To test whether the mechanism-of-action of Venetoclax in CREBBP-mutated B-ALL was through on-target BCL2 inhibition, we employed a doxycycline-inducible shRNA knock-down system, where shRNA expression was directly linked to a fluorescent reporter (Supplementary Fig. 2a–d)26. Here, CREBBP is linked to acute lymphoblastic leukemia.