In contrast, there is strong evidence for the CD25 expression and secretion in many malignant disorders and autoimmune diseases such as human-T cell lymphotropic virus-1(HTLV-1), B cell chronic lymphoblastic leukemia (CLL), acute lymphoblastic leukemia (ALL), hairy cell leukemia (HCL), Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), lung adenocarcinoma, head and neck cancers, as well as multiple sclerosis (MS), rheumatoid arthritis, and systemic lupus erythematosus. Here, IL2RA is linked to hairy cell leukemia.