OBJECTIVE: To evaluate aberrant methylation of the p16 promoter as a useful biomarker of lung cancer. METHODS: A modified methylation-specific semi-nested PCR was performed to detect p16 hypermethylation in the matched samples of tumor tissue, blood plasma and sputum derived from 51 cases of lung cancer patients. RESULTS: Hypermethylation of p16 promoter was demonstrated in 84.3% of the tumor tissues, 70.6% of the blood plasma and 76.5% of the sputum specimens, respectively. Only the patients whose tumor tissues had p16 hypermethylation exhibited aberrant methylation in their plasma and/or sputum specimens. Combining with cytological examination, 92.2% of the patients with lung cancer could be detected by p16 hypermethylation assay in both sputum and plasma samples. CONCLUSION: The results indicate that p16 hypermethylation in plasma and sputum identified by semi-nested PCR is a biomarker of lung cancer which can be useful as an auxillary diagnostic parameter.
OBJECTIVE: To evaluate aberrant methylation of the p16 promoter as a useful biomarker of lung cancer. METHODS: A modified methylation-specific semi-nested PCR was performed to detect p16 hypermethylation in the matched samples of tumor tissue, blood plasma and sputum derived from 51 cases of lung cancerpatients. RESULTS: Hypermethylation of p16 promoter was demonstrated in 84.3% of the tumor tissues, 70.6% of the blood plasma and 76.5% of the sputum specimens, respectively. Only the patients whose tumor tissues had p16 hypermethylation exhibited aberrant methylation in their plasma and/or sputum specimens. Combining with cytological examination, 92.2% of the patients with lung cancer could be detected by p16 hypermethylation assay in both sputum and plasma samples. CONCLUSION: The results indicate that p16 hypermethylation in plasma and sputum identified by semi-nested PCR is a biomarker of lung cancer which can be useful as an auxillary diagnostic parameter.