Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hypoxia-inducible transcription factor 1 (HIF-1) and HIF-2alpha regulate the expression of an expansive array of genes associated with cellular responses to hypoxia. Although HIF-regulated genes mediate crucial beneficial short-term biological adaptations, we hypothesized that chronic activation of the HIF pathway in cardiac muscle, as occurs in advanced ischemic heart disease, is detrimental. We generated mice with cardiac myocyte-specific deletion of the von Hippel-Lindau protein (VHL), an essential component of an E3 ubiquitin ligase responsible for suppressing HIF levels during normoxia. These mice were born at expected frequency and thrived until after 3 months postbirth, when they developed severe progressive heart failure and premature death. VHL-null hearts developed lipid accumulation, myofibril rarefaction, altered nuclear morphology, myocyte loss, and fibrosis, features seen for various forms of human heart failure. Further, nearly 50% of VHL(-/-) hearts developed malignant cardiac tumors with features of rhabdomyosarcoma and the capacity to metastasize. As compelling evidence for the mechanistic contribution of HIF-1alpha, the concomitant deletion of VHL and HIF-1alpha in the heart prevented this phenotype and restored normal longevity. These findings strongly suggest that chronic activation of the HIF pathway in ischemic hearts is maladaptive and contributes to cardiac degeneration and progression to heart failure.
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PMID:Hypoxia-inducible factor-dependent degeneration, failure, and malignant transformation of the heart in the absence of the von Hippel-Lindau protein. 1828 56

Metastatic cancer is a complex positive feedback loop system. Such as system has a tendency to acquire extreme robustness. Signaling pathways controlling that robustness can fail completely if an essential element from the signaling is removed. That element is a locus of fragility. Targeting that locus represents the best way to target the cancer robustness. This prospect presents another locus of fragility in signaling complex system network, controlling the cell cycle progression through the PI3K/AKT/mTOR/RAN pathway and cell migration and angiogenesis through the VEGF/PI3K/AKT/NO/ICAM-1 pathway. The locus of fragility of these pathways is AKT, which is regulated by a balance of catalase/H2O2 or by AKT inhibitor. Tiny and trivial perturbations such as change in redox state in the cells by antioxidant enzyme catalase, scavenging H2O2 signaling molecule, regulates robust signaling molecule AKT, abolishing its phosporilation and inducing cascading failure of robust signaling pathways for cell growth, proliferation, migration, and angiogenesis. An anticancer effect of the antioxidant is achieved through the AKT locus, by abolishing signals from growth factors VEGF, HGF, HIF-1alpha and H2O2. Previously reported locus of fragility nitric oxide (NO) and locus AKT are close in the complex signaling interactome network, but they regulate distinct signaling modules. Simultaneously targeted loci represents new principles in cancer robustness chemotherapy by blocking cell proliferation, migration, angiogenesis and inducing rather slow then fast apoptosis leading to slow eradication of cancer.
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PMID:AKT as locus of fragility in robust cancer system. 1842 70

Histone deacetylase inhibitory prodrugs that are metabolized to butyric acid and formaldehyde possess antineoplastic properties and low toxicity. We sought to characterize the antiangiogenic and antimetastatic activities of two lead prodrugs, pivaloyloxymethyl butyrate (AN-9) and butyroyloxymethyl-diethyl phosphate (AN-7) in murine cancer models. In the sc implanted human colon carcinoma HT-29 xenograft model AN-7, exhibited superior anticancer activity compared to AN-9, as was evident by the significantly greater inhibition of tumor growth and reduction of serum CEA. AN-7 was also more effective in reducing mean vessel density (MVD) by 7-fold, bFGF, Ki-67 (7-fold) and HIF-1alpha in immunohistochemically stained tumor sections. Semi-quantitative evaluation of the levels of bFGF, HDAC1 and HIF-1alpha by Western blot analysis showed a decrease in expression only in the tumors of mice treated with AN-7. The level of bFGF was reduced 3-fold in the tumor and that of TIMP1 was elevated (by 3-fold) in the serum of AN-7 treated mice. In a 4T1 metastatic breast carcinoma model, AN-7 inhibited the formation of lung lesions by 76% and AN-9 by 47%, further demonstrating the greater efficacy of AN-7 compared to AN-9 (P<0.02). Both AN-7 and AN-9 exhibited antimetastatic and antiangiogenic activities by reducing vascularization, bFGF expression and HIF-1alpha. Yet, AN-7 was more potent than AN-9.
Clin Exp Metastasis 2008
PMID:Histone deacetylase inhibitors: the anticancer, antimetastatic and antiangiogenic activities of AN-7 are superior to those of the clinically tested AN-9 (Pivanex). 1850 86

Neoplastic cells growing under hypoxic conditions exhibit a more aggressive phenotype by activating a cascade of molecular events partly mediated by hypoxia-inducible transcription factor (HIF-1alpha) and vascular endothelial growth factor (VEGF). The roles of these markers have been studied previously in several cancer lines. We ascertained the frequency of HIF-1alpha expression, VEGF expression, the degree of neovascularization, and cell proliferation in osteosarcoma samples. Samples from osteosarcoma patients were assessed for HIF-1alpha and VEGF protein expression using immunohistochemistry, neovascularization using antibodies for Factor VIII, and cell proliferation using the Ki-67 labeling index. Associations between these parameters and clinical features were examined. HIF-1alpha staining was positive in 35% of patients and metastases were present in 61% of these HIF-1alpha-positive patients. VEGF protein expression was detected in 69% of patients, 92% of whom were female. We observed an insignificant trend for a higher frequency of VEGF expression in the high-grade as compared to low-grade osteosarcoma. We observed no association between vascular density and proliferation index and any clinical parameters. We found an association between HIF-1alpha expression and metastatic disease and between VEGF expression and female gender.
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PMID:Hypoxia markers in human osteosarcoma: an exploratory study. 1852 39

The ubiquitin ligase Siah2 has been shown to regulate prolyl hydroxylase 3 (PHD3) stability with concomitant effect on HIF-1alpha availability. Because HIF-1alpha is implicated in tumorigenesis and metastasis, we used SW1 mouse melanoma cells, which develop primary tumors with a propensity to metastasize, in a syngeneic mouse model to assess a possible role for Siah2 in these processes. Inhibiting Siah2 activity by expressing a peptide designed to outcompete association of Siah2-interacting proteins reduced metastasis through HIF-1alpha without affecting tumorigenesis. Conversely, inhibiting Siah2 activity by means of a dominant-negative Siah2 RING mutant primarily reduced tumorigenesis through the action of Sprouty 2, a negative regulator of Ras signaling. Consistent with our findings, reduced expression of PHD3 and Sprouty2 was observed in more advanced stages of melanoma tumors. Using complementary approaches, our data establish the role of Siah2 in tumorigenesis and metastasis by HIF-dependent and -independent mechanisms.
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PMID:The ubiquitin ligase Siah2 regulates tumorigenesis and metastasis by HIF-dependent and -independent pathways. 1894 40

The transcription factor hypoxia-inducible factor 1 (HIF-1) alpha is abundantly expressed in the majority of human carcinomas and their metastases. HIF-1alpha controls central metastasis-associated pathways such as glycolysis, angiogenesis, and invasion. Functional inhibition of HIF-1alpha leads to impaired metastasis formation in murine tumor models. However, the precise molecular mechanisms underlying the metastasis-promoting role of HIF-1alpha have not been fully characterized. The ability of transformed epithelial cells to initiate the metastatic cascade relies on their ability to escape anoikis, a default program of apoptosis induction following loss of integrin anchoring to the extracellular matrix. Therefore, we addressed the function of HIF-1alpha in anoikis resistance and anchorage-independent growth. Inhibition of HIF-1alpha via RNA interference resulted in up-regulation of alpha5 integrin on the cell surface of human gastric cancer cells, whereas other integrins remained unaffected. Integrin alpha5 induction occurred at the level of transcription and was dependent on elevated intracellular superoxide in HIF-1alpha-knockdown cells. HIF-1alpha-deficient cells displayed significantly increased anoikis susceptibility due to up-regulated alpha5 integrin. Finally, colony formation in soft agar was shown to be dependent on HIF-1alpha as HIF-1alpha-deficient cells displayed a 70% reduction in anchorage-independent proliferation. Results obtained by RNA interference could be entirely confirmed by application of the pharmacologic HIF-1alpha-inhibitor 2-methoxyestradiol. Hence, our data argue for a pivotal role for HIF-1alpha in anoikis control via suppression of alpha5 integrin. HIF-1alpha-inhibiting drugs might therefore offer an innovative strategy for antimetastatic cancer therapy.
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PMID:Hypoxia-inducible factor 1alpha mediates anoikis resistance via suppression of alpha5 integrin. 1907 77

Gastric adenocarcinoma is characterised by rapid emergence of systemic metastases, resulting in poor prognosis due to vanished curative treatment options. Better understanding of the molecular basis of gastric cancer spread is needed to design innovative treatments. The transcription factor HIF-1alpha (hypoxia-inducible factor 1alpha) is frequently overexpressed in human gastric cancer, and inhibition of HIF-1alpha has proven antitumour efficacy in rodent models, whereas the relevance of HIF-1alpha for the metastatic phenotype of gastric adenocarcinoma remains elusive. Therefore, we have conducted a comprehensive analysis of the role of HIF-1alpha for pivotal metastasis-associated processes of human gastric cancer. Immunhistochemistry for HIF-1alpha showed specific staining at the invading tumour edge in 90% of human gastric cancer samples, whereas normal gastric tissue was negative and only a minority of early gastric cancers (T1 tumours) showed specific staining. Hypoxia-inducible factor 1alpha-deficient cells showed a significant reduction of migratory, invasive and adhesive properties in vitro. Furthermore, the HIF-1alpha-inhibitor 2-methoxy-estradiol significantly reduced metastatic properties of gastric cancer cells. The accentuated expression at the invading edge together with the in vitro requirement of HIF-1alpha for migration, invasion and adherence argues for a pivotal role of HIF-1alpha in local invasion and, ultimately, systemic tumour spread. These results warrant the exploration of HIF-1alpha-inhibiting substances in clinical treatment studies of advanced gastric cancer.
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PMID:HIF-1alpha determines the metastatic potential of gastric cancer cells. 1922 95

The chemokine and chemokine receptor families have important roles in tumorigenesis. Although CXCR4 and CCR7 have been reported to be associated with cancer metastasis, the role of other chemokine receptors in cancer is poorly understood. We explored the status of CXCR6 in hypoxia-induced cell migration. Breast cancer cells and human umbilical vein endothelial cells (HUVEC) expressed CXCR6, and showed appreciable chemotactic migration to CXCL16. Significant accumulation of CXCR6 mRNA and protein during hypoxia was observed. Overexpression of CXCR6 increased cell migration, and knockdown of CXCR6 attenuated hypoxia-mediated cell migration and MMP-2 secretion. To investigate possible mechanisms regulating CXCR6 expression during hypoxia, we detected the expression of HIFs and found that HIF-1alpha was involved in CXCR6 regulation. CXCR6 and HIF-1alpha were highly expressed in breast cancer lymph nodes metastases. Our data suggest CXCR6 contributes significantly to cell migration during hypoxia.
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PMID:Chemokine C-X-C motif receptor 6 contributes to cell migration during hypoxia. 1923 Oct 68

Chemokines and their receptors are involved in tumourigenicity and clinicopathological significance of chemokines receptor expression in pancreatic adenocarcinoma (PA) is not fully understood. This study was conducted to determine patients' outcome according to the expressions of CXCR4, CXCR7 and HIF-1alpha after resection of PA. Immunohistochemistry for CXCR4, CXCR7 and HIF-1alpha expressions as well as cell proliferative index (Ki-67) was conducted in 71 resected (R0) PA and their 48 related lymph nodes (LN) using tissue microarray. CXCR4 and CXCR7 expressions were positively correlated to HIF-1alpha suggesting a potential role of HIF-1alpha in CXCR4 and CXCR7 transcription activation. Patients with CXCR4(high) tumour expression had shorter OS than those with low expression (median survival: 9.7 vs 43.2 months, P=0.0006), a higher risk of LN metastases and liver recurrence. In multivariate analysis, high CXCR4 expression, LN metastases and poorly differentiated tumour are independent negative prognosis factors. In a combining analysis, patients with a CXCR7(high)/CXCR4(high) [corrected] tumour had a significantly shorter DFS and OS than patients with a CXCR4(low)/CXCR7(low) [corrected] tumour. CXCR4 in resected PA may represent a valuable prognostic factor as well as an attractive target for therapeutic purpose.
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PMID:High expression of CXCR4 may predict poor survival in resected pancreatic adenocarcinoma. 1935 87

Metastasis as a complex process involves loss of adhesion, migration, invasion and proliferation of cancer cells. Sulforaphane (SFN) is one of naturally occurring cancer chemopreventive isothiocyanates found in cruciferous vegetables, consumption of which has been associated with reduced risk of cancer. In this study, we describe effect of SFN on various aspects determining invasive behavior of MDA-MB-231 human breast carcinoma cells. We studied modulation of molecules associated with epithelial to mesenchymal transition (EMT), hypoxic marker CA IX and mitochondrially located peripheral benzodiazepine receptor (PBR) using flow cytometry, gene expression of matrix metalloproteinases MMP1, 3, 7, 9, 14, transcription factors POU5F1 and Twist1 mRNA by RT PCR, and cytokine production by multiplex bead assay. SFN downregulated PBR and vimentin expression in a dose dependent manner, but significantly affected neither HIF-1alpha, nor CA IX protein expression, nor VEGF and GLUT1 mRNA levels. Among studied MMPs, MMP7 and MMP14 mRNA were downregulated while no apparent effect on MMP1, MMP3 and MMP9 was observed. Further, we found significant down regulation of Twist1 and POU5F1, transcription factors that mediate EMT and the self-renewal of undifferentiated embryonic stem cells. SFN reduced also the production of pro-inflammatory cytokines IL-1beta, IL-6, TNF-alpha, IFN-gamma, immunomodulating cytokine IL-4 and growth factors involved in angiogenesis PDGF and VEGF. Our study shows that SFN efficacy is associated with the reversal of several biological characteristics connected with EMT or implicated in the matrix degradation and extracellular proteolysis, as well as with reduced production of pro-inflammatory cytokines and pro-angiogenic growth factors in MDA-MB-231 cells.
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PMID:Modulation of markers associated with aggressive phenotype in MDA-MB-231 breast carcinoma cells by sulforaphane. 1972 65


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