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)

Orthotopic or intracardiac injection of human breast cancer cell lines into immunocompromised mice allows study of the molecular basis of breast cancer metastasis. We have established a quantitative real-time PCR approach to analyze metastatic spread of human breast cancer cells inoculated into nude mice via these routes. We employed MDA-MB-231 human breast cancer cells genetically tagged with a bacterial beta-galactosidase (Lac-Z) retroviral vector, enabling their detection by TaqMan real-time PCR. PCR detection was linear, specific, more sensitive than conventional PCR, and could be used to directly quantitative metastatic burden in bone and soft organs. Attesting to the sensitivity and specificity of the PCR detection strategy, as few as several hundred metastatic MDA-MB-231 cells were detectable in 100 microns segments of paraffin-embedded lung tissue, and only in samples adjacent to sections that scored positive by histological detection. Moreover, the measured real-time PCR metastatic burden in the bone environment (mouse hind-limbs, n = 48) displayed a high correlation to the degree of osteolytic damage observed by high resolution X-ray analysis (r2 = 0.972). Such a direct linear relationship to tumor burden and bone damage substantiates the so-called 'vicious cycle' hypothesis in which metastatic tumor cells promote the release of factors from the bone which continue to stimulate the tumor cells. The technique provides a useful tool for molecular and cellular analysis of human breast cancer metastasis to bone and soft organs, can easily be extended to other cell/marker/organ systems, and should also find application in preclinical assessment of anti-metastatic modalities.
Clin Exp Metastasis 2002
PMID:Correlation between extent of osteolytic damage and metastatic burden of human breast cancer metastasis in nude mice: real-time PCR quantitation. 1219 65

The pleura covers the lung parenchyma, chest wall, and diaphragm with a single layer of flat cells that are easy to genetically modify with adenovirus (Ad) vectors. Although intrapleural gene therapy has been used to treat intrapleural disorders, we hypothesized that it may also be used to deliver extracellular gene products to the lung parenchyma. In this context, this study is based on the concept that administration of adenovirus gene transfer vectors into the pleural cavity will mediate expression of gene products in mesothelial cells, and that the extracellular products produced by these genetically modified cells will reach the lung parenchyma. To assess this concept, Ad(beta)gal (expressing beta-galactosidase [beta-Gal]) or AdLuc (expressing luciferase) was administered into the right pleural cavity of BALB/c mice, as compared with intravenous injection via the jugular vein or the intratracheal route. Histologic assessment of lungs and pleural surface after intrapleural administration of Ad(beta)gal demonstrated beta-Gal expression limited to the pleural mesothelium and cells adjacent to the pleural surface. Right intrapleural administration of AdLuc showed higher level of luciferase in both the right and left lung (right vs. left, p > 0.8), compared with the intratracheal (p < 0.05) or intravenous routes (p < 0.02), that is, unilateral intrapleural administration is sufficient to transfer genes bilaterally to the pleura. To assess the ability of intrapleural gene transfer to modify lung parenchymal processes, CT26.CL25 tumor cells (3 x 10(5)) were injected via the jugular vein to generate tumor metastases in the lung parenchyma followed 24 hr later by administration to the right pleura of 5 x 10(8) PFU of Adsflt (an Ad "antiangiogenesis" vector expressing a soluble, secreted, extracellular portion of the Flt-1 receptor for vascular endothelial growth factor). Compared with phosphate-buffered saline, or the control vector AdNull (no transgene), mice receiving Adsflt by the intrapleural route had a marked suppression of tumor growth in the parenchyma of both lungs as assessed 12 days after tumor administration (p < 0.005). Treatment of preestablished lung metastases with Adsflt administered by the intrapleural route significantly improved long-term survival as compared with control animals (p < 0.0001). Thus, although intrapleural administration of an Ad vector encoding an intracellular protein mediates gene expression only in mesothelial cells and the local tissues, intrapleural delivery of a vector expressing a secreted protein can be used to modify processes throughout the lung parenchyma. In the context that intravascular gene transfer is an ineffective strategy to deliver gene products to the lung parenchyma, and that intratracheal administration is associated with alveolar inflammation secondary to host defenses against Ad vectors, these findings demonstrate that intrapleural administration represents a strategy that can be used to effectively deliver extracellular gene products to the lung parenchyma via a site that is readily accessible, and where inflammation against the vector will not have significant pathophysiologic consequences.
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PMID:Gene transfer to the pleural mesothelium as a strategy to deliver proteins to the lung parenchyma. 1221 68

Melanoma incidence is growing at a faster rate than any other human malignancy. Wild-type (wt) p53 is important in both G(1) and G(2) cell cycle arrest, and cyclin D1 (CD1) is necessary for G(1)-->S progression in melanoma cells. We reported that an adenoviral vector containing wt p53 significantly reduced [(3)H]thymidine uptake in melanoma cells containing mutant but not wt p53. Subsequently we showed that CD1 decreased melanoma proliferation and increased apoptosis. We now extend these findings by evaluating the effect on preformed melanomas of (1) intratumoral therapy with wt p53 alone, (2) wt p53 in combination with antisense (AS) CD1, both short (< or =14 days) and longer term, and (3) doubling the dose or repeat doses of wt p53 or AS CD1. Two melanoma cells lines that metastasize in SCID mice (451 and 1205) were used, one containing a p53 mutation (451) and the other a normal p53 gene sequence (1205). Compared to injection with a control adenoviral vector containing beta-galactosidase (LacZ), intratumoral injection of wt p53 slowed the growth of tumors formed from 451 cells. Using 5 x 10(8) plaque forming units as our standard intratumoral dose, neither doubling the dose of LacZ, p53 or AS CD1, nor repeat doses of the vectors, was as effective as combined therapy with wt p53+AS CD1, which resulted in the shrinkage of all tumors treated and 4/7 (57%) tumors vanished. No tumors treated with wt p53 or AS CD1 alone vanished. Wt p53+AS CD1 treatment resulted in significantly more cells undergoing apoptosis compared to either therapy alone. In summary, combining the separately effective treatment vectors p53 and AS CD1 led to an enhanced growth-suppressive and apoptotic effect, supporting a role for combination gene therapy to treat human malignant melanoma.
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PMID:p53 alone or in combination with antisense cyclin D1 induces apoptosis and reduces tumor size in human melanoma. 1222 20

Our previous studies conducted in pancreatic cancer models established in nude mice and hamsters revealed that cloned somatostatin receptor subtype 2 (sst2) gene expression induced both antioncogenic and local antitumor bystander effects in vivo. In the present study, in vivo gene transfer of sst2 was investigated in two transplantable models of primary and metastatic pancreatic carcinoma developed in hamsters. LacZ reporter or mouse sst2 genes were expressed by means of two different delivery agents: an adenoviral vector and a synthetic polycationic carrier [linear polyethylenimine (PEI)]. sst2 was injected into either exponentially growing pancreatic primary tumors or hepatic metastases, and then transgene expression and tumor progression were investigated 5-6 days after gene transfer. Molecular mechanisms involved in the inhibition of tumor growth were also analyzed. Both adenovirus- and PEI-mediated in vivo gene transfer in primary pancreatic tumors induced an increase of beta-galactosidase activity and expression of sst2 transgene nRNA (100% and 86% of tumors for adenovirus and PEI vector, respectively). Adenoviral vector-based sst2 gene transfer resulted in significant reduction of pancreatic tumor growth (P < 0.05). Using PEI vector, both pancreatic primary tumor growth and metastatic tumor growth were also significantly slackened as compared with both LacZ-treated and untreated control groups (P < 0.02). Moreover, the proliferative index decreased significantly (P < 0.005), whereas apoptosis increased (P < 0.005) in tumors transferred with sst2 gene. The increase of apoptosis correlated with an activation of the caspase-3 and poly(ADP-ribose) polymerase pathways. We concluded that in both primary and metastatic pancreatic cancer models, the synthetic gene delivery system can achieve in vivo sst2 gene transfer and results in a significant antitumor effect characterized by an increase of apoptosis and an inhibition of cell proliferation. This new strategy of gene therapy allows the restoration of expression of an antioncogenic molecule and could be promising for the treatment of advanced pancreatic cancer.
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PMID:Antitumor effect of in vivo somatostatin receptor subtype 2 gene transfer in primary and metastatic pancreatic cancer models. 1241 37

To elicit a therapeutic antitumor immune response, dendritic cells (DCs) have been employed as a cellular adjuvant. Among various DC-based approaches, fusion of DCs and tumor cells potentially confers not only DC functionality, but also a continuous source of unaltered tumor antigens. We have recently demonstrated successful generation of fusion hybrids by a large-scale electrofusion technique. The immunogenicity and therapeutic potential of fusion hybrids were further analyzed in a model system of a murine melanoma cell line expressing beta-galactosidase (beta-gal) as a surrogate tumor antigen. A single vaccination with fusion hybrids plus IL-12 induced a therapeutic immune response against 3-day established pulmonary metastases. This immunotherapy was beta-gal specific and involved both CD4 and CD8 T cells. In vitro, fusion hybrids stimulated specific IFN-gamma secretion from both CD4 and CD8 immune T cells. They also nonspecifically induced IL-10 secretion from CD4 but not CD8 T cells. Compared to other DC loadings, our results demonstrate the superior immunogenicity of fusion. The current technique of electrofusion is adequately developed for clinical use in cancer immunotherapy.
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PMID:Therapeutic immune response induced by electrofusion of dendritic and tumor cells. 1271 34

Specific targeting and transgene expression in tumors are critical in adenovirus gene therapy for intrahepatic colon carcinoma metastases. In this study, we investigated if ionizing radiation could increase adenoviral uptake by cells. Various human cell lines and rat hepatocytes were irradiated prior to exposure to a cytomegalovirus (CMV) promoter-driven green fluorescent protein (GFP) marker gene adenoviral vector. We found that gamma-radiation increased the number of GFP-positive cells in a dose- and time-dependent manner for most cells, ranging from 4.6- to 27.1-fold after a 4-Gy treatment. No induction occurred for lentiviral vector, lipofection, or naked plasmid exposure. Preincubation of cells with adenovirus failed to show an increase, suggesting that radiation might mediate adenoviral infection by inducing viral uptake into cells. We demonstrated that radiation induced internalization of a fluorescence-labeled adenovirus (Cy3-Ad) and an increase in intracellular viral DNA content. Rats bearing intrahepatic colon carcinoma xenografts were irradiated in the tumor region followed by portal venous administration of an adenoviral vector containing a CMV-beta-galactosidase (beta-gal) gene. Radiation increased beta-gal activity in tumors as much as 5.4-fold after a 25-Gy treatment. These data suggest that a combination of regional radiation treatment with adenovirus gene therapy is a rational strategy for improving adenoviral targeting and transgene expression in tumors.
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PMID:Ionizing radiation increases adenovirus uptake and improves transgene expression in intrahepatic colon cancer xenografts. 1284 25

Tamoxifen has contributed to a dramatic reduction in breast cancer mortality and recent results indicate that aromatase inhibitors may further improve survival in some patients. Nevertheless, a substantial proportion of patients become resistant to treatment. To date, with the exception of estrogen receptor (ER) determination by ligand binding or immunohistochemical techniques, there has been no way of predicting which of several therapies is indicated in particular patients. We describe a novel assay using the adenoviral gene delivery system to assess ER function in breast cancer cells derived directly from patients. The purification and short-term culture of these cells has been recently described by our laboratory. Adenovirus containing an estrogen-regulated beta-galactosidase reporter gene (ERE-lacZ) was constructed and used to test ER activity in breast cancer cells derived from 18 patients with primary and 16 patients with metastatic cancer, under varying treatment schedules. The adenoviral assay enabled ER activity to be readily determined in purified cells from primary breast cancers and secondary sites. Breast cancers cells could be categorized on the basis of ER activity in the absence of ligand, the presence of estrogen or anti-estrogens. In primary breast cancers, our results correlated with ER determination by immunohistochemistry in 78% of cases. In patients who had become resistant to tamoxifen, however, we found some in whom reporter activity was stimulated by tamoxifen and others whose tumors were either still estrogen responsive or completely unresponsive, irrespective of the original ER content. Our findings indicate that this reporter assay could be useful in decisions regarding use of adjuvant endocrine therapies in breast cancer.
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PMID:Reporter gene assay demonstrates functional differences in estrogen receptor activity in purified breast cancer cells: a pilot study. 1456 18

We developed a model system for testing gene vectors, based on the growth of murine tumors on the chorioallantoic membrane (CAM) of embryonic chickens. The ability of selected murine cells to grow on the CAM was rated according to the following criteria: i) formation of tumor masses; ii) metastasis formation; iii) reproducibility; iv) yield, indicated as the number of embryos surviving to assessment time with visible tumors on the CAM; v) maintainability of the cell, both in the original host and the embryonic chick, or 'shuttle maintainability'; vi) detection by the naked eye, and vii) cost/benefit relation. The murine melanoma cell lineage, B16F10, which efficiently forms distinct, pigmented tumor masses and metastases on the CAM, performed better in this model than the murine B61 cell line. In vitro transduction of B16F10 cells with a recombinant adenovirus carrying a construct of the E. coli LacZ gene followed by inoculation onto the CAM resulted in beta-galactosidase expression in the tumor mass growing on the CAM. This model is potentially applicable to preclinical evaluation of gene vectors, especially for gene therapy of cancer.
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PMID:A model system for testing gene vectors using murine tumor cells on the chorioallantoic membrane of the chick embryo. 1496 44

The Arguello model of cancer metastasis to bone has been used extensively to study breast cancer-induced osteolytic disease. The effects of therapy on skeletal disease and on tumour burden in soft organs are traditionally measured using radiography and/or time-consuming histomorphometry, respectively. The purpose of this study was to develop a sensitive and efficient method for evaluating tumour burden in vivo using MDA-231 cells transduced with the E. coli lacZ gene (MDA-231BAG). Osteolysis was measured by radiography and tumour burden was measured histomorphometrically or biochemically. In untreated mice, measurements of tumour burden in bone extracts using human cytokeratin-associated tissue polypeptide antigen (TPA) ELISA or E. coli beta-galactosidase (beta-gal) activity immunoassay reflected the extent of osteolytic disease as measured by radiography; however, tumour load could be detected before onset of osteolysis. When monitoring the effect of therapy (0.2 mg/kg ibandronate/day), radiography alone proved to be insufficient. Mice treated with the bisphosphonate ibandronate from time of inoculation with cancer cells had no radiologically visible signs of osteolysis but significant tumour load was measured in the bone extracts using these assays. Furthermore, beta-gal activity could be used as a measurement of tumour load in soft organs, and unlike other human breast cancer markers expressed by the MDA-231 cells in vitro, beta-gal activity was detected in the serum of mice with progressive disease. In conclusion, we describe an efficient model of breast cancer-induced osteolysis to quantify the effect of therapy on disease load and distribution, which could be beneficial in evaluating novel therapies for the treatment of the disease.
Clin Exp Metastasis 2004
PMID:Measurement of tumor load and distribution in a model of cancer-induced osteolysis: a necessary precaution when testing novel anti-resorptive therapies. 1506 4

Dendritic cells (DC) represent a potential target for gene therapy. In their ability to process antigens and present them to T cells, DC have been allocated a unique role as initiators of the immune response in both the innate and acquired immunity. Recent in vitro studies have showed the feasibility of DC transduction with adenoviral recombinants. In cancer therapy, targeting of DC with adenovirus has been proved to be effective in inhibiting tumour growth, as well as in reducing the number of tumour metastases. The aim of our study is to evaluate the feasibility of in vivo transduction of DC in a murine lymphocyte-rich compartment (thymus) as a potential treatment for acute inflammatory diseases. Nearly 50% of the total thymic DC were transduced with a first-generation adenoviral construct following intrathymic injection, and post-transductional inflammation was neglectable. Transduction of thymic cells with adenoviral recombinants was able to induce the expression of an intracellular protein (beta-galactosidase, green fluorescent protein), as well as the secretion of human interleukin-10, within the local compartment. Furthermore, this induction of the latter significantly decreased thymic apoptosis in the applied model of acute bacterial peritonitis (cecal ligation and puncture).
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PMID:In vivo transduction of thymic dendritic cells with adenovirus and its potential use in acute inflammatory diseases. 1585 12


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