Figure 1

DNA microarray analysis in AML cells during in vivo chemotherapy. AML blast viability was investigated in four patients sampled during in vivo chemotherapy. The expression of apoptosis related proteins were detected by Western blotting (P3, P4) (A). Expression of the pro-apoptotic protein BAX increased during therapy, suggesting initiation of cell death. However, no cleavage of the executioner protease pro-caspase-3 could be detected and this is in agreement with the flowcytometric analysis in (B). Apoptosis was measured using flowcytometric detection of Annexin-V FITC and propidium iodide staining (P1, P3) as described in Methods. No signs of apoptosis could be detected in the cells during the first six hours of therapy in either patient (B). Similar viability (~80%) was present at 18 h determined by analysis of nuclear morphology and cell scattering (data not shown). Early changes in gene expression of p53-associated genes were detected already 2–4 hours following induction therapy (C). The profiles of 27 of the 31 p53 associated genes are shown. Late response gene expression of p53-inducible genes was detected 18–24 hours after treatment induction (D). For abbreviations see Additional File 2. The dendrogram and heat maps show a Eucledian two-way cluster analysis based on the most consistently upregulated genes. Thus, genes that cluster together have a similar expression profile as a response to induction therapy. In the diagram the relative mRNA levels in the blasts before therapy are colored in green, and upregulated genes following standard chemotherapy treatment are shown in violet according to the color scale below.