Ikaros-regulated genes in a mouse model of BCR-ABL1+ acute lymphoblastic leukemia

To examine Ikaros tumor suppressor mechanisms, we have utilized inducible RNAi to dynamically restore endogenous Ikaros expression in BCR-ABL1+ B-ALL driven by its knockdown (Ikaros knockdown), and compared these tumors to tumors driven by BCR-ABL1 alone (control). Restoration of Ikaros causes rapid regression of tumor cells in vivo, significantly prolonging tumor transplant recipient survival. Using both transgenic and retroviral approaches, we conducted expression analysis of B-ALL by RNA-Seq and have identified a series of Ikaros-regulated genes within established tumor cell in vivo. Comparison of Ikaros-activated and Ikaros-repressed genes with human B-ALL expression data shows a set of conserved Ikaros target genes, some of which are associated with patient outcome (namely, CTNND1, IFITM3 and EMP1). Overall design: RNA-seq was performed on BCR-ABL1+ B-ALL with inducible Ikaros knockdown (Ikaros knockdown, n=8; transgenic n=5, retroviral n=3) or BCR-ABL1+ alone B-ALL (control, n=4; transgenic n=3, retroviral n=1) cells isolated from untreated and three 3-day Dox-treated mice. Samples were run on HiSeq or NextSeq platform. B-ALL B031 was run in technical duplicate. Extended Dox samples (B027: d7 and d10) and relapse samples for B027, B029 and B035 have also been analyzed in this dataset.

82

Witkowski MT, Hu Y, Roberts KG, Boer JM, McKenzie MD, Liu GJ, Le Grice OD, Tremblay CS, Ghisi M, Willson TA, Horstmann MA, Aifantis I, Cimmino L, Frietze S, den Boer ML, Mullighan CG, Smyth GK, Dickins RA