The available data on angiogenesis and expression of VEGF and VEGFR in the bone marrow of patients with BCR-ABL1-negative MPN suggest a significant increase of MVD (Figure 2(c)), especially in primary myelofibrosis (PMF), which might inversely correlate with survival [30, 33, 94–97]. This evidence concerns the gene VEGFA and myeloproliferative neoplasm.