title: Needle and surgical biopsy techniques differentially affect adipose tissue gene expression profiles.
abstract: BACKGROUND
  Adipose tissue gene expression analysis in humans now provides a tremendous means to discover the physiopathologic gene targets critical for our understanding and treatment of obesity. Clinical studies are emerging in which adipose gene expression has been examined in hundreds of subjects, and it will be fundamentally important that these studies can be compared so that a common consensus can be reached and new therapeutic targets for obesity proposed.
  
  
  OBJECTIVE
  We studied the effect of the biopsy sampling methods (needle-aspirated and surgical) used in clinical investigation programs on the functional interpretation of adipose tissue gene expression profiles.
  
  
  METHODS
  A comparative microarray analysis of the different subcutaneous adipose tissue sampling methods was performed in age-matched lean (n = 19) and obese (n = 18) female subjects. Appropriate statistical (principal components analysis) and bioinformatic (FunNet) functional enrichment software were used to evaluate data. The morphology of adipose tissue samples obtained by needle-aspiration and surgical methods was examined by immunohistochemistry.
  
  
  RESULTS
  Biopsy techniques influence the gene expression underlying the biological themes currently discussed in obesity (eg, inflammation, extracellular matrix, and metabolism). Immunohistochemistry experiments showed that the easier to obtain needle-aspirated biopsies poorly aspirate the fibrotic fraction of subcutaneous adipose tissue, resulting in an underrepresentation of the stroma-vascular fraction.
  
  
  CONCLUSIONS
  The adipose tissue biopsy technique is an important caveat to consider when designing, interpreting, and, most important, comparing microarray experiments. These results will have crucial implications for the clinical and physiopathologic understanding of human obesity and therapeutic approaches.
authors.affiliation: INSERM, Nutriomique U872 Team 7, Paris, France. dmmutch_sci@hotmail.com
authors.forename: David M
authors.initials: DM
authors.lastname: Mutch
authors.forename: Joan
authors.initials: J
authors.lastname: Tordjman
authors.forename: Véronique
authors.initials: V
authors.lastname: Pelloux
authors.forename: Blaise
authors.initials: B
authors.lastname: Hanczar
authors.forename: Corneliu
authors.initials: C
authors.lastname: Henegar
authors.forename: Christine
authors.initials: C
authors.lastname: Poitou
authors.forename: Nicolas
authors.initials: N
authors.lastname: Veyrie
authors.forename: Jean-Daniel
authors.initials: JD
authors.lastname: Zucker
authors.forename: Karine
authors.initials: K
authors.lastname: Clément
mesh_terms: D000328:Adult; D001706:Biopsy / Q000295:instrumentation / Q000379:methods*; D001707:Biopsy, Needle / Q000295:instrumentation / Q000379:methods; D016022:Case-Control Studies; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009765:Obesity / Q000235:genetics* / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis; D025341:Principal Component Analysis; D013851:Thinness / Q000235:genetics / Q000473:pathology