KAT5 and neoplasm: Later study showed that RUVBL1 may not be necessary for the histone H3/4 acetylation in the regulation of KAI1, a tumor suppressor gene, since knockdown of RUVBL1 showed limited effect on histone H3/4 acetylation, but TIP60 is indispensable while knockdown of TIP60 significantly inhibited H3/4 acetylation [41].