Calcium-binding protein 39-like, also known as CAB39L, is similar to MO25 and is found in the serum of nearly half of all patients diagnosed with acute monocytic leukemia. This protein suggests a role for CAB39L in carcinogenesis. Also, LKB1 activity increases upon the binding of a regulatory complex consisting of the STE20-related adaptor-alpha (STRAD alpha) pseudo kinase and the CAB39L. Recombinant human CAB39L protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.