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)

Adoptive transfer of tumour-specific T lymphocytes loaded with ricin into tumour-bearing mice exerts a transient therapeutic effect against locally induced tumours [Cerundolo et al. (1987) Br J Cancer 55: 413]. As transferred cells preferentially locate in the lung, we studied the therapeutic effect of ricin-loaded, lymphokine-activated killer (LAK) cells on lung metastases induced by M4 or B16-F1 (F1) tumour cell injection. In vitro studies demonstrated that ricin-treated LAK cells were about 100-fold more efficient than untreated LAK cells in inhibiting growth of the ricin-sensitive M4 tumour cell line. This effect was most likely due to the released ricin, as treated and untreated LAK cells inhibited the relatively toxin-resistant F1 cell line to the same extent. Ricin treatment did not alter the tissue distribution of intravenously (i.v.) injected LAK cells, which selectively localized in the lung early after inoculation, whether or not metastases were present. Adoptive transfer experiments showed that ricin-treated LAK cells were significantly more efficient than untreated LAK cells in inhibiting M4- but not F1-induced lung metastases. These results indicate that LAK cells are able to deliver a therapeutic concentration of antineoplastic compounds directly to the lung.
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PMID:Antitumour efficacy of lymphokine-activated killer cells loaded with ricin against experimentally induced lung metastases. 161 20

Adoptive transfer of specifically sensitized lymphoid cells constitutes a potential tool for specific cancer immunotherapy, however, the requirement of syngeneic or autologous specifically reactive cells has limited its use in the treatment of human cancer. In several mouse tumor models, large amounts of lymphokine activated killer (LAK) cells associated with high doses of interleukin 2 (IL-2) are able to mediate the regression of established pulmonary and hepatic metastases. Since LAK cells are more easily generated than specifically sensitized lymphocytes and show broad tumor specificity, this approach has been applied in humans to treat cancer, but the acute toxicity associated with the high doses of IL-2 administered represents an important drawback to its clinical use. The observation that lymphocytes can internalize ricin, a toxic plant protein, and then release it in an active form, capable of destroying other cells, led us to investigate the possibility of using antigen-specific cytotoxic T lymphocytes (CTL) or LAK cells as carriers of toxic substances to the tumor site. In our experimental models we observed that tumor-specific CTL or LAK cells can be used to deliver ricin into the tumor mass and cause temporary tumor growth inhibition.
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PMID:Adoptive immunotherapy of experimental tumors using cytotoxic lymphocytes to carry and deliver toxins. 195 33

We developed a model to assess the therapeutic effects of the 45-2D9-ricin A-chain immunotoxin (RTA) on pulmonary metastases. The 45-2D9 mouse monoclonal antibody recognizes a Mr 74,000 glycoprotein highly expressed by rat fibroblasts transformed with the Kirsten sarcoma virus (transformed rat fibroblasts). These cells metastasize spontaneously and form lung colonies in nu/nu and irradiated BALB/c mice. Injection i.v. of 45-2D9-RTA specifically reduced formation of spontaneous pulmonary metastases and lung colonies originating from freshly disaggregated tumor cells or cultured cells. Antibody alone or mixed with unconjugated ricin A chain and an immunotoxin that recognizes a melanoma-associated antigen were ineffective. Unconjugated 45-2D9 antibody specifically blocked the 45-2D9-RTA activity in vivo. Administration of the lysosomotrophic agents ammonium chloride and chloroquine in vivo did not potentiate immunotoxin-mediated reduction in lung colonies although they were effective in vitro. Monensin potentiated 45-2D9-RTA activity in vitro and in vivo.
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PMID:Mediation of reduction of spontaneous and experimental pulmonary metastases by ricin A-chain immunotoxin 45-2D9-RTA with potentiation by systemic monensin in mice. 325 69

We conducted a trial of a murine monoclonal antimelanoma antibody-ricin A chain immunotoxin (XOMAZYME-MEL) in 22 patients with metastatic malignant melanoma. The dose of immunotoxin administered ranged from 0.01 mg/kg daily for 5 days to 1 mg/kg daily for 4 days (total dose: 3.2 to 300 mg). Side effects observed in most patients were a transient fall in serum albumin with an associated fall in serum protein, weight gain, and fluid shifts resulting in edema. In addition, patients experienced mild to moderate malaise, fatigue, myalgia, decrease in appetite, and fevers. There was a transient decrease in voltage on electrocardiograms without clinical symptoms, change in serial echocardiograms or elevation of creatine phosphokinase MB isozyme levels. Symptoms consistent with mild allergic reactions were observed in three patients. The side effects were related to the dose of immunotoxin administered and were generally transient and reversible. Encouraging clinical results were observed, even after a single course of a low dose of immunotoxin. In addition, localization of antibody and A chain to sites of metastatic disease was demonstrated by immunoperoxidase staining of biopsy specimens. Additional studies are being conducted to continue the evaluation of safety and efficacy of immunotoxin therapy for malignancy.
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PMID:Therapy of patients with malignant melanoma using a monoclonal antimelanoma antibody-ricin A chain immunotoxin. 349 66

Regional chemotherapy to a tumour is most commonly delivered by intra-arterial infusion. An alternative method of regional drug delivery, isolated perfusion, may be used where anatomical considerations permit. The technique of isolated perfusion in the rabbit hindlimb is described. The use of this model with the implantable rabbit VX2 carcinoma allows estimation of drug uptake by normal tissues, primary tumour and popliteal lymph node metastases. Correlation of such data with blood flow measurements enables targeting of new cytotoxic agents to be evaluated. The effect of perfusate composition on tissue uptake of such an agent, the plant toxin ricin, has been determined.
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PMID:The rabbit as an experimental model for regional chemotherapy. 2. Isolated perfusion of hindlimbs. 377 42

From C57BL mouse melanoma B-16 cells, variant clones were selected in vitro which were resistant to the lectins wheat-germ agglutinin and ricin. Cells were also selected which survived toxic concentrations of concanavalin A. Four different in vivo assays using intradermal, intravenous, intraperitoneal and intramuscular injections were used to assess the tumorigenicity and metastasizing capacity of these lectin-resistant variants. It was concluded that to obtain a complete picture of the malignant properties of a given cell line or clone, all four assays have to be carried out. In comparison with the parental cells, the WGA-resistant cells showed a most dramatic decrease in metastasizing capacity through both lymphatic and vascular channels. Tumorigenicity was also reduced. The ricin-resistant cells showed a defective development into lung tumors and thus displayed a reduction in metastasis through the hematogenous route. Since this line did not change its capacity to metastasize via the lymphatic route, and the tumorigenicity was not significantly altered, it will be a good model for studies seeking to dissociate these two properties. The Con-A-selected cells, when injected intravenously, developed tumor nodules in the liver in addition to those in the lungs, while no striking alterations in tumorigenicity or metastasizing capacity could be detected in this line.
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PMID:Lectin-resistant variants of mouse melanoma cells. I. Altered metastasizing capacity and tumorigenicity. 708 30

To study the usefulness of an in vitro colony-forming assay in predicting individual clinical responses to chemotherapy, tumor cells obtained from 150 melanoma metastases (119 patients) were grown in soft agar according to the method of Courtenay and Mills (1978), and tested for sensitivity to DTIC, CCNU, vinblastine, procarbazine, abrin and ricin. In 83% of the cases colony formation was observed (plating efficiency, PE, greater than 0.01%). Twenty-seven per cent of the tumors gave PEs greater than 1%, 45% gave PEs in the range 0.1-0.9%, whereas 11% of the tumors gave 0.01-0.09%. The PEs were not correlated with the degree of pigmentation or with the clinical course. Evaluable chemosensitivity data were obtained on 104 metastases from 83 patients. Large differences in sensitivity were seen. In cases which were evaluable both in vivo and in vitro a clear correlation was found between the in vitro chemosensitivity, expressed as the expected growth delay, and the clinical response to chemotherapy. Tumors from patients with partial response, mixed response or stable disease after prior progression, all had rather high in vitro sensitivity to the drug used (expected growth delay greater than 2.0), whereas patients with progression had lower sensitivity. The results confirm that the soft agar method used here provides good culture conditions for human melanoma cells and show that chemosensitivity data can be obtained in a high percentage of melanoma patients. The approach used seems promising in aiding clinicians to adjust chemotherapy to individual patients.
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PMID:Colony growth and chemosensitivity in vitro of human melanoma biopsies. Relationship to clinical parameters. 709 99

Heterotypic adhesiveness of surface variant clones of B-16 melanoma cells exhibiting different metastasizing capacity was studied with respect to components of the vascular wall in culture including endothelial (E) and smooth muscle (SM) cells from adult bovine aorta, and the extracellular matrices laid down by them. The ricin-resistant cells (ricinR) and the wheat-germ agglutinin-resistant (WGAR) cells, both of which showed reduced hematogenous metastases in vivo, showed reduced adhesiveness specifically to endothelial cells and extracellular matrices. This reduced heterotypic adhesiveness is in contrast to the homotypic adhesive properties in which respect the ricinR cells had similar values to the parental cells, while the WGAR cells had much higher values than the latter. There appeared to be a positive correlation between metastasizing capacity and specific adhesiveness to E cells and the extracellular matrix surfaces.
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PMID:Altered adhesiveness of tumor cell surface variants with reduced metastasizing capacity--reduced adhesiveness to vascular wall components in culture. 716 Sep 43

A phase I/II study of the intralesional administration of ricin-labelled monoclonal antibodies was conducted in patients with hepatic metastases of gastrointestinal origin. The anti-carcinoembryonic antigen (CEA) antibody I-1 was conjugated to blocked ricin via a disulphide bridge. After a test dose of antibody, patients were injected with ricin-antibody conjugates under computed tomography (CT) guidance on two occasions 1 week apart. Patients with stable or responding disease would receive a third course. The dose of ricin relative to surface area was increased in a predefined manner in cohorts of 3 patients. A total of 27 patients with hepatic metastases were entered into this study. All patients had metastatic colorectal cancer (26 patients) or adenocarcinoma of unknown primary with elevated CEA levels (1 patient). The presence of malignancy was documented cytologically in 9 of 11 patients tested. Minor responses were seen in 7 patients. However, no major objective responses or changes in the growth rate of injected lesions were observed. Toxicity was generally mild, the most common being hepatic capsular pain 24-48 h after each injection. 6 patients experienced rigors. One patient had anaphylaxis. Human anti-mouse and anti-ricin antibody responses were observed. Although substantial amounts of ricin conjugated to monoclonal antibodies were delivered into single lesions, this therapeutic approach was unsuccessful. Future studies of ricin-labelled antibodies should incorporate the systemic administration of immunoconjugates.
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PMID:A phase I/II study of the intralesional injection of ricin-monoclonal antibody conjugates in patients with hepatic metastases. 799 4

Mitotoxins targeted via high-affinity growth factor receptors on the cell surface are a potential means of anticancer therapy. We have evaluated the effect of a chemically conjugated (FGF2-SAP) and a fusion protein (rFGF2-SAP) mitotoxin containing FGF-2 and saporin on normal (FHs 738B1) and malignant bladder cell lines (HT1197, TCCSUP, EJ-6, and RT4). The FGF-saporins demonstrated potent cytotoxicity in malignant bladder cell lines with an ID50 range of 0.13-13.6 nM, whereas cells derived from normal fetal bladder (FHs 738B1) were less sensitive to FGF2-saporins (ID50 > 100 nM). Greater than a 100-fold difference in cytotoxicity between FGF-saporins and unconjugated saporin was observed. Assessment of cellular FGF-2 content and secretion showed that FHs 738B1 and TCCSUP contained and secreted significantly more FGF-2 compared to other cell lines tested. (125)I-FGF-2 receptor binding studies showed the presence of high-affinity (pM) FGF receptors on all bladder cell lines. Cross-linking studies revealed the presence of a major receptor-ligand complex of 90 kDa on FHs 738B1 and 160-170 kDa on the other bladder cell lines. All cell lines studied, except RT4, expressed solely FGFR-1. These studies demonstrate that FGF2-saporins have antiproliferative activity on human bladder cancer cell lines. However, the number of high-affinity FGF receptors, and FGF-2 cellular content and secretion are not absolute determinants of cellular sensitivity to FGF2-saporins.
Clin Exp Metastasis 1997 Nov
PMID:Effect of fibroblast growth factor saporin mitotoxins on human bladder cell lines. 934 46


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