title: Prohibitin expression is associated with high grade breast cancer but is not a driver of amplification at 17q21.33.
abstract: In a study of ductal carcinoma in situ of the breast, we identified five genes at chromosome 17q21.33 that were over-expressed in high grade cases, and showed a correlation between expression and gene copy number. The aim of this study was to investigate potential drivers of genomic amplification at 17q21.33.
  
  
  
  Analysis of high resolution comparative genomic hybridisation and published data specified a minimum region of amplification at 17q21.33. Prohibitin (PHB) expression was examined by immunohistochemistry in 285 invasive breast cancers. Gene copy number was examined by fluorescence in situ hybridisation.
  
  
  
  The minimum region of amplification at 17q21.33 included ten genes with PHB selected as a candidate driver. Increased PHB expression was associated with higher grade breast cancer and poorer survival. Amplification of PHB was detected in 13 of 235 cases (5.5%) but was not associated with PHB expression. PHB amplification was most common in the ERBB2+ breast cancer subtype, although high expression was most prevalent in basal-like and luminal B cancers.
  
  
  
  Amplification at 17q21.33 is a recurrent feature of breast cancer that forms part of a 'firestorm' pattern of genomic aberration. PHB is not a driver of amplification, however PHB may contribute to high grade breast cancer.
authors.affiliation: *Sydney Medical School - Westmead, University of Sydney, Westmead †Westmead Institute for Cancer Research, Westmead ‡Westmead Millennium Institute, Westmead §Tissue Pathology, Institute of Clinical Pathology and Medical Research, Westmead Hospital, Westmead ||Translational Oncology, Sydney West Cancer Network, Western Sydney and Nepean Blue Mountains Local Health Districts, Westmead ¶Anatomical Pathology, St Vincent's Hospital, Darlinghurst **Prince of Wales Clinical School, University of New South Wales, Randwick ††School of Medical Sciences University of New South Wales, Randwick ‡‡School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia §§Genetics Branch, National Cancer Institute, Bethesda MD USA ||||these authors contributed equally to this work.
authors.forename: Lucy R
authors.initials: LR
authors.lastname: Webster
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Provan
authors.forename: Dinny J
authors.initials: DJ
authors.lastname: Graham
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
authors.forename: Robert L
authors.initials: RL
authors.lastname: Walker
authors.forename: Sean
authors.initials: S
authors.lastname: Davis
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Salisbury
authors.forename: Adrienne L
authors.initials: AL
authors.lastname: Morey
authors.forename: Robyn L
authors.initials: RL
authors.lastname: Ward
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Hawkins
authors.forename: Christine L
authors.initials: CL
authors.lastname: Clarke
authors.forename: Paul S
authors.initials: PS
authors.lastname: Meltzer
authors.forename: Rosemary L
authors.initials: RL
authors.lastname: Balleine
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002886:Chromosomes, Human, Pair 17; D005260:Female; D005784:Gene Amplification; D018628:Gene Dosage; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D000091402:Prohibitins; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C000717328:PHB protein, human; D000091402:Prohibitins; D012097:Repressor Proteins