title: Analysis of APC allelic imbalance/loss of heterozygosity and APC protein expression in cutaneous squamous cell carcinomas.
abstract: BACKGROUND
  The adenomatous polyposis coli (APC) gene is a tumor suppressor gene which is mutated in the hereditary disease, familial adenomatous polyposis (FAP). Somatic mutations of the APC gene have also been identified in the majority of sporadic colorectal carcinomas, and mutation of the APC gene appears to be an early step in the initiation of colon cancer. Loss of heterozygosity (LOH) of APC has been described in a variety of other cancer types, including renal cell carcinoma, gastric cancer, non-small cell lung cancer, endometrial cancer and oral squamous cell carcinomas (SCC).
  
  
  OBJECTIVE
  To determine the role played by APC gene in the genesis of cutaneous SCC.
  
  
  METHODS
  Allelic imbalance/loss of heterozygosity (AI/LOH) was examined in twenty-two histologically confirmed cutaneous squamous cell carcinomas (SCC) using microsatellite markers, proximal to the APC gene. Immunohistochemical analysis of APC protein expression was also examined in the cutaneous SCC.
  
  
  RESULTS
  AI/LOH was detected in 60% of the SCC samples using D5S346 marker (proximal to the APC gene). Ninty-five percent of the SCC samples showed positive reduced APC expression, however the localization of the APC protein was abnormal.
  
  
  CONCLUSIONS
  The abnormal expression of APC suggests that APC gene may play a role in cutaneous SCC development.
authors.affiliation: Pathology Department, Royal College of Surgeons in Ireland and Beaumont Hospital, Dublin, Ireland.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Gray
authors.forename: Elaine W
authors.initials: EW
authors.lastname: Kay
authors.forename: Mary
authors.initials: M
authors.lastname: Leader
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mabruk
mesh_terms: D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics* / Q000378:metabolism; D000483:Alleles; D001483:Base Sequence; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D017931:DNA Primers; D006801:Humans; D007150:Immunohistochemistry; D019656:Loss of Heterozygosity; D016133:Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics*
chemical_list: C555337:APC protein, human; D025601:Adenomatous Polyposis Coli Protein; D017931:DNA Primers