Methylation Status of Vitamin D Receptor Gene Promoter in Benign and Malignant Adrenal Tumors

Autor: Catia Pilon, Andrea Rebellato, Riccardo Urbanet, Vincenza Guzzardo, Rocco Cappellesso, Hironobu Sasano, Ambrogio Fassina, Francesco Fallo
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: International Journal of Endocrinology, Vol 2015 (2015)
Druh dokumentu: article
ISSN: 1687-8337
1687-8345
DOI: 10.1155/2015/375349
Popis: We previously showed a decreased expression of vitamin D receptor (VDR) mRNA/protein in a small group of adrenocortical carcinoma (ACC) tissues, suggesting the loss of a protective role of VDR against malignant cell growth in this cancer type. Downregulation of VDR gene expression may result from epigenetics events, that is, methylation of cytosine nucleotide of CpG islands in VDR gene promoter. We analyzed methylation of CpG sites in the VDR gene promoter in normal adrenals and adrenocortical tumor samples. Methylation of CpG-rich 5′ regions was assessed by bisulfite sequencing PCR using bisulfite-treated DNA from archival microdissected paraffin-embedded adrenocortical tissues. Three normal adrenals and 23 various adrenocortical tumor samples (15 adenomas and 8 carcinomas) were studied. Methylation in the promoter region of VDR gene was found in 3/8 ACCs, while no VDR gene methylation was observed in normal adrenals and adrenocortical adenomas. VDR mRNA and protein levels were lower in ACCs than in benign tumors, and VDR immunostaining was weak or negative in ACCs, including all 3 methylated tissue samples. The association between VDR gene promoter methylation and reduced VDR gene expression is not a rare event in ACC, suggesting that VDR epigenetic inactivation may have a role in adrenocortical carcinogenesis.
Databáze: Directory of Open Access Journals