Chengping Hu

Clinical Characteristics of 26 Human Cases of Highly Pathogenic Avian Influenza A (H5N1) Virus Infection in China

Background While human cases of highly pathogenic avian influenza A (H5N1) virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. Methodology/Principal Findings Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6–62) and 58% were female. Many H5N1 cases reported fever (92%) and cough (58%) at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%), cardiac failure (50%), elevated aminotransaminases (43%), and renal dysfunction (17%). Fatal cases had a lower median nadir platelet count (64.5×109 cells/L vs 93.0×109 cells/L, p = 0.02), higher median peak lactic dehydrogenase (LDH) level (1982.5 U/L vs 1230.0 U/L, p = 0.001), higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034) and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011) than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003). Conclusions/Significance The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

Decreased expression of microRNA-375 in nonsmall cell lung cancer and its clinical significance.

Objective: Emerging evidence has shown the association of aberrant microRNA-375 (miR-375) expression with tumourigenesis in many types of human malignancy. This prospective study characterized the contribution of miR-375 to the initiation and progression of nonsmall cell lung cancer (NSCLC). Methods: The real-time reverse transcription-polymerase chain reaction was used to examine miR-375 levels prospectively in 96 pairs of samples of NSCLC tissue and adjacent noncancerous tissue (> 2 cm from cancer tissue). The relationship between miR-375 levels and clinico pathological features was also explored. Results: MiR-375 was downregulated in 89% (85/96) of NSCLC samples compared with matched noncancerous tissue samples. Decreased miR-375 correlated significantly with advanced disease stage and lymphatic metastasis. Univariate and multivariate Cox proportional hazard regression analyses revealed that underexpression of miR-375 was an unfavourable prognostic factor for overall survival in NSCLC. Conclusions: This study suggested that miR-375 is a novel prognostic indicator in NSCLC and might be a potential target for diagnosis and gene therapy.

Activation of Lymphocytes Induced by Bronchial Epithelial Cells with Prolonged RSV Infection

Respiratory syncytial virus (RSV) preferentially infects airway epithelial cells,which might be responsible for susceptibility to asthma; however, the underlying mechanism is not clear. This study determined the activation of lymphocytes and drift of helper T (Th) subsets induced by RSV-infected human bronchial epithelial cells (HBECs) in vitro. HBECs had prolonged infection with RSV, and lymphocytes isolated from human peripheral blood were co-cultured with RSV-infected HBECs. Four groups were established, as follows: lymphocytes (group L); lymphocytes infected with RSV (group RL); co-culture of lymphocytes with non-infected HBECs (group HL); and co-culture of lymphocytes with infected HBECs (group HRL). After co-culture with HBECs for 24 hours, lymphocytes were collected and the following were determined in the 4 groups: cell cycle status; apoptosis rate; and concentrations of IL-4, IFN-γ, and IL-17 in the supernatants. Cell cycle analysis for lymphocytes showed a significant increase in S phase cells, a decrease in G1 phase cells, and a higher apoptosis rate in group HRL compared with the other three groups. In group HRL, the levels of IL-4, IFN-γ, and IL-17 in supernatants were also higher than the other three groups. For further study, lymphocytes were individually treated with supernatants from non-infected and RSV-infected HBECs for 24 h. We showed that supernatants from RSV-infected HBECs induced the differentiation of Th2 and Th17 subsets, and suppressed the differentiation of Treg subsets. Our results showed that HBECs with prolonged RSV infection can induce lymphocyte proliferation and apoptosis, and enhance the release of cytokines by lymphocytes. Moreover, subset drift might be caused by RSV-infected HBECs.

Recent developments in the role of reactive oxygen species in allergic asthma

Allergic asthma has a global prevalence, morbidity, and mortality. Many environmental factors, such as pollutants and allergens, are highly relevant to allergic asthma. The most important pathological symptom of allergic asthma is airway inflammation. Accordingly, the unique role of reactive oxygen species (ROS) had been identified as a main reason for this respiratory inflammation. Many studies have shown that inhalation of different allergens can promote ROS generation. Recent studies have demonstrated that several pro-inflammatory mediators are responsible for the development of allergic asthma. Among these mediators, endogenous or exogenous ROS are responsible for the airway inflammation of allergic asthma. Furthermore, several inflammatory cells induce ROS and allergic asthma development. Airway inflammation, airway hyper-responsiveness, tissue injury, and remodeling can be induced by excessive ROS production in animal models. Based on investigations of allergic asthma and ROS formation mechanisms, we have identified several novel anti-inflammatory therapeutic treatments. This review describes the recent data linking ROS to the pathogenesis of allergic asthma.

Neutrophil extracellular traps are indirectly triggered by lipopolysaccharide and contribute to acute lung injury.

Neutrophil extracellular traps (NETs) facilitate the extracellular killing of pathogens. However, excessive NETs formation and poor degradation are associated with exacerbated immune responses and tissue injury. In this study, we investigated the role of NETs in lipopolysaccharide (LPS)-mediated acute lung injury (ALI) and assessed the use of DNase I, for the treatment of ALI. Additionally, we focused on the controversial issue of whether LPS directly induces NETs release in vitro. NETs formation was detected in murine ALI tissue in vivo and was associated with increased NETs markers, citrullinated-histone H3 tissue levels and NET-DNA levels in BALF. Treatment with DNase I significantly degraded NETs and reduced citrullinated-histone H3 levels, which protected against ALI and ameliorated pulmonary oedema and total protein in BALF. In addition, DNase I significantly reduced IL-6 and TNF-α levels in plasma and BALF. In vitro, LPS-activated platelets rather than LPS alone efficiently induced NETs release. In conclusion, NETs formed during LPS-induced ALI, caused organ damage and initiated the inflammatory response. NETs degradation by DNase I promoted NET-protein clearance and protected against ALI in mice; thus, DNase I may be a new potential adjuvant for ALI therapy. Specifically, LPS induced NETs formation in an indirect manner via platelets activation.

Fluorofenidone attenuates bleomycin-induced pulmonary inflammation and fibrosis in mice via restoring caveolin 1 expression and inhibiting mitogen-activated protein kinase signaling pathway.

Idiopathic pulmonary fibrosis is a progressive, life-threatening, interstitial lung disease with no effective therapy. In this study, we evaluated the effects of fluorofenidone (FD), a novel pyridone agent, on a murine model of bleomycin-induced pulmonary inflammation and fibrosis. Institute for Cancer Research mice were intravenously injected with BLM or saline for 14 consecutive days. Fluorofenidone, pirfenidone (500 mg · kg−1 · d−1, respectively), or vehicle was administered throughout the course of the experiment. Animals were killed on day 28, and various parameters reflecting pulmonary vascular permeability, influx of inflammatory cells, and levels of transforming growth factor &bgr; in the bronchoalveolar lavage fluid were assessed. Collagen I, &agr;-smooth muscle actin, and fibronectin were measured by real-time reverse transcriptase–polymerase chain reaction or Western blot. Furthermore, caveolin 1 and activation of P38, extracellular signal–regulated kinase, and c-Jun N-terminal kinase were detected by Western blot. Fluorofenidone treatment significantly attenuated the increased pulmonary damage index score, the levels of proteins, transforming growth factor &bgr;, and the influx of cells in bronchoalveolar lavage fluid. Fluorofenidone also markedly reduced the expression of fibronectin, &agr;-smooth muscle actin, and collagen I in mouse lung tissues. Inversely, FD restored caveolin 1 protein and mRNA expression, which was significantly downregulated in BLM-induced lung fibrosis. Fluorofenidone also inhibited phosphorylation of extracellular signal–regulated kinase, P38, and c-Jun N-terminal kinase. These findings collectively suggest that FD is an effective agent with antifibrotic and anti-inflammatory properties, and the mechanisms of its antifibrotic effect include regulating caveolin 1 expression and blocking mitogen-activated protein kinase signaling pathways. ABBREVIATIONS &agr;-SMA — &agr;-smooth muscle actin BLM — bleomycin BALF — bronchoalveolar lavage fluid ECM — extracellular matrix FD — fluorofenidone IPF — idiopathic pulmonary fibrosis MAPK — mitogen-activated protein kinase PD — pirfenidone SA — saline TGF-&bgr; — transforming growth factor &bgr;

Rnd3 regulates lung cancer cell proliferation through notch signaling.

Rnd3/RhoE is a small Rho GTPase involved in the regulation of different cell behaviors. Dysregulation of Rnd3 has been linked to tumorigenesis and metastasis. Lung cancers are the leading cause of cancer-related death in the West and around the world. The expression of Rnd3 and its ectopic role in non-small cell lung cancer (NSCLC) remain to be explored. Here, we reported that Rnd3 was down-regulated in three NSCLC cell lines: H358, H520 and A549. The down-regulation of Rnd3 led to hyper-activation of Rho Kinase and Notch signaling. The reintroduction of Rnd3 or selective inhibition of Notch signaling, but not Rho Kinase signaling, blocked the proliferation of H358 and H520 cells. Mechanistically, Notch intracellular domain (NICD) protein abundance in H358 cells was regulated by Rnd3-mediated NICD proteasome degradation. Rnd3 regulated H358 and H520 cell proliferation through a Notch1/NICD/Hes1 signaling axis independent of Rho Kinase.

Overexpression of lncRNA HOXA11-AS promotes cell epithelial–mesenchymal transition by repressing miR-200b in non-small cell lung cancer

BackgroundRecent studies have verified that long noncoding RNAs (lncRNAs) involved in many biological functions and play crucial roles in human cancers progression, the study aimed to detect the association between long non-coding RNA HOXA11-AS and epithelial–mesenchymal transition (EMT) process in non-small cell lung cancer (NSCLC).MethodsThe lncRNA HOXA11-AS expression levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR) assays in 78 paired of tumor tissue and adjacent normal tissue samples in NSCLC patients. Kaplan–Meier survival curves and log-rank test was used to examine the association between lncRNA HOXA11-AS expression and the over survival time in NSCLC patients. Transwell invasion assay was performed to detect the cell invasion ability. QRT-PCR and western-blot analysis detected the mRNA and protein expression of EMT related transcription factors ZEB1/ZEB2, Snail1/2 and EMT marker E-cadherin and N-cadherin in NSCLC cells. RIP and Chromatin immunoprecipitation assays were performed to analyze the association between lncRNA HOXA11-AS and miR-200b expression in NSCLC cells.ResultsThe lncRNA HOXA11-AS expression levels were significantly higher in NSCLC tissues compared with adjacent normal tissues and higher HOXA11-AS expression levels had a poor prognosis in NSCLC patients. Furthermore, knockdown of lncRNA HOXA11-AS in A549 and H1299 cells dramatically inhibited cell invasive abilities. Besides, the transcription levels and protein levels of EMT related transcription factors ZEB1/ZEB2, Snail1/2, and EMT maker N-cadherin were down-regulated after lncRNA HOXA11-AS was knocked down, but the mRNA and protein expression levels of EMT maker E-cadherin was increasing in A549 and H1299 cells. The mechanistic findings showed demonstrated that HOXA11-AS interacted with EZH2 and DNMT1 and recruited them to the miR-200b promoter regions to repress miR-200b expression in NSCLC cells, which promoted cell EMT in NSCLC.ConclusionsOur results showed that up-regulation of lncRNA HOXA11-AS predicted a poor prognosis and lncRNA HOXA11-AS promoted cell epithelial–mesenchymal transition (EMT) by inhibiting miR-200b expression in NSCLC.

Etiologic Diagnosis of Lower Respiratory Tract Bacterial Infections Using Sputum Samples and Quantitative Loop-Mediated Isothermal Amplification

Etiologic diagnoses of lower respiratory tract infections (LRTI) have been relying primarily on bacterial cultures that often fail to return useful results in time. Although DNA-based assays are more sensitive than bacterial cultures in detecting pathogens, the molecular results are often inconsistent and challenged by doubts on false positives, such as those due to system- and environment-derived contaminations. Here we report a nationwide cohort study on 2986 suspected LRTI patients across P. R. China. We compared the performance of a DNA-based assay qLAMP (quantitative Loop-mediated isothermal AMPlification) with that of standard bacterial cultures in detecting a panel of eight common respiratory bacterial pathogens from sputum samples. Our qLAMP assay detects the panel of pathogens in 1047(69.28%) patients from 1533 qualified patients at the end. We found that the bacterial titer quantified based on qLAMP is a predictor of probability that the bacterium in the sample can be detected in culture assay. The relatedness of the two assays fits a logistic regression curve. We used a piecewise linear function to define breakpoints where latent pathogen abruptly change its competitive relationship with others in the panel. These breakpoints, where pathogens start to propagate abnormally, are used as cutoffs to eliminate the influence of contaminations from normal flora. With help of the cutoffs derived from statistical analysis, we are able to identify causative pathogens in 750 (48.92%) patients from qualified patients. In conclusion, qLAMP is a reliable method in quantifying bacterial titer. Despite the fact that there are always latent bacteria contaminated in sputum samples, we can identify causative pathogens based on cutoffs derived from statistical analysis of competitive relationship. Trial Registration ClinicalTrials.gov NCT00567827

EGCG induces lung cancer A549 cell apoptosis by regulating Ku70 acetylation

Lung cancer is the leading cause of cancer-related death worldwide. (-)-Epigallocatechin-3-gallate (EGCG) is a potential chemopreventive and therapeutic agent for lung cancer. Induction of apoptosis was examined using Annexin V/PI double staining flow cytometry. Western blot analysis detected the protein expression of cleaved caspase-3, Bax and Bcl-xL. Co-immunoprecipitation was used to detect the interaction of Ku70-Bax and the acetylation status of Ku70. Treatment of A549 cells with EGCG-induced apoptosis via increased expression of cleaved caspase-3 and Bax, but decreased expression of Bcl-xL. EGCG upregulated the K70 acetylation status of A549 cells and downregulated the interaction of Bax-Ku70 in a concentration- and time-dependent manner. The apoptosis-promoting effect of EGCG on A549 cells was obviously weakened, along with strengthening of the Bax-Ku70 interaction, after pCDNA3.1(+)-Ku70 plasmid and pCDNA3.1(+)-Ku70539/542R plasmid transfection. Our results established a role of EGCG in inducing cell apoptosis by suppressing Bax activity. Regulating Ku70 acetylation by EGCG, that block the interaction between Ku70 and Bax, will result in lung cancer cell apoptosis.