Yang M, et al. - Researchers investigated potential DNA methylation-based markers as well as therapeutic targets for advanced-stage type 2 papillary renal cell carcinoma (PRCC). They used methylation data produced by The Cancer Genome Atlas (TCGA)'s kidney renal papillary cell carcinoma (TCGA-KIRP, 450k array) project in order to assess progressive DNA methylation alterations and copy number variation from localized to advanced-stage type 2 PRCC. As markers that could distinguish between localized and advanced-stage type 2 PRCC, 4 CpGs (cg00489401, cg27649239, cg20555674, and cg07196505) were identified in particular. Mostly occurrence of copy gain of PTK7 in advanced-stage type 2 PRCC was found in copy number analysis. Association of both the 4 CpG methylation alterations and PTK7 copy number gain, with patient survival, was evident. Overall, the possible utility of DNA methylation markers that distinguish between localized and advanced-stage type 2 PRCC was suggested as markers for disease staging or outcome, while PTK7 copy gain was viewed as a potential therapeutic target for advanced-stage type 2 PRCC. In PRCC patients, a link of stepwise methylation changes and copy number gain with disease stage was also seen.