Independent biological validation by Q-PCR. Serial representation of Q-PCR relative expression (2-ΔΔCt; log10) of a series of genes (identified by symbols and HUGO nomenclature) that were shown to be statistically differentially expressed in both microarray and Q-PCR (indicated in bold in Table 2). Results are displayed as circles for the mean 2-ΔΔCt and 95% confidence intervals (α = 0.05) computed on a series of cancerous samples, which correspond to the sample set previously used in microarray analysis (compare Additional data file 10). The color patch refers to the primary drug responses, either chemo-sensitive (in blue) or resistant (in red) of the corresponding patients. Diamonds show the relative expression levels measured on a new tumor sample (T-P61) from an additional patient (P61). The results obtained for a second new patient are presented in Additional data file 7.