PO-373 Methylation deregulation of miRNAs promoters in breast cancer in very young women

摘要: Introduction Breast cancer has the highest incidence rate of all cancers in women worldwide. Although early breast generally an excellent prognosis, young is associated with a high risk systemic disease at long-term follow-up. Epigenetic modifications were reported to play important role many onsets. MiRNAs not only function as part epigenetic machinery, but are also epigenetically modified by DNA methylation. The aim current study analyse methylation alterations CpG miRNA encoding genes tumours occurring very (BCVY) ( 45 years old). Material and methods We analysed DNAmethylation 1264 miRNAs 26 BCVY samples 15 from BCO using ‘Illumina Infinium MethylationEPIC BeadChip’ array. Methylation differences assessed Wilcoxon Rank Sum test. Differences observed validated two independent populations: Flower et al 2015 Genome Caner Atlas (TCGA) datasets. Expression regulated sites differently methylated meta-analysis data ClariomD array, expression published Pena-Chilet 2014 TCGA gene data. perform validation real time-PCR expressed comparing older ones. Results discussions identified 193 significantly that regulating miRNAs. hypomethylated CpGs localised islands regions away them (opensea) mainly hypermethylated. could validate total 10 probes sets. Finally, mir-9–1, mir-184, mir-551b mir-196a-1 de-regulated comparison Conclusion differential profile BCVY. Most between age groups previously described aberrant cancer. Additionally, some presented significant different expression. present includes for first time analysis EPICarray large cohort women. four may be promising epi/genetic biomarkers risk.