c-Kit (Mast/stem cell growth factor receptor, SCFR or CD117) is a proteinthat in humans is encoded by the KIT gene. c-Kit (CD117) is an important cell surface marker used to identify certain types of hematopoietic(blood) progenitors in the bone marrow. c-Kit is a cytokine receptor expressed on the surface of hematopoietic stem cells as well as other cell types. Altered forms of this receptor may be associated with some types of cancer. c-Kit is a receptor tyrosine kinase type III, which binds to stem cell factor. When c-Kit binds to stem cell factor (SCF) it forms adimer that activates its intrinsic tyrosine kinase activity, that in turn phosphorylates and activates signal transduction molecules that propagate the signal in the cell. Signalling through c-Kit plays a role in cell survival, proliferation, and differentiation.