Single CpG island methylation is not sufficient to maintain the silenced expression of CASPASE-8 apoptosis-related gene among women with epithelial ovarian cancer
Nenhuma Miniatura disponível
Data
2014-02-01
Autores
Braga, Leticia da Conceicao [UNESP]
Silva, Luciana Maria
Alvares da Silva Ramos, Ana Paula
Piedade, Josiane Barbosa
Teixeira Vidigal, Paula Vieira
Traiman, Paulo [UNESP]
Silva Filho, Agnaldo Lopes da [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Resumo
Despite impressive research efforts, the biology of epithelial ovarian cancer (EOC) remains poorly understood and alterations in the expression of CASPASE-8 contribute to a worse tumor prognosis. This study assesses the methylation of the CpG island within the CASPASE-8 promoter and CASPASE-8 gene expression both in cystadenoma tumors and in primary and metastatic EOC. DNA and RNA were obtained from women with normal ovarian tissues (n = 18), ovarian serous cystadenoma tumors (n = 11) and EOC (n = 16) using Trizol (R). The methylation frequency of the CpG island in the CASPASE-8 promoter was assessed using the methylation-specific PCR assay after DNA bisulfite conversion. Quantitative PCR was performed to quantify the relative levels of CASPASE-8 in each sample. The differences between samples with each group were evaluated using the Mann-Whitney U and Kruskal-Wallis tests as indicated. Hemimethylation of the CASPASE-8 promoter was found in 11.8% of the normal ovary samples, 20% of the cystadenoma tumors and 20% of the metastatic EOC, while methylation of the CASPASE-8 promoter was absent in the EOC primary tissues (P = 0.047). An increased CASPASE-8 expression level was observed in all tumor groups. Significant differences were observed in the CASPASE-8 expression levels when compared with all ovarian tumor groups (P = 0.0278). Promoter DNA methylation did not associate with expression levels of CASPASE-8, suggesting the presence of other mechanisms in relation to gene expression control in EOC; thus providing a better understanding of this complex disease. (C) 2013 Elsevier Masson SAS. All rights reserved.
Descrição
Palavras-chave
Epithelial ovarian cancer, CASPASE-8, Expression
Como citar
Biomedicine & Pharmacotherapy. Paris: Elsevier France-editions Scientifiques Medicales Elsevier, v. 68, n. 1, p. 87-91, 2014.