Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Enzyme characteristics of in vitro activated peritoneal macrophages of normal and BP6-TU2 tumor-bearing rats were compared with those of nonactivated macrophages. The activating effect of LPS, IFN-gamma, IL-2, TPA, TNF and Zymosan was assessed by the determination of the activities of alpha-naphthyl butyrate esterase (ANBE), tartrate-resistant acid phosphatase (TRAP), beta glucuronidase (BG) and 5'nucleotidase (5'NT). The used individual activators induced the macrophage enzyme activities in different degrees. LPS, TPA and TNF appeared to be the most effective activators of enzyme activities in macrophages of normal rats. IFN-gamma, IL-2 and Zymosan were less effective. The macrophages of BP6-TU2 tumor-bearing rats were less sensitive to the stimulatory effect of activators with respect to their enzyme activation capacity, except for TRAP activity. The results indicate that enzyme ANBE is an adequate marker of rat peritoneal macrophages. Enzyme TRAP determines the macrophage activation degree more expressively, in comparison with BG and 5'NT. The differences in enzyme activities could be a suitable marker of macrophage activation and might suggest the dependence on the pathway of macrophage stimulation by distinct activators.
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PMID:Cytochemical study of activated peritoneal macrophages in normal and tumor-bearing rats. 143 43

We previously reported that human macrophages cultured with IL-2 for a long period (lymphokine-activated macrophages, LAMs) showed high tumoricidal activity against human and murine leukemic cell lines through a different mechanism from lymphokine-activated killer (LAK) cells. In this report, we investigated the effects of various cytokines on the tumoricidal activity of IL-2-induced LAMs against HeLa cells. CSF-1 and IL-1 were found to enhance the tumoricidal activity of LAM in a dose-dependent manner, whereas IFN-gamma and TNF had inhibitory effects. CSF-1 in combination with a low dose of IL-2 synergistically induced LAMs with highly tumoricidal activity. We also found that monocytes from some donors that did not respond to IL-2 were differentiated to tumoricidal macrophages by treatment with a combination of CSF-1 and IL-2. Furthermore, IL-2-induced LAMs were found to produce cytotoxic factors in the culture medium when they were cocultured with tumor cells, and the cytotoxic activity in the culture supernatant of LAMs was also increased by the incubation of LAMs with CSF-1. The cytotoxicity of the supernatants from macrophages with different tumoricidal activity correlated with their cell-mediated cytotoxicity. It is suggested from these results that the cytotoxicity of LAMs is regulated by CSF-1, IL-1, IFN-gamma, and TNF, and that the production of cytotoxic molecules is involved in cell-mediated killing by LAMs.
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PMID:Activation of human monocytes by interleukin-2 and various cytokines. 150 58

We have investigated the tumor-specific reactivity of different T-cell subsets from mice primed with clonal variants of L5178Y and P815 cells treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). In both tumor systems, anti-parental tumor immunity and protection against non-immunogenic clones were only induced by vaccinating the hosts with highly immunogenic cell variants, and the effect correlated with the detection of TATA-specific delayed-type hypersensitivity (DTH) reactions. The footpad reaction was transferable with spleen cell populations from immunized mice, and enrichment of splenic lymphocytes in L3T4+ but not Lyt-2+ lymphocytes increased the footpad swelling. Unfractionated spleen cell populations from immunized mice released high amounts of IL-2 and IFN-gamma in vitro in response to parental antigens. Purified L3T4+ and Lyt-2+ lymphocytes also produced IFN-gamma when incubated in vitro with the parental tumors and accessory cells. It is suggested that the mechanisms of anti-parental tumor immunity induced by MNNG-treated variants may be similar to those described previously for triazene-xenogenized L5178Y/DTIC cells, and may involve induction of a tumor-specific DTH reaction and IFN-gamma-mediated stimulation of non-specific tumoricidal effects.
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PMID:Tumor-specific L3T4+ and Lyt-2+ lymphocytes in mice primed to mutagenized cell variants. 151 82

Inflammatory mouse peritoneal macrophages were activated by IFN-gamma in synergy with IL-2 or Lipid A to mediate TNF production for autocrine generation of cytotoxic nitric oxide (NO) to kill P815 or L1210 tumor targets. It was determined that for IL-2, but not Lipid A, to effectively trigger activation of IFN-gamma-primed macrophages, the tumor targets must be also present for interaction with effector macrophages to mediate the production of TNF and NO. IFN-gamma- and IL-2-activated macrophages from syngeneic DBA/2 and allogeneic C3H mice had identical MHC-unrestricted requirements for interaction with DBA/2 mouse-derived P815 and L1210 targets to mediate production of TNF and NO for tumor cytotoxicity. To further define the mechanistic requirements for macrophage-tumor target interaction, IFN-gamma- and IL-2-activated macrophages were separated from P815 targets in culture by a semipermeable membrane. Under these conditions, both TNF and NO were produced by the macrophage, which indicated that the requirement for tumor target-macrophage interaction may be due to a soluble factor produced by the target rather than to direct physical contact. This was confirmed by experiments in which 24-h cell-free culture fluids, derived from either P815 or L1210 tumor targets, substituted for the intact tumor cells in the stimulation of TNF mRNA synthesis and secretion with NO generation of TNF mRNA synthesis and secretion with NO generation by IFN-gamma- and IL-2-activated C3H or DBA/2 macrophages. The activity in 24-h culture fluids derived from P815 and L1210 tumor targets was tentatively designated as tumor-derived recognition factor(s) (TDRF) since it was produced constitutively by the tumor targets and synergized with IFN-gamma and IL-2 to induce macrophage production of TNF and NO for death of the same targets. A variety of nontransformed human and mouse fibroblasts, mouse spleen lymphocytes, and two adherent mouse fibrosarcomas did not produce detectable TDRF activity, whereas two mouse T lymphomas, EL4 and EL4.IL-2, produced TDRF activity similar to L1210 mouse leukemia and P815 mastocytoma. The C3H/MCA, a TDRF-nonproducing mouse fibrosarcoma, was susceptible to cytotoxicity mediated by macrophages activated by IFN-gamma and Lipid A, but not by IL-2 triggering. Exogenous TDRF derived from L1210 targets reconstituted the cytotoxic activity for C3H/MCA MCA targets mediated by IFN-gamma- and IL-2-activated macrophages accompanied by the production of TNF and cytotoxic NO.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Tumor target-derived soluble factor synergizes with IFN-gamma and IL-2 to activate macrophages for tumor necrosis factor and nitric oxide production to mediate cytotoxicity of the same target. 151 76

The present studies were designed to assess the ability of primary cultures of bone marrow cells to produce nitric oxide. We found that two inflammatory stimuli, IFN-gamma and LPS, were potent inducers of nitric oxide production by bone marrow cells. In addition, the CSF granulocyte-macrophage (GM)-CSF and IL-3 as well as TNF-alpha, while inactive by themselves, were synergistic with LPS and IFN-gamma in inducing nitric oxide production. Maximal effects were observed with combinations of GM-CSF and LPS. Nitric oxide production by bone marrow cells was found to be dependent on the presence of L-arginine in the culture medium and inhibitable by NG-monomethyl-L-arginine and L-canavanine, two nitric oxide synthase inhibitors. Nitric oxide produced by the cells was also suppressed by TGF-beta 1 and the tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate. Separation of bone marrow cells by density gradient centrifugation and flow cytometry revealed that the granulocyte-containing fraction was largely responsible for nitric oxide production. In additional experiments we found that treatment of bone marrow cells with GM-CSF significantly stimulated bone marrow cell growth. In contrast, the combination of GM-CSF and LPS or IFN-gamma markedly suppressed cellular proliferation. This suppression was completely reversed by treatment of the cells with NG-monomethyl-L-arginine. Taken together, these data demonstrate that various inflammatory stimuli and cytokines induce nitric oxide production by primary cultures of bone marrow cells and that this mediator may play a role in the regulation of bone marrow cell growth and development.
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PMID:Production of nitric oxide by murine bone marrow cells. Inverse correlation with cellular proliferation. 151 78

Peritumoral injection of human IL-2-activated natural killer cells into nude mice consistently induced regression of xenografts of human squamous cell carcinoma of the head and neck (SCCHN). To determine the mechanisms responsible for the tumor regression, the lymphoid cells infiltrating the tumor stroma at 24 to 48 h after adoptive immunotherapy were examined by in situ hybridization for the presence of mRNA for cytokines or IL-2R. Numerous lymphoid cells expressing cytokine or IL-2R genes were observed in these tumors, whereas the cultured IL-2-activated NK cells used for therapy were negative. Thus, it appeared that the transferred NK cells became activated in situ after coming into proximity with the tumor cells. To analyze this phenomenon, fresh or cultured human NK cells were coincubated in vitro with irradiated human SCCHN cell line, PCI-1, with or without the presence of IL-2. Expression of mRNA for IL-2R, perforin, and various cytokines was observed within 5 h. Contact with the tumor cells stimulated NK cells to proliferate, secrete IFN-gamma, TNF-alpha, and soluble IL-2R, up-regulate cell surface expression of IL2R p55 and p75 as well as CD16 Ag, and mediate higher levels of antitumor activity in 51Cr-release assays. In addition, supernatants of in vitro-activated NK cells significantly inhibited proliferation of SCCHN cell lines. By examining the effects of neutralizing mAb to various cytokines, this inhibitory activity was shown to be partially attributable to IFN-gamma. To determine the possible in vivo role of soluble factors produced by activated human NK cells, the supernatants (0.2 ml) or rIFN-gamma (10(5) U) were injected perilesionally each day for 2 wk into 3-day SCCHN established in immunosuppressed nude mice. These treatments caused significant (p less than 0.02) inhibition of tumor growth. The results of our studies indicate that human NK cells are strongly activated by SCCHN cells and that the consequent release of cytokines contribute to the regression of SCCHN growing in nude mice.
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PMID:Role of cytokines in the adoptive immunotherapy of an experimental model of human head and neck cancer by human IL-2-activated natural killer cells. 153 88

The observation that malignant cells express antigens that may be recognized by immunocytes and that immune effector mechanisms have the capability of destroying tumor cells has increased our appreciation of the biology of cancer and its relationship to immune function as well as offered new options for therapeutic intervention. Clinical trials are in progress to evaluate several different approaches to modifying the host's immune response against tumor. One approach is to administer agents that have direct activity against the malignancy. For example, antibody conjugates bring cytotoxic molecules of chemotherapy, radioisotopes, or toxins directly to the tumor. A second approach is to administer agents that modulate the host's own antitumor response such as IFN-alpha and IFN-gamma. Adoptive cellular immunotherapy aimed at isolating and expanding the host's own tumor-specific lymphocytes and inducing activation and proliferation with lymphokines such as IL-2 has shown encouraging results. Even though clinical data are still quite premature, it is reasonable to assume that in the future immunomodulation including the stimulation of immune effector mechanisms to eradicate tumor, the reconstitution of immune deficiency in diseases such as AIDS, the suppression of immune function to avoid graft rejection and GVHD, and the isolation and insertion of genes encoding tumor antigens into recombinant vectors to immunize the host to the tumor antigen will be commonly and successfully employed.
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PMID:The role of the immune system in the pathogenesis of cancer. 154 19

Polyethylene glycolated (pegylated) interleukin-2 (PEG IL-2) was administered as a weekly i.v. bolus to patients with metastatic cancer in a phase-I trial. Efficacy, toxicity and pharmacokinetics have been described previously. To explore mechanism of IL-2 action and discover predictors of efficacy, the levels of several lymphokines were measured in pharmacokinetic serum samples. IL-1 beta and IL-6 were elevated in many patients before PEG IL-2 administration, forming a continuous, log-normal distribution among patients. The levels of the two lymphokines were strongly correlated. However, no significant correlation could be found between these levels, clinical chemistry, or tumor regression seen after PEG IL-2 administration. Three hours after PEG IL-2 administration, IL-1 beta and IL-6 levels, if elevated, fell to normal. In all patients, independent of initial levels, IL-6 and IFN-gamma, but not IL-1 beta, increased 4 to 6 h after the injection and then fell rapidly, even though PEG IL-2 levels were high and often changed only slightly during this period. This suggests an active shut down of lymphokine synthesis, or an increase in elimination rate. After the fourth administration of PEG IL-2, the peak level of IFN-gamma was 2 to 20 times higher than after the first, while the peak level of IL-6 did not change in a consistent direction. Responding patients had typical peak levels of IL-6 and IFN-gamma. Low levels of TNF and IL-4 were occasionally seen before and after PEG IL-2 administration, but no consistent pattern was evident.
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PMID:Suppression and transient induction of lymphokines in cancer patients after administration of polyethylene glycolated interleukin-2. 154 19

Quantitative evaluation of the levels of endogenous gamma-interferon (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) in the extracts of tumor, peritumoral and normal colorectal tissues resected surgically from 43 patients with colorectal adenocarcinoma was carried out using solid-phase, sandwich radioimmunoassay (RIA). The levels of both IFN-gamma and TNF-alpha detected in the tumor tissues were higher than those in the peritumoral and normal tissues obtained from each patient. A significant negative correlation was observed between the levels of IFN-gamma and TNF-alpha in each tumor tissue. The decrease of endogenous IFN-gamma in the tumors correlated with the advance of histopathological stages. Thirty seven patients were classified into three types according to the endogenous IFN-gamma distribution (intratumoral dominant type, peritumoral dominant type and nonreactive type). There was no significant difference concerning to the tumor diameters among them. However, the mean stage of the intratumoral dominant type was significantly earlier than that of the nonreactive types. On the other hand, the increase of endogenous TNF-alpha correlated with the maximum diameter of primary tumors. The production of endogenous TNF-alpha was localized in the tumor tissues, and the significant elevation of endogenous TNF-alpha was not observed in the peritumoral tissues. The immunohistochemical staining of IFN-gamma- and TNF-alpha-producing cells in tumor tissues represented that IFN-gamma was mainly produced by CD4+CD8-CD11c- lymphocytes and that TNF-alpha was mainly produced by CD4-CD8-CD11c+ cells with macrophage-like morphology. These results suggest that CD4+ lymphocytes producing IFN-gamma might play an important role in the anti-tumor response against cancer progression in human colorectal adenocarcinoma.
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PMID:[Detection of endogenous IFN-gamma and TNF-alpha in tumor-infiltrating mononuclear cells of human colorectal cancer]. 155 60

Eight patients with epithelial ovarian carcinoma persisting after chemotherapy, selected for having a residual tumor no larger than 1 cm in diameter, were treated intra-peritoneally (i.p.) with recombinant interferon-gamma twice weekly for 3 months. Toxicity consisted of fever and malaise in all patients and a transient rise in hepatic enzyme levels in 3 patients. The cytotoxic function of peripheral blood and peritoneal tumor-associated lymphocytes (TAL) and macrophages (TAM), was studied using cell lines as targets. I.p. IFN-gamma augmented the cytotoxic activity of lymphocytes and mononuclear phagocytes: stimulation was more marked and more frequently observed with TAL and occasionally TAM than with blood effectors, suggesting preferential modulation at the site of tumor growth and IFN administration. Surgical laparotomy revealed that 1 patient had a complete response, 2 a partial response and 2 had stable disease, while 3 patients had progressive disease. In this small series of patients there was no obvious, strict correlation between immunomodulation by IFN-gamma and clinical response. These results indicate that, in contrast to its lack of activity in advanced ovarian carcinoma, IFN-gamma has definite immunomodulatory and antitumor activity in the presence of limited tumor burden.
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PMID:Anti-tumor and immunomodulatory activity of intraperitoneal IFN-gamma in ovarian carcinoma patients with minimal residual tumor after chemotherapy. 156 43


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