Enqing Fu

Severe Complications of Bronchoscopy

Background: Interventional bronchoscopy is widely used for the diagnosis and therapy of many lung and airway diseases. Concern has been raised about its complications. Objective: To review the severe complications associated with bronchoscopy. Methods: A retrospective review of clinical records of 23,862 patients who underwent bronchoscopic examination or therapy from December 1983 to December 2004 in our department. Severe complications associated with bronchoscopic examination or therapy were analyzed. Results: During the study period, among 23,862 cases, 152 cases experienced severe complications; 3 cases died; the rate of severe complications was 0.637%; mortality rate was 0.013%. The complications included laryngeal, tracheal and bronchial spasm in 68 cases, hematorrhea in 37 cases, arrhythmia in 19 cases, airway obstruction in 8 cases, esophagotracheal fistula in 5 cases, pneumothorax in 4 cases, tracheal perforation in 3 cases, death in 3 cases. Conclusions: Bronchoscopy is a safe procedure. The increased rate of severe complications and death associated with bronchoscopy may be ascribed to the increasingly wide use of bronchoscopy.

Overexpression of STAT3 Potentiates Growth, Survival, and Radioresistance of Non-Small-Cell Lung Cancer (NSCLC) cells

OBJECTIVE Activation of signal transducer and activator of transcription 3 (STAT3) play important roles in tumorigenesis and tumor progression. The overexpression of STAT3 has been found in various malignancies including non-small-cell lung carcinoma (NSCLC). The purpose of this study was to explore the correlation between overexpression of STAT3 gene and growth, survival, and radiosensitivity of NSCLC cells. METHODS Subclones using vector-based short hairpin RNA (shRNA) were established. RT-PCR and Western blot assays were performed to detect the expression of STAT3 mRNA and protein in untransfected or stably transfected NSCLC cells. Then, MTT and soft agar colony assays were performed to determine the effect of STAT3 inhibition on in vitro growth of NSCLC cells. Hoechst staining assay was performed to analyze the effect of STAT3 inhibition on apoptosis of NSCLC cells. Additionally, clonogenic survival assays were performed to detect the effect of STAT3 inhibition on in vitro radiosensitivity of NSCLC cells. Finally, to examine the effect of pSUPER-shSTAT3 on proliferation and radiosensitivity in vivo, a subcutaneous (s.c.) tumor formation assay in nude mice was performed. RESULTS We successfully established two stable transfected cell lines (A549/shSTAT3 and SK-MES-1/shSTAT3) in which the expression of STAT3 mRNA and protein was down-regulated. Those two stable subclones showed a significantly dramatic reduction in colony-forming ability and proliferation not only in vitro but also in vivo. The apoptotic rates of A549/shSTAT3 and SK-MES-1/shSTAT3 cells increased to 19.2% and 16.4%, respectively. Moreover, shRNA-mediated STAT3 inhibition could also significantly enhance radiosensitivity of NSCLC cells both in vitro and in vivo. CONCLUSION Together, the overexpression of STAT3 is correlated with growth, survival, and radioresistance of NSCLC cells, and STAT3 might be a molecular therapeutic target for gene therapy or radiosensitization of NSCLC.

Epigallocatechin-3-gallate ameliorates seawater aspiration-induced acute lung injury via regulating inflammatory cytokines and inhibiting JAK/STAT1 pathway in rats.

Signal transducers and activators of transcriptions 1 (STAT1) play an important role in the inflammation process of acute lung injury (ALI). Epigallocatechin-3-gallate (EGCG) exhibits a specific and strong anti-STAT1 activity. Therefore, our study is to explore whether EGCG pretreatment can ameliorate seawater aspiration-induced ALI and its possible mechanisms. We detected the arterial partial pressure of oxygen, lung wet/dry weight ratios, protein content in bronchoalveolar lavage fluid, and the histopathologic and ultrastructure staining of the lung. The levels of IL-1, TNF-α, and IL-10 and the total and the phosphorylated protein level of STAT1, JAK1, and JAK2 were assessed in vitro and in vivo. The results showed that EGCG pretreatment significantly improved hypoxemia and histopathologic changes, alleviated pulmonary edema and lung vascular leak, reduced the production of TNF-α and IL-1, and increased the production of IL-10 in seawater aspiration-induced ALI rats. EGCG also prevented the seawater aspiration-induced increase of TNF-α and IL-1 and decrease of IL-10 in NR8383 cell line. Moreover, EGCG pretreatment reduced the total and the phosphorylated protein level of STAT1 in vivo and in vitro and reduced the phosphorylated protein level of JAK1 and JAK2. The present study demonstrates that EGCG ameliorates seawater aspiration-induced ALI via regulating inflammatory cytokines and inhibiting JAK/STAT1 pathway in rats.

Efficacy and safety of bronchoscopic cryotherapy for granular endobronchial tuberculosis.

Background: The most important sequela of endobronchial tuberculosis (EBTB) is bronchial stenosis, which causes wheezing, dyspnea and obstructive pneumonia. But there have been no reports about applying cryotherapy for granular EBTB that did not show luminal narrowing of the bronchus at diagnosis. Whether this technique is useful for preventing granular EBTB from progressing into stenosis needs to be clarified. Objective: To investigate the efficacy and safety of bronchoscopic cryotherapy for granular endobronchial tuberculosis. Methods: In this study, we analyzed the records of 76 patients with granular EBTB. Diagnosis of TB was confirmed by microbiology or histopathology. Bronchoscopic examinations revealed that the patients had granular endobronchial tuberculosis. Thirty-eight patients received bronchoscopic cryotherapy plus routine anti-tuberculosis chemotherapy and the other 38 patients received routine anti-tuberculosis chemotherapy alone. We compared the treatment effect of these 2 groups. The outcome measures were the changes of lesions, the rate of disappearance of lesions and complications of bronchoscopic cryotherapy. Results: The complete removal rate was 100% in patients with bronchoscopic cryotherapy plus routine anti-tuberculosis chemotherapy; the complete removal rate was 78.9% in patients with anti-tuberculosis chemotherapy alone; the rate of disappearance of lesions in the bronchoscopic cryotherapy plus routine anti-tuberculosis chemotherapy group was faster than that of the anti-tuberculosis chemotherapy alone group. There were no severe complications from bronchoscopic cryotherapy. Conclusions: Bronchoscopic cryotherapy can accelerate the healing of granular EBTB and help to prevent progressive bronchial stenosis due to granular EBTB and is a very safe method.

Application of bronchoscopic argon plasma coagulation in the treatment of tumorous endobronchial tuberculosis: Historical controlled trial

OBJECTIVE The purpose of this study was to evaluate the efficacy and safety of bronchoscopic argon plasma coagulation for tumorous endobronchial tuberculosis. METHODS We analyzed the records of 115 patients with tumorous endobronchial tuberculosis who did not show luminal narrowing of the bronchus at diagnosis. Of these 115 patients, 41 patients received bronchoscopic argon plasma coagulation plus routine antituberculosis chemotherapy (argon plasma coagulation group) and the other 74 patients received only routine antituberculosis chemotherapy (chemotherapy group). The treatment effects between these 2 groups were compared based on changes in lesions, rate of lesion disappearance, and complications associated with bronchoscopic argon plasma coagulation. RESULTS The complete removal rate was 100% in patients in argon plasma coagulation group. About 84.6% lesions disappeared completely in patients in the chemotherapy group. The rate of disappearance of lesions in the argon plasma coagulation group was faster than that of the chemotherapy group. There were no severe complications in the argon plasma coagulation group. CONCLUSIONS Bronchoscopic argon plasma coagulation can accelerate the healing of tumorous endobronchial tuberculosis and can help prevent progressive bronchial stenosis resulting from tumorous endobronchial tuberculosis, and it is a very safe method.

Lewis Lung Cancer Cells Promote SIGNR1(CD209b)‐Mediated Macrophages Polarization Induced by IL‐4 to Facilitate Immune Evasion

Tumor‐associated macrophages are a prominent component of lung cancer and contribute to tumor progression by facilitating the immune evasion of cancer cells. DC‐SIGN (CD209) assists in the immune evasion of a broad spectrum of pathogens and neoplasms by inhibiting the maturation of DCs and subsequent cytokines production. However, the expression of DC‐SIGN in macrophages and its role in mediating immune evasion in lung cancer and the underlying mechanism remain unclear. Our study aimed to identify the immunosuppressive role of SIGNR1 in murine macrophage differentiation and lung cancer progression. We found that SIGNR1‐positive RAW264.7 macrophages were enriched in mixed cultures with Lewis lung cancer cells (LLC) (ratio of RAW 264.7 to LLC being 1:1) after stimulation with IL‐4. Moreover, LLC‐educated macrophages exhibited significantly higher levels of IL‐10 but lower IL‐12 in response to IL‐4 treatment as determined by RT‐PCR and ELISA. However, inhibition of SIGNR1 markedly hampered the production of IL‐10, indicating that SIGNR1 was indispensable for IL‐4+LLC induced macrophage polarization towards the M2 subtype. Furthermore, polarized M2 cells immersed in a tumor microenvironment promoted the migration of LLCs, as measured by transwell assays, but migration was suppressed after blockade of SIGNR1 using CD209b antibody. In addition, IL‐4+LLC‐educated macrophages reduced the proliferation of the activated T cells and reduced IFN‐γ‐mediated Th1 response in T cells, while SIGNR1 inhibition rescued Th1 cell functions. In conclusion, murine SIGNR1 expressed in LLC‐educated macrophages appears to mediate IL‐4‐induced RAW264.7 macrophage polarization and thus facilitate lung cancer evasion. J. Cell. Biochem. 117: 1158–1166, 2016.

Electron Acceptors Induce Secretion of Enterotoxigenic Escherichia coli Heat-Labile Enterotoxin under Anaerobic Conditions through Promotion of GspD Assembly

ABSTRACT Heat-labile enterotoxin (LT), the major virulence factor of enterotoxigenic Escherichia coli (ETEC), can lead to severe diarrhea and promotes ETEC adherence to intestinal epithelial cells. Most previous in vitro studies focused on ETEC pathogenesis were conducted under aerobic conditions, which do not reflect the real situation of ETEC infection because the intestine is anoxic. In this study, the expression and secretion of LT under anaerobic or microaerobic conditions were determined; LT was not efficiently secreted into the supernatant under anaerobic or microaerobic conditions unless terminal electron acceptors (trimethylamine N-oxide dihydrate [TMAO] or nitrate) were available. Furthermore, we found that the restoration effects of TMAO and nitrate on LT secretion could be inhibited by amytal or ΔtorCAD and ΔnarG E. coli strains, indicating that LT secretion under anaerobic conditions was dependent on the integrity of the respiratory chain. At the same time, electron acceptors increase the ATP level of ETEC, but this increase was not the main reason for LT secretion. Subsequently, the relationship between the integrity of the respiratory chain and the function of the type II secretion system was determined. The GspD protein, the secretin of ETEC, was assembled under anaerobic conditions and was accompanied by LT secretion when TMAO or nitrate was added. Our data also demonstrated that TMAO and nitrate could not induce the GspD assembly and LT secretion in ΔtorCAD and ΔnarG strains, respectively. Moreover, GspD assembly under anaerobic conditions was assisted by the pilot protein YghG.

Discovery of a set of biomarkers of human lung adenocarcinoma through cell-map proteomics and bioinformatics

Carcinogenesis of lung adenocarcinoma remains unclear and very few biomarkers have been accepted for routine clinical use. In order to explore the pathogenesis and screen ideal biomarkers, we conducted cell-map proteomics study in human lung adenocarcinoma. Homogeneous lung adenocarcinoma cells were purified by laser capture microdissection (LCM). A high performance liquid chromatography (HPLC) system was used to separate the total solution proteins. The resulting MS/MS spectra were automatically searched for proteins against IPI human protein database using the TurboSEQUEST searching engine. Physico-chemical properties of the identified proteins, including molecular weight (MW), isoelectric point (PI), were described based on various proteomics web server and statistical analysis. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were used to analyze function of expressed proteins and screen candidate biomarkers according to biological annotation. A total of 843 distinct proteins were identified and were categorized as 10 sorts of molecular function and 17 sorts of biological process based on GO annotation. Further searching against KEGG pathways found that six proteins were involved in WNT signaling pathway, apoptosis pathway, Erb-2 signaling pathway, p53 signaling pathway, ubiquitin-mediated proteolysis and were might be hopefully screened as candidate markers of lung adenocarcinoma. The present study through LCM and cell-map proteomics showed a full view on the expressed protein profiles of lung adenocarcinoma. Several candidate markers are hopeful to be used as molecular targets of diagnosis, treatment and prognosis of lung adenocarcinoma.

Use of Interferon-γ release assay for the diagnosis of female genital tuberculosis in Northwest China

Female genital tuberculosis (FGTB) is one of the major causes of infertility. However, nonspecific manifestations and the lack of easy access to gold‐standard diagnostic test render a diagnostic difficult for FGTB. The objective of this study was to determine T‐SPOT.TB (an interferon‐γ release assay, IGRA) performance in patients with FGTB.

Heat-Labile Enterotoxin-Induced PERK-CHOP Pathway Activation Causes Intestinal Epithelial Cell Apoptosis

Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea among children and travelers in developing countries, and heat-labile enterotoxin (LT) is one of the most important virulence factors. The pathogenesis of and virulence factors associated with ETEC have been well-characterized; however, the extent to which ETEC damages host cells remains unclear. In this study, we found that LT could induce decreases in intestinal epithelial cell viability and induce apoptosis in a dose- and time- dependent manner in both HCT-8 and Caco-2 cells. We analyzed the expression profiles of apoptosis-related proteins via protein array technology and found that Bax, p-p53(S46), cleaved caspase-3, and TNFRI/TNFRSF1A expression levels were significantly up-regulated in wild-type ETEC- but not in ΔLT ETEC-infected HCT-8 cells. Bax is essential for endoplasmic reticulum (ER) stress-triggered apoptosis, and our RNAi experiments showed that the PERK-eIF2-CHOP pathway and reactive oxygen species (ROS) are also main participants in this process. LT-induced ROS generation was decreased in CHOP-knockdown HCT-8 cells compared to that in control cells. Moreover, pretreatment with the ROS inhibitor NAC down-regulated GRP78, CHOP, Bim, and cleaved caspase-3 expression, resulting in a reduction in the apoptosis rate from 36.2 to 20.3% in LT-treated HCT-8 cells. Furthermore, ROS inhibition also attenuated LT-induced apoptosis in the small intestinal mucosa in the ETEC-inoculation mouse model.