Spleen size of moribund mice reconstituted with Top-NOTCH/MIT-c-MYC bone marrow is significantly reduced after Dox treatment. (A) Area (length × width) of moribund mice reconstituted with Top-NOTCH/MIT-c-MYC bone marrow, untreated with Dox (No Dox) or treated for 96 hours with Dox. *P = .000009 (Student t test). n = 10. (B) Quantification of CD4⁺CD8⁻ and CD4⁺CD8⁺ T cells in spleens of mice with Top-NOTCH/MIT-c-MYC tumors untreated or treated with Dox for 96 hours. *P = .00022 (Student t test). n = 7.