Supporting Information Figure S1 Comparative expression between microarray and qRT-PCR for 12 candidate genes. Plotted are the mean fold-change values for 5 cell lines with the highest expression differences before and after 5Aza-dC treatment. (PDF) Figure S2 UCSC browser for localisation of the ampli- cons used for the Epityper assays. The alignments show the localisation of the Illumina probes. (PDF) Figure S3 Distribution of the melanoma cell lines according to their methylation status for a. COL1A2 mRNA expression, b. TNFRSF10D mRNA expression, c. THBS1 mRNA and protein expression, d. UCHL1 mRNA and protein expression. The melanoma cell lines were grouped following their methylation profiles: high (.50%), medium (20–50%) and no/low (0–20%). (PDF) Figure S4 Epityper results for the COL1A2, THBS1, TNFRSF10D and UCHL1 promoters in melanocytes, 45 melanoma cell lines, 30 fresh melanoma tumors and cell lines from other tumor types (colon, esophageal and glioma). 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(2006) CpG island methylation of genes accumulates during the adenoma progression step of the multistep pathogenesis of colorectal cancer. Genes Chromosomes Cancer 45: 781–789. PLoS ONE | www.plosone.org 8 October 2011 | Volume 6 | Issue 10 | e26121