CLOCK and leukemia: To further explore the functional role of the circadian clock machinery with reference to the leukemia-initiating cell (LIC) propensity of established human T-ALLs, we selected two patient-derived xenografts (PDX) with high transcriptional and protein levels of BMAL1 and CLOCK transcription factors (Fig. S7) and introduced the shCLOCK constructs followed by GFP fluorescent marker through lentiviral transduction.