a Heatmap of differentially expressed lncRNAs. On top of the heatmap, ETV6-RUNX1-negative B-ALL samples are labeled in blue and ETV6-RUNX1-positive B-ALL samples are labeled in red. Clustering was performed based on the Spearman correlation coefficient. Our candidate lncRNA, TCL6, is highlighted in bold. b Volcano plot of the differential expression results. The horizontal dashed line represents a threshold of FDR = 0.05. The vertical dashed line represents the thresholds of fold change = −1.5 and fold change = 1.5. Red dots represent the statistically significant differentially expressed lncRNAs. Our candidate lncRNA, TCL6, is highlighted in bold. c Correlation of the expression of lncRNA/mRNA pairs in pediatric B-ALL datasets. We focused our analysis on the unique lncRNA/mRNA pairs that were differentially expressed in our microarray data. For each pair, the Spearman correlation coefficient between the normalized expression of the lncRNA and the normalized expression of the associated mRNA was assessed in our data, as well as in external datasets of B-ALL patients and cell lines. Larger dots represent lower FDR-adjusted p-values. Our candidate lncRNA/mRNA pair, TCL6/TCL1B, is highlighted in bold. The sample sizes were: n = 46 for our data, n = 80 for Lee et al.8, n = 64 for Ghazavi et al.5 and n = 44 for Fernando et al.6. In addition, we analyzed data from 13 B-ALL cell lines from the Cancer Cell Line Encyclopedia (CCLE). Missing values are represented with an “NA” mark.