Comparison of Bisulfite Pyrosequencing and Methylation-Specific qPCR for Methylation Assessment

Different methodological approaches are available to assess DNA methylation biomarkers. In this study, we evaluated two sodium bisulfite conversion-dependent methods, namely pyrosequencing and methylation-specific qPCR (MS-qPCR), with the aim of measuring the closeness of agreement of methylation values between these two methods and its effect when setting a cut-off. Methylation of tumor suppressor gene p16/INK4A was evaluated in 80 lung cancer patients from which cytological lymph node samples were obtained. Cluster analyses were used to establish methylated and unmethylated groups for each method. Agreement and concordance between pyrosequencing and MS-qPCR was evaluated with Pearson's correlation, Bland-Altman, Cohen's kappa index and ROC curve analyses. Based on these analyses, cut-offs were derived for MS-qPCR. An acceptable correlation (Pearson's R2 = 0.738) was found between pyrosequencing (PYRmean) and MS-qPCR (NMP; normalized methylation percentage), providing similar clinical results when categorizing data as binary using cluster analysis. Compared to pyrosequencing, MS-qPCR tended to underestimate methylation for values between 0 and 15%, while for methylation >30% overestimation was observed. The estimated cut-off for MS-qPCR data based on cluster analysis, kappa-index agreement and ROC curve analysis were much lower than that derived from pyrosequencing. In conclusion, our results indicate that independently of the approach used for estimating the cut-off, the methylation percentage obtained through MS-qPCR is lower than that calculated for pyrosequencing. These differences in data and therefore in the cut-off should be examined when using methylation biomarkers in the clinical practice

Social and clinical predictors of short- and long-term readmission after a severe exacerbation of copd

INTRODUCTION AND OBJECTIVES: The aim of this study was to evaluate the predictive ability of multiple social, and clinical factors for readmission after a severe acute exacerbation of COPD (AECOPD) during various time periods. METHODS: We performed a prospective cohort study in which recruited patients with AECOPD. We systematically collected numerous clinical (symptoms, pulmonary function, comorbidities, and treatment) and social (financial situation, housing situation, family support, caregiver overload, ability to perform activities, and risk of social exclusion) variables using several questionnaires and indices. The patients were followed closely for one year and readmissions at 30, 60, and 365 days were analysed. RESULTS: 253 patients were included, aged 68.9+/-9.8years, FEV1 = 42.1%+/-14.2%, and a Charlson's index = 1.8+/-0.9. Of these patients, 20.2%, 39.6%, and 63.7% were readmitted within the first 30, 90, and 365 days after discharge, respectively. In the multivariate model applied, the variables that were independently associated with readmission over all three periods of the analysis were dependence to perform basic activities of daily living (BADLs) (odds ratio [OR] = 2.10-4.10) and a history of two or more admissions within the previous year (OR = 2.78-3.78). At 90 days, a history of bacterial isolates in a previous sputum culture (OR = 2.39) and at 365 days, a high grade of dyspnoea (OR = 2.51) and obesity (OR = 2.38) were also identified as predictors of hospital readmission. CONCLUSIONS: The patients' limitation to perform BADLs and their history of admissions for AECOPD were the best predictive variables for the likelihood of readmission when adjusted for many other social and clinical variables, regardless of the time period considered for such prediction

Lung emphysema and lung cancer: what do we know about it?

Emphysema and lung cancer (LC) are two diseases which share common risk factors, e.g., smoking. In recent years, many studies have sought to analyse this association. By way of illustration, we conducted a review of the scientific literature of the studies published to date, whose main designated aim was to demonstrate the relationship between emphysema and LC, and this association's influence on the histology, prognosis and molecular mechanisms responsible. We included over 40 studies (ranging from case-control and cohort studies to systematic reviews and meta-analyses), which highlight the association between emphysema and LC, independently of smoking habit. These studies also report a possible influence on histology, with adenocarcinoma being the most frequent lineage, and an association with poor prognosis, which affects both survival and post-operative complications. Oxidative stress, which generates chronic inflammatory status as well as the presence of certain polymorphisms in various genes (CYP1A1, TERT, CLPTM1L, ERK), gives rise-in the case of patients with emphysema-to alteration of cellular repair mechanisms, which in turn favours the proliferation of neoplastic epithelial cells responsible for the origin of LC

Evaluation of Suboptimal Peak Inspiratory Flow in Patients with Stable COPD

OBJECTIVE: Although the importance of assessing inspiratory flow in the selection of treatments for chronic obstructive pulmonary disease (COPD) is understood, evaluation of this factor is not yet widespread or standardized. The objective of the present work was to evaluate the peak inspiratory flow (PIF) of patients with COPD and to explore the variables associated with a suboptimal PIF. METHODS: An observational, cross-sectional study was carried out at specialized nursing consultations over a period of 6 months. We collected clinical data as well as data on symptoms, treatment adherence, and patient satisfaction with their inhalers via questionnaires. PIF was determined using the In-Check Dial G16((R)) device (Clement Clarke International, Ltd., Harlow, UK). In each case, the PIF was considered suboptimal when it was off-target for any of the prescribed inhalers. The association with suboptimal PIF was evaluated using multivariate logistic regression and the results were expressed as the odds ratio (OR) with 95% confidence interval (CI). RESULTS: A total of 122 COPD patients were included in this study, of whom 34 (27.9%) had suboptimal PIF. A total of 229 inhalers were tested, of which 186 (81.2%) were dry powder devices. The multivariate analysis found an association between suboptimal PIF and age (OR = 1.072; 95% CI (1.019, 1.128); p = 0.007) and forced vital capacity (OR = 0.961; 95% CI (0.933, 0.989); p = 0.006). CONCLUSIONS: About a third of patients in complex specialized COPD care have suboptimal PIFs, which is related to age and forced vital capacity

Validation of Calprotectin As a Novel Biomarker For The Diagnosis of Pleural Effusion: a Multicentre Trial

Discriminating between malignant pleural effusion (MPE) and benign pleural effusion (BPE) remains difficult. Thus, novel and efficient biomarkers are required for the diagnosis of pleural effusion (PE). The aim of this study was to validate calprotectin as a diagnostic biomarker of PE in clinical settings. A total of 425 patients were recruited, and the pleural fluid samples collected had BPE in 223 cases (53.7%) or MPE in 137 patients (33%). The samples were all analysed following the same previously validated clinical laboratory protocols and methodology. Calprotectin levels ranged from 772.48 to 3,163.8 ng/mL (median: 1,939 ng/mL) in MPE, and 3,216-24,000 ng/mL in BPE (median: 9,209 ng/mL; p < 0.01), with an area under the curve of 0.848 [95% CI: 0.810-0.886]. For a cut-off value of </= 6,233.2 ng/mL, we found 96% sensitivity and 60% specificity, with a negative and positive predictive value, and negative and positive likelihood ratios of 96%, 57%, 0.06, and 2.4, respectively. Multivariate analysis showed that low calprotectin levels was a better discriminator of PE than any other variable [OR 28.76 (p < 0.0001)]. Our results confirm that calprotectin is a new and useful diagnostic biomarker in patients with PE of uncertain aetiology which has potential applications in clinical practice because it may be a good complement to cytological methods

Polymorphisms in the BER and NER pathways and their influence on survival and toxicity in never-smokers with lung cancer

Polymorphisms in DNA repair pathways may play a relevant role in lung cancer survival in never-smokers. Furthermore, they could be implicated in the response to chemotherapy and toxicity of platinum agents. The aim of this study was to evaluate the influence of various genetic polymorphisms in the BER and NER DNA repair pathways on survival and toxicity in never-smoker LC patients. The study included never-smokers LC cases diagnosed from 2011 through 2019, belonging to the Lung Cancer Research In Never Smokers study. A total of 356 never-smokers cases participated (79% women; 83% adenocarcinoma and 65% stage IV). Survival at 3 and 5 years from diagnosis was not associated with genetic polymorphisms, except in the subgroup of patients who received radiotherapy or chemo-radiotherapy, and presented with ERCC1 rs3212986 polymorphism. There was greater toxicity in those presenting OGG1 rs1052133 (CG) and ERCC1 rs11615 polymorphisms among patients treated with radiotherapy or chemo-radiotherapy, respectively. In general, polymorphisms in the BER and NER pathways do not seem to play a relevant role in survival and response to treatment among never-smoker LC patients

Exposure to Residential Radon and COPD?: A Systematic Review

Introduction: The aim of this study was to analyse the relationship between exposure to residential radon and chronic obstructive pulmonary disease (COPD) by means of a systematic review. Material and Methods: A search was conducted in PubMed and OVID for papers making reference to the radon-COPD relationship. No search filters were applied, whether by date of publication, study type or sample size. All studies not written in English or Spanish were discarded. Results: A total of 174 and 57 papers were found in PubMed and OVID, respectively: of these, 13 (11 on miners and 2 on the general population) fulfilled the inclusion criteria. Only four of the studies on cohorts of miners analysed COPD as a specific disease, and only one reported statistically significant results. In addition, many of these studies lacked information on tobacco use among miners. In contrast, studies conducted on the general public showed an association between mortality and hospital admissions, on the one hand, and residential radon on the other. Conclusion: There are not enough studies to provide a basis for confirming or ruling out an association between radon exposure and COPD. Nonetheless, the most recent general population studies point to evidence of a possible association. In view of the heterogeneity of available studies, it is impossible to say whether this gas may or may not affect COPD morbidity and mortality, until such a time as further studies are carried out