Fig. 4.

Relative expression of AhR mRNA and AhR target genes in human tumor cell lines. Analysis of microarray data obtained from 1,036 human cancer cell lines (http://www.broadinstitute.org/ccle/home) is presented. a Data corresponding to the five lymphoid malignancies listed and five transcripts, including AhR and four of its putative targets, are displayed as a color-coded gene-by-sample heat map, with rows (genes) and columns (samples) sorted by hierarchical clustering [136]. b Microarray data for the same five lymphoid cancers were analyzed, and genes ranked by Pearson correlation between the level of AhR expression and that of four known AhR target genes, CYP1B1, NQO1, TIPARP, and AhRR. Permutation-based p values and the corresponding FDR-corrected q values are shown. c A Kolmogorov–Smirnov test was performed to assess the strength of the association between AhR and its four targets. The x-axis lists the genes in the human transcriptome sorted by their distance from AhR (from the closest, left, to the furthest, right). The position of the four AhR targets (red ticks) is significantly skewed toward the left-hand side of the list (permutation-based p value = 0.021) [137]