title: The effect of silicone gel on basic fibroblast growth factor levels in fibroblast cell culture.
abstract: BACKGROUND
  Topical silicone gel has shown promise in the treatment of hypertrophic and keloid scars. However, its mechanism of action remains undetermined.
  
  
  OBJECTIVE
  To investigate whether the presence of silicone alters the secretion of basic fibroblast growth factor (bFGF), a key cytokine involved in the scar formation process.
  
  
  METHODS
  Serum-free fibroblast cell cultures were established from normal, keloid, and fetal skin, which heals without scarring, and exposed to silicone gel. Serial cell counts were performed, and supernatants were collected for bFGF quantification by enzyme-linked immunosorbent assay at 4, 24, 72, and 120 hours.
  
  
  RESULTS
  Growth curves were similar and no statistically significant differences in population doubling times were observed between treated and untreated specimens. Statistically significant differences in bFGF levels between treated and untreated normal fibroblasts were observed at 24, 72, and 120 hours after cell culture initiation. Differences in bFGF levels between treated and untreated fetal fibroblasts that approached statistical significance were observed at 72 and 120 hours.
  
  
  CONCLUSIONS
  These results suggest that silicone gel is responsible for increased bFGF levels in normal and fetal dermal fibroblasts. We postulate that silicone gel treats and prevents hypertrophic scar tissue, which contains histologically normal fibroblasts, by modulating expression of growth factors such as bFGF. Our data support the hypothesis that substances that favorably influence wound healing do so by correcting a deficiency or overabundance of the growth factors that orchestrate the tissue repair process.
authors.affiliation: Wound Healing and Tissue Engineering Laboratory, Division of Otolaryngology/Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA. hanasono@hotmail.com
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Hanasono
authors.forename: Joanne
authors.initials: J
authors.lastname: Lum
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Carroll
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Mikulec
authors.forename: R James
authors.initials: RJ
authors.lastname: Koch
mesh_terms: D000293:Adolescent; D000328:Adult; D018929:Cell Culture Techniques; D003879:Dermatologic Agents / Q000494:pharmacology*; D005260:Female; D005333:Fetus; D016222:Fibroblast Growth Factor 2 / Q000032:analysis / Q000096:biosynthesis / Q000187:drug effects*; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007627:Keloid / Q000378:metabolism; D020034:Silicone Gels / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects / Q000378:metabolism
chemical_list: D003879:Dermatologic Agents; D020034:Silicone Gels; D016222:Fibroblast Growth Factor 2