Dok-2 also known as p56DOK is constitutively tyrosine phosphorylated in hematopoietic progenitors isolated from chronic myelogenous leukemia (CML) patients in the chronic phase. Dok-2 a critical substrate for p210(bcr/abl), a chimeric protein whose presence is associated with CML. Dok-2 plays a crucial role in cellular signaling pathways, particularly in hematopoietic cells, where Dok-2 acts as a negative regulator of growth factor signaling. Dok-2 is primarily located in the cytoplasm, where Dok-2 interacts with various signaling molecules, including the Bcr-Abl fusion protein, which is implicated in chronic myelogenous leukemia. The ability of Dok-2 to modulate signaling pathways is vital for maintaining cellular homeostasis and preventing uncontrolled cell proliferation.