endothelin-1 and Stomach-Neoplasms

Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is one of the four subtypes of gastric carcinoma and its unique clinicopathological mechanism is unclear. Herein, the expression of endothelin-1 (ET-1) in EBVaGC was lower than of Epstein-Barr virus-negative gastric carcinoma (EBVnGC) and associated with a low frequency of lymph node metastasis of EBVaGC. Functional studies showed that the activation of ET-1/endothelin receptor type A (ETAR) axis could promote cell growth, migration, and antiapoptosis. The expression of the ET-1 gene was unrelated to methylation of its promoter region and miRNAs (-1, -125a, -125b). After being treated with MEK1/2 inhibitor (PD0325901), the inactivation of ERK1/2 pathway resulted in downregulation of ET-1 and forkhead box O1 (FOXO1) expression. Further, FOXO1 knockdown decreased the ET-1 expression. These findings indicated that ET-1 could be involved in development of gastric cancer and EBV could suppress the expression of ET-1 via the regulation of the transcription factor FOXO1 through the MAPK/ERK pathway.

Topics: Carcinogenesis; Carcinoma; Endothelin-1; Epstein-Barr Virus Infections; Forkhead Box Protein O1; Herpesvirus 4, Human; Humans; MAP Kinase Signaling System; Stomach Neoplasms

Endothelin-1 (ET-1) is a peptide overexpressed in gastric cancer (GC) and linked to carcinogenesis and resistance to chemotherapy. Applying microRNAs (miRNAs/miRs) to downregulate ET-1 and reverse resistance to commonly used chemotherapy drugs such as 5-fluorouracil (5-FU) is practical.. The current study sought to evaluate the miR-648 expression in GC and any plausibility of its replacement, either with or without the combination of chemo agents to downregulate ET-1 expression through interaction with its target gene. To this end, miR-648 and ET-1 expression levels were assessed in GC tissues and adjacent non-tumor tissues driven from 65 patients who had already undergone surgery, fifteen of which had received 5-FU before surgery. The impact of miR-648 and chemo agents on ET-1 expression was measured using qPCR and Western blotting. Further, an MTT assay was conducted to assess its association with cell viability. Ultimately, the association of miR-648 and ET-1 with clinicopathological characteristics was evaluated.. The current study revealed that miR-648 was considerably down-regulated, while ET-1 was substantially up-regulated in patients with GC. The 5-FU caused a significant increase in miR-648 and reduced ET-1 expression. It was also determined that overexpression of miR-648 suppressed ET-1 production, notably when combined with 5-FU, leading to survival reduction. These results further showed that miR-648 replacement could sensitize chemoresistant GC cells. Besides, a significant association between ET-1 and miR-648 with clinicopathological features was discovered CONCLUSIONS: miR-648 replacement may serve as a potential oncosuppressive therapeutic approach that warrants further investigation to translate into an effective GC treatment.

Topics: Cell Line, Tumor; Cell Proliferation; Drug Resistance, Neoplasm; Endothelin-1; Fluorouracil; Gene Expression Regulation, Neoplastic; Humans; MicroRNAs; Stomach Neoplasms

We recently reported that miR-1 was one of the most significantly downregulated microRNAs in gastric cancer (GC) patients from The Cancer Genome Atlas microRNA sequencing data. Here we aim to elucidate the role of miR-1 in gastric carcinogenesis.. We measured miR-1 expression in human GC cell lines and 90 paired primary GC samples, and analyzed the association of its status with clinicopathological features. The effect of miR-1 on GC cells was evaluated by proliferation and migration assay. To identify the target genes of miR-1, bioinformatic analysis and protein array analysis were performed. Moreover, the regulation mechanism of miR-1 with regard to these predicted targets was investigated by quantitative PCR (qPCR), Western blot, ELISA, and endothelial cell tube formation. The putative binding site of miR-1 on target genes was assessed by a reporter assay.. Expression of miR-1 was obviously decreased in GC cell lines and primary tissues. Patients with low miR-1 expression had significantly shorter overall survival compared with those with high miR-1 expression (P = 0.0027). Overexpression of miR-1 in GC cells inhibited proliferation, migration, and tube formation of endothelial cells by suppressing expression of vascular endothelial growth factor A (VEGF-A) and endothelin 1 (EDN1). Conversely, inhibition of miR-1 with use of antago-miR-1 caused an increase in expression of VEGF-A and EDN1 in nonmalignant GC cells or low-malignancy GC cells.. MiR-1 acts as a tumor suppressor by inhibiting angiogenesis-related growth factors in human gastric cancer. Downregulated miR-1 not only promotes cellular proliferation and migration of GC cells, but may activates proangiogenesis signaling and stimulates the proliferation and migration of endothelial cells, indicating the possibility of new strategies for GC therapy.

Topics: Adenocarcinoma; Adult; Aged; Endothelin-1; Female; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Humans; Male; MicroRNAs; Middle Aged; Neovascularization, Pathologic; Stomach Neoplasms; Vascular Endothelial Growth Factor A

Endothelin-1 (ET-1) is a small 21-amino acid peptide that is known to exert diverse biological effects on a wide variety of tissues and cell types through its own receptors. The ET-1-ETRA axis is frequently dysfunctional in numerous types of carcinomas, and contributes to the promotion of cell growth and migration. microRNAs (miRNAs) are small non-coding RNAs that play a critical role in carcinogenesis through mRNA degradation or the translational inhibition of cancer-associated protein-coding genes. However, the role of ET-1 and the relationship between ET-1 and miRNAs in gastric cancer remain unknown. Results of the analysis of the database of The Cancer Genome Atlas (TCGA) revealed that ET-1 is significantly overexpressed in gastric cancer cells when compared with its expression in adjacent normal cells. Exogenous ET-1 significantly enhanced gastric cancer cell proliferation, implying that ET-1 plays an oncogenic role in gastric cancer carcinogenesis. Using a luciferase reporter assay we showed that 18 miRNA candidates had a significant silencing effect on ET-1 expression by up to 20% in HEK293T cells. Among them, 5 miRNAs (miR-1, miR-101, miR-125A, miR-144 and let-7c) were shown to be involved in ET-1 silencing through post-transcriptional modulation in gastric cancer. Our data also revealed that DNA hypermethylation contributes to the silenced miR-1 expression in gastric cancer cells. The ectopic expression of miR-1 significantly inhibited AGS cell proliferation by suppressing ET-1 expression. Overall, our study revealed that ET-1 overexpression may be due to DNA hypermethylation resulting in the silencing of miR-1 expression in gastric cancer cells. In addition, we identified several miRNAs as potential modulators for ET-1 in gastric cancer, which may be used as targets for gastric cancer therapy.

Topics: 3' Untranslated Regions; Cell Line, Tumor; Cell Proliferation; CpG Islands; DNA Methylation; Endothelin-1; Gene Expression Regulation, Neoplastic; Humans; MicroRNAs; RNA Interference; Stomach Neoplasms

Endothelin, a potent vasoconstrictor peptide, is involved in mitogenesis modulation, apoptosis, angiogenesis, tumor invasion and metastases. Big endothelin-1 (Big ET-1), the stable precursor of endothelin-1, is regarded as a marker of tumor progression and prognosis. This study was to detect the expression of Big ET-1 in gastric cancer patients, and explore its correlations to progression and prognosis of gastric cancer.. The plasma levels of Big ET-1 in 118 gastric cancer patients and 20 healthy subjects were detected by enzyme-linked immunosorbent assay (ELISA). The expression of Big ET-1 in primary tumor and para-cancerous gastric tissues of the 118 patients was detected by immunohistochemistry.. The plasma level of Big ET-1 was significantly higher in patients with advanced gastric cancer than in patients with early stage gastric cancer and healthy subjects [(5.78+/-1.85) ng/L vs. (3.13+/-1.72) ng/L and (2.46+/-0.59) ng/L, P=0.026, P=0.008]. The plasma level of Big ET-1 was significantly higher in patients with lymph node metastases than in those without [(6.13+/-2.34) ng/L vs. (4.25+/-1.65) ng/L, P=0.006], and significantly higher in stage II, III, IV patients than in stage I patients. During follow-up, patients with high plasma levels of Big ET-1 had higher recurrence rate and lower 2-year survival rate as compared with those with low plasma levels of Big ET-1 (84.6% vs. 60.9%, P=0.034; 38.5% vs. 56.5%,P=0.017). The positive rate of Big ET-1 was significantly higher in stage II,III and IV patients than in stage I patients.. The plasma level of Big ET-1 may play a vital role in the development, invasion and metastasis of gastric cancer, and may be a predictor of tumor disease severity and prognosis.

Topics: Adult; Aged; Biomarkers, Tumor; Endothelin-1; Female; Follow-Up Studies; Gastric Mucosa; Humans; Immunohistochemistry; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Recurrence, Local; Neoplasm Staging; Preoperative Period; Prognosis; Stomach Neoplasms; Survival Rate

To investigate the plasma Big endothelin-1 levels in patients with gastric carcinoma before and after radical gastrectomy, and explore its clinical significance.. One hundred and six patients with gastric carcinoma and 20 controls were enrolled. The Big ET-1 plasma levels were examined by enzyme-linked immuno absorbent assay before and on the 1st, 3rd, and 10th day after curative surgery, and then were tested every 3 months in the patients with advanced gastric cancer.. All patients, except those with stage I gastric cancer, had significantly higher mean plasma Big ET-1 levels compared with normal controls (P=0.000). Higher plasma Big ET-1 levels were associated with lymph node metastasis (P=0.020) and serosal infiltration (P=0.035). The plasma Big Endothelin-1 levels were markedly increased on the first post-operative day (1st POD) in all patients,but decreased on the 3rd POD with no significant difference compared to the preoperative levels. On the 10th POD, the patients with stage I and II gastric cancer showed marked reduction in plasma Big ET-1 levels (P=0.010 and P=0.000, respectively), whereas no significant difference was observed in stage III and IV patients. During the follow-up, the plasma Big ET-1 levels just before recurrence in stage II patients were significantly higher compared with the levels on the 10th POD (P=0.011).. Plasma Big ET-1 might be a reliable marker to determine the severity of gastric carcinoma. Monitoring plasma Big ET-1 levels after curative resection in stage II gastric cancer patients is valuable to predict recurrence.

Topics: Adult; Aged; Case-Control Studies; Endothelin-1; Female; Follow-Up Studies; Gastrectomy; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Neoplasm Staging; Stomach Neoplasms

Endothelins have been implicated in gastric mucosal damage in a variety of animal models. Furthermore, clinical reports also show elevated gastric mucosal endothelin-1 levels in patients suffering from peptic ulcer diseases. We have demonstrated, first, the presence of immunoreactive endothelin (IR-ET) in human saliva. We also show that endothelins are rather stable in human saliva. The present study was undertaken to determine whether patients with endoscopically proven upper gastrointestinal diseases have a salivary excess of IR-ET, compared with patients with a normal esophagogastroduodenoscopy. Saliva was collected from fasting subjects prior to esophagogastroduodenoscopy. The levels of IR-ET were measured by the radioimmunoassay method. The salivary concentrations of IR-ET in the studied subjects were as follows: 8.9 +/- 1.0 fmol/mL (mean +/- standard error of the mean) for patients with gastric ulcers (n = 18); 7.3 +/- 1.0 fmol/mL for patients with duodenal ulcers (n = 22); and 6.8 +/- 0.6 fmol/mL for patients with gastritis (n = 28). These values are all higher than that of normal subjects (4.4 +/- 0.5 fmol/mL, n = 20; P < 0.001, P < 0.01, and P < 0.05, respectively). No significant differences in salivary IR-ET were noted between patients with a normal esophagogastroduodenoscopy and patients with esophagitis (3.8 +/- 0.7 fmol/mL, n = 4) or gastric cancer (5.3 +/- 1.4 fmol/mL, n = 4). There were no significant differences in the salivary IR-ET levels between males and females. However, the salivary IR-ET levels in the smokers (8.0 +/- 0.6 fmol/mL, n = 38) were significantly higher (P < 0.01) than those of the non-smokers (6.0 +/- 0.4 fmol/mL, n = 58). There was no correlation of IR-ET levels with age. Our findings suggest that salivary endothelin may have a contributing role in certain gastroduodenal diseases.

Topics: Asian People; Duodenal Ulcer; Endoscopy, Digestive System; Endothelin-1; Endothelin-2; Endothelin-3; Esophagitis; Female; Gastritis; Gastrointestinal Diseases; Humans; Male; Radioimmunoassay; Saliva; Smoking; Stomach Neoplasms; Stomach Ulcer; Taiwan; Up-Regulation; Upper Gastrointestinal Tract

To investigate the involvement of vasoactive agents, endothelin (ET)-1, and atrial natriuretic peptide (ANP), and the responses of cytokines in patients undergoing total gastrectomy.. Prospective study.. University hospital, Japan.. 20 patients with advanced gastric cancer who had undergone total gastrectomy with lymph node dissection.. Serum or plasma samples collected on the day before the operation, at the time of skin closure, and on postoperative days 1, 3, 5, and 7.. Concentrations of acute phase reactants, cytokines (interleukin (IL)-1, tumour necrosis factor (TNF) and interleukin (IL)-6), and vasoactive agents (ET-1 and ANP).. There were significant increases in concentrations of IL-6 and acute phase reactants postoperatively. ET-1 and ANP concentrations did not change significantly.. There was no correlation between concentrations of the vasoactive agents ET-1 and ANP, and those of acute phase reactants or cytokines in serum or plasma in patients undergoing total gastrectomy.

Topics: Acute-Phase Proteins; Atrial Natriuretic Factor; C-Reactive Protein; Cytokines; Endothelin-1; Female; Gastrectomy; Humans; Interleukin-1; Interleukin-6; Leukocyte Elastase; Male; Middle Aged; Prospective Studies; Stomach Neoplasms; Tumor Necrosis Factor-alpha