title: Methylation status of the CpG islands in vitamin D and calcium-sensing receptor gene promoters does not explain the reduced gene expressions in parathyroid adenomas.
abstract: OBJECTIVE
  The exact mechanism causing decreased expression of the vitamin D receptor (VDR) and calcium-sensing receptor (CASR) genes in parathyroid adenoma is not known, but methylation of promoter regions is often detected during epigenetic downregulation of gene expression. We investigated whether epigenetic silencing is involved in the decreased expression of VDR and CASR.
  
  
  METHODS
  Real-time PCR and immunohistochemistry confirmed the downregulation of the VDR and CASR genes at transcriptional and translational levels. Bisulfite-converted DNA samples from parathyroid adenomas with control samples were analyzed for methylation in the promoter region of VDR and CASR genes.
  
  
  RESULTS
  There was no significant methylation in the promoter regions of VDR and CASR genes in parathyroid adenomatous tissues.
  
  
  CONCLUSIONS
  Methylation-mediated silencing of VDR and CASR promoter does not appear to be associated with reduced expression, indicating the involvement of other factors in specific suppression of VDR and CASR in parathyroid adenomas.
authors.affiliation: AssociateDepartment of Endocrinology, Postgraduate Institute of Medical Education and Research, Chandigarh, India 160012. bhadadask@rediffmail.com.
authors.forename: Shweta
authors.initials: S
authors.lastname: Varshney
authors.forename: Sanjay Kumar
authors.initials: SK
authors.lastname: Bhadada
authors.forename: Naresh
authors.initials: N
authors.lastname: Sachdeva
authors.forename: Ashutosh Kumar
authors.initials: AK
authors.lastname: Arya
authors.forename: Uma Nahar
authors.initials: UN
authors.lastname: Saikia
authors.forename: Arunanshu
authors.initials: A
authors.lastname: Behera
authors.forename: Sudhaker D
authors.initials: SD
authors.lastname: Rao
mesh_terms: D000236:Adenoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D000328:Adult; D018899:CpG Islands / Q000235:genetics*; D019175:DNA Methylation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000378:metabolism; D010282:Parathyroid Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D011401:Promoter Regions, Genetic; D018167:Receptors, Calcitriol / Q000235:genetics* / Q000378:metabolism; D044169:Receptors, Calcium-Sensing / Q000235:genetics* / Q000378:metabolism
chemical_list: D018167:Receptors, Calcitriol; D044169:Receptors, Calcium-Sensing