title: Quantitative profiles of the mRNAs of ER-alpha and its novel variant ER-alpha36 in breast cancers and matched normal tissues.
abstract: OBJECTIVE
  The novel estrogen receptor-alpha (ER-alpha) variant ER-alpha36 is reported to be functional in the estrogen signaling pathway and is related to tamoxifen resistance in breast cancer. However, ER-alpha36 tends to be a favorable factor for survival in patients without tamoxifen therapy. To investigate the mechanisms behind this paradox, we determined the differences between the transcriptional profiles of ER-alpha36 and full-length ER-alpha (ER-alpha66) in breast cancers and matched normal tissues.
  
  
  METHODS
  We analyzed ER-alpha36 and ER-alpha66 messenger RNA (mRNA) levels in 74 pairs of breast cancers and matched normal tissues using a real-time quantitative polymerase chain reaction (PCR) assay, and correlated the results with their clinicopathological characteristics.
  
  
  RESULTS
  Breast cancers expressed lower ER-alpha36 mRNA levels than matched normal tissues regardless of their ER-alpha66 expression status. Down-regulation of ER-alpha36 mRNA was correlated with local progression, lymph node metastasis, and advanced cancer stage. The level of ER-alpha66 mRNA was lower in ER-alpha negative breast cancers compared with matched normal tissues. No differences in ER-alpha66 mRNA levels were observed during cancer progression.
  
  
  CONCLUSIONS
  Down-regulation of ER-alpha36 is associated with carcinogenesis and progression of breast cancer.
authors.affiliation: Cancer Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhen-zhen
authors.initials: ZZ
authors.lastname: Xu
authors.forename: Jian-ming
authors.initials: JM
authors.lastname: Sheng
authors.forename: Xiao-chen
authors.initials: XC
authors.lastname: Zhang
authors.forename: Hao-hao
authors.initials: HH
authors.lastname: Wang
authors.forename: Xiao-dong
authors.initials: XD
authors.lastname: Teng
authors.forename: Xiao-jiao
authors.initials: XJ
authors.lastname: Liu
authors.forename: Jiang
authors.initials: J
authors.lastname: Cao
authors.forename: Li-song
authors.initials: LS
authors.lastname: Teng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D017931:DNA Primers / Q000235:genetics; D015536:Down-Regulation; D047628:Estrogen Receptor alpha / Q000737:chemistry / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008875:Middle Aged; D009376:Neoplasms, Hormone-Dependent / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D012334:RNA, Neoplasm / Q000235:genetics* / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D047628:Estrogen Receptor alpha; D012333:RNA, Messenger; D012334:RNA, Neoplasm