Dysregulation of CBS7/9 boundary inhibits leukemic cell proliferation and prolongs survival time of transplanted NSG mice. (A) Proliferation curves of WT control and CBS7/9^+/− MOLM13 cells were assessed using a cell viability count. (B) FACS analysis of the cell cycle was carried out using propidium iodide staining of WT control or CBS7/9^+/− MOLM13 cells. (C) Survival of sublethally irradiated NSG mice (n = 6 per group) transplanted with WT control or CBS7/9^+/− MOLM13 cells by tail vein injection. (D) FACS analysis of human CD45⁺ cell chimerism in BM, spleen, and PB from representative mice receiving control or CBS7/9^+/− MOLM13 cells. (E) Percentages of human CD45⁺ cells in BM, spleen, and PB of NSG mice 16 days after transplantation of WT (n = 5) or CBS7/9^+/− (n = 4) MOLM13 cells. (F) Anti-hCD45 immunohistochemical staining (IHS; brown) of femur and spleen sections from representative mice transplanted with WT or CBS7/9^+/− MOLM13 cells for 16 days. Original magnification ×200. Data are mean ± SD from 3 or 4 independent experiments. *P < .05, **P < .01, Student t test.