CK2 impairs Ikaros-mediated transcriptional regulation of genes that control cell cycle progression and the PI3K pathway. (A) CK2 kinase activity assay of the Nalm6 B-ALL cell line and primary B-ALL, normal BM and normal B cell precursors. Graphed are means ± standard error of the mean, comparison by Student t test. CK2 activity was similar in B-ALL with or without IKZF1 mutation or deletion (data not shown). (B-C) Effect of molecular inhibition of CK2 by shRNA (gray) or pharmacologic inhibition of CK2 with CX-4945 (black) on expression of Ikaros target genes that regulate (B) cell cycle progression and (C) the PI3K pathway as measured by qRT-PCR. (D) Effect of CX-4945 treatment on Ikaros-mediated transcriptional repression of promoters of cell cycle and PI3K pathway genes as measured by qRT-PCR. (E-F) Effect of Ikaros knockdown on changes in (E) cell cycle and (F) PI3K pathway gene expression induced by CK2 inhibition with CX-4945 as measured by qRT-PCR.