Since CATS interacts with the CALM/AF10 fusion protein which is present in the U937 cells, we sought to investigated whether CATS depletion in U937 cells would affect the expression of the CALM/AF10-leukemia deregulated genes HOXA5, HOXA7, HOXA9, HOXA10, HOXA11 and MEIS1. Expression of HOXA7, HOXA9, HOXA10, HOXA11, and MEIS1 genes were unaffected in U937 upon CATS depletion. The gene discussed is MEIS1; the disease is leukemia.