Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To understand the role of cyclooxygenase-2 (COX-2) in gastric cancer, we examined the abundance of COX-2, vascular endothelial growth factor-A (VEGF-A), and CD34 in 45 surgically resected human gastric cancers and paired normal gastric mucosa by immunohistochemical analysis. In addition, the message RNA (mRNA) expression of COX-2 and VEGF-A was evaluated in ten fresh surgically resected human gastric cancers and paired normal gastric mucosas using semi-quantitative reverse transcriptional polymerase chain reaction analysis. Our results confirmed an increased abundance of COX-2 and VEGF-A, and the microvessel density, which was assessed by CD34 abundance, in gastric cancer tissues compared with normal paired mucosa. Abundance of COX-2 and VEGF-A was significantly associated with tumor-node-metastasis (TNM) stage (P<0.05) and lymph node metastasis (P<0.001). In addition, abundance of VEGF-A associates with distance metastasis. A significant correlation was found between COX-2 and VEGF-A abundances (P<0.001). Both abundance of COX-2 and VEGF-A were significantly correlated with microvessel density (P<0.001, respectively). In six of ten cancerous tissues and in one of ten paired normal mucosas, the mRNA expression of COX-2 and VEGF-A was detected in the same specimen. In one other cancerous tissue, only COX-2 mRNA was detected. This study indicates that COX-2 is related to tumor angiogenesis in gastric cancer. VEGF-A might play a main role in the COX-2 angiogenic pathway.
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PMID:Increased abundance of cyclooxygenase-2 correlates with vascular endothelial growth factor-A abundance and tumor angiogenesis in gastric cancer. 1276 10

Both vascular endothelial growth factor (VEGF) and interleukin 8 (IL-8) play an important role in the progression of gastric cancer (GC). In this study, we investigated whether circulating levels of VEGF or IL-8 in drainage veins of GC patients were correlated with any clinicopathological factors. Thirty-seven patients with primary GC who underwent gastrectomy at our department between 1999 and 2002 were analyzed. Blood samples were drawn from a peripheral vein just before surgery and from a drainage vein immediately after laparotomy. Plasma VEGF levels were significantly higher than those in 10 healthy controls. There was no correlation between VEGF levels in drainage veins and any clinicopathological variable, whereas there was a significant relationship in the case of VEGF levels in peripheral veins; the levels were higher in patients with venous invasion. We found a significant relationship between IL-8 levels in drainage veins and both tumor size and lymph node metastasis, whereas no significant relationship between IL-8 levels in peripheral veins and any variable was found. There was no correlation between VEGF and IL-8 levels in drainage veins. Large tumors, deeply invasive tumors, lymph node involvement, venous invasion and high IL-8 levels in drainage veins were all significantly associated with shorter disease-free survival, although multivariate analysis revealed that lymph node involvement was the only independent prognostic factor. In conclusion, the measurement of IL-8 levels in drainage veins of GC patients may reflect production mainly by the primary lesion and is valuable as an indicator of risk for recurrent disease.
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PMID:The role of circulating IL-8 and VEGF protein in the progression of gastric cancer. 1290 1

Although gastric cancer with cyclooxygenase (COX)-2 overexpression is associated with poor prognosis, the mechanistic pathway remains unknown. We examined the associations between expressions of COX-2 and vascular endothelial growth factor (VEGF) in both gastric cancer cells and in human gastric cancer. The gastric cell line, Kato III, was transiently transfected with cox-2 expressing vector. The levels of COX-2, prostaglandin (PG) E2 and VEGF expression were measured post-transfection. Additionally, expressions of COX-2 and VEGF in human gastric cancer were determined by immunohistochemistry in archive gastrectomy specimens. Tumor angiogenesis was assessed by the microvessel density (MVD), which was determined by anti-CD34 immunostaining. Transient transfection of Kato III with cox-2 was associated with increased COX-2 expression, higher PGE2 production and upregulated VEGF expressions. Treatment with NS398, a specific COX-2 inhibitor, reduced VEGF expression in COX-2 expressing Kato III cells by 25%. Among the 67 gastric cancers examined, COX-2 overexpression was found in 45 (67%) cases whereas increased VEGF expression was detected in 46 (69%) cases. There was a significant association between COX-2 and VEGF expressions in gastric cancer (r=0.25, p=0.041). Additionally, tumor MVD was associated with both COX-2 (r=0.32, p=0.008) and VEGF (r=0.39, p=0.001) expressions. Our results showed that overexpression of COX-2 in both gastric cells and primary gastric cancer is associated with upregulation of VEGF and angiogenesis. Future studies should evaluate the potential anti-angiogenic effect of COX-2 inhibitors on human gastric cancer.
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PMID:Cyclooxygenase-2 upregulates vascular endothelial growth factor expression and angiogenesis in human gastric carcinoma. 1453 71

A cell colony (IM95m) that produces hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and interleukin-8 (IL-8) was cloned from gastric cancer cells (IM95 cell line). In culture medium, the highest levels of HGF, VEGF, and IL-8 were about 1.1, 0.9, and 0.17 ng/ml culture medium at 3 d from 10(5) cells. IM95m may be useful in elucidating the role of tumor cells in angiogenesis.
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PMID:Cloning of a cancer cell-producing hepatocyte growth factor, vascular endothelial growth factor, and interleukin-8 from gastric cancer cells. 1460 62

This study was undertaken to determine the value of tumour microvessel density (MVD) and the expression of p53 and vascular endothelial growth factor (VEGF) as prognostic markers in patients with gastric cancer operated on for cure. In all, 156 patients with curatively resected gastric cancer constituted the basis of this blinded retrospective evaluation. Patients were treated with either surgery alone (n=53) or surgery plus adjuvant chemotherapy (n=103). Tumour MVD, p53 expression, and VEGF expression were assayed using immunohistochemical techniques. After a mean follow-up of 43 months, 64 (41%) patients had died and 55 (35%) patients developed tumour recurrence. Positive correlations between MVD and both p53 (P=0.005) and VEGF (P=0.005) expression were observed. Both MVD >/=100 (P=0.05) and positive VEGF expression (P<0.02) were associated with shorter disease-free survival, and positive VEGF expression (P=0.01) was also associated with shorter overall survival. Multivariate analysis confirmed that, in addition to the pathological tumour stage, lymph node ratio, the extent of lymphadenectomy and perineural invasion, p53 expression, and VEGF expression were independently associated with both disease-free survival (P<0.0005 and 0.02, respectively) and overall survival (P<0.02 and 0.01, respectively). Finally, patients whose tumours did not show p53 expression had a survival benefit compared to those expressing p53 when treated with adjuvant chemotherapy (P=0.01). This investigation demonstrates that p53 expression and VEGF expression are independent prognostic factors for both disease-free survival and overall survival in patients with curatively resected gastric cancer, and that p53 status may also influence response to chemotherapy.
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PMID:p53 and VEGF expression are independent predictors of tumour recurrence and survival following curative resection of gastric cancer. 1471 Feb 31

In vitro studies suggest that cyclooxygenase-2 (COX-2) induces angiogenesis by stimulating angiogenic growth factors while inhibiting apoptosis in cancer cell lines. A series of 107 gastric adenocarcinoma cases that had undergone gastrectomy was studied to determine the correlation between COX-2 expression, angiogenesis, and apoptosis in human gastric cancer tissue. COX-2, vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and Bcl-2 were stained by single and dual immunoassaying methods. Microvessel density was determined by immunostaining for CD34. Apoptosis was evaluated with the TUNEL assay. COX-2 expression was positive exclusively in cancer cells in 46 cases (43%). COX-2 expression significantly correlated with VEGF and PDGF expression. Dual staining for COX-2 and VEGF showed that colocalization of these proteins was most frequent at the advancing edge of cancer cells. Microvessel density was higher in COX-2-and VEGF-positive cases than in COX-2- and VEGF-negative cases. In addition, COX-2 expression correlated with Bcl-2 expression. The apoptotic index was lower in COX-2-positive cancer cells than in COX-2-negative cases. Multivariate analysis revealed that coexpression of COX-2 and VEGF, age, lymph node status, and serosal invasion were independent prognostic factors for overall survival in gastric cancer patients. Therefore, these data suggest that COX-2 contributes to gastric cancer development by promoting angiogenesis and inhibiting apoptosis.
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PMID:Cyclooxygenase-2 expression correlates with angiogenesis and apoptosis in gastric cancer tissue. 1511 31

The biological and clinical behaviors of cancer are affected by multiple molecular pathways that are under the control of transcription factors. Improved understanding of how transcription factors affect cancer biology may lead to improved ability to predict clinical outcome and discovery of novel therapeutic strategies. We evaluated the relationship between Sp1 and vascular endothelial growth factor (VEGF) expression, as well as their effect on survival in 86 cases of resected human gastric cancer. The degree of VEGF expression correlated highly with Sp1 expression (P < 0.01). Patients with high Sp1 expression were 98 times more likely to have high VEGF expression compared with those with negative Sp1 expression. Clinically, negative or weak Sp1 expression was associated with early stage (IA) in gastric cancer. Strong Sp1 expression was more frequently observed among patients with stage IB-IV disease (P = 0.035). Similarly, whereas strong Sp1 expression was uncommonly observed among patients with N0 or N1 disease (19 and 16%), N2/N3 gastric cancer was associated with strong Sp1 expression (48%; P = 0.034). Strong Sp1 expression was also associated with inferior survival. The median survival duration in patients who had a tumor with a negative, weak, and strong Sp1 expression was 44, 38, and 8 months (P = 0.0075), respectively, whereas patients with strong VEGF expression had a shorter survival duration; the difference was not statistically significant. When Sp1 and VEGF expression, stage, completeness of resection, histology, and patient age were entered in a Cox proportional hazards model, strong Sp1 expression (P = 0.021) and an advanced disease stage (P < 0.001) were independently prognostic of poor survival. Given the importance of Sp1 in the expression of VEGF, our data suggest that dysregulated Sp1 expression and activation play important roles in VEGF overexpression and, thus, gastric cancer development and progression.
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PMID:Association between expression of transcription factor Sp1 and increased vascular endothelial growth factor expression, advanced stage, and poor survival in patients with resected gastric cancer. 1521 47

Monoclonal antibodies (mAbs) against growth factors or their receptors have been revealed to be effective therapeutic agents for solid tumors. Trastuzumab (humanized anti-HER2 mAb) is the first mAb approved for the treatment of a solid tumor, metastatic breast cancer. Large-scale phase III clinical trials are now ongoing to further evaluate the additive effects on chemotherapy and the efficacy as a maintenance monotherapy. Another anti-HER2 mAb CH401 that we developed also seems to have good potential. This chimeric mAb completely suppressed the growth of established human tumor xenografts in SCID mice after a single injection. Furthermore, CH401 characteristically showed much stronger induction of apoptosis in HER2-overexpressing gastric cancer cells compared to trastuzumab. Additional targets now being intensively evaluated are epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF). Both cetuximab (chimeric anti-EGFR mAb) and bevacizumab (humanized anti-VEGF mAb) have recently been shown to be of clinical value for metastatic colorectal cancer. Anti-idiotype mAbs are unique as active immunotherapeutic agents, and survival benefits have been observed in clinical trials for solid tumors.
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PMID:Monoclonal antibodies as effective therapeutic agents for solid tumors. 1529 22

Placenta growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family of proangiogenic factors and its overexpression has been linked to pathological angiogenesis. We studied the relationship between the expression of PlGF and VEGF in human gastric cancer tissues and microvessel density (MVD), as well as clinical outcome in 79 patients with gastric cancer by using an enzyme immunoassay for PlGF and VEGF expression levels in gastric cancers and surrounding non-cancerous mucosa. PlGF protein levels were significantly higher in tumor than in the corresponding non-tumorous mucosa (median value 48.5 vs 9.8 pg/mg, P < 0.001). In contrast, VEGF protein levels were not (66.7 vs 80.7 pg/mg, P = 0.522). VEGF expression level was not significantly correlated with MVD, patient survival, and clinicopathological factors except Lauren classification in this study. PlGF may be an important angiogenic factor in human gastric cancer, and PlGF expression level was significantly correlated with serosal invasion, positive lymph node metastases, tumor stages, and patient survival.
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PMID:The significance of placenta growth factor in angiogenesis and clinical outcome of human gastric cancer. 1531 86

Early studies revealed that cigarette smoke promotes gastric cancer growth through the induction of cyclooxygenase-2 (COX-2). Nicotine, one of the active ingredients in cigarette smoke, has detrimental effects in the stomach. To date, there is no direct evidence to validate the effect of nicotine on gastric tumor growth and its carcinogenic mechanism(s). We therefore investigated whether nicotine could promote tumor growth and neovascularization in vivo, and the biological mechanism(s) in connection with the signaling cascade involving COX-2 and extracellular signal-regulated protein kinase (ERK). Athymic nude mice, with gastric cancer cells (AGS) orthotopically implanted into the gastric wall, treated with nicotine (50 or 200 microg/ml) in their drinking water for 3 months developed larger tumor areas than mice in the control group. Nicotine further increased proliferating cellular nuclear antigen (PCNA) staining and microvessel density by 70 and 30%, respectively, with concomitant activation of ERK phosphorylation, COX-2 and vascular endothelial growth factor (VEGF) expression in the tumors. Intraperitoneal administration of a selective COX-2 inhibitor (SC-236, 2 mg/kg) prevented the nicotine-induced tumor growth and neovascularization dose-dependently. Consistent with our animal model, an in vitro study also demonstrated that incubation with nicotine (50-200 microg/ml) for 5 h stimulated cell proliferation dose-dependently and increased COX-2 expression, prostaglandin E(2) (PGE(2)) and VEGF release, as well as activation of ERK phosphorylation. Pre-treatment with specific mitogen-activated protein kinase kinase (MEK) inhibitors (U0126 or PD98059) attenuated COX-2 expression and subsequent PGE(2) release by nicotine. Furthermore, the stimulatory action of nicotine on cancer cell growth and angiogenic factor VEGF production was suppressed by inhibitors of MEK (U0126) and COX-2 (SC-236). These findings reveal a direct promoting action of nicotine on the growth of gastric tumor and neovascularization through sequential activation of the ERK/COX-2/VEGF signaling pathway, which can be targeted for chemoprevention of gastric cancer, particularly in cigarette smokers.
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PMID:Nicotine promotes gastric tumor growth and neovascularization by activating extracellular signal-regulated kinase and cyclooxygenase-2. 1531 99


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