Modification of signaling proteins after treatment. Western blot analysis showing dephosphorylation of proteins from spleen cells of (A) ERK1/2 and (B) AKT on day 0 and after ABT-737 treatment (postday 33), and normalized protein loading confirmed by probing for- β-actin (n = 2 mice). (C) Representative western blot analysis showing dephosphorylation of proteins of ppERK and pAKT of spleen cells after culturing (in triplicate) in vitro with vehicle (V), 10, 100, or 500 nM ABT-737 for 24 hours (n = 2 mice). (D) Nanoimmunoassay using the NanoPro (ProteinSimple) isoelectric focusing for detection of MEK signatures. Representative trace of spleen cells of WT FVB/N and AML untreated mice (day 0) and after ABT-737 treatment (postday 33) showing the dephosphorylated isoform pMEK2-3 and restoration of MEK2 expression (arrowed); histogram showing restoration of normal FVB/N signatures of the different isoforms after treatment. Each reaction was done in triplicate. Representative of at least 2 mice (n = 2) in each group.