Inferior Vena Cava Filters: Adherence to Clinical Practice Guidelines Recommendations, Retrieval Rates, and Filter Complications in a Tertiary Hospital.

The present study evaluated the adherence to guideline recommendations regarding the indication for inferior vena cava filter (IVCF) placement, retrieval rates, complications, thrombotic recurrences, and mortality. Patients in whom an IVCF was placed between 2015 and 2020 in a tertiary hospital were retrospectively included. We considered absolute indication of IVCF placement if all the guidelines evaluated agreed on the indication, relative indication if only some guidelines recommended it and without indication if none of the evaluated guidelines recommended it. From the 185 patients included; 47% had an absolute indication, 15% a relative indication, and 38% had no indication. Filter-associated complications and non-removal rates were 12.4% and 41%, respectively. Venous thromboembolism recurrence rate was 17.8%, being filter-associated complications (24.2 vs 9.8%, P = .02) and thrombosis of the inferior cava or iliac veins (12.1 vs 2.6%, P = .03) more frequent in this group. The mortality rate was 40%, with higher mortality risk in patients with co-existing cancer. Previous major bleeding, filter-associated complications, and mortality were associated with a major risk of non-removal. In conclusion, the adherence to guidelines regarding the indication of IVCF placement is still low and IVCF complications are not negligible. This fact is of special concern in the elderly, comorbid, and cancer patients.

EBUS-TBNA in Extrathoracic Malignancies: Diagnostic and Prognostic Implications.

PURPOSE: In patients with extrathoracic malignancies (EM) the role of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the assessment of abnormal mediastinal lymph nodes (MLN) is controversial. The aim of this study was to assess the diagnostic yield and prognostic significance of EBUS-TBNA in these patients. METHODS: Retrospective analysis of patients with EM and abnormal MLN detected by Computed Tomography (CT) and/or Positron Emission Tomography (PET). RESULTS: A total of 161 patients with EM and abnormal MLN were included (93 males, 58%). The most common EM was melanoma (19%) and gastrointestinal cancer (17%). Assessed lymph nodes were mediastinal in 70% of cases and hilar in 30%. The most frequently sampled lymph nodes were subcarinal (45%) and lower right paratracheal (21%). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of EBUS-TBNA for the diagnosis of malignancy were 88%, 100%, 100% and 87%, respectively. These values were similar regardless the type of EM except for head and neck tumors where the NPV was particularly low (67%). The diagnosis of neoplastic involvement by EBUS-TBNA implied a worse prognosis in terms of overall survival (p < 0.02) and cancer-specific survival (p < 0.001). CONCLUSIONS: In patients with EM and abnormal MLN, EBUS-TBNA has a high diagnostic yield. However, the NPV decrease in patients with head and neck tumors. Neoplastic MLN detected by EBUS-TBNA has prognostic implications in these patients.

Characterization of the MicroRNA Cargo of Extracellular Vesicles Isolated from a Pulmonary Tumor-Draining Vein Identifies miR-203a-3p as a Relapse Biomarker for Resected Non-Small Cell Lung Cancer.

In resected non-small cell lung cancer (NSCLC), post-surgical recurrence occurs in around 40% of patients, highlighting the necessity to identify relapse biomarkers. An analysis of the extracellular vesicle (EV) cargo from a pulmonary tumor-draining vein (TDV) can grant biomarker identification. We studied the pulmonary TDV EV-miRNAome to identify relapse biomarkers in a two-phase study (screening and validation). In the screening phase, a 17-miRNA relapse signature was identified in 18 selected patients by small RNAseq. The most expressed miRNA from the signature (EV-miR-203a-3p) was chosen for further validation. Pulmonary TDV EV-miR-203a-3p was studied by qRT-PCR in a validation cohort of 70 patients, where it was found to be upregulated in relapsed patients (p = 0.0194) and in patients with cancer spread to nearby lymph nodes (N+ patients) (p = 0.0396). The ROC curve analysis showed that TDV EV-miR-203a-3p was able to predict relapses with a sensitivity of 88% (AUC: 0.67; p = 0.022). Moreover, patients with high TDV EV-miR-203a-3p had a shorter time to relapse than patients with low levels (43.6 vs. 97.6 months; p = 0.00703). The multivariate analysis showed that EV-miR-203a-3p was an independent, predictive and prognostic post-surgical relapse biomarker. In conclusion, pulmonary TDV EV-miR-203a-3p is a promising new relapse biomarker for resected NSCLC patients.

Elevated plasma levels of epithelial and endothelial cell markers in COVID-19 survivors with reduced lung diffusing capacity six months after hospital discharge.

BACKGROUND: Some COVID-19 survivors present lung function abnormalities during follow-up, particularly reduced carbon monoxide lung diffusing capacity (DLCO). To investigate risk factors and underlying pathophysiology, we compared the clinical characteristics and levels of circulating pulmonary epithelial and endothelial markers in COVID-19 survivors with normal or reduced DLCO 6 months after discharge. METHODS: Prospective, observational study. Clinical characteristics during hospitalization, and spirometry, DLCO and plasma levels of epithelial (surfactant protein (SP) A (SP-A), SP-D, Club cell secretory protein-16 (CC16) and secretory leukocyte protease inhibitor (SLPI)), and endothelial (soluble intercellular adhesion molecule 1 (sICAM-1), soluble E-selectin and Angiopoietin-2) 6 months after hospital discharge were determined in 215 COVID-19 survivors. RESULTS: DLCO was < 80% ref. in 125 (58%) of patients, who were older, more frequently smokers, had hypertension, suffered more severe COVID-19 during hospitalization and refer persistent dyspnoea 6 months after discharge. Multivariate regression analysis showed that age ≥ 60 years and severity score of the acute episode ≥ 6 were independent risk factors of reduced DLCO 6 months after discharge. Levels of epithelial (SP-A, SP-D and SLPI) and endothelial (sICAM-1 and angiopoietin-2) markers were higher in patients with reduced DLCO, particularly in those with DLCO ≤ 50% ref. Circulating SP-A levels were associated with the occurrence of acute respiratory distress syndrome (ARDS), organizing pneumonia and pulmonary embolisms during hospitalization. CONCLUSIONS: Reduced DLCO is common in COVID-19 survivors 6 months after hospital discharge, especially in those older than 60 years with very severe acute disease. In these individuals, elevated levels of epithelial and endothelial markers suggest persistent lung damage.

Monitoring HOTTIP levels on extracellular vesicles for predicting recurrence in surgical non-small cell lung cancer patients.

In resected non-small cell lung cancer (NSCLC), postsurgical recurrence is the major factor affecting long-term survival. The identification of biomarkers in extracellular vesicles (EV) obtained from serial blood samples after surgery could enhance early detection of relapse and improve NSCLC outcome. Since EV cargo contains long non-coding RNAs (lncRNAs), we aimed to analyze whether the oncogenic lncRNA HOTTIP, which higher expression in tumor tissue was related to worse outcome in NSCLC, could be detected in EV from NSCLC patients and serve as recurrence biomarker. After purification of EVs by ultracentrifugation in 52 serial samples from 18 NSCLC patients, RNA was isolated and HOTTIP was quantified by Real time PCR. We observed that patients that relapsed after surgery displayed increased postsurgical EV HOTTIP levels in comparison with presurgical levels. In the relapsed patients with several samples available between surgery and relapse, we observed an increment in the EV HOTTIP levels when approaching to relapse, which indicated its potential utility for monitoring disease recurrence. When we focused in EV HOTTIP levels in the first post-surgical sample, we observed that the detection of an increment of the expression levels in comparison to presurgical sample, predicted recurrence with high sensitivity (85.7%) and specificity (90.9%) and that patients had shorter time to relapse and shorter overall survival. In conclusion, our pilot study showed that EV HOTTIP is a potential biomarker for monitoring disease recurrence after surgery in NSCLC.

Role of the epithelial-mesenchymal transition-related circular RNA, circ-10720, in non-small-cell lung cancer.

BACKGROUND: Circular RNAs (circRNAs) are non-coding RNAs with a circular structure that have recently emerged as important regulators of tumorogenesis. Recently, several circRNAS, including circ-10720 have been related to epithelial-mesenchymal transition (EMT) process. In the present study, we have analyzed the role of circ-10720 in non-small-cell lung cancer (NSCLC) and studied its prognostic relevance in resected stage I-IIIa NSCLC patients. METHODS: Circ-10720 expression was analyzed using a custom TaqMan assay in four NSCLC cell lines (HCC44, A549, H23 and H1299) and in the normal immortalized lung cell line BEAS2B. Silencing of circ-10720 was performed using two custom siRNAs which were transfected using lipofectamine 2000. Protein levels were evaluated by Western blot and immunofluorescence. Wound healing and invasion assays were performed to evaluate the impact the circRNA on cell motility. Apoptosis was analyzed by evaluation of Caspase 3-7 activity and proliferation by MTS assay. Moreover, the expression levels of the circRNA were studied in 119 resected NSCLC patients. The expression in tumor tissue was correlated with the main clinicopathological characteristics and with time to relapse (TTR). RESULTS: Circ-10720 was overexpressed in HCC44 and A549 and underexpressed in H23 and H1299 NSCLC cell lines in comparison to BEAS2B normal immortalized lung cell line. CircRNA knockdown in the two circ-10720 overexpressing cell lines was associated with a decrease of Vimentin (VIM) and an increase of E-cadherin (CDH1) protein levels, loss of mesenchymal phenotype, and a significant reduction of migration and invasion capacity. After silencing circ-10720, the apoptosis rate increased and the proliferation was significantly reduced. Furthermore, circ-10720 was upregulated in tumor vs. normal tissue from 119 resected NSCLC patients. In the group of patients not receiving adjuvant treatment, those with high levels of circ-10720 had a shorter TTR than those with low levels and emerged as an independent prognostic value in the multivariate analysis. In tumor tissue, circ-10720 levels positively correlated with the EMT gene Twist1 levels. CONCLUSIONS: Circ-10720 regulates EMT, apoptosis and proliferation and acts as a biomarker of relapse in NSCLC.

Multimodal prehabilitation as strategy for reduction of postoperative complications after cardiac surgery: a randomised controlled trial protocol.

INTRODUCTION: Prehabilitation programmes that combine exercise training, nutritional support and emotional reinforcement (multimodal prehabilitation) have demonstrated efficacy reducing postoperative complications in the context of abdominal surgery. However, such programmes have seldom been studied in cardiac surgery, one of the surgeries associated with higher postoperative morbidity and mortality. This trial will assess the feasibility and efficacy in terms of reduction of postoperative complications and cost-effectiveness of a multimodal prehabilitation programme comparing to the standard of care in cardiac surgical patients. METHODS AND ANALYSIS: This is a single-centre, randomised, open-label, controlled trial with a 1:1 ratio. Consecutive 160 elective valve replacement and/or coronary revascularisation surgical patients will be randomised to either standard of care or 4-6 weeks of multimodal prehabilitation that will consist in (1) two times/week supervised endurance and strength exercise training sessions, (2) promotion of physical activity and healthy lifestyle, (3) respiratory physiotherapy, (4) nutrition counselling and supplementation if needed, and (5) weekly mindfulness sessions. Baseline, preoperative and 3-month postoperative data will be collected by an independent blinded evaluator. The primary outcome of this study will be the incidence of postoperative complications. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee of Clinical investigation of Hospital Clinic de Barcelona (HCB/2017/0708). The results will be disseminated in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03466606.

Association Between Systemic and Pulmonary Vascular Dysfunction in COPD.

Introduction: In chronic obstructive pulmonary disease (COPD), endothelial dysfunction and stiffness of systemic arteries may contribute to increased cardiovascular risk. Pulmonary vascular disease (PVD) is frequent in COPD. The association between PVD and systemic vascular dysfunction has not been thoroughly evaluated in COPD. Methods: A total of 108 subjects were allocated into four groups (non-smoking controls, smoking controls, COPD without PVD and COPD with PVD). In systemic arteries, endothelial dysfunction was assessed by flow-mediated dilation (FMD) and arterial stiffness by pulse wave analysis (PWA) and pulse wave velocity (PWV). PVD was defined by a mean pulmonary artery pressure (PAP) ≥25 mmHg at right heart catheterization or by a tricuspid regurgitation velocity >2.8 m/s at doppler echocardiography. Biomarkers of inflammation and endothelial damage were assessed in peripheral blood. Results: FMD was lower in COPD patients, with or without PVD, compared to non-smoking controls; and in patients with COPD and PVD compared to smoking controls. PWV was higher in COPD with PVD patients compared to both non-smoking and smoking controls in a model adjusted by age and the Framingham score; PWV was also higher in patients with COPD and PVD compared to COPD without PVD patients in the non-adjusted analysis. FMD and PWV correlated significantly with forced expiratory volume in the first second (FEV1), diffusing capacity for carbon monoxide (DLCO) and systolic PAP. FMD and PWV were correlated in all subjects. Discussion: We conclude that endothelial dysfunction of systemic arteries is common in COPD, irrespective if they have PVD or not. COPD patients with PVD show increased stiffness and greater impairment of endothelial function in systemic arteries. These findings suggest the association of vascular impairment in both pulmonary and systemic territories in a subset of COPD patients.

Extracellular Vesicle lincRNA-p21 Expression in Tumor-Draining Pulmonary Vein Defines Prognosis in NSCLC and Modulates Endothelial Cell Behavior.

Hypoxia-induced upregulation of lincRNA-p21 in tumor tissue was previously shown by our group to be related to poor prognosis in resected non-small cell lung cancer (NSCLC) patients. In the present study, we have evaluated the presence of lincRNA-p21 in extracellular vesicles (EVs) from NSCLC patients and assessed its potential as a prognostic biomarker. High EV lincRNA-p21 levels in blood from the tumor-draining vein were associated with shorter time to relapse and shorter overall survival. Moreover, the multivariate analysis identified high lincRNA-p21 levels as an independent prognostic marker. In addition, lincRNA-p21 was overexpressed in H23 and HCC44 NSCLC cell lines and their derived EVs under hypoxic conditions. Functional assays using human umbilical vein endothelial cells (HUVECs) showed that tumor-derived EVs enriched in lincRNA-p21 affected endothelial cells by promoting tube formation and enhancing tumor cell adhesion to endothelial cells. Additionally, the analysis of selected EV microRNAs related to angiogenesis and metastasis showed that the microRNAs correlated with EV lincRNA-p21 levels in both patients and cell lines. Finally, EV co-culture with HUVEC cells increased the expression of microRNAs and genes related to endothelial cell activation. In conclusion, EV lincRNA-p21 acts as a novel prognosis marker in resected NSCLC patients, promoting angiogenesis and metastasis.

Long Non-Coding RNA NANCI/NKX2-1 Duplex Impacts Prognosis in Stage I Non-Small-Cell Lung Cancer.

BACKGROUND: NANCI, an intergenic long non-coding RNA (lncRNA) is essential for buffering NKX2-1 expression during embryonic development and in adult tissue. We analyzed NANCI and NKX2-1 in human lung embryonic samples and adult lung tissues and evaluated their potential as prognostic markers in stage I non-small cell lung cancer (NSCLC). METHODS AND RESULTS: NANCI and NKX2-1 expression was assessed by TaqMan assays in 18 human embryonic samples from 8 to 13 weeks, 59 non-tumoral (NT) lung tissue samples, and 98 stage I NSCLC tumor samples. NANCI and NKX2-1 expression in embryonic and NSCLC samples were downregulated in comparison to adult NT tissue. Patients with low expression of NANCI had shorter disease-free survival (DFS) and overall survival (OS) than those with high levels (47.6 vs 69.3 months, P=0.032 and 57.7 vs 77.6 months, P=0.021, respectively). When the expression levels of NANCI and NKX2-1 were evaluated in combination, four groups were identified (high NANCI/high NKX2-1, low NANCI/high NKX2-1, high NANCI/low NKX2-1 and low NANCI/low NKX2-1) with differential impact on DFS (P=0.042) and OS (P=0.024). Interestingly, the high NANCI/high NKX2-1 duplex group had longer DFS and OS than the other three groups (71.25 vs 46.3 months, P=0.009 and 81.3 vs 56.1 months, P=0.004, respectively). In the multivariate analysis, the high NANCI/high NKX2-1 duplex was identified as an independent prognostic factor for longer DFS (HR 0.346, 95% CI, 0.169-0.709; P=0.004) and OS (HR 0.309, 95% CI, 0.121-0.786; P=0.014). CONCLUSIONS: NANCI and the NANCI-NKX2-1 duplex impacts prognosis in stage I NSCLC patients.

Acute exacerbations of idiopathic pulmonary fibrosis: Does clinical stratification or steroid treatment matter?

Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) is defined as a sudden acceleration of the disease with the appearance of pulmonary infiltrates superimposed on the characteristic pattern of IPF that leads to a significant decline in lung function. It has high in-hospital mortality rates, despite medical treatment with systematic steroids. We sought to investigate whether there were in-hospital mortality differences according to clinical stratification (AE, suspected AE, or AE of known cause) and/or treatment with systemic steroids. We reviewed the clinical characteristics and outcomes of patients with IPF admitted to our hospital during the years 2003-2014 due to a worsening of their clinical status. We identified 50 IPF patients, 9 with AE (18%), 12 with suspected exacerbation (24%), and 29 with AE of known cause (58%), mostly respiratory infections. In-hospital mortality was similar in the three groups (33% vs. 17% vs. 34%, respectively). Likewise, we did not find differences between them with respect to the use of systemic steroids (length of treatment duration or total dose). Nevertheless, there was an independent association between in-hospital mortality and high average daily steroid dose. We did not observe significant differences in prognosis or use of systemic steroids according to current diagnostic stratification groups in patients hospitalized because of an exacerbation of IPF.

Clinical significance of long non-coding RNA HOTTIP in early-stage non-small-cell lung cancer.

BACKGROUND: HOTTIP, a long non-coding RNA located in the HOXA cluster, plays a role in the patterning of tissues with mesodermal components, including the lung. Overexpression of HOXA genes, including HOTTIP, has been associated with a more aggressive phenotype in several cancers. However, the prognostic impact of HOTTIP has not yet been explored in non-small-cell lung cancer (NSCLC). We have correlated HOTTIP expression with time to relapse (TTR) and overall survival (OS) in early-stage NSCLC patients. METHODS: Ninety-nine early-stage NSCLC patients who underwent surgical resection in our center from June 2007 to November 2013 were included in the study. Mean age was 66; 77.8% were males; 73.7% had stage I disease; and 55.5% had adenocarcinoma. A validation data set comprised stage I-II patients from The Cancer Genome Atlas (TCGA) Research Network. RESULTS: HOTTIP was expressed in all tumor samples and was overexpressed in squamous cell carcinoma (p = 0.007) and in smokers (p = 0.018). Patients with high levels of HOTTIP had shorter TTR (78.3 vs 58 months; p = 0.048) and shorter OS (81.2 vs 61 months; p = 0.023) than those with low levels. In the multivariate analysis, HOTTIP emerged as an independent prognostic marker for TTR (OR: 2.05, 95%CI: 1-4.2; p = 0.05), and for OS (OR: 2.31, 95%CI: 1.04-5.1; p = 0.04). HOTTIP was validated as a prognostic marker for OS in the TCGA adenocarcinoma cohort (p = 0.025). Moreover, we identified a 1203-mRNA and a 61-miRNA signature that correlated with HOTTIP expression. CONCLUSIONS: The lncRNA HOTTIP can be considered a prognostic biomarker in early-stage NSCLC.

Exosome Analysis in Tumor-Draining Pulmonary Vein Identifies NSCLC Patients with Higher Risk of Relapse after Curative Surgery.

Since tumor-draining pulmonary vein blood (PV) is enriched in tumor-secreted products, we hypothesized that it would also be enriched in tumor-derived exosomes, which would be important in the metastasis process. We characterized exosomes from PV of 61 resected non-small cell lung cancer (NSCLC) patients to evaluate its potential as relapse biomarkers. Exosomes were characterized using transmission electron microscopy, western blot and nanoparticle tracking analysis and we examined time to relapse (TTR) and overall survival (OS). Differences between PV and peripheral vein were found. PV was enriched in smaller exosomes than the paired peripheral vein (p = 0.01). Moreover, PV exosome size mode was able to identify relapsed patients (Area under the curve [AUC] = 0.781; 95%CI: 0.6641⁻0.8978), in whom exosome size was smaller (<112 nm; p < 0.001). The combination of PV exosome size and N (lymph node involvement) showed an AUC of 0.89 (95%CI: 0.80⁻0.97). Moreover, smaller PV exosome size was associated with shorter TTR (28.3 months vs. not reached, p < 0.001) and OS (43.9 months vs. not reached, p = 0.009). Multivariate analyses identified PV exosome size and stage as independent prognostic markers for TTR and OS. PV exosome size is a promising relapse biomarker after surgery that can add valuable information to clinical variables.

Prehabilitation in thoracic surgery.

Surgical resection remains the best treatment option for patients with early stage of non-small cell lung cancer (NSCLC). However, it may be responsible of postoperative complication and mortality, especially in patients with impaired pulmonary function. Enhanced recovery after surgery (ERAS) programs have been focused mainly in minimal invasive surgery approach during lung resection and respiratory rehabilitation after surgery. Preoperative exercise-based intervention (prehabilitation) has demonstrated reduction of morbi-mortality in other surgeries but in thoracic surgery continues to be under discussion. Cardio-pulmonary exercise test (CPET) is the gold standard technique to predict postoperative morbi-mortality. The implementation of a preoperative respiratory rehabilitation could optimize patient's physical capacity before surgery and improve outcomes and enhance recovery. The aim of this systematic review of the literature is to identify the effectiveness and safety of prehabilitation programs in thoracic surgery, the type of exercise and its duration, and the group of patients with best benefit. Prehabilitation is a safe intervention without side effects in patients. High-intensity interval training (HIT) with duration of 2 to 6 weeks seems to be the best exercise programme in a prehabilitation intervention but it exists heterogeneity in terms of intensity and duration. Prehabilitation increase exercise capacity and significantly enhances pulmonary function. But the reduction of postoperative complication and mortality has not been clearly demonstrated. Different criteria selection, type of intervention and small sample size, in addition to no randomization, could justify disparate results. It seems that not all patients can benefit from prehabilitation and it could be indicated only in patients with impaired lung function. Further randomized clinical trials with enough patients, correct duration of HIT (2 to 6 weeks) and focused in COPD patients are needed to clarify the suitability of prehabilitation. Meanwhile, safety of prehabilitation and good results of some studies support this intervention in high-risk patients.

Immunotherapy: a new standard of care in thoracic malignancies? A summary of the European Respiratory Society research seminar of the Thoracic Oncology Assembly.

In May 2017, the second European Respiratory Society research seminar of the Thoracic Oncology Assembly entitled "Immunotherapy, a new standard of care in thoracic malignancies?" was held in Paris, France. This seminar provided an opportunity to review the basis of antitumour immunity and to explain how immune checkpoint inhibitors (ICIs) work. The main therapeutic trials that have resulted in marketing authorisations for use of ICIs in lung cancer were reported. A particular focus was on the toxicity of these new molecules in relation to their immune-related adverse events. The need for biological selection, currently based on immunohistochemistry testing to identify the tumour expression of programmed death ligand (PD-L)1, was stressed, as well as the need to harmonise PD-L1 testing and techniques. Finally, sessions were dedicated to the combination of ICIs and radiotherapy and the place of ICIs in nonsmall cell lung cancer with oncogenic addictions. Finally, an important presentation was dedicated to the future of antitumour vaccination and of all ongoing trials in thoracic oncology.

NKX2-1 expression as a prognostic marker in early-stage non-small-cell lung cancer.

BACKGROUND: NKX2-1, a key molecule in lung development, is highly expressed in non-small cell lung cancer (NSCLC), particularly in lung adenocarcinoma (ADK), where it is a diagnostic marker. Studies of the prognostic role of NKX2-1 in NSCLC have reported contradictory findings. Two microRNAs (miRNAs) have been associated with NKX2-1: miR-365, which targets NKX2-1; and miR-33a, which is downstream of NKX2-1. We have examined the effect of NKX2-1, miR-365 and miR-33a on survival in a cohort of early-stage NSCLC patients and in sub-groups of patients classified according to the mutational status of TP53, KRAS, and EGFR. METHODS: mRNA and miRNA expression was determined using TaqMan assays in 110 early-stage NSCLC patients. TP53, KRAS, and EGFR mutations were assessed by Sanger sequencing. RESULTS: NKX2-1 expression was upregulated in never-smokers (P = 0.017), ADK (P < 0.0001) and patients with wild-type TP53 (P = 0.001). A negative correlation between NKX2-1 and miR-365 expression was found (ρ = -0.287; P = 0.003) but there was no correlation between NKX2-1 and miR-33a expression. Overall survival (OS) was longer in patients with high expression of NKX2-1 than in those with low expression (80.8 vs 61.2 months (P = 0.035), while a trend towards longer OS was observed in patients with low miR-365 levels (P = 0.07). The impact of NKX2-1 on OS and DFS was higher in patients with neither TP53 nor KRAS mutations. Higher expression of NKX2-1 was related to higher OS (77.6 vs 54 months; P = 0.017) and DFS (74.6 vs 57.7 months; P = 0.006) compared to low expression. The association between NKX2-1 and OS and DFS was strengthened when the analysis was limited to patients with stage I disease (P = 0.005 and P=0.003 respectively). CONCLUSIONS: NKX2-1 expression impacts prognosis in early-stage NSCLC patients, particularly in those with neither TP53 nor KRAS mutations.

LincRNA-p21 Impacts Prognosis in Resected Non-Small Cell Lung Cancer Patients through Angiogenesis Regulation.

INTRODUCTION: Long intergenic noncoding RNA-p21 (lincRNA-p21) is a long noncoding RNA transcriptionally activated by tumor protein p53 (TP53) and hypoxia inducible factor 1 alpha subunit (HIF1A). It is involved in the regulation of TP53-dependent apoptosis and the Warburg effect. We have investigated the role of lincRNA-p21 in NSCLC. METHODS: LincRNA-p21 expression was assessed in tumor and normal tissue from 128 patients with NSCLC and correlated with time to relapse and cancer-specific survival (CSS). H23, H1299, and HCC-44 cell lines were cultured in hypoxic conditions after silencing of lincRNA-p21. The TaqMan human angiogenesis array was used to explore angiogenesis-related gene expression. Levels of the protein vascular endothelial growth factor A were measured by enzyme-linked immunosorbent assay in the cell supernatants. Angiogenic capability was measured by human umbilical vein endothelial cell tube formation assay. Microvascular density in tumor samples was analyzed by immunohistochemistry. RESULTS: LincRNA-p21 was down-regulated in tumor tissue, but no association was observed with TP53 mutational status. High lincRNA-p21 levels were associated with poor CSS in all patients (p = 0.032). When patients were classified according to histological subtypes, the impact of lincRNA-p21 was confined to patients with adenocarcinoma in both time to relapse (p = 0.006) and CSS (p < 0.001). To explain the poor outcome of patients with high lincRNA-p21 expression, we studied the role of lincRNA-p21 in angiogenesis in vitro and observed a global downregulation in the expression of angiogenesis-related genes when lincRNA-p21 was inhibited. Moreover, supernatants from lincRNA-p21-inhibited cells were significantly less angiogenic and had lower levels of secreted vascular endothelial growth factor A than controls did. Finally, tumor samples with high lincRNA-p21 levels had higher microvascular density. CONCLUSIONS: Our findings suggest that lincRNA-p21 affects outcome in patients with NSCLC adenocarcinoma through the regulation of angiogenesis.

The significance of PIWI family expression in human lung embryogenesis and non-small cell lung cancer.

The expression of Piwi-interacting RNAs, small RNAs that bind to PIWI proteins, was until recently believed to be limited to germinal stem cells. We have studied the expression of PIWI genes during human lung embryogenesis and in paired tumor and normal tissue prospectively collected from 71 resected non-small-cell lung cancer patients. The mRNA expression analysis showed that PIWIL1 was highly expressed in 7-week embryos and downregulated during the subsequent weeks of development. PIWIL1 was expressed in 11 of the tumor samples but in none of the normal tissue samples. These results were validated by immunohistochemistry, showing faint cytoplasmic reactivity in the PIWIL1-positive samples. Interestingly, the patients expressing PIWIL1 had a shorter time to relapse (TTR) (p = 0.006) and overall survival (OS) (p = 0.0076) than those without PIWIL1 expression. PIWIL2 and 4 were downregulated in tumor tissue in comparison to the normal tissue (p < 0.001) and the patients with lower levels of PIWIL4 had shorter TTR (p = 0.048) and OS (p = 0.033). In the multivariate analysis, PIWIL1 expression emerged as an independent prognostic marker. Using 5-Aza-dC treatment and bisulfite sequencing, we observed that PIWIL1 expression could be regulated in part by methylation. Finally, an in silico study identified a stem-cell expression signature associated with PIWIL1 expression.