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)

We have engineered highly aggressive murine mammary tumor cell line 410.4 to express interleukin-10 (IL-10) and compared the behavior in vivo of these cells to parental 410.4 and 410.4 transfected with the control plasmid (410.4-neo). Transplantation of parental 410.4 and 410.4-neo tumor cells to syngeneic mice resulted in progressive growth and death from pulmonary metastases. In contrast, both subcutaneous growth and metastatic disease were completely inhibited by IL-10 expression. We had shown previously that the antimetastatic activity of IL-10 is expressed in T-cell-deficient mice but is lost when NK activity is suppressed. This study confirms that IL-10 is dependent on NK activity, since no therapeutic effect is seen in C.B-17/IcrCrl-SCID/Beige mice which lack T, B, and NK cell function. We compared the sensitivity to NK lysis of four IL-10-expressing clones with 410.4 and 410.4-neo and found that IL-10 expression resulted in enhanced NK lysis of all four clones. Furthermore, IL-10 expression was correlated with decreased surface expression of MHC class I Kd, Ld, and Dd. Pretreatment of IL-10-expressing cell lines with IFN-gamma reversed the class I downregulation and reduced the sensitivity of these cells to NK lysis. Taken together, these studies in vitro and in vivo are consistent with a mechanism by which IL-10 expression downregulates class I expression, leading to enhanced NK lysis of tumor cells, resulting in control of metastatic disease.
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PMID:Interleukin-10 inhibits tumor metastasis, downregulates MHC class I, and enhances NK lysis. 931 39

Effects on the liver of the antiangiogenesis agent O-(chloroacetyl-carbamoyl) fumagillol (TNP-470) on hematogenous metastasis of a human pancreatic carcinoma cell line were examined. One million PCI-43 cells, a human pancreas carcinoma cell line, were injected into the spleen of SCID beige mice, then TNP-470 at 30 mg/kg was administered subcutaneously every other day. The mice were killed 6 or 10 weeks thereafter and metastatic nodules in the liver were counted and measured microscopically. Metastases were inhibited and an approximately 10% loss of weight was evident in the TNP-470-administered mice. There was no suppression in maximal size of metastatic colonies in mice given the agent for 6 weeks, while inhibition was apparent in mice given the drug for 10 weeks. Suppression of proliferation and an increase in apoptosis were evident in metastatic nodules in the TNP-470-administered groups, following stainings for proliferative cell nuclear antigen and terminal deoxytransferase-mediated dUTP-biotin nick end-labeling, respectively. TNP-470 inhibited the proliferation of human umbilical vein endothelial cells but not PCI-43 in vitro. TNP-470 did not suppress production of vascular endothelial growth factor by PCI-43 cells. Neovascularization in vivo induced by PCI-43 cells was suppressed in the TNP-470-administered mice, using a diffusion chamber placed in subcutaneous tissues of SCID beige mice. These observations suggest that inhibition of angiogenesis is effective in suppressing establishment and subsequent growth of hematogenous micrometastases of pancreatic adenocarcinoma to the liver.
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PMID:Inhibitory effects of the antiangiogenic agent TNP-470 on establishment and growth of hematogenous metastasis of human pancreatic carcinoma in SCID beige mice in vivo. 933 88

A recombinant humanized antibody-interleukin 2 fusion protein (huKS1/4-IL-2) was used to direct IL-2 to the tumor microenvironment and elicit a T cell-mediated eradication of established pulmonary and hepatic CT26-KSA colon carcinoma metastases in syngeneic BALB/c mice. This antitumor effect was specific because a fusion protein, which was nonreactive with these tumor cells, failed to exert any such effect. The efficacy of the huKS1/4-IL-2 fusion protein in eliminating metastases was documented because mixtures of monoclonal antibody huKS1/4 with recombinant human IL-2 were ineffective and, at best, only partially reduced tumor load. Two lines of evidence indicated the eradication of metastases and the absence of minimal residual disease in animals treated with the fusion protein: first, the lack of detection of CT26-KSA cells by reverse transcription-PCR, which can detect one tumor cell in 10(6) liver cells; and second, the tripling of life span. The effector mechanism involved in this tumor eradication is dependent on T cells because the IL-2-directed therapy is ineffective in T cell-deficient SCID mice. The essential effector cells were further characterized as CD8+ T cells by in vivo depletion studies. Such T cells, isolated from tumor-bearing mice after fusion protein therapy, elicited MHC class I-restricted cytotoxicity in vitro against colon carcinoma target cells. Taken together, these data indicate that fusion protein-directed IL-2 therapy induces a T cell-dependent host immune response capable of eradicating established colon cancer metastases in an animal tumor model.
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PMID:Elimination of established murine colon carcinoma metastases by antibody-interleukin 2 fusion protein therapy. 935 62

Production of interleukin-6 (IL-6) by human pancreatic carcinoma cells inversely correlates with potentials for blood-borne metastasis to the liver in nude mice. IL-6 cDNA was transfected to PCI-43, one of our cultured pancreatic carcinoma cell lines that does not produce IL-6 and generates numerous metastases to the liver. An IL-6 high-producer clone (PCI-43h) generated few metastases; IL-6 production thus has a direct effect on metastasis, whereas other transfectants (PCI-43l and PCI-43n), which are IL-6 low-, and IL-6 non-producers, respectively, did generate metastases. Tumor-reactive IgG, which mediated antibody-dependent cellular cytotoxicity (ADCC) in vitro, was detected in sera from recipient nude mice inoculated with PCI-43h but not in sera from mice given PCI-43l, PCI-43n or parent PCI-43. Tumor-reactive IgM was detected in sera from all mice, irrespective of inoculated PCI-43 species, with a slight augmentation being noted in PCI-43h-inoculated nude mice. Severe combined immunodeficiency (SCID) beige mice were then used as recipients for PCI-43 species, and tumorigeneity was examined by s.c. inoculation of a suboptimal number of PCI-43 transfectants (1 x 10(6)/0.1 ml). Only PCI-43h formed palpable masses in SCID beige mice, whereas it first grew to be palpable but subsequently became not palpable in nude mice, thereby revealing a dual action of tumor-derived IL-6. Thus, tumor-derived IL-6 confers growth promotion in SCID beige mice, while the same cytokine exhibits anti-tumorigenic functions, presumably through humoral immune responses, in nude mice.
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PMID:Interleukin-6 produced by pancreatic carcinoma cells enhances humoral immune responses against tumor cells: a possible event in tumor regression. 946 20

Tumor establishment and metastasis are dependent on extracellular matrix proteolysis, tumor cell migration, and angiogenesis. Urokinase plasminogen activator (uPA) and its receptor are essential mediators of these processes. The purpose of this study was to investigate the effect of a recombinant human uPAR antagonist on growth, establishment, and metastasis of tumors derived from human cancer cell lines. A noncatalytic recombinant protein, consisting of amino acids 1-137 of human uPA and the CH2 and CH3 regions of mouse IgG1 (uPA-IgG), was expressed, purified, and shown to bind specifically to human uPAR and to saturate the surface of human tumor cells which express uPAR. Daily i.p. administration of uPA-IgG to nude mice extended latencies of unstaged tumors derived from Lox melanoma and SW48 colon carcinoma cells by 7.7 and 5.5 days, respectively. uPA-IgG treatment did not affect the growth of Lox or KB tumors staged to 200 mg before antagonist treatment commenced. The effect of uPA-IgG on the establishment of micrometastases was assessed in SCID mice. KB head/neck tumor cells were injected in the tail vein and allowed to seed for 48 h before initiation of daily i.p. injections of uPA-IgG for 24 days. The number of lung colonies ranged between 5 and 30% of vehicle-treated mice in two separate experiments. Furthermore, a single 800 microg dose of uPA-IgG administered 1 h prior to tail vein injection of KB cells reduced lung colony formation to just 3.5% of vehicle-treated SCID mice. These data demonstrate that antagonism of uPAR arrested metastasis and inhibited the establishment of primary tumors and micrometastases. Thus, small molecule uPAR antagonists may serve as useful adjuvant agents in combination with existing cancer chemotherapy.
Clin Exp Metastasis 1998 Jan
PMID:Inhibition of establishment of primary and micrometastatic tumors by a urokinase plasminogen activator receptor antagonist. 950 73

Bi-specific antibody fragments (bAB) are used in tumour therapy as a means to redirect and to strengthen effector cell function. It would be of great therapeutic advantage if, in addition, recruitment, expansion and the state of activity of effector cells are influenced by targeting through a bAB. This question was explored in the melanoma-bearing SCID mouse. The chemically coupled Fab' fragments of an anti-CD3 and an anti-p97 monoclonal antibody (MAB) were characterized in vitro for dual binding specificity and support of lymphokine-activated-killer-cell (LAKC) cytotoxicity towards a highly aggressive human melanoma line, which was significantly increased and exceeded levels of antibody-dependent cellular cytotoxicity observed in the presence of the anti-p97 MAB. The in vivo efficacy was tested in the SCID mouse: 5, 10 and 15 days after i.p. application of tumour cells, mice received LAKC (2 x 10(7)) together with bAB (150-100 microg). The application of bAB was repeated at days 20 and 25. Application of LAKC to melanoma-bearing SCID mice prolonged the mean survival time from 22 days of the untreated control group to 41 days. Anti-p97 did not exert any additive effect. In the presence of bAB, melanoma cells did not grow in 3 out of 8 mice. The mean survival time of the 5 mice developing tumours was 45 days. Importantly, none of the mice receiving bAB developed metastases, which were seen in 100% of animals receiving tumour cells or tumour cells plus LAKC or tumour cells plus LAKC plus anti-p97. As revealed by LAKC recovered from the SCID mice, the efficacy of the bAB was based on prolonged persistence of CD8-positive cells as well as on expansion and activation of CD4-positive cells, which was observed only in bAB-treated tumour-bearing mice. The efficiency in recruiting cytotoxic and, in particular, helper T cells suggests bAB as a valuable additive in immunotherapeutic treatment of melanoma patients.
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PMID:In vivo activation and expansion of T cells by a bi-specific antibody abolishes metastasis formation of human melanoma cells in SCID mice. 950 37

Malignant pleural effusion (PE) is a frequent problem in lung cancer. In this study, we established a model of malignant PE of human adenocarcinoma cells, PC-14, in SCID mice. Intravenously injected PC-14 cells formed colonies in the lungs as early as week 4 after tumor inoculation, and produced bloody PE in all recipient SCID mice by week 8. Pretreatment of SCID mice with anti-mouse IL-2 receptor beta chain antibody (TM-beta 1) to deplete natural killer (NK) cells markedly promoted the production of bloody PE and metastases to multiple organs, such as the lungs, liver, kidneys, and lymph nodes 4 weeks after tumor inoculation. Histological studies indicated that PC-14 cells formed colonies in the lungs, and then invaded the pleura and spread to the pleural cavity. To establish cell lines with a high potential to produce PE, we harvested PE, expanded the tumor cells in vitro, and injected them into SCID mice again. By four in vivo selection cycles in this way we obtained PC-14-PM4 cells, which produce lung metastases and PE earlier than PC-14 cells. The survival of SCID mice inoculated with PC-14-PM4 cells was significantly shorter than that of mice inoculated with PC-14 cells. The expressions of adhesion molecules, such as CD44, CD49d, ICAM-1, and MHC class I, on PC-14-PM4 cells tended to increase compared with PC-14 cells. These changes of adhesion molecules seem to be one of possible mechanisms involved in higher metastatic potential of PC-14-PM4 cells. PE models with PC-14 and PC-14-PM4 cells should be useful for biological and preclinical studies on malignant PE produced by human lung cancer.
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PMID:Model of malignant pleural effusion of human lung adenocarcinoma in SCID mice. 956 4

Recent work has shown that chemically modified tetracyclines (CMTs) are potent inhibitors of matrix metalloproteinase (MMP) activity, both in vitro and in vivo, which is distinct from their antimicrobial activities (Golub et al. Crit Rev Oral Biol Med, 2, 297-321, 1991; Ryan et al. Curr Opin Rheumatol, 8, 23847, 1996). The process of tumor cell invasion requires MMP-mediated degradation of extracellular matrix barriers as a key step in the metastasic cascade. In this study, we examined the effect(s) of doxycycline and CMTs on extracellular levels of gelatinase A and B activity from a highly invasive and metastatic human melanoma cell line C8161, and correlated these observations with changes in the cells' biological behavior in an in vitro invasion assay and in an in vivo SCID mouse model. The results indicate that coincident with the ability of these compounds to differentially suppress extracellular levels of gelatinase activity, C8161 cells treated with doxycycline, CMT-1, CMT-3, or CMT-6 were less invasive in vitro in a dose-dependent manner (3-50 microg/ml). Furthermore, data derived from the in vivo model indicate that SCID mice dosed orally with CMT-1 or CMT-3 contained a reduced number of lung metastases following i.v. injection of C8161 cells via tail vein inoculation. These observations suggest that careful screening of different CMTs could lead to the identification of compounds which suppress the formation and magnitude of metastases associated with certain cancers, and if used as an adjunct to other treatment regimes, lead to greater efficacy in the treatment of metastatic cancers.
Clin Exp Metastasis 1998 Apr
PMID:Chemically modified tetracyclines inhibit human melanoma cell invasion and metastasis. 956 39

IL-12 is a potent immunoregulatory cytokine that has been shown to mediate tumor regression in a variety of tumor models. We describe the construction of AdCMV-IL-12, a recombinant adenovirus that encodes both subunits of IL-12 under transcriptional control of the CMV promoter. This recombinant virus efficiently infects a wide variety of cell types leading to the production of high levels of biologically active IL-12. Because the liver is a primary site of infection after i.v.-administered adenovirus, we tested the therapeutic efficacy of this virus in a murine hepatic metastasis tumor model. Systemic administration of AdCMV-IL-12 dramatically inhibited the formation of 3-day Renca hepatic metastases (mean of 16 metastases per liver) compared with the control virus AdCMV-betagal (mean of 209) or vehicle alone (mean of 272). Histologic analysis indicated that metastatic growth inhibition was accompanied by a dramatic perivascular infiltrate consisting of T cells, macrophages, and neutrophils. Therapeutic efficacy was not diminished in animals depleted of CD4+ or CD8+ T cells, or in SCID mice, even after NK cell ablation. In the latter case, a hepatic perivascular infiltrate composed of macrophages and neutrophils was observed after AdCMV-IL-12-treatment, while numerous activated Kupffer cells were noted in the hepatic parenchyma. Analysis of therapy-induced changes in hepatic gene expression demonstrated increased levels of IP-10 and Mig RNAs, but no increase in iNOS, Fas, or FasL RNA levels was observed. Our data suggest a model of metastatic growth inhibition mediated by nonlymphocyte effector cells including macrophages and neutrophils and that may involve anti-angiogenic chemokines.
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PMID:T cell- and NK cell-independent inhibition of hepatic metastases by systemic administration of an IL-12-expressing recombinant adenovirus. 960 49

We evaluated the in vivo anti-metastatic activity of recombinant Ancylostoma caninum Anticoagulant Peptide (rAcAP), a potent (Ki = 265 pM) and specific active site inhibitor of human coagulation factor Xa originally isolated from bloodfeeding hookworms. Subcutaneous injection of SCID mice with rAcAP (0.01-0.2 mg/mouse) prior to tail vein injection of LOX human melanoma cells resulted in a dose dependent reduction in pulmonary metastases. In order to elucidate potential mechanisms of rAcAP's anti-metastatic activity, experiments were carried out to identify specific interactions between factor Xa and LOX. Binding of biotinylated factor Xa to LOX monolayers was both specific and saturable (Kd = 15 nM). Competition experiments using antibodies to previously identified factor Xa binding proteins, including factor V/Va, effector cell protease receptor-1, and tissue factor pathway inhibitor failed to implicate any of these molecules as significant binding sites for Factor Xa. Functional prothrombinase activity was also supported by LOX, with a half maximal rate of thrombin generation detected at a factor Xa concentration of 2.4 nM. Additional competition experiments using an excess of either rAcAP or active site blocked factor Xa (EGR-Xa) revealed that most of the total factor Xa binding to LOX is mediated via interaction with the enzyme's active site, predicting that the vast majority of cell-associated factor Xa does not participate directly in thrombin generation. In addition to establishing two distinct mechanisms of factor Xa binding to melanoma, these data raise the possibility that rAcAP's antimetastatic effect in vivo might involve novel non-coagulant pathways, perhaps via inhibition of active-site mediated interactions between factor Xa and tumor cells.
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PMID:Ancylostoma caninum anticoagulant peptide blocks metastasis in vivo and inhibits factor Xa binding to melanoma cells in vitro. 960 44


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