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

Cytokine-induced modulation of HLA expression on the cell surface of four human breast cancer cell lines was determined by continuous flow immunocytofluorometry with the aid of monoclonal antibodies directed to a non-polymorphic determinant of HLA class I and class II (DR) antigen. IFN-gamma and IFN-alpha were potent inducers of HLA class I in all examined cell lines, with decreasing inducibility as follows: BT-20, ZR-75-1, MCF-7 and MDA-MB-468 cells. HLA class II (DR) antigen was highly inducible by IFN-gamma in ZR-75-1 cells, followed by BT-20, MDA-MB-468 and MCF-7 cells. IFN-alpha increased the cell surface expression of DR antigen only in ZR-75-1 cells. IL-1-alpha induced a moderate level of HLA class I antigen in ZR-75-1, BT-20 and MDA-MB-468 cells, and HLA class II (DR) expression only in ZR-75-1 cells. This pattern of cell line inducibility by IL-1-alpha was similar to that induced by TNF-alpha. Differences in inducibility of HLA antigens on human breast cancer cell lines induced by different cytokines may reflect the differences in cytokine inducibility of the original tumor cells.
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PMID:Cytokine (IFN-alpha, IFN-gamma, IL-1-alpha, TNF-alpha)-induced modulation of HLA cell surface expression in human breast cancer cell lines. 143 41

Glucocorticoid steroids provide considerable protection against the systemic toxicity of tumor necrosis factor-alpha (TNF-alpha, cachexin). In animal experiments RU 38486 (mifepristone), a steroid antagonist, increased the synthesis of TNF and sensitized the animals to the cytotoxic action of TNF. As compared to the control and methylprednisolone-treated groups, mifepristone significantly increased the level of TNF in the serum, liver and spleen of lipopolysaccharide (LPS)-treated animals. In tissue cultures RU 38486 induced the TNF synthesis of myeloid cells and increased the TNF production of genetically modified HeLa cells, which synthesize TNF constitutively. Normal and tumor cell cultures exhibited increased sensitivity toward TNF in the presence of mifepristone.
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PMID:Effect of RU 38486 on TNF production and toxicity. 149 22

We have reported that diphtheria toxin (DTX) mediates target cell lysis and intranucleosomal DNA fragmentation (apoptosis) and also synergizes with TNF-alpha. In this paper, we examined which step in the pathway of DTX-mediated inhibition of protein synthesis was important for induction of cytolytic activity and for synergy. Using a DTX-sensitive tumor cell line, we first examined the activity of the mutant CRM 197, which does not catalyze the ADP ribosylation of elongation factor-2 (EF-2). CRM 197 was not cytolytic for target cells and did not mediate intranucleosomal DNA fragmentation of viable cells. The failure of CRM 197 to mediate target cell lysis suggested that the catalytic activity of DTX is prerequisite for target cell lysis. This was corroborated by demonstrating that MeSAdo, which blocks the biosynthesis of diphthamide, inhibited DTX-mediated protein synthesis inhibition and also blocked target cell lysis. Furthermore, the addition of nicotinamide, which competes with NAD+ on the DTX action site of EF-2, also blocked DTX-mediated lysis. These findings suggest that ADP-ribosylation of EF-2 may be a necessary step in the pathway leading to target cell lysis. In contrast to the sensitive line, the SKOV-3 tumor cell line is sensitive to protein synthesis inhibition by DTX but is not susceptible to cytolysis and apoptosis by DTX. Thus, protein synthesis inhibition by DTX is not sufficient to mediate target cell lysis. The synergy in cytotoxicity obtained with the combination of DTX and TNF-alpha was examined in order to determine the pathway mediated by DTX in synergy. Like the direct lysis by DTX, synergy was significantly reduced by MeSAdo and by nicotinamide. Furthermore, synergy was not observed with combination of CRM 197 and TNF-alpha. These results demonstrate that, in synergy, DTX may utilize the same pathway required for its cytolytic activity. Pseudomonas aeruginosa exotoxin shared most the properties shown for DTX. Altogether, these findings demonstrate that DTX-mediated apoptosis is initiated at a step beyond the ADP ribosylation of EF-2.
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PMID:Diphtheria toxin- and Pseudomonas A toxin-mediated apoptosis. ADP ribosylation of elongation factor-2 is required for DNA fragmentation and cell lysis and synergy with tumor necrosis factor-alpha. 151 72

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

To investigate a possible role of cytokines in parvovirus-mediated suppression of tumorigenesis, we tested in cell culture whether parvoviruses are able to induce interferon (IFN)-beta, tumor necrosis factor (TNF)-alpha or interleukin-6 (IL-6). Infection of rodent or human cells with the parvoviruses minute virus of mice (MVM), H-1 or adeno-associated virus (AAV) types 2 or 5 failed to induce expression of the luciferase or beta-galactosidase reporter genes transfected into these cells as constructs containing an IFN-beta promoter. Parvoviruses did weakly induce synthesis of TNF-alpha and of IL-6 in cell culture and could slightly enhance synthesis of these cytokines when induced by other agents. These in vitro data suggest that the rather unspecific tumor-suppressive properties of parvoviruses are unlikely to be attributable to stimulation of the synthesis of IFN, TNF or IL-6.
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PMID:Parvoviruses are inefficient in inducing interferon-beta, tumor necrosis factor-alpha, or interleukin-6 in mammalian cells. 152 25

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 tumor marker CA 19-9 was shown to be elevated in liver transplant patients, particularly during rejection. Serial serum samples taken from 24 patients after liver transplantation were examined for tumor markers CA 19-9, SLEX, CEA, and TNF-alpha. During rejection, 85% of the patients had elevated levels of CA 19-9. Patients with early rejection had persistently higher levels than patients without rejection. The serum levels were low in nonrejecting patients compared with those with rejection. Thus, the CA 19-9 marker cannot be considered a specific tumor marker. It may, however, be an indicator of an immune response or it may be a byproduct of an inflammatory reaction to a tumor or a transplant.
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PMID:Appearance of the tumor marker CA 19-9 in liver transplant patients during rejection episodes. 154 49

Apparently complex modulatory effects of alpha-interferon (alpha-IFN), tumor necrosis factor (TNF), and epidermal growth factor (EGF) have been found in neoplastic human thyroid cells, which could possibly affect the final outcome in neoplastic disease. This was achieved by examining the influence of alpha-IFN, TNF, and EGF alone and in combination, on human leukocyte antigen-DR (DR) antigen expression and viability of neoplastic and non-neoplastic human thyroid cells in culture. alpha-IFN-induced DR antigen expression on non-neoplastic human thyroid cells, whereas TNF-alpha or EGF alone were ineffective. The addition of the same TNF-alpha concentrations (10 to 100 ng/ml) to alpha-IFN enhanced the expression of DR antigens compared with the effect of alpha-IFN alone. However, EGF inhibited alpha-IFN-induced DR on the same cells and at the same concentrations (10 to 500 ng/ml) at which the growth factor alone was ineffective. In contrast to the common pattern of cytokine effects on DR expression of all nonmalignant thyroid cell lines, neoplastic thyroid cell lines showed divergent responses to alpha-IFN, TNF-alpha, and EGF. In three malignant thyroid cell lines that were DR negative (follicular carcinoma WRO 82-1 and NRO 87-1 cell lines, and anaplastic carcinoma ARO 81-1), DR antigen could be induced by alpha-IFN and enhanced by TNF-alpha, whereas EGF was ineffective. In a fourth cell line (an anaplastic carcinoma SW1736) alpha-IFN, TNF-alpha, and EGF alone were capable of inducing DR, and a combination of either TNF-alpha and EGF with alpha-IFN potentiated DR induction. In a fifth neoplastic cell line (papillary carcinoma, NPA) that constitutively expressed surface DR, its expression was inhibited by both alpha-IFN and TNF-alpha and was not affected by EGF.
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PMID:Divergent effects of cytokines on human leukocyte antigen-DR antigen expression of neoplastic and non-neoplastic human thyroid cells. 155 Oct 65

Both bacterial and mammalian heat shock proteins (HSP) are recognized by some T cells, and hsp60 recognition has been implicated in rheumatoid arthritis. We have developed a model to study the induction of hsp60 in human monocytic cell lines. An anti-mycobacterial hsp65 mAb (ML30), cross-reacting with human hsp60 was used to screen 21 human tumor cell lines in Western blot analysis. All T cell and B cell lymphomas constitutively expressed hsp60 protein at moderate to high levels, while little or no hsp60 protein was detected in two monocytic leukemia lines. Moderate to high levels of hsp60 mRNA and protein could be induced in the THP-I monocytic leukemia cell line by heat shock, retinoic acid, interferon (IFN)-gamma or tumor necrosis factor (TNF)-alpha treatment, the highest levels obtained with a combination of IFN-gamma/TNF-alpha. This was also seen using two rabbit anti-hsp60 antisera directed against the N-terminal or C-terminal part of the human hsp60 protein. The determinants detected by the ML30 mAb or the two rabbit anti-hsp60 antisera were not cell surface expressed, as measured with immunofluorescence (FACS) analysis on control cultured or cytokine treated cell lines. This could be a useful model for studies related to the induction of hsp60 in human cells.
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PMID:Induction of human hsp60 expression in monocytic cell lines. 156 88

Freedom from infection is the result of many tiers of immune defenses that harmoniously interact to rid the body of microorganisms and their products, which are perceived as foreign. The ability to distinguish self from nonself is embodied in lymphocytes, which serve both effector and regulatory functions. Through the elaboration of cytokines and immunoglobulins, lymphocytes recruit nonspecific immune effectors, focus their activity, and modulate the intensity of the immune response. The phylogenetically more primitive complement system serves a similar function. Although congenital defects in immune function occur, by far the most common causes of immunodeficiency are acquired and occur in patients treated for cancer with myelosuppressive, cytolytic drugs and in transplant recipients treated with immunosuppressants. HIV infection and malnutrition are responsible for even larger numbers of immunocompromised patients worldwide. The nature and severity of infections that occur as a result of immunodeficiency vary as a function of the immune effector targeted and the degree to which it is dysfunctional. Granulocytopenia is well tolerated unless the absolute number of circulating cells falls below 500/mm3. Profound granulocytopenia and deficits of neutrophil function are often manifest as bacterial or fungal infections. Complement deficiency predisposes to infection with encapsulated bacteria such as pneumococci, meningococci, and Haemophilus influenzae. T cells play such a central role in the immune response that their derangement is associated with susceptibility to almost any potential pathogen. These patients often succumb to mortal opportunistic infections. Recent advances in hybridoma and recombinant DNA technology have provided us with immunologic reagents that enable us to manipulate the immune response. Anti-CD3 monoclonal antibody has permitted salvage of solid organ transplants in well-defined clinical settings. Monoclonal antibodies against TNF-alpha and lipopolysaccharide may alter the consequences of gram-negative sepsis. Alternatively, recombinant cytokines have been associated with clinically significant tumor regression in selected patients, presumably by enhancing the nascent antitumor immune response. The development of immunologic reagents such as these in concert with our growing understanding of the immune system may translate to improved care for immunocompromised patients.
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PMID:Immune function and dysfunction. A primer for the radiologist. 157 Mar 93


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