ABT-737 treatment-induced apoptosis of AML cells in the liver and the spleen of the mice, despite persistence of BCL-2 in the RAS-GTP complex and relocalization of the RAS:BCL-2 complex. (A) Histogram of mean ± standard deviation (SD) showing an increase of late/necrotic apoptotic cells (n = 3). (B) Paired untreated and treated radioisotope heat maps of ^99mTc labeled annexin-V, which targets apoptotic cells and is metabolized in the kidney and bladder, shows greater intensity around the location of the liver in the pretreated AML mouse (day 0, n = 6), which is increased after day 23 (postday 23) after 10 injections. Histogram of mean ± SD showing an increase of apoptotic cells in AML mice after treatment (n = 5 mice), whereas WT mice do not show a significant increase in uptake of the label (WT, n = 14 untreated and n = 3 treated). (C) Representative DNA fragmentation as demonstrated by TUNEL-positive myeloid cells is significantly greater (postday 33) in the liver of mice; histogram of untreated and treated AML mice (mean ± SD of n = 4). (D) Representative western blot of spleen cells of AML mice probed with anti-caspase 3 antibody showing untreated (day 0) and caspase 3-mediated cleavage after treatment (postday 33) with reprobing with anti-βactin antibody showing protein loading. Results are representative of 3 mice. (E) Representative western blot of protein lysates from Mac-1⁺ and Sca-1⁺ enriched spleen cells of normal WT, AML untreated (day 0), and ABT-737 treated (postday 33) mice immunoprobed with cyclin D1 and D3, p21^Waf1/Cip1, p15^INK4B, p27^Kip1, phospho-p38^MAPK, BCL-xL, MCL-1, and β-actin (control for loading) (n = 2 mice).