XPO1 and cancer: In addition to overexpression of CRM1 and CRM1 fusing with other proteins found in leukemias, a mutation within CRM1, specifically an E571K mutation has been found in a number of cancers including Chronic Lymphocytic Leukemia, Hodgkins Lymphoma, Primary Mediastinal B-Cell lymphoma, Extra-nodal Natural Killer/T-Cell Lymphoma, and Diffuse Large B-Cell lymphoma [7–10].