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)

Prognostic criteria of the patients with gastric cancer are of critical importance in their management and follow-up. Angiogenesis is essential for the growth and metastasis of solid tumors. Tumor angiogenesis is a multi-step interactive process, and vascular endothelial growth factor (VEGF) and its receptors have a major role in tumor angiogenesis. Thus, we investigated the effects of VEGF and VEGF receptor-2 (VEGFR-2, KDR) on survival in patients with gastric cancer. We analyzed 51 patients who had undergone total or subtotal gastric resection. The patients were divided into two subgroups according to their VEGF and VEGFR-2 (KDR) expression in resected specimens. There was no significant difference between sex, surgical method, lymph node metastasis, serosal invasion, hematogenous metastasis, chemotherapy status of the two subgroups. Mean follow-up time was 24.22 +/- 15.38 months. We found the survival rates of the patients with VEGF positive tumors to be significantly shorter than those of the patients with VEGF negative tumors. There was no significant difference between the survival rates of VEGFR-2 (KDR) positive and negative patients. It was established that the presence of VEGF expression was significantly associated with the short survival rates in patients with gastric cancer. Analysis of VEGF expression in resected specimens may provide additional guidance in determining the prognosis of such patients. If more extensive studies confirm the significance of VEGF and its receptors in gastric cancer, new therapeutic approaches targeting VEGF and its receptors may be considered in gastric cancer management.
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PMID:The effects of VEGF and VEGFR-2 on survival in patients with gastric cancer. 1676 23

Previous studies by our laboratory indicated that zinc ribbon domain-containing 1 (ZNRD1) suppressed the growth of gastric cancer cells with a G(1) cell cycle arrest. However, the precise molecular mechanism underlying the growth-inhibitory effect of ZNRD1 remained fragmentary. In the present study, we have demonstrated that ZNRD1 could significantly inhibit the in vitro and in vivo growth of gastric cell line MKN28. Human cDNA microarray, reverse transcription-polymerase chain reaction and western blot analyses were used to identify differentially expressed cell cycle-related genes in MKN28 cells over-expressing ZNRD1. ZNRD1-induced growth suppression was found at least partially to regulate various proteins and signaling pathways controlling G(1) to S progression, including inhibition of cyclin D1 and CDK4, up-regulation of p21(CIP1/WAF1) and p27(Kip1) and acceleration of pRb dephosphorylation. Furthermore, ZNRD1 significantly inhibited the transcriptional activity of cyclin D1. p27(Kip1) might play a pivotal role in ZNRD1-induced cell cycle arrest because the p27(Kip1) anti-sense could block the cytostatic effects of ZNRD1. Moreover, ZNRD1 suppressed Skp2 expression via an increase in the protein instability, and induced significant decrease in cyclin E-CDK2 kinase activity. In addition, ZNRD1 could reduce tumor microvessel densities through inhibition of VEGF. Taken together, these results suggested that ZNRD1 might inhibit cell growth by targeting cell cycle-related genes and reducing tumor angiogenesis.
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PMID:Mechanisms of growth arrest by zinc ribbon domain-containing 1 in gastric cancer cells. 1738 17

Osteopontin (OPN) plays an important role in tumorigenesis, tumor invasion, and metastasis in many types of cancers, including gastric cancer. Recently, much interest has been focused on the role of OPN in tumor angiogenesis. Our previous studies have shown that OPN is overexpressed, and associated with mean microvessel density in, the tissue samples of patients with gastric cancer. In the present study, we aimed to further determine and provide evidence for the role of OPN in gastric-cancer-associated angiogenesis by diminishing OPN expression in gastric cancer cells using the small interference RNA method, and then evaluate the effects of OPN on gastric cancer-associated angiogenesis by in vivo and in vitro assays. Our results revealed that reduced OPN production by gastric cancer cells would reduce the proliferation, migration, and tube formation of human umbilical vein endothelial cells, and lead to a lower microvessel density, i.e., angiogenesis, in transplanted tumors of mice. These data confirm the positive role of OPN in gastric-cancer-associated angiogenesis.
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PMID:Inhibition of osteopontin would suppress angiogenesis in gastric cancer. 1746 50

Angiotensin II (Ang II) has been reported to promote tumor progression, tumor growth and angiogenesis in many cancers. We previously observed that angiotensin II type 1 receptors (AT1R) were upregulated in human gastric cancer and may be involved in the progression of gastric cancer. We studied the effects of AT1R antagonist on angiogenesis and growth in gastric cancer xenografts to observe the mechanism action of AT1R in the gastric cancer. The results showed that the growth of gastric cancer cells was significantly suppressed by treatment with AT1R antagonist. In vivo, TCV-116, at doses of both 2 and 5 mg/kg/day, significantly suppressed tumor growth in mice (47.3 and 70.2%). Microvessel density was significantly decreased by TCV-116 (3.4 +/- 0.9 and 2.8 +/- 0.5 per field) compared with the control group (12.9 +/- 1.1 per field), and VEGF expression was significantly suppressed by AT1R antagonist. These results demonstrate that AT1R plays an important role in the progression of gastric cancer. Suppression tumor angiogenesis could be one of the mechanisms by which AT1R antagonist suppresses the growth of gastric cancer. These findings also provide a theoretical basis for the future clinical application of AT1R antagonist against gastric cancer.
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PMID:Angiotensin II type 1 receptor antagonist suppress angiogenesis and growth of gastric cancer xenografts. 1793 50

Discovery of tumor vascular specific molecules to improve the targeting ability of cytotoxic agents plays an important role in antiangiogenesis. We had found a peptide GX1 (CGNSNPKSC) binding to vasculature endothelial cells of human gastric cancer by phage display technology and its specificity to vasculature had been thoroughly confirmed in vitro. To further evaluate the applicability of GX1 in antiangiogenesis therapy of gastric cancer, immunohistochemical analysis and ECT imaging in nude mice were performed. Immunohistochemical analysis showed that GX1 phage produced positive staining on 51/65 (78%) cases of the vasculature of gastric cancer. Simultaneously GX1 peptide was labeled with (99)Tc(m)O(4)(-), which obtained with high labeling efficiency. (99)Tc(m)-GX1 could specifically bind to Co-HUVEC and HUVEC with a binding constant of 3062 pM and 3831 pM respectively. ECT imaging indicated that GX1 could efficiently target to xenographic tissue in mice model with a high tumor/heart radio than that of control peptide. Biodistribution showed that tumor uptake was 0.74+/-0.02% ID/g at 24 h, 11 times than that of muscle. Immunofluorescence showed GX1 peptide could bind to xenograft vasculature in vivo. The results confirmed the targeting specificity of GX1 in gastric cancer-associated angiogenesis. It would be promising to further develop GX1 peptide-based assay for tumor angiogenesis imaging to improve diagnosis and internal radiotherapy.
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PMID:Specific targeting of the vasculature of gastric cancer by a new tumor-homing peptide CGNSNPKSC. 1870 Jan 58

Gastrointestinal tract cancers constitute a group of highest morbidity both in and outside Japan, and the prognosis still remains unfavorable when the disease has progressed to the unresectable stage. Since the late 1990s, a novel category of anti-cancer drugs, 'molecular-targeted drugs', has become available, and angiogenesis has been considered as one of the most important molecular targets for antitumor therapy since it is essential for tumor growth. Anti-angiogenic therapy inhibits tumor angiogenesis and promotes apoptosis of existing tumor blood vessels, thereby intercepting the supply of oxygen and nutrition essential for tumor growth and metastasis. It was also suggested that anti-angiogenic therapy effectively normalizes abnormal vascular permeability, and thereby decreases the interstitial pressure, which may improve delivery of concomitantly used chemotherapeutic agents to tumor cells. Vascular endothelial growth factor (VEGF) acts as one of the most potent stimulating agents of angiogenesis, and several strategies targeting the VEGF signaling pathway have been developed, including anti-VEGF antibodies, soluble receptors binding directly to VEGF ligand, anti-VEGF receptor (VEGFR) antibodies and VEGFR tyrosine kinase inhibitors. The breakthrough in the clinical development of anti-angiogenic therapy against colorectal cancer came in 2003 with a large prospective, randomized clinical trial of bevacizumab, a monoclonal antibody directed against VEGF. Anti-angiogenic therapy has introduced a highly effective, completely new mode of action in this area and is the new standard of care in advanced colorectal cancer, while still being tested in gastric cancer due to its convincing clinical benefit and its tolerability and combinability with multiple chemotherapeutic agents.
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PMID:Anti-angiogenic therapy against gastrointestinal tract cancers. 1953 44

c-Ski, originally identified as a proto-oncogene product, is an important negative regulator of transforming growth factor (TGF)-beta family signaling through interaction with Smad2, Smad3, and Smad4. High expression of c-Ski has been found in some cancers, including gastric cancer. We previously showed that disruption of TGF-beta signaling by dominant-negative TGF-beta type II receptor in a diffuse-type gastric carcinoma model accelerated tumor growth through induction of tumor angiogenesis by decreased expression of the anti-angiogenic factor thrombospondin (TSP)-1. Here, we examined the function of c-Ski in human diffuse-type gastric carcinoma OCUM-2MLN cells. Overexpression of c-Ski inhibited TGF-beta signaling in OCUM-2MLN cells. Interestingly, c-Ski overexpression resulted in extensive acceleration of the growth of subcutaneous xenografts in BALB/c nu/nu female mice (6 weeks of age). Similar to tumors expressing dominant-negative TGF-beta type II receptor, histochemical studies revealed less fibrosis and increased angiogenesis in xenografted tumors expressing c-Ski compared to control tumors. Induction of TSP-1 mRNA by TGF-beta was attenuated by c-Ski in vitro, and expression of TSP-1 mRNA was decreased in tumors expressing c-Ski in vivo. These findings suggest that c-Ski overexpression promotes the growth of diffuse-type gastric carcinoma through induction of angiogenesis.
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PMID:c-Ski overexpression promotes tumor growth and angiogenesis through inhibition of transforming growth factor-beta signaling in diffuse-type gastric carcinoma. 1959 46

Gastric cancer is a deadly disease for which current therapeutic options are extremely limited. Vascular endothelial growth factor receptors and platelet-derived growth factor receptors regulate gastric cancer cell proliferation, invasion, and tumor angiogenesis. In the present study, we report that sorafenib therapy effectively inhibited tumor growth and angiogenesis in tumor xenografts. These were associated with reduction in the phosphorylation of vascular endothelial growth factor receptor-2 Tyr951, c-Kit Tyr568/570, platelet-derived growth factor receptor-beta Tyr1021, and Akt Ser473 and Thr308, down-regulation of positive cell cycle regulators, increased apoptosis, and up-regulation of p27. Sorafenib treatment also caused up-regulation of p-c-Raf Ser338 and p-extracellular signal-regulated kinase (ERK) Thr202/Tyr204 in gastric cancer xenografts. The combination of sorafenib and MAP/ERK kinase inhibitor AZD6244 enhances the effectiveness of each compound alone. Potential effect of sorafenib/AZD6244 included increase in proapoptotic Bim. Our data show that MAP/ERK kinase inhibition enhances the antitumor activity of sorafenib in vivo, supporting a rationale for multitargeted suppression of the angiogenesis and ERK signaling network in gastric cancer therapy.
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PMID:AZD6244 (ARRY-142886) enhances the therapeutic efficacy of sorafenib in mouse models of gastric cancer. 1972 82

Previous studies have demonstrated that interleukin-24 [IL-24; originally called melanoma differentiation associated gene-7 (mda-7)] as a novel tumor suppressor gene has tumor-suppressive activity against a broad spectrum of human cancers. However, the therapeutic effect of the recombinant human IL-24 (rhIL-24) protein purified from prokaryotic cells on gastric cancer has not been reported. In this study, we purified soluble rhIL-24 using Q-Sepharose column after the denaturing and renaturing process from the protein of Escherichia coli BL21 transfected with pET-21a(+)-hIL-24 vector and treated by isopropyl-beta-D-1-thiogalactopyranoside (IPTG) for enhanced expression of transgene rhIL-24. We demonstrated that rhIL-24 was capable of inducing in vitro apoptosis of SGC7901 gastric cancer cells and activating peripheral blood mononuclear cellsto secrete cytokines such as IL-6, TNF-alpha, and IFN-gamma. We also showed that rhIL-24 was able to inhibit formation of blood capillaries on chicken embryonic allantois and in vivo tumor angiogenesis leading to suppressing SGC7901 gastric cancer cell growth in vitro and in vivo possibly due to its downregulation of Bcl-2/Bax ratio, VEGF (vascular endothelial growth factor), and CD34. Therefore, our results indicate that rhIL-24 has potent suppressive effect on human SGC7901 gastric carcinoma cell line and warrant its further investigation for therapeutic application against gastric cancer.
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PMID:Recombinant human interleukin-24 suppresses gastric carcinoma cell growth in vitro and in vivo. 1991 46

Recent studies in molecular and cellular biology have shown that tumor growth and metastasis are not determined by cancer cells alone but also by a variety of stromal cells. The stroma constitutes a large part of most solid tumors, and cancer-stromal cell interaction contributes functionally to tumor growth and metastasis. Angiogenesis is the result of an imbalance between positive and negative angiogenic factors released by tumor and host cells into the microenvironment of the neoplastic tissue. In gastric cancer, tumor cells and stromal cells produce various angiogenic factors, including vascular endothelial growth factor, interleukin-8, and platelet-derived endothelial cell growth factor. The microenvironment in the gastric mucosa may also influence the angiogenic phenotype of gastric cancer. Helicobacter pylori infection increases expression of several angiogenic factors by tumor cells. Activated fibroblasts and macrophages in tumor stroma also play an important role in angiogenesis and tumor progression. We review the current understanding of cancer-stromal cell interaction as it pertains to tumor angiogenesis in gastric cancer.
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PMID:Cancer-stromal cell interaction and tumor angiogenesis in gastric cancer. 2002 Feb 78


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