title: Determination of O⁶-methylguanine DNA methyltransferase promoter methylation in non-small cell lung cancer.
abstract: Aberrant methylation of promoter CpG islands is known to be a major inactivation mechanism of the tumor-related genes including DNA repair genes. The objective of this study was to determine the frequency of promoter methylation of the O⁶-methylguanine DNA methyltransferase (MGMT) gene as a DNA repair gene in nonsmall cell lung cancer (NSCLC) and to analyze the correlation with clinicopathological parameters including age, gender, smoking status, histological subtype, and clinical stage. Eighty patients with NSCLC were included in this study. The analysis of DNA methylation was performed on formalin-fixed, paraffin-embedded lung cancer tissues. Following DNA isolation and bisulfite treatment, DNA methylation was analyzed by methylation-specific real-time polymerase chain reaction. MGMT promoter methylation was detected in 51 of 80 (64%) NSCLC patients. There was a significant correlation between MGMT methylation and tumor stage (p = 0.01). The frequencies of the promoter methylation of MGMT gene in smokers and older patients were higher than in their counterparts. In conclusion, the present study provides strong evidence for a higher frequency of promoter methylation of the MGMT gene in NSCLC, indicating that it is a common event during the carcinogenesis of NSCLC.
authors.affiliation: Department of Medical Biology, School of Medicine, Pamukkale University, Doktorlar Cad. Kat:3, Bayramyeri, Denizli, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ekim
authors.forename: Vildan
authors.initials: V
authors.lastname: Caner
authors.forename: Nur
authors.initials: N
authors.lastname: Büyükpınarbaşılı
authors.forename: Emre
authors.initials: E
authors.lastname: Tepeli
authors.forename: Levent
authors.initials: L
authors.lastname: Elmas
authors.forename: Gülseren
authors.initials: G
authors.lastname: Bağcı
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D019175:DNA Methylation / Q000235:genetics*; D015254:DNA Modification Methylases / Q000235:genetics* / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000235:genetics* / Q000378:metabolism; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic / Q000235:genetics*; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D025521:Tumor Suppressor Proteins; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D045643:DNA Repair Enzymes