Effect and molecular mechanism of Sulforaphane alleviates brain damage caused by acute carbon monoxide poisoning:Network pharmacology analysis, molecular docking, and experimental evidence.

Sulforaphane (SFN) has attracted much attention due to its ability on antioxidant, anti-inflammatory, and anti-apoptotic properties, while its functional targets and underlying mechanism of action on brain injury caused by acute carbon monoxide poisoning (ACOP) have not been fully elucidated. Herein, we used a systematic network pharmacology approach to explore the mechanism of SFN in the treatment of brain damage after ACOP. In this study, the results of network pharmacology demonstrated that there were a total of 81 effective target genes of SFN and 36 drug-disease targets, which were strongly in connection with autophagy-animal signaling pathway, drug metabolism, and transcription disorders in cancer. Upon the further biological function and KEGG signaling pathway enrichment analysis, a large number of them were involved in neuronal death, reactive oxygen metabolic processes and immune functions. Moreover, based on the results of bioinformatics prediction associated with multiple potential targets and pathways, the AMP-activated protein kinase (AMPK) signaling pathway was selected to elucidate the molecular mechanism of SFN in the treatment of brain injury caused by ACOP. The following molecular docking analysis also confirmed that SFN can bind to AMPKα well through chemical bonds. In addition, an animal model of ACOP was established by exposure to carbon monoxide in a hyperbaric oxygen chamber to verify the predicted results of network pharmacology. We found that the mitochondrial ultrastructure of neurons in rats with ACOP was seriously damaged, and apoptotic cells increased significantly. The histopathological changes were obviously alleviated, apoptosis of cortical neurons was inhibited, and the number of Nissl bodies was increased in the SFN group as compared with the ACOP group (p < .05). Besides, the administration of SFN could increase the expressions of phosphorylated P-AMPK and MFN2 proteins and decrease the levels of DRP1, Caspase3, and Casapase9 proteins in the brain tissue of ACOP rats. These findings suggest that network pharmacology is a useful tool for traditional Chinese medicine (TCM) research, SFN can effectively inhibit apoptosis, protect cortical neurons from the toxicity of carbon monoxide through activating the AMPK pathway and may become a potential therapeutic strategy for brain injury after ACOP.

Chemical Constituents and α-Glucosidase Inhibitory, Antioxidant and Hepatoprotective Activities of Ampelopsis grossedentata.

Ampelopsis grossedentata is a valuable medicinal and edible plant, which is often used as a traditional tea by the Tujia people in China. A. grossedentata has numerous biological activities and is now widely used in the pharmaceutical and food industries. In this study, two new flavonoids (1-2) and seventeen known compounds (3-19) were isolated and identified from the dried stems and leaves of A. grossedentata. These isolated compounds were characterized by various spectroscopic data including mass spectrometry and nuclear magnetic resonance spectroscopy. All isolates were assessed for their α-glucosidase inhibitory, antioxidant, and hepatoprotective activities, and their structure-activity relationships were further discussed. The results indicated that compound 1 exhibited effective inhibitory activity against α-glucosidase, with an IC50 value of 0.21 µM. In addition, compounds 1-2 demonstrated not only potent antioxidant activities but also superior hepatoprotective properties. The findings of this study could serve as a reference for the development of A. grossedentata-derived products or drugs aimed at realizing their antidiabetic, antioxidant, and hepatoprotective functions.

Mechanisms of dihydromyricetin against hepatocellular carcinoma elucidated by network pharmacology combined with experimental validation.

CONTEXT: Dihydromyricetin (DMY) is extracted from vine tea, a traditional Chinese herbal medicine with anti-cancer, liver protection, and cholesterol-lowering effects. OBJECTIVE: This study investigated the mechanism of DMY against hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Potential DMY, HCC, and cholesterol targets were collected from relevant databases. PPI networks were created by STRING. Then, the hub genes of co-targets, screened using CytoHubba. GO and KEGG pathway enrichment, were performed by Metascape. Based on the above results, a series of in vitro experiments were conducted by using 40-160 µM DMY for 24 h, including transwell migration/invasion assay, western blotting, and Bodipy stain assay. RESULTS: Network pharmacology identified 98 common targets and 10 hub genes of DMY, HCC, and cholesterol, and revealed that the anti-HCC effect of DMY may be related to the positive regulation of lipid rafts. Further experiments confirmed that DMY inhibits the proliferation, migration, and invasion of HCC cells and reduces their cholesterol levels in vitro. The IC50 is 894.4, 814.4, 467.8, 1,878.8, 151.8, and 156.9 µM for 97H, Hep3B, Sk-Hep1, SMMC-7721, HepG2, and Huh7 cells, respectively. In addition, DMY downregulates the expression of lipid raft markers (CAV1, FLOT1), as well as EGFR, PI3K, Akt, STAT3, and Erk. DISCUSSION AND CONCLUSION: The present study reveals that DMY suppresses EGFR and its downstream pathways by reducing cholesterol to disrupt lipid rafts, thereby inhibiting HCC, which provides a promising candidate drug with low toxicity for the treatment of HCC.

[Chemical constituents of roots of Rodgersia aesculifolia].

The chemical compositions of Rodgersia aesculifolia were isolated and purified using a combination of silica gel, reverse phase silica gel, Sephadex LH-20 column chromatography, and semi-preparative HPLC. The structures were determined according to the physicochemical properties and spectroscopic data. The MTT method and the ABTS kit were used to measure the cytotoxicity and antioxidant capacity of all isolates, respectively. Thirty-four compounds were isolated from R. aesculifolia and elucidated as stigmastane-6ß-methoxy-3ß,5α-diol(1), stigmastane-3ß,5α,6ß triol(2), ß-sitosterol(3), ß-daucosterol(4), stigmast-4-en-3-one(5), bergenin(6), 11-ß-D-glucopyranosyl-bergenin(7), 11-O-galloybergenin(8), 1,4,6-tri-O-galloyl-ß-D-glucose(9), gallic acid(10), 3,4-dihydroxybenzoic acid methyl ester(11), ethyl gallate(12), ethyl 3,4-dihydroxybenzoate(13), caffeic acid ethyl ester(14), p-hydroxybenzeneacetic acid(15), 4-hydroxybenzoic acid(16), 2,3-dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-propan-1-one(17), 3,7-dimethyl-2-octene-1,7-diol(18), crocusatin-B(19), neroplomacrol(20), geniposide(21), 3-hydroxyurs-12-en-27-oic acid(22), 3ß-trans-p-coumaroyloxy-olean-12-en-27-oic acid(23), aceriphyllic acid G(24), isolariciresinol(25), trans-rodgersinine B(26), cis-rodgersinine A(27), neo-olivil(28),(7S,8R)-dihydro-3'-hydroxy-8-hydroxy-methyl-7-(4-hydroxy-3-methoxy phenyl)-1'-benzofuranpropanol(29), 5,3',4'-trihydroxy-7-methoxyflavanone(30), quercetin 3-rutinoside(31), catechin-[8,7-e]-4ß-(3,4-dihydroxy-phenyl)-dihydro-2(3H)-pyranone(32), ethyl α-L-arabino-furanoside(33), and l-linoleoylglycerol(34). One new compound was discovered(compound 1), 25 compounds were first isolated from R. aesculifolia, and 22 compounds were first isolated from the Rodgersia plant. The results indicated that compounds 22-24 possessed cytotoxicity for HepG2, MCF-7, HCT-116, BGC-823, and RAFLS cell lines(IC_(50) ranged from 5.89 µmol·L~(-1) to 20.5 µmol·L~(-1)). Compounds 8-14 and 30-32 showed good antioxidant capacity, and compound 9 showed the strongest antioxidant activity with IC_(50) of(2.00±0.12) µmol·L~(-1).

Pevonedistat Inhibits SOX2 Expression and Sphere Formation but Also Drives the Induction of Terminal Differentiation Markers and Apoptosis within Arsenite-Transformed Urothelial Cells.

Urothelial cancer (UC) is a common malignancy and its development is associated with arsenic exposure. Around 25% of diagnosed UC cases are muscle invasive (MIUC) and are frequently associated with squamous differentiation. These patients commonly develop cisplatin (CIS) resistance and have poor prognosis. SOX2 expression is correlated to reduced overall and disease-free survival in UC. SOX2 drives malignant stemness and proliferation in UC cells and is associated with development of CIS resistance. Using quantitative proteomics, we identified that SOX2 was overexpressed in three arsenite (As3+)-transformed UROtsa cell lines. We hypothesized that inhibition of SOX2 would reduce stemness and increase sensitivity to CIS in the As3+-transformed cells. Pevonedistat (PVD) is a neddylation inhibitor and is a potent inhibitor of SOX2. We treated non-transformed parent and As3+-transformed cells with PVD, CIS, or in combination and monitored cell growth, sphere forming abilities, apoptosis, and gene/protein expression. PVD treatment alone caused morphological changes, reduced cell growth, attenuated sphere formation, induced apoptosis, and elevated the expression of terminal differentiation markers. However, the combined treatment of PVD with CIS significantly elevated the expression of terminal differentiation markers and eventually led to more cell death than either solo treatment. Aside from a reduced proliferation rate, these effects were not seen in the parent. Further research is needed to explore the potential use of PVD with CIS as a differentiation therapy or alternative treatment for MIUC tumors that may have become resistant to CIS.

Identification of potential hub genes of gastric cancer.

BACKGROUND: Gastric cancer (GC) is a malignant tumor originated from gastric mucosa epithelium. It is the third leading cause of cancer mortality in China. The early symptoms are not obvious. When it is discovered, it has developed to the advanced stage, and the prognosis is poor. In order to screen for potential genes for GC development, this study obtained GSE118916 and GSE109476 from the gene expression omnibus (GEO) database for bioinformatics analysis. METHODS: First, GEO2R was used to identify differentially expressed genes (DEG) and the functional annotation of DEGs was performed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The Search Tool for the Retrieval of Interacting Genes (STRING) tool was used to construct protein-protein interaction (PPI) network and the most important modules and hub genes were mined. Real time quantitative polymerase chain reaction assay was performed to verify the expression level of hub genes. RESULTS: A total of 139 DEGs were identified. The functional changes of DEGs are mainly concentrated in the cytoskeleton, extracellular matrix and collagen synthesis. Eleven genes were identified as core genes. Bioinformatics analysis shows that the core genes are mainly enriched in many processes related to cell adhesion and collagen. CONCLUSION: In summary, the DEGs and hub genes found in this study may be potential diagnostic and therapeutic targets.

New Terpenoids from Potentilla freyniana Bornm. and Their Cytotoxic Activities.

Two new A-ring contracted triterpenoids, madengaisu A and madengaisu B, and one undescribed ent-kaurane diterpenoid, madengaisu C, along with 20 known compounds were isolated from the roots of Potentilla freyniana Bornm. The structures were elucidated using extensive spectroscopic techniques, including 1D and 2D-NMR, HR-ESI-MS, ECD spectra, IR, and UV analysis. Moreover, all isolated constituents were evaluated for their anti-proliferative activity against RA-FLS cells and cytotoxic activities against the human cancer cell lines Hep-G2, HCT-116, BGC-823, and MCF-7. Ursolic acid and pomolic acid displayed moderate inhibitory activity in RA-FLS cells with IC50 values of 24.63 ± 1.96 and 25.12 ± 1.97 µM, respectively. Hyptadienic acid and 2α,3ß-dihydroxyolean-12-en-28-oic acid 28-O-ß-d-glucopyranoside exhibited good cytotoxicity against Hep-G2 cells with IC50 values of 25.16 ± 2.55 and 17.66 ± 1.82 µM, respectively. In addition, 2α,3ß-dihydroxyolean-13(18)-en-28-oic acid and alphitolic acid were observed to inhibit HCT-116 cells (13.25 ± 1.65 and 21.62 ± 0.33 µM, respectively), while madengaisu B and 2α,3ß-dihydroxyolean-13(18)-en-28-oic acid showed cytotoxic activities against BGC-823 cells with IC50 values of 24.76 ± 0.94 and 26.83 ± 2.52 µM, respectively, which demonstrated that triterpenes from P. freyniana may serve as therapeutic agents for RA and cancer treatment.

Anti-inflammatory and antioxidant activities of chemical constituents from the flower buds of Buddleja officinalis.

Five new glycosides including mimenghuasu A and B (1-2), isolinarin (3), cyclocitralosides A and B (4-5), along with forty-seven known compounds were isolated from the flower buds of Buddleja officinalis. These structures were elucidated by extensive spectroscopic analysis (UV, IR, 1 D, 2 D NMR, and MS spectra). The anti-inflammatory activities of the isolated compounds were determined by enzyme-linked immunosorbent assay (ELISA) on the expression of TNF-α (LPS-activated RAW264.7 cells) and MTT experiment on LPS-induced HUVECs proliferation effects. Good suppressive effects on the expression of TNF-α were shown by 4 and 5 with IC50 values of 19.35 and 22.10 µM, respectively, compared to positive control indomethacin (IC50 16.40 µM). In addition to this, some isolated compounds exhibited excellent antioxidant activities including compounds 16, 18, 29, 39, and 47 (IC50 µM: 82.59, 72.94, 33.65, 46.67, and 20.81, respectively) with almost the same or stronger potency with reference to vitamin C as positive control (IC50 81.83 µM).

Neuroprotective effect of targeted regulatory Nrf2 gene on rats with acute brain injury induced by carbon monoxide poisoning.

Oxidative stress has been considered as an important cause of neurocyte damage induced by carbon monoxide (CO) poisoning; however, the precise mechanisms are not fully understood. The study aimed to elucidate the molecular mechanism and the neuroprotective effect of targeted regulatory nuclear factor erythroid2-related factor 2 (Nrf2) gene on acute brain injury in CO poisoning rats. An acute CO poisoning rat model was established by CO inhalation in hyperbaric oxygen chamber and followed by the administration of Nrf2 gene-loaded lentivirus. Mitochondrial membrane potential (ΔΨM), the levels of Nrf2, glutamate-cysteine ligase catalytic subunit (GCLC), catalase (CAT) and glutathione peroxidase (GSH-Px), and cell apoptosis were determined in brain tissue in rats. We found that CO poisoning could decrease ΔΨm of cells, slightly increase the expressions of Nrf2 and GCLC at mRNA and protein levels, reduce CAT and GSH-Px, and thus initiate apoptosis process. The Nrf2 gene treatment could obviously enhance the expressions of Nrf2 at mRNA and protein levels, and increase the concentrations of CAT and GSH-Px, maintain the ΔΨm of cells in brain tissue, significantly inhibit cell apoptosis as compared with the CO poisoning group (p < .05). These findings suggest that CO poisoning could induce oxidative stress and impair mitochondrial function of cells in brain tissue. The administration of Nrf2 gene could notably strengthen the antioxidant capacity of cells through regulating the downstream genes of Nrf2/antioxidant responsive element signal pathway, and positively protect cells against brain injury induced by acute severe CO poisoning.

Activation of PPARγ and inhibition of cell proliferation reduces key proteins associated with the basal subtype of bladder cancer in As3+-transformed UROtsa cells.

Environmental exposure to arsenite (As3+) has a strong association with the development of human urothelial cancer (UC) and is the 5th most common cancer in men and the 12th most common cancer in women. Muscle invasive urothelial cancer (MIUC) are grouped into basal or luminal molecular subtypes based on their gene expression profile. The basal subtype is more aggressive and can be associated with squamous differentiation, characterized by high expression of keratins (KRT1, 5, 6, 14, and 16) and epidermal growth factor receptor (EGFR) within the tumors. The luminal subtype is less aggressive and is predominately characterized by elevated gene expression of peroxisome proliferator-activated receptor- gamma (PPARγ) and forkhead box protein A1 (FOXA1). We have previously shown that As3+-transformed urothelial cells (As-T) exhibit a basal subtype of UC expressing genes associated with squamous differentiation. We hypothesized that the molecular subtype of the As-T cells could be altered by inducing the expression of PPARγ and/or inhibiting the proliferation of the cells. Non-transformed and As-T cells were treated with Troglitazone (TG, PPARG agonist, 10 µM), PD153035 (PD, an EGFR inhibitor, 1 µM) or a combination of TG and PD for 3 days. The results obtained demonstrate that treatment of the As-T cells with TG upregulated the expression of PPARγ and FOXA1 whereas treatment with PD decreased the expression of some of the basal keratins. However, a combined treatment of TG and PD resulted in a consistent decrease of several proteins associated with the basal subtype of bladder cancers (KRT1, KRT14, KRT16, P63, and TFAP2A). Our data suggests that activation of PPARγ while inhibiting cell proliferation facilitates the regulation of genes involved in maintaining the luminal subtype of UC. In vivo animal studies are needed to address the efficacy of using PPARγ agonists and/or proliferation inhibitors to reduce tumor grade/stage of MIUC.

Characterization and determination of cadmium resistance of CD133+/CD24+ and CD133-/CD24+ cells isolated from the immortalized human proximal tubule cell line, RPTEC/TERT1.

Stem/progenitor cells are involved in the regeneration of the renal tubules after damage due to a toxic insult. However, the mechanism involved in the regeneration of the tubules by the stem cells is not well understood due to the lack of immortal cell lines that represent the stem/progenitor cells of the kidney. A previous study from our laboratory has shown that the immortalized cell line RPTEC/TERT1 contains two populations of cells, one co-expressing CD24 and CD133, the other expressing CD24 only. The goal of the present study was to determine if both these populations could be sorted into separate independent cultures and if so, determine their characteristic features and response to the nephrotoxicant cadmium. The results of our study show that both the populations of cells could grow as independent cultures and maintain their phenotype after extended sub-culture. The CD133+/CD24+ co-expressing cells formed multicellular spheroids (nephrospheres), a characteristic feature of stem/progenitor cells, and formed branched tubule-like structures when grown on the surface of matrigel, whereas the CD133-/CD24+ cells were unable to form these structures. The CD133+/CD24+ cells were able to grow and undergo neurogenic, adipogenic, osteogenic, and tubulogenic differentiation, whereas the CD133-/CD24+ cells expressed some of the differentiation markers but were unable to grow in some of the specialized growth media. The CD133+/ CD24+ co-expressing cells had a shorter doubling time compared to the cells that expressed only CD24, and were more resistant to the toxic effects of the heavy metal, cadmium. In conclusion, the isolation and characterization of these two cell populations form the RPTEC/TERT1 cell line will facilitate the development of studies that determine the mechanisms involved in tubular damage and regeneration particularly after a toxic insult.

The urothelial cell line UROtsa transformed by arsenite and cadmium display basal characteristics associated with muscle invasive urothelial cancers.

Muscle invasive urothelial carcinomas are divided into various molecular subtypes with basal and luminal subtypes being the prominent ones. The basal muscle-invasive urothelial carcinomas are generally more aggressive at presentation and significantly enriched with squamous features. Our laboratory has developed an in-vitro model of urothelial cancer by transforming the immortalized cell line UROtsa with arsenite (As3+) and cadmium (Cd2+). In this study, we characterized the tumors formed by these transformed cell lines as more basal-like based on their gene expression patterns with increased expression of KRT1, KRT5, KRT6, KRT14, KRT16, KRT17 and CD44. In addition, histological examination of these tumor transplants showed squamous features enriched in basal muscle invasive urothelial carcinomas. The expression of these genes increased in the transformed cell lines as well as in the urospheres, which are putative cancer initiating cells/stem cells derived from the cell lines. There was also increased expression of these genes in the urospheres derived from the parent UROtsa cell line. Thus, our data shows that the As3+ and Cd2+-transformed cell lines and their derived tumor transplants have gene expression profiles similar to the basal subtype of muscle invasive bladder carcinomas with tumors having enriched squamous features. The increased expression of basal markers in the urospheres suggests that stem cells may be involved in the development of squamous differentiation seen in some of the muscle invasive bladder carcinomas.

The expression of keratin 6 is regulated by the activation of the ERK1/2 pathway in arsenite transformed human urothelial cells.

Urothelial cancers have an environmental etiological component, and previous studies from our laboratory have shown that arsenite (As+3) can cause the malignant transformation of the immortalized urothelial cells (UROtsa), leading to the expression of keratin 6 (KRT6). The expression of KRT6 in the parent UROtsa cells can be induced by the addition of epidermal growth factor (EGF). Tumors formed by these transformed cells have focal areas of squamous differentiation that express KRT6. The goal of this study was to investigate the mechanism involved in the upregulation of KRT6 in urothelial cancers and to validate that the As+3-transformed UROtsa cells are a model of urothelial cancer. The results obtained showed that the parent and the As+3-transformed UROtsa cells express EGFR which is phosphorylated with the addition of epidermal growth factor (EGF) resulting in an increased expression of KRT6. Inhibition of the extracellular-signal regulated kinases (ERK1/2) pathway by the addition of the mitogen-activated protein kinase kinase 1 (MEK1) and MEK2 kinase inhibitor U0126 resulted in a decrease in the phosphorylation of ERK1/2 and a reduced expression of KRT6. Immuno-histochemical analysis of the tumors generated by the As+3-transformed isolates expressed EGFR and tumors formed by two of the transformed isolates expressed the phosphorylated form of EGFR. These results show that the expression of KRT6 is regulated at least in part by the ERK1/2 pathway and that the As+3-transformed human urothelial cells have the potential to serve as a valid model to study urothelial carcinomas.

Clinicopathological and prognostic significance of Oct-4 expression in patients with non-small cell lung cancer: a systematic review and meta-analysis.

BACKGROUND: Octamer-binding transcription factor 4 (Oct-4) has been identified to participate in the tumorigenicity and malignancy of non-small cell lung cancer (NSCLC). However, its definite prognostic roles in NSCLC still remain a debate. Therefore, we conducted this meta-analysis to evaluate the prognostic value of Oct-4 expression in NSCLC and its relationship to some major clinicopathological characteristics. METHODS: A comprehensive literature retrieval was performed in PubMed, EMBASE and the Web of Science to identify the full-text articles that met our eligibility criteria. Odds ratio (OR) with 95% confidence interval (CI) severed as the summarized statistics for clinicopathological assessments, and hazard ratio (HR) with 95% CI served as the summarized statistics for prognostic assessments. Q-test and I(2)-statistic were used to evaluate the level of heterogeneity. Potential publication bias was detected by both Begg's test and Egger's test. RESULTS: There were 16 retried articles with 1,363 NSCLC cases included into this meta-analysis. Oct-4 expression was found to be significantly associated with the unfavorable outcomes for differentiation degree (OR: 3.065; 95% CI: 1.568-5.957; P=0.001), TNM stage (OR: 3.695; 95% CI: 2.252-6.063; P<0.001) and lymphatic metastasis (OR: 2.372; 95% CI: 1.504-3.742; P<0.001), but not associated with the histological subtypes, gender, age and smoking status. Oct-4 expression was also significantly associated with the poor prognosis of NSCLC (HR: 3.030; 95% CI: 2.283-4.021; P<0.001). The prognostic roles of Oct-4 expression in NSCLC still remained statistically reliable in the subgroups stratified by statistical analysis, patients' origins, positively-stained sites and histological subtypes. CONCLUSIONS: Our meta-analysis indicates that Oct-4 can serve as a strong biomarker predicting the poor clinicopathological and prognostic characteristics of NSCLC. More high-quality studies based on a large sample size will be very helpful to further validate and modify our findings in the future.

A systematic review and meta-analysis-does chronic obstructive pulmonary disease predispose to bronchopleural fistula formation in patients undergoing lung cancer surgery?

BACKGROUND: we conducted this systematic meta-analysis to determine the association between chronic obstructive pulmonary disease (COPD) and risk of bronchopleural fistula (BPF) in patients undergoing lung cancer surgery. METHODS: Literature retrieval was performed in PubMed, Embase and the Web of Science to identify the full-text articles that met our eligibility criteria. Odds ratio (OR) with 95% confidence interval (CI) served as the summarized statistics. Q-test and I(2)-statistic were used to evaluate the level of heterogeneity. Sensitivity analysis was performed to further examine the stability of pooled OR. Publication bias was detected by both Begg's test and Egger's test. RESULTS: Eight retrospective observational studies were included into this meta-analysis. The overall summarized OR was 2.03 (95% CI: 1.44-2.86; P<0.001), revealing that COPD was significantly associated with the risk of BPF after lung cancer surgery. In subgroup analysis, the relationship between COPD and BPF occurrence remained statistically prominent in the subgroups stratified by statistical analysis (univariate analysis, OR: 1.91; 95% CI: 1.35-2.69; P<0.001; multivariate analysis, OR: 3.18; 95% CI: 1.95-5.19; P<0.001), operative modes (pneumonectomy, OR: 2.11; 95% CI: 1.15-3.87; P=0.016) and in non-Asian populations (OR: 2.36; 95% CI: 1.18-4.73; P=0.016). No significant impact of COPD on BPF risk was observed in Asian patients (OR: 1.48; 95% CI: 0.85-2.57; P=0.16). No significant heterogeneity or publication bias was discovered across the included studies. CONCLUSIONS: Our meta-analysis indicates that COPD can significantly predispose to BPF formation in patients undergoing lung cancer surgery. Because some limitations still exist in this meta-analysis, our findings should be further verified and modified in the future.

Elevated connexin 43 expression in arsenite-and cadmium-transformed human bladder cancer cells, tumor transplants and selected high grade human bladder cancers.

Connexin 43 has been shown to play a role in cell migration and invasion; however, its role in bladder cancer is not well defined. Previous studies from our laboratory have shown that the environmental pollutants arsenite and cadmium can cause malignant transformation of the immortalized urothelial cell line UROtsa. These transformed cells can form tumors in immune-compromised mice. The goal of the present study was to determine if connexin 43 is expressed in the normal human bladder, the arsenite and cadmiun-transformed UROtsa cells as well as human urothelial cancer. The results obtained showed that connexin 43 is not expressed in the epithelial cells of the human bladder but is expressed in immortalized cultures of human urothelial cells and the expression is variable in the arsenite and cadmium- transformed urothelial cell lines derived from these immortalized cells. Tumor heterotransplants generated from the transformed cells expressed connexin 43 and the expression was localized to areas of squamous differentiation. Immuno-histochemical analysis of human bladder cancers also showed that the expression of connexin 43 was localized to areas of the tumor that showed early features of squamous differentiation. Treatment of UROtsa cells with various concentrations of arsenite or cadmium did not significantly alter the expression level of connexin 43. In conclusion, our results show that the expression of connexin 43 is localized to the areas of the tumor that show squamous differentiation, which may be an indicator of poor prognosis. This suggests that connexin 43 has the potential to be developed as a biomarker for bladder cancer that may have the ability to invade and metastasize.

Upregulation of long noncoding RNA SPRY4-IT1 promotes metastasis of esophageal squamous cell carcinoma via induction of epithelial-mesenchymal transition.

Esophageal squamous cell carcinoma (ESCC) is one of the prevalent and deadly cancers worldwide, especially in Eastern Asia. Recent studies show that long noncoding RNAs (lncRNAs) have critical roles in diverse biological processes, including tumorigenesis. In the present study, we find that the expression of lncRNA SPRY4-IT1 is significantly upregulated in ESCC cell lines as compared with human esophageal epithelial cell line HEEC. Overexpression of SPRY4-IT1 can increase in vitro motility of ESCC cells via induction of epithelial-mesenchymal transition (EMT), which is characterized by increasing the expression of vimentin (Vim) and fibronectin (FN) with a concomitant decrease of E-cadherin (E-Cad) and ZO-1, while silencing of SPRY4-IT1 significantly inhibits the in vitro motility of ESCC cells. Further, the knockdown of SPRY4-IT1 also significantly attenuates TFG-ß-induced EMT of ESCC cells. Further, lncRNA SPRY4-IT1 can directly increase the transcription, expression, and nuclear localization of Snail, one key transcription factor during the EMT processes of cancer cells, while siRNA-mediated specific knockdown of Snail can significantly attenuate SPRY4-IT1-induced EMT of ESCC cells. Our results suggest that lncRNA SPRY4-IT1 might be considered as a novel oncogene involved in ESCC progression.

Loss of N-Cadherin Expression in Tumor Transplants Produced From As+3- and Cd+2-Transformed Human Urothelial (UROtsa) Cell Lines.

BACKGROUND: Epithelial to mesenchymal transition is a process in which a cell experiences a loss of epithelial cell characteristics and acquires a more mesenchymal cell phenotype. In cancer, epithelial to mesenchymal transition has been proposed to play an important role during specific stages of tumor progression. The role epithelial to mesenchymal transition and mesenchymal to epithelial transition might play in toxicant-induced urothelial cancer is unknown. METHODS: Real-time PCR, Western blotting, immuno-histochemistry and immuno-fluorescence were used to determine the expression of E- and N-cadherin in the UROtsa parent, the As+3- and Cd+2-transformed cell lines, the spheroids isolated from these cell lines as well as the tumor heterotransplants that were produced by the injection of the transformed cells into immune compromised mice. RESULTS: This study showed that N-cadherin expression was increased in 6 As+3- and 7 Cd+2- transformed cell lines generated from human urothelial cells (UROtsa). The expression varied within each cell line, with 10% to 95% of the cells expressing N-cadherin. Tumors produced from these cell lines showed no expression of the N-cadherin protein. Spheroids which are made up of putative cancer initiating cells produced from these cell lines showed only background expression of N-cadherin mRNA, increased expression of aldehyde dehydrogenase 1 mRNA and produced tumors which did not express N-cadherin. There was no change in the expression of E-cadherin in the tumors, and the tumors formed by all the As+3 and Cd+2-transformed cell lines and cancer initiating cells stained intensely and uniformly for E-cadherin. CONCLUSIONS: The finding that the cells expressing N-cadherin gave rise to tumors with no expression of N-cadherin is in agreement with the classical view of epithelial to mesenchymal transition. Epithelial to mesenchymal transition and N-cadherin are associated with dissemination and not with the ability to establish new tumor growth. Mesenchymal to epithelial transition and E-cadherin are viewed as necessary for a cell to establish a new metastatic site. The lack of N-cadherin expression in tumor transplants is consistent with E-cadherin expressing cells "seeding" a site for tumor growth. The study shows that a minority population of cultured cells can be the initiators of tumor growth.

SPARC Expression Is Selectively Suppressed in Tumor Initiating Urospheres Isolated from As+3- and Cd+2-Transformed Human Urothelial Cells (UROtsa) Stably Transfected with SPARC.

BACKGROUND: This laboratory previously analyzed the expression of SPARC in the parental UROtsa cells, their arsenite (As(+3)) and cadmium (Cd(+2))-transformed cell lines, and tumor transplants generated from the transformed cells. It was demonstrated that SPARC expression was down-regulated to background levels in Cd(+2)-and As(+3)-transformed UROtsa cells and tumor transplants compared to parental cells. In the present study, the transformed cell lines were stably transfected with a SPARC expression vector to determine the effect of SPARC expression on the ability of the cells to form tumors in immune-compromised mice. METHODS: Real time PCR, western blotting, immunohistochemistry, and immunofluorescence were used to define the expression of SPARC in the As(+3)-and Cd(+2)-transformed cell lines, and urospheres isolated from these cell lines, following their stable transfection with an expression vector containing the SPARC open reading frame (ORF). Transplantation of the cultured cells into immune-compromised mice by subcutaneous injection was used to assess the effect of SPARC expression on tumors generated from the above cell lines and urospheres. RESULTS: It was shown that the As(+3)-and Cd(+2)-transformed UROtsa cells could undergo stable transfection with a SPARC expression vector and that the transfected cells expressed both SPARC mRNA and secreted protein. Tumors formed from these SPARC-transfected cells were shown to have no expression of SPARC. Urospheres isolated from cultures of the SPARC-transfected As(+3)-and Cd(+2)-transformed cell lines were shown to have only background expression of SPARC. Urospheres from both the non-transfected and SPARC-transfected cell lines were tumorigenic and thus fit the definition for a population of tumor initiating cells. CONCLUSIONS: Tumor initiating cells isolated from SPARC-transfected As(+3)-and Cd(+2)-transformed cell lines have an inherent mechanism to suppress the expression of SPARC mRNA.

The role of CCL20/CCR6 axis in recruiting Treg cells to tumor sites of NSCLC patients.

Inflammatory chemokine CCL20 and its receptor CCR6 have been reported to correlate with colorectal cancer patients' metastasis. However, the role of CCL20 in patients with NSCLC is not well defined. In this study, we detected the expression of CCL20 in tumor samples and corresponding adjacent ones (n=71) from patients with NSCLC using RT-PCR and observed that CCL20 showed higher expression in tumor samples (0.28±0.17) than in adjacent ones (0.20±0.13) (n=71, P=0.0056), which was also verified in protein level using IHC. Analysis results showed that CCL20 expression was positively associated with CD4 (n=80, P=0.0046), Foxp3 (n=80, P=0.0020) and IL-10 (n=61, P=0.0003) in tumor samples. And the flow data showed that Treg cells accumulated in TIL (MFI: 961±760) compared with PBMC (MFI: 683±460) (n=40, P=0.0046); and the percentage of CCR6 - the sole receptor of CCL20 - on Treg cells was higher in TIL (MFI: 1311±1268) than in PBMC (MFI: 976±780) (n=40, P=0.0219). It was interesting to find that the expression of CCL20 in tumor sites was almost 1.5-fold higher in samples from high-stage patients (III-IV stage, 0.34±0.17) compared with those from low-stage patients (I-II stage, 0.22±0.11) (P=0.0056). Furthermore, the higher expression of CCL20 was associated with a lower overall survival (P=0.0198). The IHC data showed that tumor cells were the main source of CCL20, and after treated cell line A549 with docetaxel, we found that the secretion of CCL20 was decreased heavily (n=3, P=0.0046). Our results demonstrated that CCL20 cooperated with CCR6 could recruit Treg cells to tumor sites, and chemotherapy medicine docetaxel could decrease the expression of CCL20.