VEGFA and leukemia: Several studies have shown that AML cells release angiogenic growth factors such as VEGF within the bone marrow and that subsets of acute leukemias also express VEGF receptors; thus, autocrine stimulation of leukemia cells by VEGF may result in proliferation, migration, and resistance to chemotherapy [53]; VEGF exerts indeed its trophic effect on malignant myeloid progenitors via either paracrine or autocrine interaction [54].