GSTP1 promoter hypermethylation is an early event in breast carcinogenesis

Virchows Arch. 2007 Jun;450(6):637-42. doi: 10.1007/s00428-007-0421-8. Epub 2007 May 4.


Promoter hypermethylation in precursor lesions of the breast cancer may be biomarkers of cancer risk and targets for cancer chemoprevention. Pi-class glutathione-S-transferases (GSTP1) is inactivated by promoter hypermethylation in invasive breast cancers. However, little is known about epigenetic silencing of GSTP1 gene by promoter hypermethylation in precursor lesions. To determine the significance of GSTP1 promoter hypermethylation in breast carcinogenesis, methylation status of GSTP1 gene was studied by nested methylation-specific polymerase chain reaction, and GSTP1 expression was studied by immunohistochemistry in invasive ductal carcinoma (IDC), ductal carcinoma in situ (DCIS), usual ductal hyperplasia (UDH), and normal breast tissue. GSTP1 promoter hypermethylation was detected in 4/24 (16.7%) of UDH, 18/49 (36.7%) of DCIS, and 14/36 (38.9%) of IDC. No hypermethylation was detected in normal breast tissues. GSTP1 promoter hypermethylation was found to be progressively elevated during breast carcinogenesis (p < 0.01). GSTP1 promoter hypermethylation was associated with loss of GSTP1 expression (p < 0.01 for UDH, p < 0.001 for DCIS and IDC). Our results suggest that GSTP1 promoter hypermethylation is an early event in breast carcinogenesis and appears to functionally silence GSTP1 expression. GSTP1 promoter hypermethylation in the precursor lesions of breast cancer may be used as a target for cancer chemoprevention.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Breast Neoplasms / genetics*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Carcinoma in Situ / genetics*
  • Carcinoma in Situ / metabolism
  • Carcinoma in Situ / pathology
  • Carcinoma, Ductal, Breast / genetics*
  • Carcinoma, Ductal, Breast / metabolism
  • Carcinoma, Ductal, Breast / pathology
  • DNA Methylation*
  • Female
  • Glutathione S-Transferase pi / genetics*
  • Glutathione S-Transferase pi / metabolism
  • Humans
  • Immunohistochemistry / methods
  • Neoplasm Invasiveness
  • Precancerous Conditions / genetics*
  • Precancerous Conditions / metabolism
  • Precancerous Conditions / pathology
  • Promoter Regions, Genetic*
  • Staining and Labeling
  • Time Factors
  • Tissue Distribution


  • GSTP1 protein, human
  • Glutathione S-Transferase pi