HGF and acute myeloid leukemia: AML is associated with a growth of the vascularization in the bone marrow but also with a growth of the level of angiogenic factors such as VEGF, the fibroblastic growth factor, the derived growth factor of the platelets, the epidermal growth factor, TNF-alpha and beta, the hepatocyte growth factor (HGF), the angiogenic, angiopoietin-1 in the case of hematologic malignancies, most of these angiogenic factors seem to be secreted by hematopoietic neoplastic cells, assuring the growth and proliferation of the leukemic cells in an autocrine manner.