title: Characterization and Prognostic Value of Mutations in Exons 5 and 6 of the p53 Gene in Patients with Colorectal Cancers in Central Iran.
abstract: OBJECTIVE
  We aimed to investigate the relation-ships among various mutations of the p53 gene and their protein products, histological characteristics, and disease prognosis of primary colorectal cancer in Isfahan, central Iran.
  
  
  METHODS
  Sixty-one patients with colorectal adenocarcinoma were enrolled in the study. Mutations of the p53 gene were detected by single-stranded conformation polymorphism and DNA sequencing. The protein stability was evaluated by immunohistochemistry. Patients were followed up to 48 months.
  
  
  RESULTS
  Twenty-one point mutations in exons 5 and 6 were detected in the tumor specimens of 14 patients (23%). Of those, 81% and 9.5% were missense and nonsense mutations, respectively. There were also two novel mutations in the intronic region between exons 5 and 6. In 11 mutated specimens, protein stability and protein accumulation were identified. There was a relationship between the type of mutation and protein accumulation in exons 5 and 6 of the p53 gene. The presence of the mutation was associated with an advanced stage of cancer (trend, p<0.009). Patients with mutated p53 genes had significantly lower survival rates than those with wild type p53 genes (p<0.01).
  
  
  CONCLUSIONS
  Mutations in exons 5 and 6 of the p53 gene are common genetic alterations in colorectal adenocarcinoma in central Iran and are associated with a poor prognosis of the disease.
authors.affiliation: Faculty of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran.
authors.forename: Rahim
authors.initials: R
authors.lastname: Golmohammadi
authors.forename: Mohammad J
authors.initials: MJ
authors.lastname: Namazi
authors.forename: Mehdi
authors.initials: M
authors.lastname: Nikbakht
authors.forename: Mohammad
authors.initials: M
authors.lastname: Salehi
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Derakhshan
keywords: Colorectal neoplasms; Missense; Nonsense; p53 gene mutation