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)

Nasopharyngeal carcinoma is intimately associated with the Epstein-Barr virus (EBV), which we have exploited therapeutically by constructing an EBV-specific synthetic enhancer sequence, within an adenoviral vector, denoted as adv.oriP. The achievement of tumor targeting provides therapeutic potential when delivered systemically, which could impact on distant metastases. We demonstrate here the feasibility and potential utility of combined, minimally invasive in vivo bioluminescence and fluorescence imaging to monitor adenoviral infection of subcutaneous C666-1 nasopharyngeal xenograft tumors stably expressing the DsRed2 gene. Fluorescence imaging was used to monitor the location and size of the C6661.DsRed2 tumors, whereas bioluminescence imaging demonstrated the distribution and specificity of a transcriptionally targeted adenoviral vector, adv.oriP.fluc, expressing the firefly luciferase gene. Fluorescence, bioluminescence, and photographic images were aligned using grids to examine colocalization of adenovirus and tumors. Bioluminescence and fluorescence co-localized in 92% (11/12) of tumors at 24 hr and 100% (12/12) at 96 hr after adv.oriP.fluc (10(9) ifu) was administered intravenously. Nonspecific luciferase signal was detected in the liver area. The combined imaging was therefore successful in monitoring the uptake of systemically administered adenovirus in implanted tumors. This may ultimately lead to an effective noninvasive method to monitor the response of metastases to adenoviral gene therapy.
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PMID:Combined in vivo bioluminescence and fluorescence imaging for cancer gene therapy. 1580 52

We reported earlier that IL-1beta, an NF-kappaB-regulated cytokine, was made by intestinal epithelial cells during detachment-induced apoptosis (anoikis) and that IL-1 was antiapoptotic for detached cells. Since surviving anoikis is a prerequisite for cancer progression and metastases, we are further exploring the link between anoikis and cytokines. Here we determined that multiple genes are expressed following detachment including a number of NF-kappaB-regulated products and therefore aimed to determine whether NF-kappaB signalling plays any role in regulating apoptosis. Using Western blotting, we detected that IkappaBalpha becomes phosphorylated immediately following detachment and that levels of phospho-IkappaBalpha peaked within 20 min. Phosphorylation of IkappaBalpha was followed by Rel A (p65) nuclear translocation. Increased NF-kappaB activity following detachment was confirmed using the detection of NF-kappaB-promoted luciferase gene expression delivered by adenovirus infection. Infection of cells with adenovirus expressing a super-repressor IkappaBalpha protein and pharmacological inhibitors of NF-kappaB resulted in the failure to phosphorylate IkappaBalpha, a more rapid activation of caspases and earlier apoptosis. We also detected that IkappaB kinase alpha (IKKalpha) and not IKKbeta became phosphorylated following detachment. Since IKKalpha is activated by NF-kappaB-inducing kinase (NIK), we overexpressed native NIK using an adenovirus vector that resulted in enhanced phospho-IkappaBalpha and nuclear p65 in detached cells compared to control detached cells but did not result in a significantly greater number of cells surviving to 24 h. We conclude that detachment directly activates NF-kappaB, which, in addition to launching an inflammatory cytokine wave, contributes to a delay in apoptosis in intestinal epithelial cells.
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PMID:Activation of NF-kappaB following detachment delays apoptosis in intestinal epithelial cells. 1600 76

Silencing of gene expression by small interfering RNAs (siRNAs) is rapidly becoming a powerful tool for genetic analysis and represents a potential strategy for therapeutic product development. However, there are no reports of systemic delivery for siRNAs toward treatment of bone-metastatic cancer. Accordingly, we report here that i.v. injection of GL3 luciferase siRNA complexed with atelocollagen showed effective reduction of luciferase expression from bone-metastatic prostate tumor cells developed in mouse thorax, jaws, and/or legs. We also show that the siRNA/atelocollagen complex can be efficiently delivered to tumors 24 h after injection and can exist intact at least for 3 days. Furthermore, atelocollagen-mediated systemic administration of siRNAs such as enhancer of zeste homolog 2 and phosphoinositide 3'-hydroxykinase p110-alpha-subunit, which were selected as candidate targets for inhibition of bone metastasis, resulted in an efficient inhibition of metastatic tumor growth in bone tissues. In addition, upregulation of serum IL-12 and IFN-alpha levels was not associated with the in vivo administration of the siRNA/atelocollagen complex. Thus, for treatment of bone metastasis of prostate cancer, an atelocollagen-mediated systemic delivery method could be a reliable and safe approach to the achievement of maximal function of siRNA.
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PMID:Efficient delivery of small interfering RNA to bone-metastatic tumors by using atelocollagen in vivo. 1609 73

Angiogenesis is essential for solid tumor growth. Although successful antiangiogenic therapies have been demonstrated in animal models, a systematic comparison of the efficacy of different antiangiogenic factors has not been described in the hepatic environment. To address this issue, CT26 murine colon carcinoma cells were transfected with retroviral vectors encoding murine endostatin (mEndostatin), human angiostatin (hAngiostatin), murine-soluble vascular endothelial growth factor receptor-2, (msFlk-1), or murine-soluble Tie2 (msTie2). The transfected cells were then subjected to another round of transfection with a luciferase cDNA-encoding retroviral vector. Expression of these putative antiangiogenic proteins inhibited the proliferation of human umbilical vein endothelial cells in vitro but not tumor cells. To examine effects on tumor growth in vivo, modified cells were delivered via intrasplenic injection into BALB/c mice to induce liver metastases. Tumor burden was measured weekly by bioluminescence. Growth of hepatic metastases in vivo was significantly reduced in mice that were administered cells expressing msTie2 (76% reduction compared with control cells 21 days after intrasplenic inoculation; P < 0.05). Similar results were observed with cells that expressed msFlk-1 and hAngiostatin. However, expression of mEndostatin had no significant effect on the growth of liver metastases compared with control animals. These findings indicate that multiple antiangiogenic pathways are necessary for the growth of hepatic metastases, and each of these pathways is a potential clinically relevant antiangiogenic target for the treatment of this disease.
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PMID:A comparison of antiangiogenic therapies for the prevention of liver metastases. 1624 20

KiSS-1 has been shown to function as a tumor metastasis suppressor gene and reduce the number of metastases in different cancers. The expression of KiSS-1 or KiSS1, like other tumor suppressor, is commonly reduced or completely ablated in a variety of cancers via an unknown mechanism. Here we show that the loss of KiSS-1 expression in highly metastatic breast cancer cell lines correlates directly with the expression levels of two transcription factors, activator protein-2alpha (AP-2alpha) and specificity protein 1 (Sp1), which synergistically activate the transcriptional regulation of KiSS-1 in breast cancer cells. Although the KiSS-1 promoter contains multiple AP-2alpha binding elements, AP-2alpha-mediated regulation occurs indirectly through Sp1 sites, as determined by deletion and mutation analysis. Overexpression of AP-2alpha into highly metastatic breast cell lines did not alter KiSS-1 promoter-driven luciferase gene activity. However, co-transfection of AP-2alpha wild-type or the dominant negative form of AP-2 lacking its C-terminal DNA-binding domain, AP-2B, together with Sp1, increased KiSS-1 promoter activity dramatically, suggesting that AP-2alpha regulation of KiSS-1 transcription does not require direct binding to the KiSS-1 promoter. Furthermore, we demonstrated that AP-2alpha directly interacted with Sp1 to form transcription complexes at two tandem Sp1-binding sites of the promoter to activate KiSS-1 transcription. Together, our results indicate that AP-2alpha and Sp1 are strong transcriptional regulators of KiSS-1 and that loss or decreased expression of AP-2alpha in breast cancer may account for the loss of tumor metastasis suppressor KiSS-1 expression and thus increased cancer metastasis.
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PMID:Regulation of KiSS-1 metastasis suppressor gene expression in breast cancer cells by direct interaction of transcription factors activator protein-2alpha and specificity protein-1. 1626 Apr 18

The invasive and metastatic potentials of hepatocellular carcinoma (HCC) are positively correlated with the expression level of alpha3beta1 integrin, a high-affinity adhesion receptor for laminin isoforms. Transforming growth factor (TGF)-beta1 stimulates non-invasive HCC cells to acquire invasive phenotypes in association with the enhanced expression of alpha3 integrin. In this study, we investigated the molecular mechanism underlying the upregulation of alpha3beta1 integrin by TGF-beta1 in non-invasive HepG2 HCC cells. The treatment of HepG2 cells with TGF-beta1 induced the expression of alpha3 integrin and potentiated these cells to adhere to laminin-5 and to migrate through laminin-5-coated membranes. The promoter activity was measured by luciferase assay with a series of deletion constructs of the 5'-flanking region of the mouse alpha3 integrin gene, and the results showed that the -260/-119 region (relative to the major transcription start site) contained elements responsive to TGF-beta1 stimulation. The introduction of mutations into the putative consensus binding sequence for the Ets-family of transcription factors located at -133 greatly decreased the promoter activity responding to TGF-beta1 stimulation. The nuclear proteins extracted from TGF-beta1-stimulated HepG2 cells yielded a larger amount of DNA-nuclear protein complexes than did those extracted from unstimulated cells, as determined by an electrophoretic mobility shift assay using an oligonucleotide containing the Ets-site as a probe. These results suggest that TGF-beta1 stimulates HepG2 cells to express a higher level of alpha3 integrin by transcriptional upregulation via Ets transcription factors and to exhibit a more invasive phenotype.
Clin Exp Metastasis 2005
PMID:Transforming growth factor-beta1 upregulates transcription of alpha3 integrin gene in hepatocellular carcinoma cells via Ets-transcription factor-binding motif in the promoter region. 1647 24

Bioluminescence imaging (BLI) has greatly facilitated the development of animal models of cancer, allowing sensitive detection of luciferase-expressing cancer cells in living mice. Previous efforts characterizing such models have involved small numbers of animals, limiting understanding of their performance features. We employed BLI to serially image the growth and distribution of a prostate cancer cell line, 22Rv1, after intracardiac injection into scid mice (n = 85). This approach models hematogenous dissemination of cancer cells and allows inquiry of the process of metastatic colonization at various organ sites, although accurately injecting cancer cells into the left ventricle remains challenging. Therefore, to predict injection success we measured the ratio of the thoracic bioluminescence signal to the whole body bioluminescence signal (T/WB ratio) immediately following intracardiac injection. A T/WB ratio less than 0.50 predicted the development of tumors outside of the thoracic cavity while a T/WB greater than 0.50 predicted the development of tumors entirely within the thoracic cavity, suggestive of a failed injection. Progressive tumor growth was quantified using BLI. Tumors colonized multiple organ sites including bone, liver, and adrenal glands resembling the spectrum of metastases in autopsy studies of patients with prostate cancer. Tumors growing in bone exhibited mixed osteolytic and osteoblastic features, eliciting a spiculated periosteal response. With the ability to more accurately predict injection success, we can now monitor efficacy of intracardiac injections facilitating the performance of this model.
Clin Exp Metastasis 2005
PMID:Assessing tumor growth and distribution in a model of prostate cancer metastasis using bioluminescence imaging. 1670 13

The pathogenesis of bone metastases may require the activation of osteoclasts by tumor-secreted factors, which promote important interactions with the bone microenvironment. We utilized an intratibial model of bone metastasis with bioluminescent imaging (BLI) to measure the effect of osteoclast inhibition on the interaction of human lung cancer cells with bone, and on tumor growth. Mice were injected with luciferase-transduced tumor cells (HARA, human pulmonary squamous carcinoma) and divided into three groups: (1) untreated, (2) twice weekly treatment with the bisphosphonate zoledronic acid (ZOL), or (3) osteoprotegerin (OPG). Histomorphometry and imaging were used to evaluate tumor burden, and parameters of osteoclast activity. Mice in the treated groups had increased bone density and decreased osteoclast numbers in nontumor-bearing tibiae. There was greater than 60% reduction in mean tumor volume in both treatment groups when evaluated by histomorphometry (P = 0.06 [OPG], P = 0.07 [ZOL]). However, bioluminescent imaging failed to show a reduction in tumor burden due to wide variability in the data. Osteoclast numbers along tumor-associated bone were significantly increased compared to tumor-free bone, and were not reduced by either treatment. Plasma calcium concentration was increased in all groups. Plasma tartrate-resistant acid phosphatase 5b was reduced in both treatment groups. Plasma PTHrP was significantly increased in the untreated tumor-bearing group, but was not significantly different in the two treatment groups compared to normal mice. OPG or ZOL did not change tumor cell proliferation, but ZOL increased HARA cell apoptosis. OPG and ZOL reduced tumor growth in the tibiae of treated mice, however, PTHrP production by HARA cells may have resulted in a high concentration in the bone microenvironment, partially overriding the antiosteoclast effects of both OPG and ZOL.
Clin Exp Metastasis 2006
PMID:The effect of zoledronic acid and osteoprotegerin on growth of human lung cancer in the tibias of nude mice. 1671 52

We recently established a mouse model of peritoneal dissemination of human gastric carcinoma, including the formation of ascites, by orthotopic transplantation of cultured gastric carcinoma cells. To clarify the processes of expansion of the tumors in this model, nude mice were sacrificed and autopsied at different points of time after the orthotopic transplantation of the cancer cells for macroscopic and histopathologic examination of the tumors. The cancer cells grew actively in the gastric submucosa and invaded the deeper layers to reach the serosal plane. The tumor cells then underwent exfoliation and became free followed by the formation of metastatic lesions initially in the greater omentum and subsequent colonization and proliferation of the tumors on the peritoneum. Although this model allowed the detection of even minute metastases, it was not satisfactory from the viewpoint of quantitative and objective evaluation. To resolve these problems, we introduced a luciferase gene into this tumor cell line with a high metastasizing potential and carried out in vivo photon counting analysis. This photon counting technique was found to allow objective and quantitative evaluation of the progression of peritoneal dissemination on a real-time basis. This animal metastatic model is useful for monitoring the responses of tumors to anticancer agents.
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PMID:A photon counting technique for quantitatively evaluating progression of peritoneal tumor dissemination. 1688 51

A limited number of in vivo models that rapidly assess bone development or allow for the study of tumor progression in a closed in vivo environment exist. To address this, we have used bone tissue engineering techniques to generate a murine in vivo bone bioreactor. The bioreactor was created by implanting an osteoconductive hydroxyapatite scaffold pre-loaded with saline as a control or with bone morphogenetic protein-2 (BMP-2) to the murine femoral artery. Control and BMP-2 bioreactors were harvested and histologically assessed for vascularization and bone formation at 6 and 12 weeks post implantation. BMP-2 significantly enhanced the formation of osteoid within the bioreactor in comparison to the controls. To test the in vivo bone bioreactor as a model of tumor: bone interaction, FVB mice were implanted with control or BMP-2 treated bioreactors. After 6 weeks, an osteolytic inducing mammary tumor cell line tagged with luciferase (PyMT-Luc) derived from the polyoma virus middle T (PyMT) model of mammary tumorigenesis was delivered to the bioreactor via the femoral artery. Analysis of luciferase expression over time demonstrated that the presence of osteoid in the BMP-2 treated bioreactors significantly enhanced the growth rate of the PyMT-Luc cells in comparison to the control group. These data present a unique in vivo model of ectopic bone formation that can be manipulated to address molecular questions that pertain to bone development and tumor progression in a bone environment.
Clin Exp Metastasis 2006
PMID:The application of a murine bone bioreactor as a model of tumor: bone interaction. 1713 74


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