Validation of gene microarray data by real-time quantitative RT-PCR (qRT-PCR). Three genes were subjected to QRT-PCR in the mRNA from ten pairs of PCa and adjacent benign prostate tissues. The significant down-regulation of SOX7 and SOX10 and up-regulation of SOX9 were detected in PCa tissues (n = 10) than that in the corresponding adjacent benign prostate tissues (all P < 0.01). Relative expression ratio is defined as the expression levels of the gene to those of the internal reference gene, β-actin. The assays were carried out in triplicate and means ± standard deviations were plotted.