The TCGA data set of human AML samples and miR-155 mutant AML cell lines identify an inverse correlation between miR-155 levels and the IFN response in FLT3-ITD⁺AML. (A) Box plot showing MIR155HG and mature miR-155 expression levels in FLT3-WT and FLT3-ITD AML samples from the TCGA data set. (B-C) GSEA of the TCGA data set identifies the IFN-α response and IFN-γ response as hallmark differences between FLT3-ITD AML and FLT3-WT AML. (D) Expression level of representative IFN-responsive genes from the TCGA data set in FLT3-WT and FLT3-ITD AML. (E) Relative expression of miR-155 in Molm14 and MV4-11 cells infected with EV or 155-CR1 vectors determined by qRT-PCR. Expression normalized to 5S. n = 3 biological replicates for each condition. (F-G) qRT-PCR analysis of representative IFN-responsive genes in Molm14 (F) or MV4-11 (G) cells infected with either EV or 155-CR1 vectors. Expression normalized to L32, with the EV-infected cell average set to a relative expression value of 1. n = 3 biological replicates for each condition. (H) Western blot of STAT1 in MV4-11 cells infected with either EV or 155-CR1 constructs. Replicates represent cells grown in independent wells for 72 hours. ACTIN serves as the loading control. LentiCRISPR data represent at least 2 independent experiments. Data represented as mean ± SEM. *P ≤ .05; **P ≤ .01; ***P ≤ .001; ns, P > .05. FDR, false discovery rate; NES, normalized enrichment score.