Recently, direct cross-comparison among various inhibitors, including DOT1L, bromodomain and extraterminal domain (BET), dihydroorotate dehydrogenase (DHODH), P-TEFb, and menin-MLL1 inhibitors, has shown that they have functional diversity in blocking differentiation, and EPZ-5676 acts specifically on MLL-fused leukemia cell lines and significantly blocks differentiation [22]. This evidence concerns the gene DHODH and leukemia.