title: Frequency of p53 gene mutation and protein expression in oral squamous cell carcinoma.
abstract: OBJECTIVE
  To determine the frequency of p53 gene mutation and protein expression in Oral Squamous Cell Carcinoma (OSCC) and to establish correlation between the two.
  
  
  METHODS
  Analytical study.
  
  
  METHODS
  Histopathology Department and Molecular Biology Laboratory, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from May 2010 to May 2011.
  
  
  METHODS
  Thirty diagnosed cases of OSCC were selected by consecutive sampling. Seventeen were retrieved from the record files of the AFIP, and 13 fresh/frozen sections were selected from patients reporting to the Oral Surgery Department, Armed Forces Institute of Dentistry (AFID). Gene p53 mutation was analyzed in all the cases using PCRSSCP analysis. DNA was extracted from the formalin-fixed and paraffin-embedded tissue sections and fresh/frozen sections. DNA thus extracted was amplified by polymerase chain reaction. The amplified products were denatured and finally analyzed by gel electrophoresis. Gene mutation was detected as electrophoretic mobility shift. The immunohistochemical marker p53 was applied to the same 30 cases and overexpression of protein p53 was recorded.
  
  
  RESULTS
  Immunohistochemical expression of marker p53 was positive in 67% [95% Confidence Interval (CI) 48.7-80.9] of the cases. Mutations of the p53 gene were detected in 23% (95% CI 11.5-41.2) of the OSCC. No statistically significant correlation was found between p53 gene mutation and protein p53 expression (rs=-0.057, p=0.765).
  
  
  CONCLUSIONS
  A substantial number of patients have p53 gene mutation (23%) and protein p53 expression (67%) in oral squamous cell carcinoma (OSCC).
authors.affiliation: Department of Oral Pathology, Khyber College of Dentistry, Peshawar.
authors.forename: Nighat
authors.initials: N
authors.lastname: Ara
authors.affiliation: Department of Pathology, Combined Military Hospital (CMH), Lahore.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Atique
authors.affiliation: Department of Heamatology, Armed Forces Institute of Pathology (AFIP), Rawalpindi.
authors.forename: Sohaib
authors.initials: S
authors.lastname: Ahmed
authors.affiliation: Department of Oral and Maxillofacial Surgery, Combined Military Hospital (CMH), Peshawar.
authors.forename: Syed Gulzar
authors.initials: SG
authors.lastname: Ali Bukhari
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D016158:Genes, p53 / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics*; D009154:Mutation; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D016159:Tumor Suppressor Protein p53