3001 Lung cancer detection by computer assisted analysis of novel biomarkers in induced sputum samples

Background & Objectives: Lung cancer (LC) is a lethal malignancy. Numer- ous studies attempted to improve the outcome of this disease. Lately, innovative technologies and growing knowledge of LC genetics expanded our possibilities. This study was aimed to test the feasibility of a computer assisted analysis of induced sputum (IS) for LC detection. Methods: IS was collected from 15 LC patients and 18 healthy controls. Samples were analyzed by morphology and Fluorescence in situ Hybridization (FISH) using the Duet scanning system (BioView, Rehovot, Israel). ∼3000 cells/sample were fixed, stained in Giemsa (Sigma, St Louis, MO), and scanned. Subsequently, cells were hybridized to a probe mixture for chromosomes 3p22.1 & 10q22-23 and their control centromeres, and scanned again. Scanning methods included: a) Target scan: selection of morphologically atypical cells and FISH analysis of these cells, and b) Area scan: random FISH analysis of 500 cells. Results: a) Target scan: 236±180 cells/sample were analyzed. The mean # of abnormal cells was 20.8±13.6 and 17.7±23.4 in 3p and 10q probes, respectively. Sensitivity was 91.7% and 58.3% and specificity was 88.9% and 80% for 3p and 10q probes, respectively. b) Area scan: the mean % of abnormal cells was 3.7±2.5 and 3.9±2.1 in 3p and 10q probes, respectively. Sensitivity was 54.5% and 81.8% and specificity was 80% and 82% for 3p and 10q probes, respectively. The combination of both methods yielded overall 100% sensitivity and 89% Previous studies have suggested a role for an increased apoptosis of the endothelial cells in the the alveolar septa in the pathogenesis of pulmonary emphysema. In animal models, circulating endothelial stem cells may contribute to the repair of lung damage. It is unknown if a decrease in the blood of these cells may contribute to the pathogenesis of pulmonary emphysema in humans. The aim of our study was to investigate by flow cytometry the number of total (CD34+) and endothelial stem (triple positive for CD34+/CD133/VEGF-R2) cells in the peripheral venous blood of age-matched smokers with or without pulmonary emphysema. The presence and the severity of pulmonary emphysema was determined using HRCT of the chest with density mask and the NETT score (0 to 4). Venous blood samples from 37 subjects (mean age: 66.8±1.4, 25M/12F, mean 33.11±3.2 pack-years, 12 current and 25 ex-smokers) were obtained. Their mean HRCT score is 1.7±0.4. 22 subjects (59.5%) had chronic airflow obstruction (mean post-bronchodilator FEV1/FVC ratio=56.8%±2.7) whereas 39.5% (n=15) had normal FEV1/FVC ratio(77.1%±1.4). We found a significant correlation between the absolute number of circulating CD34+ cells and the absolute number of circulating endothelial stem cells (r=0.593, p<0.0001). Also there was a significant correlation between the percentage of circulating endothelial stem cells and the number of pack-years smoked (r=0.42, p<0.05). No correlation was found between total and endothelial stem cells number and HRCT score of pulmonary emphysema or lung function data. These data suggest that the number of circulating endothelial stem cells is not related to pulmonary emphysema severity.