1.Characterization and Prognostic Value of Mutations in Exons 5 and 6 of the p53 Gene in Patients with Colorectal Cancers in Central Iran.
Rahim GOLMOHAMMADI ; Mohammad J NAMAZI ; Mehdi NIKBAKHT ; Mohammad SALEHI ; Mohammad H DERAKHSHAN
Gut and Liver 2013;7(3):295-302
BACKGROUND/AIMS: 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.
Adenocarcinoma
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Codon, Nonsense
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Colorectal Neoplasms
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Exons
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Genes, p53
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Humans
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Immunohistochemistry
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Introns
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Iran
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Point Mutation
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Prognosis
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Protein Stability
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Sequence Analysis, DNA
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Survival Rate