Clinicopathological and Molecular Biological Studies of Primary Pulmonary Carcinoma with the p53 Gene Mutations

Objective To investigate the relationship between p53 aberrations and human pulmonary carcinoma prognosis and to evaluate as a genetic marker in the prognostic significance of the P53 mutations in the lung cancer. Methods DNAs from normal (n=5) and tumor (n=31) tissue specimens from non-small cell lung carcinomas (NSCLC), p53 exons 5-8 mutations were analyzed by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis. Results The detected mutation rate is 48.4％ (15/31) in the pulmonary carcinoma group, which was significantly higher than that in the control group. The control group showed that there is no p53 mutations. In the pulmonary carcinoma group, detection rates of p53 exons 5-8 mutations for squamous cell carcinomas, adenocarcinomas, bronchioloalveolar carcinomas and large cell carcinomas were 56.3％, 30.0％, 33.3％ and 100.0％, respectively. The incidence of p53 point mutational activation in the adenocarcinomas was lower in pulmonary carcinomas as compared to that in the squamous cell carcinomas. The level of p53 gene mutations was associated with TNM stages, the mutations of p53 gene in cancer tissues of the stages Ⅲ -Ⅳ were higher than in tumor stage Ⅰ and/or stage Ⅱ (χ2=6.556, P=0.038). The mutations in poor differentiated tumors were obviously higher than well differentiated and moderately differentiated tumors (χ2=4.045, P=0.044; χ2=4.232, P=0.040, respectively). However, statistical analysis showed that there is no significant correlations between p53 mutations and other clinical parameters, such as: age, sex, tumor size, and histological subtypes. Conclusion Detection of p53 gene mutations in lung carcinomas by PCR-SSCP can be used as a follow-up intermediate biomarker for the prognostic surveillance of human pulmonary carcinoma.