Oxidative stress in cystic fibrosis patients with Burkholderia cenocepacia airway colonization: relation of 8-isoprostane concentration in exhaled breath condensate to lung function decline.

The association between oxidative stress and neutrophilic inflammation in cystic fibrosis (CF) lung disease is well recognized. 8-Isoprostane is a product of non-enzymatic oxidation of arachidonic acid. The aim of the present study was to examine the relationship between lung function decline and 8-isoprostane concentrations in exhaled breath condensate (EBC) in CF patients with Burkholderia cenocepacia airway colonization. Concentrations of 8-isoprostane in EBC were measured in 24 stable CF patients with B. cenocepacia airway colonization. The median (interquartile range) age of the cohort was 23.9 (22.0; 26.6) years. All patients underwent clinical examinations and pulmonary function tests at the time of EBC collection and in 1-, 3-, and 5-year intervals. 8-Isoprostane concentrations in EBC correlated to 1- and 3-year declines of forced expiratory volume in 1 s (FEV1) with r(S) values of -0.511 (p = 0.0011) and -0.495 (p = 0.016), respectively. In multiple regression analysis, 8-isoprostane concentrations in EBC were the only independent predictor for 1-year FEV1 decline (p = 0.01). When the median value of 8-isoprostane concentration in EBC (10.0 pg/mL) was used as a cutoff, subgroups of patients with lower and higher level of oxidative stress had significantly different median (interquartile range) FEV1 declines in 1-year interval, -2.4% (-5.3; 0.8) and -7.3% (-10.3; -5.8) predicted (p = 0.009). In conclusion, 8-isoprostane concentrations in EBC correlated to short-term lung function decline in CF patients with B. cenocepacia airway colonization. This correlation reflects the role of oxidative stress in CF lung pathogenesis and contributes to prediction of prognosis in these patients.

[Examination of exhaled breath condensate in cystic fibrosis]. / Vysetrení kondenzátu vydechovaného vzduchu u cystické fibrózy.

Examination of exhaled breath condensate belongs to experimental methods that are used in many pulmonary diseases and it can take part in the study of their pathophysiology. Its contribution to diagnostics and to monitoring of response to treatment is also evaluated. Many biomarkers of inflammation and oxidative stress were studied in exhaled breath condensate in cystic fibrosis. Examination of pH of exhaled breath condensate is considered to be useful in evaluation of inflammatory acidification of airways, together with evaluation of response to antibiotic treatment of pulmonary exacerbation, due to immediately accessible result. Other important biomarkers include 8-isoprostane and 3-nitrotyrosine as markers of oxidative stress (both with negative correlation with pulmonary function) and leukotriene B4 as marker of neutrophilic inflammation. Opposite to other pulmonary diseases, hydrogen peroxide does not belong to useful markers of oxidative stress in cystic fibrosis, due to abundant reduced thiols and glutathione peroxidase in sputum of these patients. Attempts to detect bacterial DNA in exhaled breath condensate in cystic fibrosis also failed. In spite of mentioned progress, examination of exhaled breath condensate remains a research method and it has not been introduced into clinical practice.

Multicenter phase II trial of YM155, a small-molecule suppressor of survivin, in patients with advanced, refractory, non-small-cell lung cancer.

PURPOSE: To evaluate the antitumor activity and safety of YM155, a novel, small-molecule suppressor of survivin, as single-agent therapy in patients with previously treated, advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with stage IIIb/IV NSCLC who had experienced treatment failure during one or two prior chemotherapy regimens (at least one of which was platinum based) received YM155 as a continuous intravenous infusion (4.8 mg/m(2)/d) over 168 hours followed by observation for 14 days in 21-day treatment cycles. The primary end point was objective tumor response rate (ORR). Secondary end points included duration of stable disease (SD), progression-free survival (PFS), overall survival (OS), safety and pharmacokinetic profiles, and pharmacodynamic evaluations. RESULTS: Thirty-seven patients received YM155. Two patients achieved a confirmed partial response, with an ORR of 5.4% (95% CI, 0.7% to 18.2%). An additional 14 patients (37.8%) achieved SD resulting in a disease control rate of 43.2% (95% CI, 27.1% to 60.5%). Median duration of PFS was 1.7 months (95% CI, 1.3 to 2.8 months). Median duration of OS was 6.6 months (95% CI, 4 to 12.2 months), with a 1-year survival rate of 35.1%. Treatment with YM155 was well tolerated with the majority of treatment discontinuations not treatment related. CONCLUSION: YM155 exhibited modest single-agent activity in patients with refractory, advanced NSCLC. A favorable safety/tolerability profile was reported. Further evaluation of YM155 in combination with chemotherapy and other targeted agents may be warranted.

Loss of heterozygosity and human telomerase reverse transcriptase (hTERT) expression in bronchial mucosa of heavy smokers.

BACKGROUND: Lung carcinogenesis is a multistep process of accumulation of genetic changes, including loss of heterozygosity (LOH), and precedes phenotypic transformation of the bronchial mucosa. The activity of telomerase, correlating with the hTERT mRNA expression, is detectable in a majority of neoplasms. In this study, the frequency of LOH and hTERT expression in bronchial mucosa of heavy smokers in bronchoscopic biopsies was analyzed. METHODS: LOH was examined in 122 bronchial specimens from 81 smokers (67 normal mucosa/bronchitis, 12 squamous metaplasia, 28 dysplasia, 15 bronchogenic carcinoma specimens) by polymerase chain reaction (PCR) and capillary electrophoresis by using 7 fluorescence-labeled markers matching 5 chromosomal regions. hTERT expression was analyzed in 87 specimens (45 normal mucosa/bronchitis, 12 squamous metaplasia, 18 dysplasia, 12 bronchogenic carcinoma specimens) by real-time quantitative reverse-transcription PCR. RESULTS: LOH was detected in at least 1 chromosomal region in 51 of 122 (41.8%) specimens; the incidence in normal bronchial mucosa and preneoplastic lesions was similar (20%-40%); a substantial rise (87%) occurred in carcinomas. The median normalized hTERT(N) values were 6.67 in normal epithelium/chronic bronchitis, 18.38 in squamous metaplasia, 13.31 in epithelial dysplasia, and 75.46 in carcinomas. These results were significantly different (P=.0036). With an increasing number of LOH, the median value of hTERT(N) expression rose, but hTERT was expressed also in tissue samples without any LOH detection. CONCLUSIONS: Results indicated that hTERT expression, together with LOH, represent early events in lung carcinogenesis, as both were detected in precancerous lesions and in normal epithelium of heavy smokers.

Double-blind, placebo-controlled, randomized phase III trial of darbepoetin alfa in lung cancer patients receiving chemotherapy.

BACKGROUND: Patients receiving chemotherapy often develop anemia. Darbepoetin alfa (Aranesp(TM)) is an erythropoiesis-stimulating glycoprotein that has been shown, in dose-finding studies, to be safe and clinically active when administered to patients with cancer every 1, 2, or 3 weeks. This phase III study compared the safety and efficacy of darbepoetin alfa with placebo in patients with lung cancer receiving chemotherapy. METHODS: In this multicenter, double-blind, placebo-controlled study, 320 anemic patients (hemoglobin or=25% improvement; mean difference = 13%; 95% CI = 2% to 23%, P =.019) than patients receiving placebo. Patients receiving darbepoetin alfa did not appear to have any untoward effect in disease outcome and did not develop antibodies to the drug. Adverse events were similar between the groups. CONCLUSIONS: Patients with chemotherapy-associated anemia can safely and effectively be treated with weekly darbepoetin alfa therapy. Darbepoetin alfa decreased blood transfusion requirements, increased hemoglobin concentration, and decreased fatigue. Although no conclusions can be drawn about survival from this study, the potential salutary effect on disease outcome warrants further investigation in a prospectively designed study.