miRNA expression in pediatric T-ALL. (A) Twenty most abundantly expressed miRNAs in different cytogenetic subgroups of 41 T-ALL clinical specimens as assessed by TLDA and normalized to the RNU48 expression in a given sample (2^−∆Ct). miRNAs are ranked by expression levels (given as percentage of RNU48 expression). (B) Heatmap of miRNAs differentially expressed in 3 cytogenetic subgroups of T-ALL. Normalized expressions (ΔCt z-values) were color-coded by a gradient from green (underexpressed) to red (overexpressed) relative to the mean (ANOVA adjusted P values: .005 [miR-135a], .005 [miR-125b], .013 [miR-100], .03 [miR-506], .03 [miR-99a], .04 [miR-153]). (C-E) Comparison of miR-125b, miR-99a, and miR-100 levels in TLX3 vs non-TLX3 T-ALL samples by R-Q-PCR (Exiqon). miRNA expression is normalized to RNU44; levels in DP T cells are used as calibrator (2^−∆∆Ct): (C) miR-125b (n = 25 vs n = 33), (D) miR-99a (n = 16 vs n = 16), and (E) miR-100 (n = 16 vs n = 16). ***P < .001, Mann-Whitney U test. Ct, cycle threshold; NS, not significant.