[Effect of epithelial-mesenchymal transition on cardiac fibrosis induced by oil mist particulate matter].

Objective: To investigate the effects of oil-mist particulate matter (OMPM) on cardiac tissue structure fibrosis in rats and the role of epithelial-mesenchymal transition (EMT). Methods: Six-week-old Wistar rats (half male and half female) were randomly divided into 3 groups: control group (without OMPM exposure), low-dose exposure group (50 mg/m3) and high-dose exposure group (100 mg/m3), 18 rats in each group, with 6.5 hours per day of dynamic inhalation exposure. After 42 days of continuous exposure, cardiac tissues were collected for morphological observation; Western blot was used to detect fibrosis markers collagen I and collagen III levels, epithelial marker E-cadherin levels, interstitial markers N-cadherin, fibronectin, vimentin, alpha-smooth muscle actin (α-SMA) levels, and EMT transcription factor Twist protein levels; Real-time polymerase chain reaction (RT-qPCR) was used to detect collagen I and collagen III mRNA levels. Results: After OMPM exposure, myocardial cell edema and collagen fiber deposition were increased gradually with increasing exposure dose. Western blot results showed that compared with the control group, the expression levels of collagen I, collagen III, N-Cadherin, fibronectin, vimentin, α-SMA, and Twist protein were increased significantly in the low-dose exposure group and the high-dose exposure group (P＜0.01), and protein expression levels were higher in the high-dose exposure group than those in the low-dose exposure group (P＜0.01). In contrast, E-Cadherin protein expression levels were decreased significantly, and lower in the high-dose exposure group (P＜0.01). RT-qPCR results showed that compared with the control group, collagen I and collagen III mRNA levels were increased significantly in the low-dose exposure group and the high-dose exposure group (P＜0.01), and were increased with increasing exposure dose. (P＜0.01). Conclusion: OMPM may induce cardiac fibrosis in rats by promoting EMT process.

Identification of apoptosis-associated protein factors distinctly expressed in cigarette smoke condensate-exposed airway bronchial epithelial cells.

Smoking is associated with an increased risk of respiratory diseases, including lung cancer and asthma. However, the mechanisms or diagnostic markers for smoking-related diseases remain largely unknown. Here we investigated the role of cigarette smoke condensate (CSC) in the regulation of human bronchial epithelial cell (BEAS-2B) behavior. We found that exposure to CSC significantly inhibited BEAS-2B cell viability, impaired cell morphology, induced cell apoptosis, triggered oxidative damage, and promoted inflammatory response, which suggests a deleterious effect of CSC on bronchial epithelial cells. In addition, CSC markedly altered the expression of apoptosis-associated protein factors, including p21, soluble tumor necrosis factor receptor 1, and Fas ligand. In sum, our study identified a panel of novel protein factors that may mediate the actions of CSC on bronchial epithelial cells and have a predictive value for the development and progression of smoking-related diseases, thus providing insights into the development of potential diagnostic and therapeutic strategies against these diseases.

Downregulation of phosphorylated MKK4 is associated with a poor prognosis in colorectal cancer patients.

Mitogen-activated protein kinase kinase 4 (MKK4) is a key mediator of Jun N-terminal kinase signaling and influences malignant metastasis. Here, we used immunohistochemistry to assess phosphorylated MMK4 (pMKK4) levels and examine their association with the clinicopathological features of a pilot set of patient samples consisting of normal colonic mucosa (NCM), colorectal adenoma (CA), and colorectal cancer (CRC) tissues. pMKK4 levels were also assessed in a validation set of CRC cases with accompanying follow-up data to confirm their clinicopathological and prognostic significance. pMKK4 levels, which were high in 79.17% of NCM samples, were downregulated in 33.33% of CA and 63.54% of CRC samples. pMKK4 downregulation was associated with metastasis, especially to the liver. In the validation set, pMKK4 downregulation was associated with increases in invasive depth, lymph node metastasis, distant metastasis, and TNM stage. Univariate analysis indicated that pMKK4 score, tumor differentiation, and TNM stage were correlated with disease-free survival and overall survival. Multivariate analysis indicated that decreased pMKK4 expression was an independent risk factor for disease-free survival in CRC patients. These results suggest that CRC patients with low pMKK4 immunochemistry scores should be monitored carefully for early detection of possible recurrences, especially liver metastasis.

Inhibition of ERRα suppresses epithelial mesenchymal transition of triple negative breast cancer cells by directly targeting fibronectin.

Triple-negative breast cancer (TNBC) patients have poor prognosis due to the aggressive metastatic behaviors. Our study reveals that expression of estrogen related receptor α (ERRα) is significantly (p < 0.01) positively associated with high grade tumors and lymph node metastasis, while negatively correlated with overall survival (OS), in 138 TNBC patients. Targeted inhibition of ERRα by its inverse agonist XCT-790 or si-RNA obviously inhibits in vitro motility of TNBC cells. While over expression of ERRα triggers the invasion and migration of TNBC cells. Further, si-ERRα and XCT-790 inhibit the epithelial mesenchymal transition (EMT) of TNBC cells with increasing the expression of E-cadherin and decreasing fibronectin (FN) and vimentin. While XCT-790 has no effect on the expression of EMT related transcription factors such as Snail or Slug. Further, inhibitors of MAPK, PI3K/Akt, NF-κB signal molecules, which are activated by XCT-790, can not attenuate the suppression effects of XCT-790 on EMT. Alternatively, luciferase reporter gene assays and ChIP analysis indicate that ERRα can directly bind with FN promoter at ERR response element-3 (ERRE-1), ERRE-3, and ERRE-4, while XCT-790 reduces this bond. In vivo data show that ERRα expression is significantly (p < 0.05) correlated with FN in clinical TNBC patients. In MDA-MB-231 tumor xenograft models, XCT-790 decreases the expression of FN, inhibits the growth and lung metastasis, and suppresses the EMT. Our results demonstrate that ERRα functions as a metastasis stimulator and its targeted inhibition may be a new therapeutic strategy for TNBC treatment.

Bisphenol A modulates colorectal cancer protein profile and promotes the metastasis via induction of epithelial to mesenchymal transitions.

More and more evidences indicate that endocrine disruptor chemicals such as bisphenol A (BPA) can act as carcinogens and enhance susceptibility to tumorigenesis. Although the gut is in direct contact with orally ingested BPA, effects of BPA on occurrence and development of colorectal cancer remain an unexplored endpoint. Colorectal cancer SW480 cells treated with nanomolar (10(-8) M) or greater (10(-5) M) concentrations of BPA were compared with responses of a control group. Proteomic study revealed that more than 56 proteins were modulated following exposure to BPA, which are relevant to structure, motility and proliferation of cells, production of ATP, oxidative stress, and protein metabolism. Further studies revealed that BPA increased migration and invasion and triggered transformations from epithelial to mesenchymal transitions (EMTs) of colorectal cancer cells, which was characterized by acquiring mesenchymal spindle-like morphology and increasing the expression of N-cadherin with a concomitant decrease of E-cadherin. Accordingly, BPA treatment increased the expression of transcription factor Snail. Furthermore, signal AKT/GSK-3ß-mediated stabilization of Snail is involved during BPA-induced EMT of colon cancer cells. Our study first demonstrated that the xenoestrogen BPA at nanomolar and greater concentrations modulates the protein profiles and promotes the metastasis of colorectal cancer cells via induction of EMT.

Exploring the chemodiversity and biological activities of the secondary metabolites from the marine fungus Neosartorya pseudofischeri.

The production of fungal metabolites can be remarkably influenced by various cultivation parameters. To explore the biosynthetic potentials of the marine fungus, Neosartorya pseudofischeri, which was isolated from the inner tissue of starfish Acanthaster planci, glycerol-peptone-yeast extract (GlyPY) and glucose-peptone-yeast extract (GluPY) media were used to culture this fungus. When cultured in GlyPY medium, this fungus produced two novel diketopiperazines, neosartins A and B (1 and 2), together with six biogenetically-related known diketopiperazines,1,2,3,4-tetrahydro-2, 3-dimethyl-1,4-dioxopyrazino[1,2-a]indole (3), 1,2,3,4-tetrahydro-2-methyl-3-methylen e-1,4-dioxopyrazino[1,2-a]indole (4), 1,2,3,4-tetrahydro-2-methyl-1,3,4-trioxopyrazino[1,2-a] indole (5), 6-acetylbis(methylthio)gliotoxin (10), bisdethiobis(methylthio)gliotoxin (11), didehydrobisdethiobis(methylthio)gliotoxin (12) and N-methyl-1H-indole-2-carboxamide (6). However, a novel tetracyclic-fused alkaloid, neosartin C (14), a meroterpenoid, pyripyropene A (15), gliotoxin (7) and five known gliotoxin analogues, acetylgliotoxin (8), reduced gliotoxin (9), 6-acetylbis(methylthio)gliotoxin (10), bisdethiobis(methylthio) gliotoxin (11) and bis-N-norgliovictin (13), were obtained when grown in glucose-containing medium (GluPY medium). This is the first report of compounds 3, 4, 6, 9, 10 and 12 as naturally occurring. Their structures were determined mainly by MS, 1D and 2D NMR data. The possible biosynthetic pathways of gliotoxin-related analogues and neosartin C were proposed. The antibacterial activity of compounds 2-14 and the cytotoxic activity of compounds 4, 5 and 7-13 were evaluated. Their structure-activity relationships are also preliminarily discussed.

[Expression and clinicopathological significance of serine-257/threonine-261 phosphorylated MKK4 in colorectal carcinoma].

OBJECTIVE: As an activator of JNK and p38, phosphorylated MKK4 is considered to be associated with tumor progression and prognosis. This study was to examine the expression of pMKK4 and evaluate its prognostic significance in colorectal carcinoma. METHODS: A total of 343 cases of colorectal cancer were followed up to analyze the associations between the expression of pMKK4 and various clinicopathological factors. The expression of Serine-257/Threonine-261 pMKK4 was detected immunohistochemically by tissue microarray. RESULTS: The staining of pMKK4 was present in cytoplasm of colorectal carcinoma. And the expression of pMKK4 was correlated with invasion depth (P = 0.003), differentiation (P = 0.018), lymph node metastasis (P < 0.001), metastasis (P < 0.001), hepatic metastasis (P = 0.039) and TNM stage (P < 0.001). The patients with strong pMKK4 staining had a better overall survival than those with lowered levels (Log rank = 4.531, P = 0.033). Univariate analysis indicated that the expression of pMKK4 was correlated with either overall survival (HR = 0.785, P = 0.035) or relapse-free survival (HR = 0.788, P = 0.044). In multivariate analysis, there was no prognostic significance of pMKK4 after adjusting for invasion depth, differentiation, lymph node metastasis, metastasis, liver metastasis and TNM stage. CONCLUSIONS: The down-regulation of S257/T261 pMKK4 is associated with more advanced stages and it plays an important role in tumor progression. A high-level expression of pMKK4 indicates favorable clinical outcomes, but it is not an independent predictor.

Single wall carbon nanotube induced inflammation in cruor-fibrinolysis system.

OBJECTIVE: To study single wall carbon nanotubes (SWCNT) and its role in inducing inflammatory cytokines in the cruor-fibrinolysis system of rat. METHODS: Twenty one Wistar rats were divided into four groups: 1) control; 2) low-dose SWCNT (0.15 mg/kg BW); 3) medium-dose SWCNT (0.75 mg/kg BW); 4) high-dose SWCNT (1.5 mg/kg BW). Intratracheal instillation of SWCNT suspensions was administered to rats once per day for 21 days. In order to assess the exposure effect of SWCNT to the rats, activity of Inflammatory cytokine was measured and markers of cruor-fibrinolysis system were studied via ELSIA. Also, change in clotting time was recorded and histopathology was studied. RESULTS: IL-6 and IL-8 concentrations of rats exposed to SWCNT were significantly higher than those in controls (P<0.05). The activity of inflammatory cytokines and histopathological change indicated that oxidative damage occurred. Change in clotting time in rats exposed to SWCNT decreased compared with controls. Meanwhile, t-PA (tissue-tupe plassminogen activator) and AT-III (antithrombin-III) levels in rats exposed to particulates increased or decreased significantly compared with controls (P<0.05). A similar trend was observed for D-dimer (D2D) levels, indicating that SWCNT can impact the cruor-fibrinolysis system of rat. CONCLUSION: The results from our study suggest that an increased procoagulant activity and reduced fibrinolytic activity in rats exposed to SWCNT can cause pulmonary oxidative stress and inflammation, due to the release of pro-thrombotic and inflammatory cytokines into the blood circulation of rat.

Single-wall carbon nanotubes induce oxidative stress in rat aortic endothelial cells.

Oxidative stress is a major factor contributing to endothelial cell damage. Single-wall carbon nanotubes (SWCNTs) have oxidative properties; however, the oxidative effects of SWCNTs on endothelial cells are not fully understood. In the present study, we investigated the effects of oxidative stress induced by SWCNTs on rat aortic endothelial cells (RAECs). Various markers of cellular damage were assessed, such as biochemical and ES immunity indexes, and DNA and protein damage. Our findings suggest that RAEC endured oxidative damage following SWCNT exposure. Specifically, after SWCNTs exposure, non-enzymatic antioxidant glutathione was activated prior to superoxide dismutase activation in order to defend against oxidative stress. Additionally, it was found that as SWCNT concentration increased, so did the stress protein, heme oxygenase-1 (HO-1), expression levels. These changes may induce RAEC damage, and result in many serious diseases.

Serum metabolic profiling of human gastric cancer based on gas chromatography/mass spectrometry

Research on molecular mechanisms of carcinogenesis plays an important role in diagnosing and treating gastric cancer. Metabolic profiling may offer the opportunity to understand the molecular mechanism of carcinogenesis and help to non-invasively identify the potential biomarkers for the early diagnosis of human gastric cancer. The aims of this study were to explore the underlying metabolic mechanisms of gastric cancer and to identify biomarkers associated with morbidity. Gas chromatography/mass spectrometry (GC/MS) was used to analyze the serum metabolites of 30 Chinese gastric cancer patients and 30 healthy controls. Diagnostic models for gastric cancer were constructed using orthogonal partial least squares discriminant analysis (OPLS-DA). Acquired metabolomic data were analyzed by the nonparametric Wilcoxon test to find serum metabolic biomarkers for gastric cancer. The OPLS-DA model showed adequate discrimination between cancer and non-cancer cohorts while the model failed to discriminate different pathological stages (I-IV) of gastric cancer patients. A total of 44 endogenous metabolites such as amino acids, organic acids, carbohydrates, fatty acids, and steroids were detected, of which 18 differential metabolites were identified with significant differences. A total of 13 variables were obtained for their greatest contribution in the discriminating OPLS-DA model [variable importance in the projection (VIP) value >1.0], among which 11 metabolites were identified using both VIP values (VIP >1) and the Wilcoxon test. These metabolites potentially revealed perturbations of glycolysis and of amino acid, fatty acid, cholesterol, and nucleotide metabolism of gastric cancer patients. These results suggest that gastric cancer serum metabolic profiling has great potential in detecting this disease and helping to understand its metabolic mechanisms.

Serum metabolic profiling of human gastric cancer based on gas chromatography/mass spectrometry.

Research on molecular mechanisms of carcinogenesis plays an important role in diagnosing and treating gastric cancer. Metabolic profiling may offer the opportunity to understand the molecular mechanism of carcinogenesis and help to non-invasively identify the potential biomarkers for the early diagnosis of human gastric cancer. The aims of this study were to explore the underlying metabolic mechanisms of gastric cancer and to identify biomarkers associated with morbidity. Gas chromatography/mass spectrometry (GC/MS) was used to analyze the serum metabolites of 30 Chinese gastric cancer patients and 30 healthy controls. Diagnostic models for gastric cancer were constructed using orthogonal partial least squares discriminant analysis (OPLS-DA). Acquired metabolomic data were analyzed by the nonparametric Wilcoxon test to find serum metabolic biomarkers for gastric cancer. The OPLS-DA model showed adequate discrimination between cancer and non-cancer cohorts while the model failed to discriminate different pathological stages (I-IV) of gastric cancer patients. A total of 44 endogenous metabolites such as amino acids, organic acids, carbohydrates, fatty acids, and steroids were detected, of which 18 differential metabolites were identified with significant differences. A total of 13 variables were obtained for their greatest contribution in the discriminating OPLS-DA model [variable importance in the projection (VIP) value >1.0], among which 11 metabolites were identified using both VIP values (VIP >1) and the Wilcoxon test. These metabolites potentially revealed perturbations of glycolysis and of amino acid, fatty acid, cholesterol, and nucleotide metabolism of gastric cancer patients. These results suggest that gastric cancer serum metabolic profiling has great potential in detecting this disease and helping to understand its metabolic mechanisms.

Tissue metabolomic fingerprinting reveals metabolic disorders associated with human gastric cancer morbidity.

The principal way to improve the outcome of gastric cancer (GC) is to predict carcinogenesis and metastasis at an early stage. The aims of the present study were to test the hypothesis that distinct metabolic profiles are reflected in GC tissues and to further explore potential biomarkers for GC diagnosis. Gas chromatography/mass spectrometry (GC/MS) was utilized to analyze tissue metabolites from 30 GC patients. A diagnostic model for GC was constructed using orthogonal partial least squares discriminant analysis (OPLS-DA), and the metabolomic data were analyzed using the non-parametric Wilcoxon rank sum test to identify the metabolic tissue biomarkers for GC. Over 100 signals were routinely detected in one single total ion current (TIC) chromatogram, and the OPLS-DA model generated from the metabolic profile of the tissues adequately discriminated the GC tissues from the normal mucosae. Among the low-molecular-weight endogenous metabolites, a total of 41 compounds, such as amino acids, organic acids, carbohydrates, fatty acids and steroids, were detected, and 15 differential metabolites were identified with significant difference (p<0.05). A total of 20 variables were noted which contributed to a great extent in the discriminating OPLS-DA model (VIP value >1.0), among which 12 metabolites were identified using both VIP values (VIP >1) and the Wilcoxon test (p<0.05). In conclusion, the identification of the metabolites associated with GC morbidity potentially revealed perturbations of glycolysis, fatty acid ß-oxidation, cholesterol and amino acid metabolism. These results suggest that tissue metabolic profiles have great potential in detecting GC and may aid in understanding its underlying mechanisms.

[The effects of DNA damage induced by acetaldehyde].

The effects of DNA damage induced by the typical environmental pollutant acetaldehyde were studied with single cell gel electrophoresis (SCGE) and high performance liquid chromatography with electrochemical detection (HPLC-EC). The results showed that acetaldehyde not only could cause DNA strand breakage but also DNA-DNA, DNA-protein crosslinks of lymphocytes of human peripheral blood. The reaction of acetaldehyde with DNA in vitro was weak, but the oxidative ability was enhanced and the reaction could produce a number of 8-OHdG adducts mediated by the Fe2+. The animal experiment shows that acetaldehyde can cause the oxidative DNA damage of rat lung tissues, which suggests that acetaldehyde have the potential genotoxicity and its chemical mechanism is relative to the crosslinks and oxidation with DNA.