Differential expression in Amela and Mela tumors of genes involved in pigmentation, differentiation and development of melanocytes.

<p>A. Microarray data as log2 for Amela and Mela tumors are shown in arbitrary units (a.u.). For these genes, ratio of gene expression as log2 Amela/Mela is < -1 (a) or between -1 and 0 (b) with p values < 0.05; for Pou3f2 (c), ratio of gene expression as log2 Amela/Mela is > 1 with p value < 0.05. B–C. Validation of expression of four genes (from A) by QRT-PCR in Amela and Mela tumors <i>ex vivo</i> (B) and of corresponding melanoma lines cultured <i>in vitro</i> (C). D–E. Relative expression of transcripts for <i>Mitf</i> (D) and for <i>Brn2/Pou3f2</i> (E) in induced Mela and Amela tumors <i>ex vivo</i>. Amela tumors are represented by white dotted bars and Mela tumors by black dotted bars. For <i>ex vivo</i> analysis (B, D, E) values were normalized to those for skins of control mice, 6 samples of each tumor and 4 skin samples were analyzed. For <i>in vitro</i> analysis (C), 3 different cDNA preparations from two Mela and 8 Amela tumor lines were used and values were normalized to those for B16F10 cells. ***p value < 0.001; **p value < 0.01; *p value < 0.05 (see methods).