A Novel Biological Activity of the STAT3 Inhibitor Stattic in Inhibiting Glutathione Reductase and Suppressing the Tumorigenicity of Human Cervical Cancer Cells via a ROS-Dependent Pathway.

INTRODUCTION: Glutathione reductase (GSR) provides reduced glutathione (GSH) to maintain redox homeostasis. Inhibition of GSR disrupts this balance, resulting in cell damage, which benefits cancer therapy. However, the effect of GSR inhibition on the tumorigenicity of human cervical cancer is not fully understood. MATERIALS AND METHODS: Tissue microarray analysis was employed to determine GSR expression in cervical cancer tissues by immunohistochemical staining. Cell death was measured with PI/FITC-annexin V staining. mRNA levels were measured via quantitative RT-PCR. Protein expression was measured by Western blotting and flow cytometry. STAT3 deletion was performed with CRISPR/Cas9 technology. GSR knockdown was achieved by RNA interference. Reactive oxygen species (ROS) levels were measured by DCF staining. GSR enzymatic activity was measured with a GSR assay kit. The effect of GSR inhibition on the growth of tumors formed by cervical cancer cells was investigated using a xenograft model. RESULTS: The expression of GSR was increased in human cervical cancer tissues, as shown by immunohistochemical staining. GSR knockdown by RNA interference in human cervical cancer cell lines resulted in cell death, suggesting the ability of GSR to maintain cancer cell survival. The STAT3 inhibitor 6-nitrobenzo[b]thiophene 1,1-dioxide (Stattic) also inhibited the enzymatic activity of GSR and induced the death of cervical cancer cells. More importantly, Stattic decreased the growth of xenograft tumors formed by cervical cancer cells in nude mice. Mechanistically, tumor cell death induced by Stattic-mediated GSR inhibition was ROS-dependent, since the ROS scavengers GSH and N-acetyl cysteine (NAC) reversed the effect of Stattic. In contrast, pharmacological and molecular inhibition of STAT3 did not induce the death of cervical cancer cells, suggesting a STAT3-independent activity of Stattic. CONCLUSION: Stattic inhibits the enzymatic activity of GSR and induces STAT3-independent but ROS-dependent death of cervical cancer cells, suggesting its potential application as a therapeutic agent for human cervical cancers.

[Diagnostic value of different detection methods for Mycobacterium tuberculosis in bronchoalveolar lavage fluid from pulmonary tuberculosis patients].

OBJECTIVE: To investigate the diagnostic value of different detection methods for Mycobacterium tuberculosis in bronchoalveolar lavage fluid (BALF) from patients with pulmonary tuberculosis.
 Methods: BALF from100 patients in Changsha Central Hospital from January 2013 to December 2015 was collected. Among 100 patients, 65 cases were clinically diagnosed as tuberculosis, and 35 cases served as control. BALF smear method, polymerase chain reaction (PCR) and membrane reverse dot blot (RDB) were used for synchronous detection of Mycobacterium tuberculosis.
 Results: The positive rates by BALF smear method, PCR and RDB were 43.08%, 73.84% and 92.31%, respectively (P<0.05). Sensitivity, specificity, accuracy, and negative predictive value for BALF smear were 43.08%, 88.57%, 59.00%, and 45.59%, respectively; for PCR were 73.85%, 100%, 83.00%, and 67.31%, respectively; for RDB were 92.31%, 100.00%, 95.00%, and 87.50%, respectively.
 Conclusion: The technique of membrane RDB can not only accurately diagnose Mycobacterium tuberculosis, but also can rapidly and easily identify the resistance of Mycobacterium tuberculosis to streptomycin (SM), rifampicin (RFP) and isoniazid (INH) genotypes. It possesses high clinical value.

Pro-Inflammatory Cytokine IL-1ß Up-Regulates CXC Chemokine Receptor 4 via Notch and ERK Signaling Pathways in Tongue Squamous Cell Carcinoma.

Chronic inflammation contributes to tumor development through the induction of oncogenic mutations, genomic instability, early tumor promotion, and enhanced angiogenesis. Here, we report that IL-1 receptor 1 (IL-1R1) was expressed in 40 of 41 human tongue squamous cell carcinomas (TSCC). IL-1ß up-regulated the expression of CXCR4, a CXC chemokine receptor that mediates cancer growth and metastasis, at both mRNA and protein levels in Tca8113 TSCC cells. IL-1ß treatment of Tca8113 cells promoted migration in response to CXCR4 ligand stromal-derived factor α (SDF-1α). The inhibition of IL-1R1 by its antagonist IL-1Ra or RNA interference significantly reversed the up-regulation of CXCR4 induced by IL-1ß. IL-1R1 activation also up-regulated the expression of IL-1ß itself, suggesting a positive feedback regulation of CXCR4 expression. Furthermore, IL-1ß induced the activation of Notch, which was originally considered a stem cell regulator. Pharmacological inhibition of Notch signaling reversed the up-regulation of CXCR4 induced by IL-1ß, suggesting that Notch signaling may be involved in the growth and metastasis of cancers via up-regulation of CXCR4. In addition, IL-1ß induced the activation of extracellular signal regulated kinase (ERK) and ERK inhibition decreased the up-regulation of CXCR4 induced by IL-1ß, suggesting the involvement of ERK signaling in cancer metastasis. Taken together these data suggest that IL-1ß and IL-1R1 promote cancer growth and metastasis by up-regulating CXCR4 expression and that CXCR4 may be a link between inflammation and cancer.

Gut-lung crosstalk in pulmonary involvement with inflammatory bowel diseases.

Pulmonary abnormalities, dysfunction or hyper-reactivity occurs in association with inflammatory bowel disease (IBD) more frequently than previously recognized. Emerging evidence suggests that subtle inflammation exists in the airways among IBD patients even in the absence of any bronchopulmonary symptoms, and with normal pulmonary functions. The pulmonary impairment is more pronounced in IBD patients with active disease than in those in remission. A growing number of case reports show that the IBD patients develop rapidly progressive respiratory symptoms after colectomy, with failure to isolate bacterial pathogens on repeated sputum culture, and often request oral corticosteroid therapy. All the above evidence indicates that the inflammatory changes in both the intestine and lung during IBD. Clinical or subclinical pulmonary inflammation accompanies the main inflammation of the bowel. Although there are clinical and epidemiological reports of chronic inflammation of the pulmonary and intestinal mucosa in IBD, the detailed mechanisms of pulmonary-intestinal crosstalk remain unknown. The lung has no anatomical connection with the main inflammatory site of the bowel. Why does the inflammatory process shift from the gastrointestinal tract to the airways? The clinical and subclinical pulmonary abnormalities, dysfunction, or hyper-reactivity among IBD patients need further evaluation. Here, we give an overview of the concordance between chronic inflammatory reactions in the airways and the gastrointestinal tract. A better understanding of the possible mechanism of the crosstalk among the distant organs will be beneficial in identifying therapeutic strategies for mucosal inflammatory diseases such as IBD and allergy.