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)

Oncolytic herpesviruses have significant antitumoral effects in animal models when delivered directly to established tumors. Lymphatic metastases are a common occurrence for many tumor types. This study investigates the potential of an attenuated, replication-competent, oncolytic herpes simplex virus (NV1023) both to treat a primary tumor by direct injection and to travel through the lymphatic system to treat metastatic tumor within the lymph nodes draining lymph from the site of primary cancer. Isosulfan blue dye was injected into murine auricles to determine normal lymphatic drainage patterns and demonstrated consistent blue staining of a group of ipsilateral cervical lymph nodes. Auricular injections of NV1023 resulted in viral transit to these lymph nodes as measured by 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside histochemistry and viral plaque assay. An oncolytic herpesvirus (NV1066) expressing green fluorescent protein also demonstrated viral transit from the auricle to the cervical lymph nodes on fluorescence microscopy. Using the SCC VII cell line, a novel murine model of auricular squamous cell carcinoma was developed with an approximately 20% incidence of cervical lymph node metastases. Delivery of NV1023 or NV1066 to the surgical beds after excision of auricular SCC VII tumors resulted in successful viral infection of metastatic SCC VII cells within the cervical lymph nodes. After a 7-week follow-up, significantly enhanced locoregional control (p < 0.05, Fisher exact test) and disease-free survival (p < 0.05, log rank test) were evident with NV1023 treatment. This study demonstrates that the delivery of an oncolytic herpesvirus to a primary tumor site after surgical excision may have a significant impact on reducing both primary site recurrence and regional nodal metastases.
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PMID:Oncolytic herpesvirus effectively treats murine squamous cell carcinoma and spreads by natural lymphatics to treat sites of lymphatic metastases. 1213 74

Gene therapy for cancer using suicide genes such as the herpes simplex virus thymidine kinase gene (HSVtk) has been explored extensively in preclinical and clinical studies. We have improved the use of HSVtk by combining it with two cytokine genes encoding granulocyte/macrophage-colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2), and determined their additive/synergistic effects on tumor regression and inhibition of metastases in the non-immunogenic, spontaneously metastatic mammary tumor model, 4T1. Two adenoviral vectors (AV) were constructed, one carrying HSVtk (AV-TK) and the second (AV-GM/IL2) carrying Gm-CSf and Il2. Only the combination of AV-TK/GCV and AV-GM/IL2 showed a significant decrease in tumor growth and reduction of distant metastases with 25% of the tumors undergoing complete regression. When surgical excision of primary tumors was included in the regimen, local treatment with AV-TK/GCV plus AV-GM/IL2 further enhanced long-term survival. A fraction of the treated mice developed anti-tumor immunity and survived a second challenge with 4T1. Functional analyses demonstrated infiltration of lymphocytes within the tumor and a strong tumor-specific cytotoxic T lymphocyte response in TK- plus cytokine-treated animals. These data indicate that the coexpression of GM-CSF and IL-2 can augment the effect of HSVtk suicide gene therapy.
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PMID:Development of anti-tumor immunity against a non-immunogenic mammary carcinoma through in vivo somatic GM-CSF, IL-2, and HSVtk combination gene therapy. 1240 61

We previously demonstrated significant therapeutic activities associated with adenoviral vector-mediated Herpes Simplex Virus/thymidine kinase (AdHSV-tk) with ganciclovir (GCV) in situ gene therapy in the RM-1 orthotopic mouse prostate cancer model and interleukin-12 (AdmIL-12) in situ gene therapy in the RM-9 orthotopic mouse prostate model for prostate cancer. In both protocols, local cytotoxicity and activities against pre-established lung metastases were demonstrated. To test whether combined AdHSV-tk+GCV+IL-12 gene therapy would lead to enhanced therapeutic effects when compared to either treatment alone, we used RM-9 mouse prostate cancer cells in both orthotopic and pre-established lung metastases models of prostate cancer. Combined treatment with a single injection of optimal doses of AdHSV-tk+GCV or AdmIL-12 led to significantly increased suppression of orthotopic tumor growth. IL-12 gene therapy alone was more effective than AdHSV-tk+GCV in suppressing spontaneous lymph node metastases and pre-established lung metastases but combination gene therapy did not result in additional anti-metastatic activities. Combination gene therapy also did not achieve significantly better animal survival compared to AdHSV-tk+GCV or AdmIL-12 alone. Analysis of localized antitumor activities demonstrated that AdHSV-tk+GCV therapy induced higher levels of necrosis compared to AdmIL-12 or combination therapy. However, both treatments alone and combination therapy produced similar increases in apoptotic index. To address the possible mechanisms of locally co-operative cytotoxic activities, we analyzed the systemic natural killer (NK) response and the numbers of tumor-infiltrating immune cells using quantitative immunohistochemical analysis. AdHSV-tk+GCV therapy alone led to detectable increases in iNOS-positive cells, CD4+and CD8+T-cells and moderately increased numbers of F4/80 (macrophage selective)-positive cells within treated tumors. In contrast, AdmIL-12 elicited a highly robust pattern of tumor infiltration for all four of these immune cells that was in general mimicked by combination therapy. Further analysis of the accumulation of transforming growth factor-beta1 (TGF-beta1) immunohistochemical staining demonstrated that AdHSV-tk+GCV treatment, but not AdmIL-12 treatment, produced cancer cell-associated increases in this cytokine relative to control Ad-beta-gal injections. Interestingly, local injection with AdHSV-tk+GCV induced significant splenocyte-derived NK cell cytolytic activities with maximal response 7 days following treatment, whereas AdmIL-12 injection produced significantly higher NK activity with maximal response 2 days following injection. The combined treatment produced a higher systemic NK response over the 14-day treatment period. Depletion of NK cells in vivo demonstrated that this immunocyte subpopulation was responsible for early locally cytotoxic activities induced by AdHSV-tk+GCV but not AdmIL-12 and that NK activities were largely responsible for activities against pre-established metastases generated by both gene therapy protocols. Prostate Cancer and Prostatic Diseases (2001) 4, 44-55
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PMID:Combination gene therapy with adenoviral vector-mediated HSV-tk+GCV and IL-12 in an orthotopic mouse model for prostate cancer. 1249 62

The most serious problem in current gene therapy is discrepancies between experimental data and actual clinical outcomes, which may be due to insufficient analyses and/or inappropriate animal models. We have explored suicide gene therapy by using various clinically relevant animal models and doubt the clinical use of maximal suicide gene expression, which has been generally recommended. To explore this subject further, we studied what expression level of suicide gene and what promoter led to the maximal clinical benefit in the case of hepatic metastatic cancer in mice. Therapeutic and adverse side effects of 4 adenoviral vectors that express herpes simplex virus thymidine kinase (HSV-tk) under different promoters were scrupulously investigated in 2 mouse models of hepatic metastasis of gastric cancer that possess clinical characteristics. Surprisingly, increases in HSV-tk expression beyond a certain point, achieved by the Rous sarcoma virus long terminal repeat promoter, not only enhanced the adverse side effects of lethal hepatotoxicity and ganciclovir-independent cytotoxicity but also failed to further increase therapeutic potential. Moreover, the carcinoembryonic antigen (CEA) tumor-specific promoter, the therapeutic potential of which had been underestimated, was much more useful-even in the case of low CEA-producing cancer-than had been previously reported. In conclusion, the optimal therapeutic expression level of a suicide gene is a novel concept and a crucial factor for successful cancer gene therapy. The present results, which contradict those of previous studies, alert researchers about possible problems with ongoing and future clinical trials that lack this concept.
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PMID:An optimal therapeutic expression level is crucial for suicide gene therapy for hepatic metastatic cancer in mice. 1250 Feb

Stromal-epithelial interaction contributes to local prostate tumor growth, androgen-independent progression and distant metastasis. We have established in vitro coculture and in vivo chimeric tumor models to evaluate the roles of stromal cells isolated from either osteosarcoma or normal bone, a site where prostate cancer cells frequently metastasize, in contributing to the growth and survival of human prostate cancer cells. We have evaluated extensively the effects of toxic gene therapy using luciferase-tagged chimeric human prostate cancer models both in vitro and in vivo. In the in vitro cocultured cell model, we assessed cancer cell growth and residual cellular proteins after targeting either prostate cancer epithelial cells alone or both prostate cancer and bone stromal cells. In the in vivo animal model, we measured tumor volume and serum prostate-specific antigen (PSA) in mice bearing chimeric prostate tumors comprised of human prostate tumor cells and normal bone stromal cells. Our results demonstrated that: (1) The rate of human prostate cancer cell growth in vitro is accelerated by coculturing with human and rat osteosarcoma or normal mouse bone marrow stromal cell lines. No growth stimulation was noted when cocultured with a human prostate epithelial cell line. (2) Disabling the growth of normal bone stromal cells using transgenic targeting with a bystander gene, herpes simplex virus thymidine kinase (hsv-TK), plus the pro-drug ganciclovir (GCV) or acyclovir markedly depressed the growth of cocultured human prostate cancer cells in vitro and human prostate cancer-mouse normal bone stroma chimeric tumors in vivo. (3) By cotargeting both human prostate cancer and normal mouse bone stromal cells in vitro with an adenoviral construct, Ad-hOC-TK (a replication-defective Ad5 vector with the bystander transgene hsv-TK under the control of a human osteocalcin (hOC) promoter) plus GCV4, we observed greater inhibition of tumor cell growth than by targeting a single cell compartment with Ad-PSA-TK (a vector construct similar to Ad-hOC-TK except that the transgene expression is under regulation by a full-length human PSA promoter). These results, taken together, established a basic principle that cotargeting both tumor and its supporting stroma is more efficacious than targeting a single cell compartment in the treatment of human prostate cancer bone metastasis. This principle can be applied to other clinical conditions of cancer growth where stroma contribute to the overall growth and survival potential of the cancer.
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PMID:Cotargeting tumor and stroma in a novel chimeric tumor model involving the growth of both human prostate cancer and bone stromal cells. 1469 56

Imaging reporter gene expression in living subjects with various imaging modalities is a rapidly accelerating area of research. Applications of these technologies to cancer research, gene therapy, and transgenic models are rapidly expanding. We report construction and testing of several triple fusion reporter genes compatible with bioluminescence, fluorescence and positron emission tomography (PET) imaging. A triple fusion reporter vector harboring a bioluminescence synthetic Renilla luciferase (hrl) reporter gene, a reporter gene encoding the monomeric red fluorescence protein (mrfp1), and a mutant herpes simplex virus type 1 sr39 thymidine kinase [HSV1-truncated sr39tk (ttk); a PET reporter gene] was found to preserve the most activity for each protein component and was therefore investigated in detail. After validating the activities of all three proteins encoded by the fusion gene in cell culture, we imaged living mice bearing 293T cells transiently expressing the hrl-mrfp-ttk vector by microPET and using a highly sensitive cooled charge-coupled device camera compatible with both bioluminescence and fluorescence imaging. A lentiviral vector carrying the triple fusion reporter gene was constructed and used to isolate stable expressers by fluorescence-activated cell sorting. These stable 293T cells were further used to show good correlation (R(2) approximately 0.74-0.85) of signal from each component by imaging tumor xenografts in living mice with all three modalities. Furthermore, metastases of a human melanoma cell line (A375M) stably expressing the triple fusion were imaged by microPET and optical technologies over a 40-50-day time period in living mice. Imaging of reporter gene expression from single cells to living animals with the help of a single tri-fusion reporter gene will have the potential to accelerate translational cancer research.
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PMID:Imaging tri-fusion multimodality reporter gene expression in living subjects. 1497 78

The incidence of prostate cancer has dramatically increased worldwide in the past decade, with mortality rates also increasing in many countries. Once prostate cancer is diagnosed, it is important to rapidly begin a treatment regimen that is either potentially curative or impedes disease progression. When the disease is confined to the prostate, it can be cured by radical prostatectomy or irradiation therapy. However, there are no curative therapies for locally advanced, recurrent, or metastatic diseases. Clearly, new therapies are needed for these patients. Gene therapy may provide additional therapeutic options with the potential to affect both localized and metastatic disease. Virus-mediated transduction of the herpes simplex virus thymidine kinase (HSV-tk) gene transfer, followed by a course of the prodrug ganciclovir (GCV), so-called suicide gene therapy, has been demonstrated by several investigators. The present in situ gene therapy clinical trial for human prostate cancer demonstrated safety, clinical efficacy, and biological effects of antitumor activity. HSV-tk clinical trials for prostate cancer are also ongoing in Japan, the Netherlands, and Mexico. Currently, numerous preclinical studies have reported immunomodulatory cytokine gene therapy, such as interleukin-2, interleukin-12, B7-1 (CD80), B7-2 (CD86) and granulocyte-macrophage colony-stimulating factor. Several clinical studies have been approved that potentially will show that these immunomodulatory gene therapies may generate an effective local and systemic antitumor activity and that should provide options for patients with prostate cancer. We review the multiple issues involved in current in situ gene therapy (gene/immunotherapy), its outcome, and future directions for patients with prostate cancer.
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PMID:In situ gene therapy for prostate cancer. 1563 15

West Nile encephalitis (WNE) has become endemic in the United States since 1999. The clinical spectrum of WNE includes aseptic meningitis, meningoencephalitis, or encephalitis with or without flaccid paralysis. The severity of WNE ranges from asymptomatic serum conversion to severe neurologic deficits or a fatal outcome. Several systemic disorders may present with encephalitis as part of the clinical presentation, for example, Legionnaires' disease, neoplasms with metastases to the central nervous system, Mycoplasma meningoencephalitis, brucellosis, Listeria, Rocky Mountain spotted fever, ehrlichiosis, and malaria. The most common infectious causes of encephalitis that need to be differentiated from WNE include herpes simplex virus 1, meningoencephalitis, and enteroviral meningoencephalitis. We present a case of apparent hepatic encephalopathy secondary to pancreatic carcinoma with liver involvement that presented as hepatic encephalopathy mimicking WNE. We conclude that patients presenting with encephalitis in the summer months should have serum/cerebrospinal fluid serologic studies sent for WNE even if an alternate explanation seems to explain the clinical syndrome.
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PMID:West Nile viral encephalitis mimicking hepatic encephalopathy. 1564 37

Delivery of viral vectors to tumors in the brain is a challenge, especially via systemic administration, which is key to targeting the invasive margins of malignant glioma and the multiple foci of metastatic disease. Like for other cancer therapeutics, the blood-brain barrier or even the blood-tumor barrier significantly limits delivery and efficacy. Blood-brain barrier disruption (BBBD) is one strategy for transiting the cerebrovasculature. G47Delta is a third-generation oncolytic replication-competent herpes simplex virus (HSV) vector, containing deletions of the gamma34.5 and alpha47 genes and an inactivating LacZ insertion in UL39 (ICP6). Intracarotid artery delivery of G47Delta after BBBD with 25% mannitol significantly extended the life of nude mice bearing intracerebral human MDA-MB-435 breast tumors, whereas, G47Delta injection contralateral to the tumor, in the absence of mannitol or mannitol alone had no effect on survival. G47Delta replication was extensive after BBBD, as visualized by X-gal staining. Staining of peripheral organs, lung and liver, was minimal and not altered by BBBD. This is the first demonstration of intracarotid arterial delivery of oncolytic HSV vectors and antitumor efficacy in a mouse model and opens the door to the use of mouse syngenic tumor models and transgenic/knockout animals.
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PMID:Intracarotid delivery of oncolytic HSV vector G47Delta to metastatic breast cancer in the brain. 1564 62

Gene therapy of cancer offers the possibility of a targeted treatment that destroys tumors and metastases, but not normal tissues. In gene-directed enzyme prodrug therapy (GDEPT), or suicide gene therapy, the gene encoding an enzyme is delivered to tumor cells, followed by administration of a prodrug, which is converted locally to a cytotoxin by the enzyme. The producer cells as well as surrounding bystanders are subsequently killed. Promising results have meant that suicide gene therapy has reached multicenter phase III clinical trials. This review will discuss the development, efficiency, mode of action and pharmacokinetics of seven GDEPT systems in vitro and in vivo. We will review the latest data of those systems in clinical trials (herpes simplex virus thymidine kinase/gancyclovir, bacterial cytosine deaminase/5-fluorocytosine, bacterial nitroreductase/CB1954 and cytochrome P450/cyclophosphamide), as well as the development of more recent and experimental systems which are not yet in clinical trials (P450 reductase/tirapazamine, carboxypeptidase/CMDA, horseradish peroxidase/indole-3-acetic acid or paracetamol and others).
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PMID:From bench to bedside for gene-directed enzyme prodrug therapy of cancer. 1574 71


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