T-ALL tumors are not maintained by c-MYC in the absence of NOTCH^IC. (A) Spleens from Top-NOTCH/MIT-c-MYC (left panel) and Top-NOTCH/MIT-NOTCH^IC (right panel) tumors treated for the indicated times with Dox. (B) FACS analysis using anti-CD4-PE and anti-CD8-PerCP-Cy5.5 antibodies to detect double-positive tumor cells in the spleen before and after Dox treatment of mice reconstituted with Top-NOTCH/MIT-c-MYC bone marrow (upper and lower left panels, respectively), wild-type (WT) thymus, and wild-type spleen (upper and lower right panels, respectively).