Abstract A36: Quantitative determination of methylation patterns in FHIT and APC genes in NSCLC: comparative analysis in tumor and normal lung tissue, peripheral blood, sputum and bronchial aspirate

Abstract

Abstract Introduction and objective. Quantifying and comparing the degree of methylation in the promoter region of APC gene and coding region of FHIT gene in patients (p) with non small cell lung cancer (NSCLC) in different samples. Correlate these methylation patterns with clinical variables. Methods. DNA was extracted from peripheral blood simples (B), sputum (S) and bronchial aspirate (BA), obtained from patients with NSCLC prior to the completion of surgery, as well as resected lung tumor tissue (TT) and normal lung tissue (TN). Methylation patterns were analyzed by bisulfito conversion and subsequent pyrosequencing (QIagen PyroMark System).We analyzed 5 CpG islands in the promoter region of the APC gene and 5 CpG islands in the coding region of the FHIT gene. Results: We analyzed 20p, with a median age of 64 years (range 48-70), 16 men and 4 women. Smoking status: 2p never smokers, 11p former smokers, 7p current smokers. Histology: 10p adenocarcinoma, 9p squamous, 1p large cell. Stage: I 8p, II 8p, III 4p. No statistically significant differences were observed between the samples studied to any of the islands analyzed. The degree of methylation in TT CpG1 was higher in smokers and former smokers <5 years, compared to never smokers and ex-smokers >5 years, mean 4 (0-10) vs 0, p=0.022. There was no other difference when analyzing the degree of methylation as a function of the variables age, sex, smoking status, cumulative tobacco consumption, histological type and clinical stage. Respect FHIT gene, no statistically significant differences were found between the tissues studied respect to any of the CpG islands analyzed and likewise, no differences were observed when analyzed for degree of methylation depending on the clinical variables studied. Conclusions. The area of the APC gen promoter and FHIT coding region analyzed showed a low degree of methylation, with no significant difference observed between the samples studied. The degree of methylation in the TT CpG1 island of the APC gene was higher in current smokers and former smokers <5 years. However, these findings have to be confirmed in a larger sample. *This study was funded by the Carlos III Health Institute (PS09/00308), Spain. Note: This abstract was not presented at the conference. Citation Format: Rocio Lavado-Valenzuela, Sr., Carlos Pagés, Sr., Roberto Mongil, Sr., Francisco Páez, Sr., Enrique Bermejo, Sr., Miguel Angel Berciano, Sr., Dolores Bautista, Sr., Cynthia Robles, Jr., Ricardo Arrabal, Sr., Jose Luis De la Cruz, Sr., Manuel Benavides, Sr., Manuel Cobo, Sr.. Quantitative determination of methylation patterns in FHIT and APC genes in NSCLC: comparative analysis in tumor and normal lung tissue, peripheral blood, sputum and bronchial aspirate. [abstract]. In: Proceedings of the Third AACR International Conference on Frontiers in Basic Cancer Research; Sep 18-22, 2013; National Harbor, MD. Philadelphia (PA): AACR; Cancer Res 2013;73(19 Suppl):Abstract nr A36.