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 clarify the prognostic value of tumor cell proliferation [proliferating cell nuclear antigen (PCNA)-positive rate assessed by anti-PCNA immunostaining] and intratumor microvessel density (/0.74 mm2, assessed by anti-CD34 immunostaining) in gastric cancer, 192 advanced gastric cancer patients who underwent curative surgery were investigated. Multivariate analysis showed that the following variables were significantly related to prognosis: age (P=0.029), depth of invasion (P=0.005), lymph node metastasis (P=0.006), lymphatic invasion (P=0.038), venous invasion (P=0.0005), PCNA-positive rate (P=0.049) and intratumor microvessel density (P=0. 011). In conclusion, tumor cell proliferation and intratumor microvessel density were independent prognostic factors in patients with advanced gastric cancer undergoing curative surgery.
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PMID:Prognostic value of tumor cell proliferation and intratumor microvessel density in advanced gastric cancer treated with curative surgery. 966 19

Although recent studies have demonstrated that cyclooxygenase (COX)-2 is overexpressed in various cancers including gastric cancer, the mechanisms underlying the contribution of COX-2 to tumorigenesis and tumor promotion still remain unclear. To determine the role of COX-2, we investigated the COX-2 expression, the prostaglandin (PG) levels, and the microvessel density in 42 patients with primary gastric adenocarcinoma. COX-2 protein was over-expressed in 31 (74%) of 42 gastric cancers based on an immunoblot analysis. The intensity of COX-2 expression was found to significantly correlate with lymph node involvement. The COX-2 overexpressed cases showed significantly elevated levels of prostaglandin E2 (PGE2) in cancer tissues in comparison with the normal gastric mucosa by an immunoassay (201 +/- 90 versus 161 +/- 57 ng/mg protein; P < 0.05). However, the COX-2 overexpression was not related to the levels of thromboxane B2 and 6-keto-prostaglandin F1alpha. The density of microvessel immunostained with CD34 was significantly higher in patients demonstrating COX-2 overexpression than in those without such expression (63 +/-21 versus 45 +/- 17/200 x; P < 0.01). Our data thus suggested COX-2 overexpression to be associated with increased PGE2 biosynthesis and angiogenesis in gastric cancer, which indicates that COX-2 may play a role in the development of gastric cancer.
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PMID:Cyclooxygenase-2 expression is related to prostaglandin biosynthesis and angiogenesis in human gastric cancer. 1065 41

Gastric cancer (GC) continues to be a highly aggressive malignancy with poor prognosis and low survival rates. The survival of patients with GC depends mainly on the stage of the disease, with early GC having a 5 year survival of 90-100% and advanced tumors a 5 year survival of 15-25%. The role of other prognostic factors in these tumors is still under investigation. 28 gastric dysplasia, 45 Early GC and 98 Advanced Gastric Cancers were evaluated for expression of the oncogenes p53, c-ErbB2, c-myc and the EGFr in paraffin-embedded material utilizing Avidin-Biotin immunohistochemistry techniques. In 34 cases of GC microvessel density (MVD) was determined in CD34 stained sections. Statistical correlations with stage, histologic type, differentiation degree, location, size, ploidy patterns and overall survival were done. The Mantel-Cox test was performed to evaluate which factors had an independent prognostic value. Both, tumor angiogenesis and p53 protein expression were statistically associated (95% confidence intervals) with overall survival in patients with GC. p53 protein expression was also correlated with cardial location, nodal involvement and tumor stage. c-ErbB2 may recognize a group of highly aggressive well differentiated adenocarcinomas with worse prognosis. c-myc was also significantly enhanced in well differentiated tumors. EGFr showed no significant associations. Mantel-Cox was performed to compare the prognostic value of tumor stage, p53 protein expression and tumor angiogenesis. Tumor angiogenesis was the most important prognostic indicator to predict overall survival in our series. p53 expression was not independent and did not provide additional prognostic information to tumor stage. Our study suggests that angiogenesis as demonstrated by microvessel counts in CD34 stained sections is a significantly important prognostic factor for predicting survival in gastric cancer.
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PMID:Comparative study of tumor angiogenesis and immunohistochemistry for p53, c-ErbB2, c-myc and EGFr as prognostic factors in gastric cancer. 1080 64

The formation of new blood vessels is essential for tumor growth and progression. Until today there are only few studies of the immunohistochemical assessment of angiogenesis in gastric cancer by the evaluation of the expression of CD34 antigen. The aim of this study was to analyze the relationship between microvessel density (MVD) expressed as the mean count of CD34 immunostained vessels and clinicopathologic features of gastric tumors (the histological type according to the Lauren classification, tumor grade G; presence of lymph node metastases N; depth of tumor invasion; stage of disease (UICC-AJCC 1988 1992), p53 expression, tumor cell proliferative activity described as the Ki67 labelling index and apoptotic index of tumor cells TUNEL method). We assessed formalin-fixed, paraffin-embedded tissue samples obtained during potentially radical gastrectomy from 58 patients with primary gastric adenocarcinoma. The representative tissue blocks from each tumor were used for the immunohistochemical assay and examined by two pathologists independently. MVD was counted in five tumor areas of the most intensive neovascularization (x 200 field by light microscopy) and the mean counts were recorded. The mean MVD (CD34 expression value+/-SD) in this study was 43,15+/-19,8 per x 200 field. The study demonstrated the statistically significant correlation between MVD and two main histological parameters: tumor grading (p < 0.001) and tumor histological type according to Lauren s classification (p<0.05). In well and moderately differentiated tumors (G1/2) MVD was significantly lower in comparison to the group of poorly differentiated cancer G3 (mean value: 31,62 vs. 49,89). MVD was higher in diffuse type of gastric cancer comparing to intestinal type (50.05+/-19,03 vs. 39.17+/-20,09). However, the authors failed to find a significant correlation between MVD and other investigated histopathological features in malignant gastric tumors. The close relationship between CD34 immunostaining, gastric cancer tumor vascularity and main histological parameters was shown in this study. It can be stated that analysis of expression of angiogenesis in gastric cancer may be helpful for better estimation of hematogenous recurrence and the selection of the group of patients for adjuvant antiangiogenic treatment.
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PMID:Expression of CD34 in gastric cancer and its correlation with histology, stage, proliferation activity, p53 expression and apoptotic index. 1145 76

The aim of this study was to investigate whether angiogenic factors influence the occurrence of spontaneous apoptosis in advanced gastric cancer. The apoptotic indices (AIs) of 97 tumors from 97 patients with advanced gastric cancer (pT3, pN0, pM0, Stage II) were analyzed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling (TUNEL) method. Intratumoral microvessel densities (IMVDs) of tumors stained with anti-CD34 monoclonal antibody were quantified under x 200 magnification using computer-assisted image analysis. The expressions of angiogenic factors, such as vascular endothelial growth factor (VEGF), thymidine phosphorylase (dThdPase), transforming growth factor-alpha (TGF-alpha), and p53 were analyzed immunohistochemically and compared with IMVDs and AIs. The mean IMVD of the 97 tumors was 365/mm2 (range 147-990/mm2). The mean AI of tumors was 2.1% (range 0-11.3%). A significant inverse correlation between the AIs and the IMVDs was shown (p = -0.278, P = 0.0064). The mean IMVDs of tumors with high expressions of dThdPase, TGF-alpha, or p53 were significantly higher than those of tumors with low expressions of these factors. The mean AI of tumors with high expressions of dThdPase was significantly lower than that of tumors with low expressions of dThdPase (P = 0.023). However, no significant correlations were detected between AIs and the expression levels of VEGF, TGF-alpha, or p53. In gastric cancer, dThdPase may play an important role in tumor progression by increasing microvessels and by suppressing apoptosis of cancer cells.
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PMID:Correlation between spontaneous apoptosis and the expression of angiogenic factors in advanced gastric adenocarcinoma. 1148 84

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

Angiogenesis is a key prerequisite for the successful establishment, growth, and dissemination of tumors. Vascular endothelial growth factor (VEGF) has a potent angiogenic activity and cyclooxygenase-2 (COX-2) promotes angiogenesis by modulated production of angiogenic factors including VEGF. The current study was designed to investigate the possible roles of COX-2 and VEGF in gastric cancer angiogenesis. In this study, we conducted an immunohistochemical investigation of COX-2 and VEGF expression in 97 patients with gastric cancer. To assess tumor angiogenesis, microvessel density (MVD) was determined by CD34 immunohistochemical staining. Expression of COX-2 and VEGF in gastric cancer tissues, was demonstrated in 63.9% and 75.3% of cases, respectively. The expression of COX-2 correlated significantly with VEGF expression. High MVD was significantly associated with depth of tumor invasion and poor survival. The mean MVD value of VEGF positive tumors was 79.8 +/- 32.0 and significantly higher than that of VEGF negative tumors. The mean MVD value of COX-2 positive tumors was 77.9 +/- 29.9 and not significantly higher than that of COX-2 negative tumor. The mean value of MVD in tumors positive for both COX-2 and VEGF was significantly higher than that in tumors negative for both. However, there was no correlation between COX-2 or VEGF expression and various clinicopathological features including patient survival. These results suggest that COX-2 may play an important role in carcinogenesis by stimulating tumor angiogenesis in concert with VEGF in human gastric cancer.
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PMID:Cyclooxygenase-2 overexpression correlates with vascular endothelial growth factor expression and tumor angiogenesis in gastric cancer. 1281 Dec

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

The extracellular matrix protein 1 (ECM1) is a secreted protein that has been implicated with cell proliferation, angiogenesis and differentiation. In the present study, we used immunohistochemical staining to examine the expression of ECM1 in a panel of human tumors and found that it was closely correlated with some types of tumors including: invasive breast ductal carcinoma (83%), esophageal squamous carcinoma (73%), gastric cancer (88%) and colorectal cancer (78%). Significantly, ECM1expression was correlated with the metastatic properties of the tumors. Primary breast cancers that had formed metastases were 76% positive while those that had not metastasized were only 33% positive. ECM1 expression was also correlated with PCNA a marker for proliferation, but not with CD34, a marker for endothelial cells. These results indicate that ECM1 tends to be preferentially expressed by metastatic epithelial tumors.
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PMID:Extracellular matrix protein 1 (ECM1) is over-expressed in malignant epithelial tumors. 1455 Sep 53

The present study was undertaken to clarify the histochemical and ultrastructural properties and the three-dimensional distribution of the smooth muscle cells (SMCs) located in the lamina propria (LP) of the human gastric mucosa. Standard paraffin sections obtained from stomachs surgically resected for gastric cancer were immunostained for alpha-smooth muscle actin (alpha-SMA), vimentin, desmin, laminin, and type IV collagen. In addition, 100-microm-thick sections were fluorostained for alpha-SMA and CD34, while three-dimensional images were prepared by confocal laser scanning microscope. Ultrastructural studies were carried out using normal gastric biopsy specimens. The results indicated that SMCs in the LP differed between the upper and lower regions, SMCs in the lower LP being fairly typical SMCs, whereas those in the upper LP had apparently lost reactivity for desmin but gained that for vimentin. The basal lamina became sparser, but a fibronexus was occasionally seen in SMCs in the upper LP. Three-dimensional images revealed bundles of SMCs in the upper LP encircling several foveolae to form acinus-like structures and, in the upper LP, SMCs branching into fine fibrils with a brush-like (corpus) or besom-like (i.e., a twiggy "witch's broom") appearance (antrum).
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PMID:Histochemical, ultrastructural, and three-dimensional observation of smooth muscle cells in human gastric mucosa. 1496 14


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