GPR84 upregulates a small set of genes essential for establishment of MLL leukemia while activating β-catenin transcriptional cofactors. (A) The heat map displaying the probe sets/genes differentially expressed in GPR84- and EV-expressing KLSA9M pre-LSCs. The ComparativeMarkerSelection module from GenePattern was used to analyze 3 biological replicates from each cell type using a fold change of ≥3 and P < .03 as the cutoff criteria. The top 20 genes up- and downregulated by GPR84 overexpression are listed on the right. (B) Confirmation of microarray results by real time RT-PCR (N = 4) in KLSA9M pre-LSCs expressing GPR84 cDNA or EV. **P < .01, ***P < .0005, ****P < .0001. Western blot analysis of Meis1a expression in GPR84 KD#1 KLSMLL pre-LSCs (C) or LSCs (D), and in GPR84-overexpressing KLSA9M pre-LSCs (E); western blot analysis of Ms4a3 expression in EV or GPR84-overexpressing KLSA9M pre-LSCs (F); western blot analysis of Tcf7l2 and c-Fos expression in EV or GPR84-overexpressing KLSA9M pre-LSCs (G).