HOXA9 and leukemia: 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.