Human Mast/Stem Cell Growth Factor Receptor Kit (KIT) Protein

Background

The KIT protein, also known as the KIT receptor tyrosine kinase or CD117, is a proto-oncogene that encodes a transmembrane receptor. It plays essential roles in cell growth, survival, migration, and differentiation in several types of cells, especially in hematopoietic stem cells, germ cells, melanocytes, and cells in the gastrointestinal tract. The gene encoding KIT is located on chromosome 4q12 and is highly conserved across species, highlighting its fundamental role in development and cellular homeostasis. KIT is activated by binding to its ligand, stem cell factor (SCF), also known as mast cell growth factor. This binding triggers a cascade of downstream signaling pathways critical for normal cellular processes. However, mutations in KIT can result in its constitutive activation, which is implicated in various diseases, including gastrointestinal stromal tumors (GISTs), systemic mastocytosis, acute myeloid leukemia (AML), and other cancers. As a proto-oncogene, KIT’s aberrant signaling due to mutation can drive tumorigenesis, making it a target for cancer therapies, particularly tyrosine kinase inhibitors (TKIs).