Tissue-specific CYP19 gene promoter usage in lung tumor and adjacent non-malignant tissues by multiplex RT-PCR. Significant differences in promoter usage were observed for promoters I.3, I.1, I.4 and I.7, indicating aberrant activation of promoters I.3, I.1, and I.7 in lung cancer. The horizontal line represents the median, the box encompasses the 25th to 75th percentile and error bars encompass the 10th to 90th percentile. *p<0.05, by Wilcoxon signed-ranks test.