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)

A large number of epidemiological studies have shown that regular use of aspirinor other nonsteroidal anti-inflammatory drugs (NSAIDs) results in a 40-50% reduced risk of colorectal cancer (CRC). Furthermore, NSAIDs cause the regression of preexisting adenomas in patients with familial adenomatous polyposis and significantly inhibit tumor growth in animal models of CRC. To establish a CRC liver metastasis model, we implanted mouse colon tumor MC-26 cells into the splenic subcapsule of BALB/c mice, after which mice were given either standard chow or chow containing the cyclooxygenase (COX)-2-specific inhibitor rofecoxib, alone or in combination with the standard antineoplastic agents, 5-fluoruracil or irinotecan. After 14 days, mice that were given rofecoxib or irinotecan, but not 5-fluoruracil, had significantly smaller primary tumors and fewer metastases. Rofecoxib, at clinical anti-inflammatory plasma concentrations, enhanced the effects of both antineoplastic agents when used in combination. Biochemical analyses of the primary splenic tumor in rofecoxib-treated mice showed no alteration in COX-1 expression, but significant decreases in the expression of the tumor-promoting proteins COX-2, cyclin D1, cytosolic beta-catenin, matrix metalloproteinases-2 and -9, and vascular endothelial cell- derived growth factor. Rofecoxib also decreased growth-enhancing prostaglandin E(2) and tumor-suppressive interleukin-10, whereas antineoplastic interleukin-12 was increased. Two separate survival studies were performed. When mice were fed chow containing 0.01% rofecoxib beginning on day 0 after tumor cell implantation, which achieved clinical anti-inflammatory plasma concentrations, survival time was significantly longer compared with mice given control chow. After 30 days, mortality in the control group was 90%, whereas only one mouse (5%) treated with rofecoxib had died after 30 days. In the second survival study, all of the mice were initially fed with regular chow after tumor cell implantation. On day 7, mice were randomly divided into three dietary groups: control chow, low-dose (0.01%) rofecoxib chow, and high-dose (0.025%) rofecoxib chow. After 28 days, mortality was 100%, 20%, and 10% in control, low-, and high-dose rofecoxib fed groups, respectively. These studies demonstrate that rofecoxib decreases the growth and metastatic potential of CRC in mice through multiple mechanisms. These studies in mice also provide important information that supports the benefit of COX-2 inhibition, not only in the prevention of CRC, but also potentially in the treatment of this common malignancy. Clinical trials will be necessary to assess the utility of COX-2 inhibitors as adjuvant therapy for early-stage disease and as potential agents, either alone or in combination, with more established drugs, for the treatment of refractory CRC.
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PMID:Inhibition of cyclooxygenase-2 by rofecoxib attenuates the growth and metastatic potential of colorectal carcinoma in mice. 1256

Osteosarcoma by nature shows aggressive pulmonary metastasis; however, the underlying molecular mechanisms remain unclear. We previously showed that N-cadherin and cadherin-11 (OB-cadherin), which are highly expressed in normal osteoblasts, are anomalously expressed in human osteosarcoma (Kashima et al., Am J Pathol 1999;155:1549-55). In the present study, we examined the role of cadherins in osteosarcoma metastasis using the mouse osteosarcoma cell line Dunn and its highly metastatic subline LM8. Oligonucleotide array and RT-PCR analyses demonstrated that Dunn and LM8 cells did not express appreciable levels of several members of the cadherin family, and Western blot analysis confirmed that Dunn and LM8 cells did not express P-cadherin, E-cadherin, N-cadherin or cadherin-11 protein. We therefore investigated the functional consequences of cadherin overexpression on cell migration and in vivo metastatic potential of LM8 cells. Several LM8 clones were isolated which expressed exogenous N-cadherin and cadherin-11 localized to the cell membrane and able to bind to beta-catenin. Overexpression of N-cadherin or cadherin-11 in LM8 cells did not affect cell proliferation but caused an inhibitory effect on cell migration in vitro. In vivo analysis showed that N-cadherin- and cadherin-11-overexpressing cells exhibited a marked reduction in their ability to form pulmonary metastases, with significant decreases in lung weight and the number and weight of metastatic lesions, as well as the size and weight of primary lesions at the s.c.-inoculated site. These observations demonstrate that disruption of N-cadherin- and cadherin-11-mediated cell-cell adhesion is critical in the pulmonary metastasis of osteosarcoma.
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PMID:Overexpression of cadherins suppresses pulmonary metastasis of osteosarcoma in vivo. 1256 68

Studies on the expression of beta-catenin (beta-ct) in gastric carcinoma have provided conflicting results, and the role played by beta-ct mutations in gastric carcinogenesis remains unclear. In an attempt to clarify the aforementioned issues we undertook the retrospective study of 157 gastric carcinomas by using immunohistochemistry and molecular genetics. Reduced/absent membranous beta-ct expression was significantly associated with isolated-cell/diffuse histotype both in "pure" diffuse gastric carcinomas and in the isolated-cell/diffuse component of mixed carcinomas. Cytoplasmic and/or nuclear beta-ct expression was particularly prevalent in mixed carcinomas and was significantly associated with lymphatic vessel invasion and lymph node metastases. beta-ct mutations were not detected in any case. We conclude that the pattern of beta-ct expression is closely related to gastric carcinoma histotype. The activation of Wnt/beta-ct pathway is associated with mixed gastric carcinoma and with features of clinical aggressiveness; the mechanism(s) underlying this pathway in gastric carcinoma are not due to beta-ct mutations and remain to be elucidated.
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PMID:Patterns of beta-catenin expression in gastric carcinoma: clinicopathological relevance and mutation analysis. 1259 10

To investigate the genetic mechanism of metastatic spread in hepatocellular carcinoma (HCC), we analyzed genomic changes in lung or liver metastases and the corresponding primary tumors (83 tumor samples) in 18 patients who underwent orthotopic liver transplantation. We studied the incidence of microsatellite instability (MSI) and loss of heterozygosity (LOH) involving 8 highly polymorphic microsatellite markers and the polyA tract, Bat26. We also sought alterations of p53 and beta-catenin gene mutations. High MSI (>30-40% of the loci analyzed) was found only in primary tumors (11%), whereas LOH was observed in 50% of primary and in 39% of recurrent tumors. p53 mutations were found in 2 cases of primary HCC but not in the corresponding metastases. P53 was overexpressed in 4 primary HCC (22%) and 7 metastases (39%). The percentage of beta-catenin gene mutations was low (6%). Lung metastases retained the D16S402 microsatellite abnormalities observed in the primary tumors, whereas recurrent liver tumor did not (p = 0.02). In conclusion, LOH and P53 protein overexpression, rather than mutations in the p53 or beta-catenin genes or MSI, seem to be involved in the spreading of HCC, suggesting the presence of metastasis suppressor genes in the vicinity of the chromosomal loci in question.
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PMID:Analysis of chromosomal instability in pulmonary or liver metastases and matched primary hepatocellular carcinoma after orthotopic liver transplantation. 1264 Jun 82

To evaluate whether beta-catenin signaling has a role in the regulation of angiogenesis in colon cancer, a series of angiogenesis-related gene promoters was analyzed for beta-catenin/TCF binding sites. Strikingly, the gene promoter of human vascular endothelial growth factor (VEGF, or VEGF-A) contains seven consensus binding sites for beta-catenin/TCF. Analysis of laser capture microdissected human colon cancer tissue indicated a direct correlation between up-regulation of VEGF-A expression and adenomatous polyposis coli (APC) mutational status (activation of beta-catenin signaling) in primary tumors. In metastases, this correlation was not observed. Analysis by immunohistochemistry of intestinal polyps in mice heterozygous for the multiple intestinal neoplasia gene (Min/+) at 5 months revealed an increase and redistribution of VEGF-A in proximity to those cells expressing nuclear beta-catenin with a corresponding increase in vessel density. Transfection of normal colon epithelial cells with activated beta-catenin up-regulated levels of VEGF-A mRNA and protein by 250-300%. When colon cancer cells with elevated beta-catenin levels were treated with beta-catenin antisense oligodeoxynucleotides, VEGF-A expression was reduced by more than 50%. Taken together, our observations indicate a close link between beta-catenin signaling and the regulation of VEGF-A expression in colon cancer.
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PMID:beta-Catenin regulates vascular endothelial growth factor expression in colon cancer. 1281 Jun 42

Increased expression and/or activity of c-Met, the receptor protein tyrosine kinase for hepatocyte growth factor/scatter factor, occurs commonly during colon tumor progression. To examine potential roles for c-Met in promoting metastasis, we compared the colon tumor cell line KM12C with low metastatic potential to the isogenic variants KM,12L4 and KM12SM with high metastatic potential. KM12C cells express c-Met with low levels of tyrosine phosphorylation in the absence of HGF. The high metastatic cells express a c-Met that is constitutively tyrosine phosphorylated, they have increased colony formation, and are minimally responsive to HGF relative to the parental cells. Tyrosine-phosphorylated beta-catenin was constitutively associated with c-Met in the more metastatic cells, but was inducible only after HGF addition in the less metastatic cells. Functions mediated by beta-catenin, including cell-cell adhesion and migration, and activation of the tcf (T-cell factor) family of transcription factors, were also elevated in the more metastatic KM12SM and L4 cells. Furthermore, analysis of the known tcf transcriptional target genes, cyclin D1, c-Myc, and uPAR, demonstrated increased expression in the high metastatic cells, correlating with the levels of tcf activity. Collectively, these results suggest that endogenous activation of c-Met in highly metastatic KM12SM CRC cells results in increased survival and growth under anchorage independent conditions, increased in vitro migration, and elevated levels of tcf target genes. Thus, beta-catenin association with activated c-Met may contribute to a more aggressive liver metastatic phenotype of these cells.
Clin Exp Metastasis 2003
PMID:Activation of c-Met in colorectal carcinoma cells leads to constitutive association of tyrosine-phosphorylated beta-catenin. 1285 16

Chronic inflammation has been reported to accelerate neoplasmas in gastrointestinal tract. Certain bacteria including Helicobacter pylori directly interact with host cells, induce proinflammatory cytokines and stimulate production of free radicals. Free radicals cause mutations in target cells so that neoplastic clones are established. Accumulation of such genetic alterations may cause malignant transformation of some established clones. In addition, inflammatory alterations may promote growth, expansion and invasion of gastrointestinal epithelial cells. The latter changes caused by inflammation may occur even without further genetic mutations or epigenetic alterations, and therefore may be categorized as 'perigenetic alterations' of neoplastic cells. For an example, tumour necrosis factor alpha (TNF-alpha) plays pivotal roles not only in the reduction but also in the growth, invasion and metastases of certain neoplasmas. Our studies show that TNF-alpha increases intracellular radical production, degradates E-cadherin / beta-catenin complex and promotes dispersion and migration in epithelial cells transformed with an activated src oncogene (v-src). These data indicate that an inflammatory cytokine induces the malignant potential of src-activated neoplastic cells. Interestingly, TNF-alpha also induced these phenotypic changes in nonmutated cells whose c-Src was activated by TGF-alpha, suggesting that the invasive properties of the cell were not necessarily related to gene mutation. Furthermore, certain radical scavengers suppressed the invasive phenotype of the cells. These results indicate that perigenetic alterations are an important target of pharmacological intervention of carcinogenesis.
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PMID:Review article: inflammation-related promotion of gastrointestinal carcinogenesis--a perigenetic pathway. 1292 44

Wilms' tumour is a pediatric neoplasm exhibiting histologic features of developing kidney. Although the majority of Wilms' tumour patients are treated effectively, approximately 15% develop metastases and of these, 30% succumb to their disease. The biologic factors governing Wilms' tumour metastasis are largely unknown. Attempts at deriving representative Wilms' tumour cell lines, which could facilitate functional studies, have only been partially successful thus far. We now report on derivation and characterization of a Wilms' tumour cell line, WiT 49, from a first-generation xenograft of a human Wilms' tumour lung metastasis. WiT 49 recapitulates the phenotype of the parent tumours (primary and lung metastasis) and expresses normal WT1, overexpresses IGFII and carries a frequently identified p53 mutation. We recently reported overexpression of hepatocyte growth factor(HGF) and its receptor met in a series of Wilms' tumours with higher levels in homotypic metastatic cases. We therefore examined WiT 49 for expression of HGF/met and for met signaling targets associated with cell adhesion and cytoplasmic mediators of transcription using Western blot, co-immunoprecipitation, immunofluorescence labeling and zymography. Our results show co-expression of HGF and met protein, absence of E-cadherin, high levels of beta-catenin co-immunolocalized to met at the cell membrane and moderate levels of gamma-catenin and ezrin protein expression. After cell fractionation, beta-catenin was detected in the cytoplasm and nuclei of WiT 49 with relatively higher levels in the cytoplasm as compared to nuclei. Examination of MMP expression in WiT 49 showed constitutive activation of MMP 9 and latent MMP 2 supporting possible beta-catenin-mediated transcriptional activation. The WiT 49 cell line responded to recombinant human HGF by an increase in the expression of the met receptor, recruitment of the Gab-1 adapter protein to met and release of bound beta-catenin from met. Our studies therefore establish WiT 49 as a representative Wilms' tumour cell line derived from a lung metastasis that co-expresses HGF/met and shows absence of the cadherin-catenin complex supporting a role for these factors in regulation of the invasive and metastatic phenotype in Wilms' tumour.
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PMID:Derivation and characterization of a Wilms' tumour cell line, WiT 49. 1450 35

The protein beta-catenin can not be degraded in CRC due to different reasons. This leads to an increased formation of beta-catenin/Tcf4 complex, which has a strong transcription factor activity. We investigated the mRNA expression of beta-catenin and Tcf4 in N, T and M in 12 cell lines and in tissues samples of 14 patients. We found a significant increase of beta-catenin mRNA expression in the primary tumors and in the metastases. These data show for the first time that apart from the known mechanisms the overexpression of beta-catenin mRNA can be an additional factor contributing to the increase of beta-catenin amount in cells of CRC. The resulting increased transcription of hitherto unknown target genes might be involved in the progression and the metastatic process of CRC.
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PMID:[beta-catenin overexpression in metastasized colorectal carcinoma--an important mechanism in progression of the disease?]. 1451 65

Small cell carcinoma of the endometrium (SCCE) is extremely rare. Previous reports indicate that SCCE frequently shows systemic spread and has a poor prognosis. Beta-catenin has been shown to be a key downstream effector of the Wnt signaling pathway, which regulates cell growth and survival. Decreased membranous expression of beta-catenin in cancers correlates with poor prognosis and is associated with dissemination of tumor cells and the formation of metastases. Recently, some different investigators demonstrated aberrant beta-catenin accumulation in neuroendocrine tumors arising in different organs, suggesting a role for the Wnt/beta-catenin signaling pathway during neuroendocrine tumorigenesis. Here, we report a new case of SCCE associated with peritoneal spreading and aggressive course; the patient died one month after surgery. This study also aimed at assessing the involvement of the Wnt signaling pathway in this rare neuroendocrine tumor. Interestingly, both intense nuclear beta-catenin accumulation and cyclin D1 immunoreactivity were restricted to carcinoma cells invading lymphatic vessels. However, mutation analysis failed to demonstrate any mutation in exon 3 of the beta-catenin gene or exon 15 of the APC gene in the present case. Although the mechanism of nuclear accumulation of beta-catenin is still unknown, the heterotopic nuclear localization of beta-catenin may play a role in the tumor invasion process and, subsequently, may be associated with the aggressive behavior of SCCE.
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PMID:Small cell carcinoma of the endometrium: report of a case with analysis of Wnt/beta-catenin pathway. 1453 40


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