CD117

CD117, also known as KIT or stem cell factor receptor (SCFR), is a protein that in humans is encoded by the KIT gene. CD117 is a type of tyrosine kinase receptor which is important for the survival and proliferation of certain types of cells. The importance of CD117 spans across various biological processes including hematopoiesis, spermatogenesis, and melanogenesis.

Function

CD117 is a receptor for stem cell factor (SCF), also known as "steel factor" or "c-kit ligand". When SCF binds to CD117, it triggers a cascade of biochemical reactions inside the cell that influence cell survival, proliferation, and differentiation. This receptor is particularly crucial in the signaling pathways that regulate the development and function of mast cells, melanocytes, and germ cells.

Clinical Significance

Mutations in the KIT gene can lead to various medical conditions. For example, gain-of-function mutations are associated with gastrointestinal stromal tumors (GISTs), a type of tumor found in the digestive tract. Conversely, loss-of-function mutations can result in conditions such as piebaldism, which is characterized by the absence of pigment in the skin and hair.

CD117 is also a marker used in hematology and oncology to identify certain types of cells, including stem cells and tumor cells. Its expression is a critical factor in the diagnosis and treatment of various cancers.

Pathology

Abnormal activation of CD117, whether by mutation or overexpression, can lead to uncontrolled cell proliferation and is implicated in various types of cancers. Inhibitors of CD117, such as imatinib, are used to treat tumors that are driven by mutations in the KIT gene.

See also

• Tyrosine kinase inhibitor
• Hematopoietic stem cell
• Melanocyte
• Gastrointestinal stromal tumor