Figure 4
Association between methylation and mRNA expression of LINE-1 elements in stage IIIC CM patients. Short-term cultures of CM cells generated from neoplastic lesions of 42 stage IIIC melanoma patients were evaluated for LINE-1 methylation at 3 CpG sites (CpG1, CpG2, CpG3) and for LINE-1 mRNA expression by bisulfite pyrosequencing and quantitative RT-PCR analyses, respectively. All cells were analyzed at 6th in vitro passage. Methylation at each investigated LINE-1 CpG site is reported as %, level of LINE-1 mRNA expression is reported relative to the value measured in PBMC obtained from healthy donors, used as reference. Correlation between LINE-1 methylation and mRNA expression was evaluated by Spearman's rank correlation test, reported P values were two sided.