Microsatellite DNA instability in nasal cytology of COPD patients

Abstract

Genetic alterations in the microsatellite DNA level have been successfully detected in sputum samples of patients with COPD and have been shown to be disease specific. Furthermore, previous studies have shown that inflammation coexists in the nasal mucosa of patients with COPD. The aim of this study was to assess the presence of MSI in nasal cytological samples of patients with COPD comparing the results with sputum samples of the same individuals. Nasal brush samples, sputum samples obtained by induction, and peripheral blood from 20 patients with COPD were analyzed. DNA was extracted and analyzed for MSI using the following microsatellite markers: RH70958, D5S207, D6S344, D6S263, G29802, D13S71, D14S588, D14S292 and D17S250. Microsatellite analysis was also performed in 8 healthy nonsmokers. MSI was detected in the sputum samples of 7 patients with COPD (35%). In contrast, no microsatellite DNA instability was noted in the nasal cytological samples of the same COPD patients. In addition, no genetic alteration was detected in the control group. These results suggest that MSI is a specific finding for the target organ of COPD, i.e. the lungs, despite the fact that inflammation coexists in the nasal mucosa of COPD patients. Our study supports the hypothesis that MSI could be an index of the somaticacquired genetic alterations in the lungs of COPD patients.

Microsatellite DNA instability and COPD exacerbations

“…In agreement with the current authors' previous investigations [7,8,18], a significant proportion (50%) of COPD patients in the present study exhibited MSI in markers which are located closely to genes encoding for proteins possibly related to COPD pathogenesis. Moreover, six (33%) out of 18 subjects showed MSI in more than one marker (table 2).…”

“…First, COPD patients presented sputum MSI in different chromosomal regions compared with sputum from asthmatics [8]. Secondly, MSI was found in sputum but not in nasal cytological samples of COPD patients, despite the fact that inflammation coexists in the nasal mucosa of these patients [18]. The latter suggests that MSI in the markers studied is a specific finding for the target organ of COPD, i.e.…”

Microsatellite DNA instability in nasal polyposis

“…Although microsatellite genetic alterations have been reported in many inflammatory conditions, they have never, to our knowledge, been detected in diseases of the nose 24, 28. The aim of the present study is to test the hypothesis whether acquired somatic genome mutations play a role in the pathogenesis of nasal polyposis by assessing the presence of MSI and/or LOH in the nasal cytology of patients with this disease.…”

Upper airway. 3: Sinonasal involvement in chronic obstructive pulmonary disease

“…33 Gene expression alterations in relation to smoking are also similar in bronchial and nasal mucosa, 34 though a small study in 20 subjects examining the presence of sputum DNA microsatellite instability failed to find such changes simultaneously in the nose. 35 …”