Detection of Mutations in Exons 5 and 8 of Tumor Suppressor Tp53 Gene in Patients with Squamous Cell Carcinoma of Lung Hospitalized in Afzalipour Hospital, Kerman, Iran

Introduction: Despite improvements in the diagnosis and treatment of lung cancer in the past two decades, it has remained the most common cause of death from cancer worldwide. Among all genes that are mutated in lung cancer, TP53 located on chromosome 17P13/1 has a significant diagnostic and prognostic value. TP53 mutations have been extensively studied in lung cancer and TP53 mutational spectra have been used for finding the origin(s) and mechanisms of these mutations in lung cancer development. The present study was conducted to investigate the TP53 mutations in patients with Non- small cell lung cancer hospitalized during 1997-2005 in Afzalipour Hospital, Kerman, Iran. Method: Formalin- fixed, Paraffin- embedded tissues from lung cancer patients undergone surgery between 1997 to 2005 were evaluated. The mutational status of the TP53 gene (exons 5 & 8) was screened by polymerase chain reaction (PCR) analysis followed by sequencing. Results: Of all cases of squamous cell carcinoma, 73 mutations were found in Exon 5 (in 18 cases) and 47 mutations in Exon 8 of TP53 gene (in 15 cases). we identified mutation hot spot at codons 6, 14, 25 of exon 5 and codons 2, 27, 35 of exon 8 of TP53 gene. Tansversions (G to T, A to T and G to C) and deletion mutations were the most in both exons 5 and 8. The incidence of G to T transversion mutations did not significantly differ between Exons 5 and 8. Conclusion: Higher prevalence of mutations in TP53 gene in the present study comparing to previous studies may be due to genetic, environmental and some epidemiological factors such as diet and life style of studied subjects