Nucleophosmin (NPM1) is a nucleolar phosphoprotein involved in the pathogenesis of several hematological malignancies, including non-Hodgkin lymphomas where NPM1 is a frequent translocation partner of the anaplastic lymphoma receptor tyrosine kinase (ALK) gene or AMLs where hotspot mutations of NPM1 delocalize the protein to the cytoplasm and block differentiation [118,119]. Here, ALK is linked to non-Hodgkin lymphoma.