Peptidomimetics MM-101, MM-102, and MM-103 with improved activities were developed, and the compound MM-102 showed selectively restrains cell growth in leukemia cells with MLL1 fusion proteins through decreasing HoxA9 and Meis-1 expression, which was two key genes in MLL1 fusion proteins in leukemogenesis [129]. The gene discussed is KMT2A; the disease is leukemia.