ddC displays efficacy in mouse models of human AML. (A-B) OCI-AML2 cells were injected subcutaneously into the flank of SCID mice. Mice were treated with ddC (35 or 75 mg/kg per day by i.p. injection) or vehicle control for 11 days (n = 8 per group). Tumor volume (A) and weight (B) were assessed from excised tumors. Mean ± SD. (C) Relative mtDNA was assessed from xenograft tumors excised from ddC or vehicle-treated mice in panel A by qRT-PCR. Mean ± SD; n = 3 per group. (D) Relative mRNA expression for mt-COX I and mt-COX II was assessed by qRT-PCR in tumors excised from mice treated with 300 mg/kg per day of ddC or vehicle control for 11 days. Mean ± SD; n = 3 per group. (E) Protein levels of mt-COX II, nu-COX IV, and VDAC from whole-cell extracts of tumors from panel A were assessed by immunoblotting. For all experiments, *P < .05, ***P < .001, ****P < .0001 using the Bonferroni posttest after 1-way ANOVA in panels A-C, and the Student t test in panel D.