CD34 and chronic myelogenous leukemia, BCR-ABL1 positive: Not surprisingly, pharmacological inhibition of p53 degradation with a small molecule reactivating p53 and inducing tumor apoptosis (RITA) combined with a BET inhibitor to block c-MYC transcription was shown to synergistically increase apoptosis in CML CD34+ cells with a lesser effect on normal HSCs, at least at low concentrations57.