To investigate whether STK4 caused β‐catenin phosphorylation, and the phosphorylated β‐catenin was then degraded through proteasomal degradation pathway, colon cancer cells expressing GFP‐STK4 or GFP‐empty plasmids were treated with a proteasome inhibitor (MG‐132) for 6 and 12 h following by western blotting to evaluate the expression of phosphorylated β‐catenin. Here, STK4 is linked to malignant colon neoplasm.