KIT and gastrointestinal stromal tumor: In a spontaneous mouse model of gastrointestinal stromal tumor (GIST) as well as upon analysis of freshly procured human GISTs, TAMs displayed an M1-like phenotype and function at baseline; however, treatment with Imatinib, that acts as a KIT oncoprotein inhibitor, induced TAMs to become M2-like, in both mice and humans.