ROR1 and mantle cell lymphoma: ROR1 is expressed in B cell malignancies including chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), mantle cell lymphoma (MCL), acute lymphoblastic leukemia (ALL) and recently also diffuse large B cell lymphoma (DLBCL) as well as in solid tumors such as lung, pancreatic, ovarian, and breast cancers [6,7,10,11,18,19,23].