title: Expression of insulin-like growth factor-1 receptor in keloid and hypertrophic scar.
abstract: BACKGROUND
  Keloid and hypertrophic scar (HS) are two pathological forms of excessive dermal fibrosis, which are due to aberrant wound-healing responses. Accumulating evidence suggests that aberrant activity of growth factors and increased numbers of growth factor receptors play an important role in the formation of pathological scar.
  
  
  OBJECTIVE
  We examined the expression level of insulin-like growth factor-1 receptor (IGF-IR) in keloid, HS and normal skin.
  
  
  METHODS
  IGF-IR expression was analyzed by immunohistochemistry, real-time PCR and western blotting on tissues and fibroblasts from 30 patients, comprising 10 patients with keloid and 20 with HS (10 with immature and 10 with mature HS), and from 10 age-matched and sex-matched healthy controls.
  
  
  RESULTS
  Immunoreactivity to IGF-IR was found in dermal fibroblasts of keloid (90%), immature HS, (80%) and mature HS (30%), but not in normal skin. There was no statistically significant difference in immunoreactivity scores between keloid and immature HS, but there was a significant difference (P < 0.01) between mature and immature HS. Real-time PCR and western blot analysis confirmed that there was high expression of IGF-IR in keloid and immature HS fibroblasts, but not in mature HS or normal skin fibroblasts. IGF-IR was expressed in the overlying epidermis, and there was no significant difference between the groups.
  
  
  CONCLUSIONS
  IGF-IR may be involved in the pathogenesis of keloid and HS. Given that IGF-IR are predominantly expressed on dermal fibroblasts, targeting of IGF-IR in fibroblasts may be of benefit to prevent scarring.
authors.affiliation: Department of Burns, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Z-C
authors.initials: ZC
authors.lastname: Hu
authors.forename: B
authors.initials: B
authors.lastname: Tang
authors.forename: D
authors.initials: D
authors.lastname: Guo
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: Y-Y
authors.initials: YY
authors.lastname: Liang
authors.forename: D
authors.initials: D
authors.lastname: Ma
authors.forename: J-Y
authors.initials: JY
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D015153:Blotting, Western; D016022:Case-Control Studies; D017439:Cicatrix, Hypertrophic / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007627:Keloid / Q000378:metabolism*; D008297:Male; D060888:Real-Time Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism; D055815:Young Adult
chemical_list: D007334:Insulin-Like Growth Factor I