Mariana Bisarro dos Reis, Caroline Moraes Beltrami, Luiz Paulo Kowaslki and Silvia Regina Rogatto*
Genetic and epigenetic alterations have been associated with cancer development and progression. Important epigenetic modifications include posttranslational histone changes, covalent modifications of DNA bases and non-coding RNAs. Welldifferentiated thyroid carcinomas comprise papillary and follicular carcinomas, the most common subtypes. Methylation of thyroid-specific genes, including NIS and TSHR, genes involved in PI3K and MAPK pathways, as well as the tumor suppressor genes RASSF1A and PTEN and altered expression of microRNAs have been frequently reported in literature. Novel technologies using genome-wide approaches have contributed in revealing new epigenetically regulated genes involved in the molecular biology of thyroid cancer. The comprehensive analysis of genetic mutations, changes in DNA methylation, microRNA expression and posttranslational histone changes in thyroid carcinoma is critical to understand the crosstalk between these alterations and gene regulation that contributes to the development of diagnostic and prognostic tools, as well as new therapeutic strategies. The focus of this review is to present and discuss the current knowledge of molecular epigenetic data and their impact on thyroid carcinoma.
