BRD4 and leukemia: The PROTAC molecule QCA570 (C39H33N7O4S, CAS number 2207569-08–0) developed by Qin et al. showed effective degradation of BET proteins BRD2, BRD3, and BRD4 at low picomolar concentrations and showed more potent proliferation inhibitory activity than other BET degraders such as dBET1, ARV-825, ARV-771, and ZBC260 in human leukemia cell lines.