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The oncogenic human papilloma viruses (HPVs) are associated with precancerous cervical lesions and development of cervical cancer. The DNA methylation signatures of host genome in normal, precancerous and cervical cancer tissue may indicate tissue-specific perturbation in carcinogenesis. The aim of this study was to identify new candidate genes that are differentially methylated in squamous cell carcinoma compared to the DNA samples from cervical intraepithelial neoplasia grade 3 (CIN3) and normal cervical scrapes. The Illumina Infinium Human Methylation 450 K BeadChip method identifies genome- wide DNA methylation changes in CpG islands, CpG shores and shelves. Our findings showed an extensive differential methylation signature in cervical cancer compared to the CIN3 or normal cervical tissues. The identified candidate biomarker genes for cervical cancer represent several types of mechanisms in the cellular machinery that are epigenetically deregulated by hypermethylation, such as membrane receptors, intracellular signaling and gene transcription. The results also confirm the extensive hypomethylation in cancer cells of genes in the immune system. These insights into the functional role of DNA methylome alterations in cervical cancer could be clinically applicable in diagnostics and prognostics, and may guide the development of new epigenetic therapies.

Aging is characterized by a profound remodeling of the epigenetic architecture in terms of DNA methylation patterns. To date the most effective tool to study genome wide DNA methylation changes is Infinium HumanMethylation450 BeadChip (Infinium 450k). Despite the wealth of tools for Infinium 450k analysis, the identification of the most biologically relevant DNA methylation changes is still challenging. Here we propose an analytical pipeline to select differentially methylated regions (DMRs), tailored on microarray architecture, which is highly effective in highlighting biologically relevant results. The pipeline groups microarray probes on the basis of their localization respect to CpG islands and genic sequences and, depending on probes density, identifies DMRs through a single-probe or a region-centric approach that considers the concomitant variation of multiple adjacent CpG probes. We successfully applied this analytical pipeline on 3 independent Infinium 450k datasets that investigated age-associated changes in blood DNA methylation. We provide a consensus list of genes that systematically vary in DNA methylation levels from 0 to 100 years and that have a potentially relevant role in the aging process.