title: [Methylation of ER and ER gene and its significance in primary and relapsed/metastatic lesions of breast cancer].
abstract: OBJECTIVE
  To investigate the different expressions of ER and ER gene status between primary and relapsed/metastatic lesions and their clinical significance.
  
  
  METHODS
  ER and ER gene status of primary and relapse/metastatic breast cancer masked in 70 metastatic breast cancer patients were assessed by determination of methylation status by immunohistochemistry (IHC) and methylation specific polymerase chain reaction (MSP), respectively.
  
  
  RESULTS
  Positive rate of ER in the primary breast cancers was 64.3%, and in the relapse/metastatic lesions was 41.4% (P < 0.05). There were six patients whose positive ER status was changed to negative, among them the ER gene status was changed from demethylation to hypermethylation in four cases. Another four patients with negative ER status changed to positive, and their ER gene hypermethylation changed to ER demethylation status.
  
  
  CONCLUSIONS
  The discordance of ER expression status in primary and relapse/metastatic lesions of breast cancer might be related to DNA methylation status.
authors.affiliation: Department of Medical Oncology, Central Hospital of Xuzhou, the Cancer Institute of Southeast University, Xuzhou 221009, China.
authors.forename: Li
authors.initials: L
authors.lastname: Sun
authors.forename: Dahai
authors.initials: D
authors.lastname: Yu
authors.forename: Haitao
authors.initials: H
authors.lastname: Yin
authors.forename: Susheng
authors.initials: S
authors.lastname: Cao
authors.forename: Shichao
authors.initials: S
authors.lastname: Zhuo
authors.forename: Ling
authors.initials: L
authors.lastname: Wei
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Email: sunsanyuan120@163.com.
authors.forename: Sanyuan
authors.initials: S
authors.lastname: Sun
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018567:Breast Neoplasms, Male / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D019175:DNA Methylation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000556:secondary; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011960:Receptors, Estrogen / Q000235:genetics* / Q000378:metabolism
chemical_list: D011960:Receptors, Estrogen