Venetoclax and teriflunomide effects on CTP and dCTP levels. (A) BAX is a p53 target gene that is approximately twofold less expressed in TP53-mutated vs WT TP53 AML cells, whereas BCL2 and BAK1 are similarly expressed. TCGA RNA-sequencing gene-level log₂(x+1) transformed RSEM normalized counts, primary AML cells containing WT TP53 (no TP53 mutations or deletions by GISTIC threshold analyses of copy number; n = 129) or containing mutated TP53 and complex (≥3) cytogenetic abnormalities (n = 16). P value from unpaired 2-sided t test. (B) Teriflunomide produced larger decreases in CTP and dCTP in TP53-mutated and WT-TP53 AML cells than venetoclax. Venetoclax 2μM (20nM for MOLM13) or teriflunomide 20μM were added once to THP1, K562, and MOLM13 AML cells (standard clinical doses of venetoclax or teriflunomide produce peak plasma concentrations of up to 2μM and 100μM, respectively). Nucleotide levels measured by LC-MS/MS at 24 hours. Quantifications by reference to assembled standard curves. Independent experiments, triplicate (data for K562 are duplicate because of LC injection error). Means ± SD. P values from paired 1-sided t test, teriflunomide vs vehicle. P values for venetoclax vs vehicle were all >.05. Aggregated data and analyses, including for adenine triphosphate and guanine triphosphate, are shown in supplemental Figure 1. Mut, mutated; Teri, teriflunomide; Ven, venetoclax; UTP, uridine triphosphate.