Aldh3a2 is essential for leukemia cells in vitro and in vivo. (A) Relative Aldh3a2 expression in L-GMPs vs N-GMPs.25 (B) Validation of Aldh3a2 knockdown by 2 independent shRNAs (Aldh3a2-sh-1 and Aldh3a2-sh-2 from the screen) by quantitative polymerase chain reaction. (C) Aldh3a2 knockdown with 2 independent shRNAs significantly decreases the number of L-GMPs in methylcellulose compared with L-GMPs infected with control shRNA. (D) L-GMPs were infected with shRNA Aldh3a2-sh-1, Aldh3a2-sh-2, or control and injected into sublethally irradiated C57BL6/J mice for disease development. Kaplan-Meier survival curve of animals that developed leukemia is shown. (E) Sublethally irradiated C57BL/6J mice were injected with Aldh3a2fl/fl:Mx1-Cre+ (Aldh3a2-mut) and Aldh3a2fl/fl:Mx1-Cre− (Aldh3a2-ctrl) leukemia cells from primary leukemic mice. Forty-eight hours after injection of cells, mice were injected with 3 doses of polyinosinic-polycytidylic acid [Poly(I):Poly(C)] on alternate days, and leukemia development was monitored. Kaplan-Meier survival curve of animals that developed leukemia is shown. Data are representative of ≥2 independent experiments; n = 5 mice per genotype per experiment. Data are represented as mean ± standard deviation. P > .05 was considered nonsignificant. *P < .05, **P < .01, ***P < .001.