IFN-α2a is approved for the treatment of hairy cell leukemia and chronic myelogenous leukemia, IFN-α2b for follicular lymphoma, multiple myeloma, AIDS-related Kaposi's sarcoma, melanoma, cervical intraepithelial neoplasms, and hairy cell leukemia, and IL-2 for the treatment of metastatic melanoma and renal cell carcinoma. Here, IL2 is linked to hairy cell leukemia.