Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A variety of human cancer cells are resistant to Fas ligand and anti-Fas antibody induced apoptosis. Previously, we reported that human gastric carcinoma cell lines were resistant to the anti-Fas antibody, CH-11, without interferon-gamma pretreatment in vitro. Cyclooxygenase (COX)-2 is known to be expressed in many human malignancies, and is correlated with tumor progression and resistance to apoptosis. This study examined whether NS398, a COX-2 inhibitor, inhibited cell proliferation and increased Fas-mediated apoptosis in human gastric carcinoma cell lines. Treatment of NS398 inhibited cell proliferation in MKN-45, which expressed the highest level of COX-2 among seven human gastric carcinoma cell lines, in a dose- and time-dependent manner, in contrast to less prominent effects in KATO-III, which expresses no COX-2. Although the treatment of CH-11 induced apoptosis in both cells, the simultaneous treatment of NS398 and CH-11 remarkably induced apoptosis, as confirmed by Hoechst 33258 staining and the terminal deoxynucleotidyl transferase- mediated dUTP-digoxigenin nick-end labeling (TUNEL) method in MKN-45. Flow cytometric analysis also revealed the increased pre-G1 fraction by the simultaneous treatment. The treatment of NS398 induced upregulation of Bad and PTEN, and downregulation of phosphorylated Akt (Thr308). These findings suggest that COX-2 might inhibit Fas-mediated apoptosis in human gastric carcinoma cell lines, especially MKN-45, by modulating PTEN and Akt.
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PMID:COX-2 inhibitor, NS398, enhances Fas-mediated apoptosis via modulation of the PTEN-Akt pathway in human gastric carcinoma cell lines. 1576 80

Epidemiological studies suggest that the frequent intake of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with a decreased risk of developing esophageal squamous cell carcinoma (SCC). This decrease is thought to correlate with the inhibition of cyclooxygenase (COX) activity. The production of prostaglandin E2 (PGE2), a major metabolite of COX, is increased in numerous human cancers including esophageal SCC, therefore, inhibition of COX activity and subsequent suppression of the formation of PGE2 may be chemopreventive in the esophagus. The objective of the present study was to determine whether L-748706 (L-706), a novel selective COX-2 inhibitor, would prevent N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor progression in the Fischer 344 (F344) rat. In rats pretreated with a low-dose of NMBA (0.25 mg/kg body weight), L-706 at 100 p.p.m. in the diet significantly reduced tumor multiplicity but not tumor incidence. At 150 p.p.m. in the diet, L-706 alone and in combination with 200 p.p.m. piroxicam produced significant reductions in both tumor incidence and multiplicity. Inhibition of tumor development in low-dose NMBA-treated rats was associated with reductions in esophageal cell proliferation rates and PGE2 levels in preneoplastic tissues. In contrast, in rats treated with a higher dose of NMBA (0.5 mg/kg body weight), neither L-706 alone nor in combination with piroxicam reduced esophageal tumor incidence or multiplicity in spite of the fact that they reduced esophageal PGE2 levels in preneoplastic tissues and in papillomas. Cell proliferation rates were reduced only in animals treated with L-706 + piroxicam. Our data suggest that the chemopreventive treatments were effective in inhibiting tumor development in NMBA-treated animals only when they reduced PGE2 levels in preneoplastic esophageal tissues approximately to those levels found in normal esophagus.
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PMID:The effects of L-748706, a selective cyclooxygenase-2 inhibitor, on N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis. 1587 14

Inflammatory angiogenesis is a critical process in tumor progression and other diseases. The inflammatory cytokine IL-1beta promotes angiogenesis, tumor growth, and metastasis, but its mechanisms remain unclear. We examined the association between IL-1beta-induced angiogenesis and cell inflammation. IL-1beta induced neovascularization in the mouse cornea at rates comparable to those of VEGF. Neutrophil infiltration occurred on day 2. Macrophage infiltration occurred on days 4 and 6. The anti-Gr-1 Ab-induced depletion of infiltrating neutrophils did not affect IL-1beta- or VEGF-induced angiogenesis. The former was reduced in monocyte chemoattractant protein-1-deficient (MCP-1(-/-)) mice compared with wild-type mice. After day 4, clodronate liposomes, which kill macrophages, reduced IL-1beta-induced angiogenesis and partially inhibited VEGF-induced angiogenesis. Infiltrating macrophages near the IL-1beta-induced neovasculature were COX-2 positive. Lewis lung carcinoma cells expressing IL-1beta (LLC/IL-1beta) developed neovasculature with macrophage infiltration and enhanced tumor growth in wild-type but not MCP-1(-/-) mice. A COX-2 inhibitor reduced tumor growth, angiogenesis, and macrophage infiltration in LLC/IL-1beta. Thus, macrophage involvement might be a prerequisite for IL-1beta-induced neovascularization and tumor progression.
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PMID:Infiltration of COX-2-expressing macrophages is a prerequisite for IL-1 beta-induced neovascularization and tumor growth. 1623 69

Proinflammatory mediators such as prostaglandins (PGs), nitric oxide (NO), certain inflammatory cytokines and chemokines play a pivotal role in tumor development. The anti-inflammatory properties of naturally occurring phytochemicals are associated with significant reduction in the risk of certain cancers in vitro and in vivo. In the present study, we investigated the effects of soybean saponins on the production of proinflammatory mediators in LPS-stimulated peritoneal macrophages. Soybean saponins significantly inhibited the release of PGE(2), NO, TNFalpha and monocyte chemotactic protein-1 (MCP-1) in a dose-dependent manner. Soybean saponins also down-regulated the expression of COX-2 and iNOS at mRNA/protein levels. Moreover, soybean saponins suppressed NF-kappaB activation by blocking IkappaB-alpha degradation. Our data indicate that soybean saponins exhibit anti-inflammatory properties by suppressing the transcription of inflammatory cytokine genes through the NF-kappaB signaling pathway. The anti-inflammatory properties of soybean saponins may be useful for ameliorating inflammatory diseases as well as suppressing tumor progression.
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PMID:Soybean saponins suppress the release of proinflammatory mediators by LPS-stimulated peritoneal macrophages. 1629 8

Gallbladder cancer is an asymptomatic disease in the early stage and no therapeutic measure is available except surgical intervention. The prognosis for patients with advanced,i.e., unresectable or metastatic disease is dismal, with median survival usually being less than 6 months if not treated with chemotherapy. To date, chemotherapy for gallbladder cancer has been limited by the absence of agents with effective cytotoxic activity. Thalidomide has been shown to have antiangiogenic and immunomodulatory effects, including the inhibition of vascular endothelial growth factor, basic fibroblast growth factor and tumor necrosis factor alpha. Celecoxib is a potent selective COX-2 inhibitor. The reported biological consequences of COX-2 up-regulation include inhibition of apoptosis, increased metastatic potential and promotion of angiogenesis. These events may contribute to cell transformation and tumor progression. Antiangiogenesis represents a significant new strategy for cancer treatment. Therefore,it is important to accept a wide range of different inhibitors such as thalidomide and selective COX-2 inhibitors with conventional cytotoxic agents. Here we show a case of unresectable gallbladder cancer with remarkable improvement in CA19-9 and prolongation of life.
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PMID:[A case report of unresectable gallbladder cancer that responded remarkably to the combination of thalidomide, celecoxib, and gemcitabine]. 1648 69

The prostaglandin E2 receptor, EP4 receptor (EP4R), plays an important role in the development of transitional cell carcinoma of the upper urinary tract (TCC-UUT). However, the clinical significance of other EP receptors (EP1R-3R) is not clear. Furthermore, the pathological function of EP receptors in such patients is not understood. In the present study, we examined the expression of EP1R-3R in 101 TCC-UUT tissues by immunohistochemistry. Furthermore, we defined the relationship between cyclooxygenase (COX)-2 and EP receptor expression, proliferation index (PI), microvessel density (MVD), and expression of metalloproteinase-2 (MMP-2), urokinase-type plasminogen activator (uPA), and exon v6 containing CD44 isoform (CD44 v6) by multivariate analysis. The expression of EP1R, EP2R, and EP3R was positive in 20 (19.8%), 26 (25.7%), and 14 (13.9%) tumor samples, respectively. Expression of these receptors was not associated with pathological findings or survival. COX-2 and EP4R were independently associated with MVD and MMP-2, and uPA or PI and MMP-2, respectively. Other EP receptors were not influenced by any factors. Our results suggest that EP1R-3R play a minimal role in cancer progression in patients with TCC-UUT. On the other hand, EP4R regulates tumor progression via cancer cell proliferation and MMP-2, distinct from COX-2.
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PMID:Pathological function of prostaglandin E2 receptors in transitional cell carcinoma of the upper urinary tract. 1660 7

Prostaglandins (PG) are members of a large group of hormonally active fatty acids derived from free fatty acids. They are formed from arachidonic acid-the major PG precursor. Cyclooxygenase (COX)-1 and -2 are the rate-limiting steps in PG synthesis. COX-2 is overexpressed in many human non-endocrine and endocrine tumors including colon, breast, prostate, brain, thyroid, and pituitary. COX-2 has an important role in angiogenesis and tumor growth. Thromboxane synthase (TS) catalyzes the synthesis of thromboxane A2 (TXA2), which is derived from arachidonic acid and prostaglandin H2 and is a vasoconstrictor and inducer of platelet aggregation. TXA2 stimulates tumor growth and spread of some tumors and TS appears to have a critical role in tumorigenesis in some organ systems. In this review, we examine the role of COX-2 and TS in various non-endocrine tumors, especially colon, breast, prostate, and brain as well as in endocrine tumors. The accumulating evidence points to an increasingly important role of COX-2 and TS in tumor progression and metastasis.
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PMID:Cyclooxygenase-2 and thromboxane synthase in non-endocrine and endocrine tumors: a review. 1662 14

Progression of human malignancies is accompanied by vascular events, such as formation and remodeling of blood vessels and systemic coagulopathy. Though long appreciated as comorbidity of cancer (Trousseau syndrome), vascular involvement is increasingly recognized as a central pathogenetic mechanism of tumor growth, invasion and metastasis. The major outstanding question in relation to this role has been, whether vascular perturbations are simply a reaction to the conditions of the tumor microenvironment, or are linked to the known genetic lesions causal for the onset and progression of malignancy. In this regard, we have previously hypothesized, and recently demonstrated experimentally that deregulation of certain hemostatic mechanisms, namely upregulation of tissue factor (TF) and possibly other changes (e.g. expression of thrombin receptor - PAR-1) are controlled by cancer-associated oncogenic events, such as activation of K-ras, epidermal growth factor receptor (EGFR), or inactivation of the p53 tumor suppressor gene in various human cancer cells. It appears that these respective transforming alterations exert their impact on both, cell-associated and soluble/circulating (microvesicle- associated) TF, i.e. may cause a systemic hypercoagulable state. Other genes, which more recently emerged as regulators of cancer coagulopathy include: PML-RARalpha, PTEN, and MET. While the spectrum of procoagulant targets of these genes may vary somewhat it includes: TF, PAI-1, COX-2 and possibly other hemostatic proteins. It is noteworthy that these prothrombotic changes may impact the malignant process directly (e.g. stimulate angiogenesis, tumor growth or metastasis) as a consequence of both coagulation-dependent and -independent effects. The latter are mostly related to cellular signaling events and changes in gene expression which are now known to be induced by the TF/FVIIa/Xa complex, thrombin and PARs, expressed on the surface of cancer cells, as well as tumor-associated endothelium. Interestingly, certain anticoagulants possess antimetastatic and anticancer properties (e.g. LMWH), an observation that further suggests that hypercoagulability may act as an effector mechanism of genetically driven tumor progression. Conversely, we suggest that oncogene-directed (targeted) anticancer agents could, at least in some cases, ameliorate not only cellular transformation itself, but also some of the chronic components of the cancer-related coagulopathy, something that may be relevant to therapeutic efficacy of these drugs. We also postulate that since TF is the oncogene target, circulating TF (microparticles) could serve as surrogate marker of the biological activity oncogene-directed agents exert in vivo. Thus, both genetic and epigenetic factors appear to conspire to activate various components of the hemostatic system in cancer patients, both locally and systemically. These activities act as mediators of cancer coagulopathy, angiogenesis, metastasis and other events involved in disease progression and should be recognized in designing better anticancer therapies.
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PMID:Genetic determinants of cancer coagulopathy, angiogenesis and disease progression. 1663 63

Prostaglandin E(2) (PGE(2)), a proinflammatory bioactive lipid, promotes cancer progression by modulating proliferation, apoptosis, and angiogenesis. PGE(2) is a downstream product of cyclooxygenase (COX) and is biochemically inactivated by prostaglandin dehydrogenase (PGDH). In the present study, we investigated the mechanisms by which PGDH is down-regulated in cancer. We show that epidermal growth factor (EGF) represses PGDH expression in colorectal cancer cells. EGF receptor (EGFR) signaling induces Snail, which binds conserved E-box elements in the PGDH promoter to repress transcription. Induction of PGE(2) catabolism through inhibition of EGFR signaling blocks cancer growth in vivo. In human colon cancers, elevated Snail expression correlates well with down-regulation of PGDH. These data indicate that PGDH may serve a tumor suppressor function in colorectal cancer and provide a possible COX-2-independent way to target PGE(2) to inhibit cancer progression.
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PMID:Repression of prostaglandin dehydrogenase by epidermal growth factor and snail increases prostaglandin E2 and promotes cancer progression. 1681 38

Oral cancer is a major health problem in many parts of the world including India. The molecular mechanisms involved in oral tumorigenesis are not completely understood. Although surgery continues to be the most common treatment modality for this cancer, survival rates of oral cancer patients have still not significantly improved over the last few decades. Classical diagnostic methods are still not sensitive enough in detecting completeness of surgery and assessing minimal residual disease. This study investigated the role of NF-kappaB and COX-2 both in oral cancer progression and assessment of minimal residual disease. Expression of NF-kappaB proteins and its inhibitory protein IkappaB-alpha was evaluated using immunohistochemistry, ELISA and EMSA, while RT-PCR was used to detect COX-2 expression. Cytoplasmic expression as well as nuclear translocation of NF-kappaB proteins increased with histological progression of oral cancer (from normal to leukoplakia to cancer). A similar pattern of expression was observed for COX-2 also. NF-kappaB proteins, both cytoplasmic and nuclear, had a significant negative correlation from tumor to surgical margin to extra margin; COX-2 paralleled the expression of NF-kappaB proteins. Our results thus point to NF-kappaB and COX-2 as participants in oral tumor progression and also to the validation of these two molecular markers in assessing minimal residual disease.
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PMID:NF-kappaB and COX-2 during oral tumorigenesis and in assessment of minimal residual disease in surgical margins. 1682


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