title: Hiding in plain view: genetic profiling reveals decades old cross contamination of bladder cancer cell line KU7 with HeLa.
abstract: OBJECTIVE
  KU7 is a popular urothelial carcinoma cell line that was isolated from the bladder of a patient at Keio University in 1980. It has subsequently been widely used in laboratories around the world. We describe how routine cell line authentication revealed that KU7 was cross contaminated almost 30 years ago with HeLa, a cervical carcinoma cell line.
  
  
  METHODS
  Presumed KU7 clones dating from 1984 to 1999 were provided by M.D. Anderson Cancer Center, Vancouver Prostate Centre, Kyoto University, Tokyo Medical University and Keio University. HeLa was obtained from ATCC. Genomic DNA was isolated and short tandem repeat analysis was performed at the M.D. Anderson Cancer Center Characterized Cell Line Core Facility, Johns Hopkins University Fragment Analysis Facility and RIKEN BioResource Center, Ibaraki, Japan. Comparative genomic hybridization was performed on a platform (Agilent Technologies, Santa Clara, California) at Vancouver Prostate Centre.
  
  
  RESULTS
  The short tandem repeat profile of all KU7 clones was an exact match with that of HeLa. Comparative genomic hybridization of all samples revealed an abundance of shared chromosomal aberrations. Slight differences in some genomic areas were explained by genomic drift in different KU7 clones separated by many years.
  
  
  CONCLUSIONS
  Our analysis identified that cross contamination of KU7 with HeLa occurred before 1984 at the source institution. All KU7 clones in the urological literature should be considered HeLa and experimental results should be viewed in this light. Our results emphasize the need to authenticate cell lines in oncological research.
authors.affiliation: Vancouver Prostate Centre and Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Jäger
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Horiguchi
authors.forename: Jay
authors.initials: J
authors.lastname: Shah
authors.forename: Tetsutaro
authors.initials: T
authors.lastname: Hayashi
authors.forename: Shannon
authors.initials: S
authors.lastname: Awrey
authors.forename: Kilian M
authors.initials: KM
authors.lastname: Gust
authors.forename: Boris A
authors.initials: BA
authors.lastname: Hadaschik
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Matsui
authors.forename: Shawn
authors.initials: S
authors.lastname: Anderson
authors.forename: Robert H
authors.initials: RH
authors.lastname: Bell
authors.forename: Susan
authors.initials: S
authors.lastname: Ettinger
authors.forename: Alan I
authors.initials: AI
authors.lastname: So
authors.forename: Martin E
authors.initials: ME
authors.lastname: Gleave
authors.forename: I-Ling
authors.initials: IL
authors.lastname: Lee
authors.forename: Colin P
authors.initials: CP
authors.lastname: Dinney
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tachibana
authors.forename: David J
authors.initials: DJ
authors.lastname: McConkey
authors.forename: Peter C
authors.initials: PC
authors.lastname: Black
mesh_terms: D055028:Comparative Genomic Hybridization; D059018:DNA Contamination; D020869:Gene Expression Profiling; D006367:HeLa Cells; D006801:Humans; D013997:Time Factors; D001749:Urinary Bladder Neoplasms / Q000473:pathology
keywords: AMEL; DNA contamination; HeLa cells; KU; Keio University; M.D. Anderson Cancer Center; MDACC; STR; VPC; Vancouver Prostate Centre; aCGH; amelogenin; array comparative genomic hybridization; carcinoma; short tandem repeat; urinary bladder; urothelium