Fig. 5

Heat maps of differentially expressed genes and assessment of their relative expression on qPCR and Western blot. Gene signatures associated to (a) adaptation (high viability), and (b) resistance (sustained proliferation) upon cytarabine exposure were identified by two-group comparison (q < 0.05) of Z138-CytNS vs. Z138-CytES, and Z138-CytES vs. Z138-CytR21, respectively. Red and blue colors indicate up- and down-regulated genes, respectively. c Assessment of relative SPIB, TCEA3 and FABP5 mRNA expression in Z138-CytNS, Z138-CytES and Z138-CyR cells. The relative mRNA expressions were assessed in the different Z138 subclones using TaqMan probe based RT-PCR and revealed up-regulation of all three genes for Z138-CytR cells compared to Z138-CytNS cells, although the difference was most prominent for SPIB. The data are normalized to the S18 reference gene, and the reference sample Z138-CytNS for each gene. * = p < 0.05 and ** = p < 0.01, with statistical significance determined using the Holm-Sidak method, with alpha = 0.05. Each row was analyzed individually, without assuming a consistent SD. d Representative (n = 3) western blot analysis of SPIB, TCEA3 and FABP5 proteins. GAPDH was used as loading control