Based on these findings, we investigated metabolic profiles and analyzed oxygen consumption rates (OCR, Agilent XF Mitostress Test) comparing VEN-sensitive to insensitive leukemias with or without prior exposure to VEN at low concentrations (10 and 100 nM, three hours), which did not yet induce mitochondrial apoptosis signaling as shown by unchanged mitochondrial membrane potential and cytochrome c release (Supplementary Fig. 5). Here, CYCS is linked to leukemia.