title: [P53 gene mutation in gallbladder cancer].
abstract: BACKGROUND
  Gallbladder cancer frequency and mortality renders it one of the most important neoplastic diseases in Chile. P53 tumor suppressor gene has been studied in most types of cancer, but there is scarce information about it in gallbladder cancer.
  
  
  OBJECTIVE
  To study the frequency of P53 gene mutation in gallbladder cancer in the ninth region of Chile.
  
  
  METHODS
  In 25 pathological samples of gallbladder cancer, the direct amplification and sequencing of p53 gene exons 5,6,7,8-8 was possible.
  
  
  RESULTS
  Seventeen punctual mutations were observed in 13 cases (52%). There were 10 transitions, 5 transversions, one insertion (codon 194) and one deletion (codon 186). Eight cases had mutations in exon 5, six had mutations in exon 6, two had mutations in exon 7 and one had mutations in exons 8-9. In 14 of 25 cases, gene p53 protein was positive. When immunohistochemical expression of gene p53 protein was positive in more than 20% of cells, there was a high correlation between genetic alterations and immunohistochemical expression of the protein, with a specificity, sensitivity, positive and negative predictive values over 80%.
  
  
  CONCLUSIONS
  P53 gene mutation is observed in a high proportion of gallbladder cancers at it can be accurately detected with conventional immunohistochemical techniques. The importance of this gene in the genesis of this carcinoma should be determined studying preneoplastic lesions and early carcinomas.
authors.affiliation: Unidad de Anatomía Patológica y Citopatología Hospital Temuco, Chile.
authors.forename: I
authors.initials: I
authors.lastname: Roa
authors.forename: A
authors.initials: A
authors.lastname: Melo
authors.forename: J
authors.initials: J
authors.lastname: Roa
authors.forename: J
authors.initials: J
authors.lastname: Araya
authors.forename: M
authors.initials: M
authors.lastname: Villaseca
authors.forename: X
authors.initials: X
authors.lastname: de Aretxabala
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000235:genetics*; D000328:Adult; D000368:Aged; D005091:Exons / Q000235:genetics; D005260:Female; D005706:Gallbladder Neoplasms / Q000737:chemistry / Q000235:genetics*; D005784:Gene Amplification; D016158:Genes, p53 / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics
chemical_list: D016159:Tumor Suppressor Protein p53