the class III family, structurally composed of five extracellular immunoglobulin-like domains, a transmembrane segment, a juxtamembrane regulatory region, and an intracellular split tyrosine kinase domain. Its physiological ligand is stem cell factor (SCF, KITLG), and signaling through KIT is essential for hematopoietic progenitor cell survival, proliferation, gametogenesis, melanocyte development, and gastrointestinal pacemaker cell function. KIT is a critical marker for hematopoietic and other somatic stem cells, and gain-of-function mutations drive various cancers, notably gastrointestinal stromal tumors and acute myelogenous leukemia, where KIT inhibitors form a central therapy. KIT is broadly implicated in stem cell biology, immune cell regulation, and multiple disease processes tied to deregulated cell proliferation and survival.

Other names

CD117c-KITStem cell factor receptorSCFRTyrosine-protein kinase KITProto-oncogene c-Kit

Small molecule tyrosine kinase inhibitors that compete with ATP for binding to the intracellular kinase domain, thereby blocking downstream signaling and oncogenic cell proliferation