Application Of P16 And MGMT Gene Hypermethylation Measurement In Detection Of NSCLC

Objective:To investigate the methylation status of P16 and MGMT in sputum obtained by bronchoscope of NSCLC and explore its diagnostic value. A valuable index for clinical diagnosis of NSCLC wish to be found.Methods:The methylation status of P16 and MGMT in 42 patients with NSCLC and 9 patients with lung benign lesions were detected by methylation specific PCR. The relationship of methylation status and lung cancer clinical features were analysised and the value of combined detection of two gene methylation were compared.Results:1. The methylation frequencies of 2 genes examined in 42 NSCLC cases were 59.5%(25/42) for P16,42.9%(18/42) for MGMT. The 9 patients with lung benign lesions were all unmethylated for P16 and MGMT genes. The methylation frequencies of P16 and MGMT in these specimens did not differ according to the clinical features:gender, age, pathological type and TNM stage.2. The sensitivity was 59.5%(25/42) for P16,42.9%(18/42) for MGMT. Evaluating the combined effect of methylation of at least one of the two genes in sputum increased the sensitivity to 76.2%(32/42).And the positive rate of combined detection was higher than of brush biopsy.Conclusion:1. The methylation frequencies of P16 and MGMT were found not significantly different to the non-small cell lung cancer patient's age, gender, TNM stage, or pathological type.2. Mathylation analysis of P16 and MGMT genes in sputum was better than brush biopsy. It may be a promising new molecular approach to diagnosis of NSCLC.