Intact AhR signaling in A375 melanoma cells.

<p>(A) Western blot comparing relative abundance of AhR in human A375 melanoma cells and mouse Hepa1c1c7 hepatoma cells; h and m indicate the position of human and mouse AhR isoforms, respectively. GAPDH is shown as an equal loading control. (B) qPCR analysis of CYP1A1 induction in A375 melanoma cells after 6, 12, and 24 hours of treatment with vehicle (0.1% v/v DMSO), or leflunomide at the indicated concentrations. Data are the mean ± SD of 3 independent experiments *** P<0.0001, ** P<0.001, * P<0.01. (C) Leflunomide-induces nuclear localization of the AhR. A375 cells were treated for 4 hours with DMSO or leflunomide (100 µM) and AhR localization was visualized. (D) AhR mRNA expression profile (Log₂, RMA) of 967 cancer cell lines. Expression profiles of AhR in melanoma cells are compared with liver cancer cells, which have high AhR expression. (E) Box and whisker plots (error bars: min/max expression) of cancer cell line encyclopedia AhR mRNA data for non-melanoma and melanoma extracted from (D). Expression of AhR in melanoma cells vs all other cancer cell types are indicated. The AhR mRNA abundance of the two cell lines used in the study, MDA-MB-435 and A375, are depicted by dashed lines.