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)

The expression of membrane-associated forms of lymphotoxin (LT) and TNF were examined on cell lines of T, B, and myeloid origin, IL-2 dependent T cell clones, and peripheral blood lymphocytes. Inducible and constitutive patterns of surface LT expression were found on T cells as exemplified by the II-23.D7, a CD4+T cell hybridoma, and HUT-78, a T cell lymphoma. Phorbol ester induced surface LT expression on Ramos, an EBV transformed B cell line, but at a slower rate of appearance when compared to the II-23.D7. Secretion of LT was rapidly inducible by phorbol ester in II-23.D7 and also in HUT-78 but with slower kinetics; surface LT expression continued in both lines after secretion had ceased. Low levels of membrane TNF were transiently induced on II-23.D7 and HUT-78, but none was observed on Ramos. Peripheral blood monocytes and some myeloid tumor lines did not express surface LT. Several T cell clones expressed surface LT after Ag-specific stimulation, and expression persisted several days. Stimulation through the TCR or by IL-2 rapidly induced surface LT on resting peripheral T cells and CD56+ NK cells; pokeweed mitogen activation induced expression on CD20+ B cells. Consistent with previous results, immunoprecipitation with anti-LT mAb showed that LT was complexed with a distinct 33 kDa glycoprotein (p33) on cells that expressed surface LT, whereas secreted LT was not associated with p33. Surface and secreted modes of LT expression by activated T, B, and NK cells suggests that LT can be utilized as either a localized or diffusible mediator in immune responses.
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PMID:Expression of surface lymphotoxin and tumor necrosis factor on activated T, B, and natural killer cells. 128 Nov 93

We previously reported a dramatically increased number of macrophages in tumor-bearing mice. In this study, we investigated the involvement of CSF in that phenomenon. CSF-1 responding cells as macrophages precursors increased significantly in number in the spleens of tumor-bearing mice as compared with those in normal mice. Splenic cells and sera from the tumor-bearing mice respectively expressed CSF-1 in mRNA and serum protein levels, but failed to express the other CSF (granulocyte-macrophage-CSF or IL-3). Nonadherent splenic mononuclear cells (< 0.5% macrophages) from normal mice proliferated and differentiated into mature macrophages in culture within 7 days with recombinant mouse CSF-1 (rCSF-1). Both macrophages harvested from tumor-bearing mice and those activated in vitro with rCSF-1 expressed mostly Mac-1, -2 (and -3) Ag, showed yeast phagocytosis, produced IL-1 but not IL-2 or IL-3, and displayed potent cytotoxicity against NK cell resistant Meth-A tumor cells. These macrophages also expressed lipocortin I mRNA and secreted lipocortin I protein, and suppressed mitogenic responses of splenic lymphocytes. rCSF-1-activated macrophages derived from nonadherent splenic cells expressed both CSF-1 and CSF-1 receptor (c-fms) mRNA. Administration of rCSF-1 into normal mice induced hemopoietic and immunologic alternations similar to those observed in tumor-bearing mice. These results suggest that CSF-1 is involved in the dramatic increase of macrophages in tumor-bearing mice, possibly through an autocrine or paracrine loop.
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PMID:Role of colony-stimulating factor-1 in macrophage activation in tumor-bearing mice. 128 Nov 98

Murine tumor cells engineered to express IL-2 have been shown to be rejected by the syngeneic host, which is then protected against a subsequent tumorigenic challenge. To assess whether IL-2 has to be produced by the tumor cells themselves, or whether its local delivery would be sufficient to promote such beneficial effects, the syngeneic tumor cells were co-inoculated with allogeneic or xenogeneic cells secreting IL-2, selected after gene transfection. In several murine systems, it was observed that this is an efficient approach for controlling the growth of the syngeneic tumor. However, animals which rejected the tumor were not protected against a subsequent challenge. Several lines of evidence indicate that NK cells play a major role in tumor rejection induced by the IL-2 expressing histoincompatible vector cells. Thus, while local delivery of IL-2 in the vicinity of a tumor might not be sufficient to promote a systemic long-term specific antitumor immune response, it can control the growth of the primary syngeneic tumor. These experiments demonstrate the feasibility of using genetically engineered histoincompatible cells (which are rejected by the host's immune system) as a transient delivery system in vivo.
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PMID:Inhibition of tumor growth by histoincompatible cells expressing interleukin-2. 128 66

We have investigated the cellular requirements for IL-2 production by autocrine proliferating tumor cells from four patients with adult T cell leukemia (ATL). Cultures of these ATL cells both produced endogenous IL-2 protein in the absence of added mitogen and proliferated at higher levels when exogenous recombinant IL-2 was added. Depletion of macrophages in the tumor cell cultures resulted in a sharp decline in tumor cell IL-2 production, while re-addition of macrophages reconstituted this response. Macrophage-derived factors including IL-6 and IL-1 also reconstituted IL-2 production in these macrophage depleted cultures. These results raise the possibility that macrophages may play a central role in HTLV-I mediated immortalization of T cells.
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PMID:Interleukin-2 production by primary adult T cell leukemia tumor cells is macrophage dependent. 128 88

On the basis of our previous preliminary data which showed that the pineal hormone melatonin (MLT) may potentiate IL-2 activity and reduce the dose of IL-2 required to determine an effective host antitumor response, we performed a clinical study with low-dose IL-2 given once/day subcutaneously (3 million IU/day for 6 days/week for 4 weeks) in association with MLT (50 mg/day orally at 8.00 p.m. every day) as a second-line therapy in metastatic colorectal cancer patients pretreated with 5-fluorouracil. Evaluable patients were 13/14, and most of them showed disseminated liver metastases. No objective tumor regression was seen. A stabilization of disease was achieved in 4/13 patients (median duration 5+ months), and the other 9 patients progressed. Mean number of lymphocytes and eosinophils significantly increased during the treatment. Moreover, the mean increase in lymphocyte number was significantly higher in patients with stable disease than in those with progressive disease, whereas there was no difference as regards eosinophils. Serum levels of neopterin and tumor necrosis factor (TNF) significantly increased during therapy, and TNF increase was correlated to the side effects rather than to the control of cancer development. This study shows that neuroimmunotherapy with low-dose interleukin-2 and MLT, even though capable of determining an evident expansion of immune cells involved in host antitumor response, does not seem to be effective in terms of tumor regression in metastatic colon cancer patients pretreated with 5-fluorouracil.
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PMID:Neuroimmunotherapy with subcutaneous low-dose interleukin-2 and the pineal hormone melatonin as a second-line treatment in metastatic colorectal carcinoma. 129 33

Twenty-four patients with histologically proven metastatic malignant melanoma were included in a phase II trial of recombinant IL-2 (rIL-2, RU 49637). Twenty million international units (IU)/m2/day were given by continuous intravenous infusion on days 1 to 5, 15 to 18, and 29 to 31, and then monthly for 5 days until disease progression or major intolerance developed. All patients were evaluable for response and toxicity. Toxicity was consistent with one case of myocardial ischemia, 13 cases of grade III and IV hypotension, and 15 cases of proven sepsis. There were 8 objective responses: 4 of them were of short duration as they were observed on day 31 only. An activation of the immune system was detected in all patients. It was demonstrated by an increase in lymphocyte populations, especially in activated NK cells. A tendency for higher numbers of cytotoxic cells was found in patients with objective tumor responses. These results indicate a role for rIL-2 RU 49637 in treating patients with metastatic malignant melanoma. However, further trials are required to determine its optimal dosage and schedule of administration.
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PMID:IL-2 phase II trial in metastatic melanoma: analysis of clinical and immunological parameters. 130 93

A 35-year-old woman was admitted to our hospital with a 3 month history of progressive paraparesis and impairment of bowel and bladder function. MRI suggested a malignant glioma at the level of T9 to L1. Laminectomy and subtotal removal of the tumor was performed. The surgical specimen was a glioblastoma multiforme. An aggressive adjuvant therapy was scheduled to prevent rapid local regrowth and leptomeningeal dissemination. Radiotherapy with a total dose of 65Gy was delivered with chemotherapy including ACNU (2mg/kg) and vincristine (0.2mg/kg). Lymphokine-activated killer (LAK) cells were given intrathecally with a total dose of 1.6 x 10(9) LAK cells with 3 x 10(4) units of IL-2. MRI taken 6 months after surgery revealed no residual tumor, and no malignant cell was detected in the patient's CSF. After physiotherapy, she became able to walk with a stick and was discharged. Chemotherapy (ACNU 2mg/kg/8 weeks) had been further continued for 2 years. She did well until 14 months after surgery, when paraparesis recurred and rapidly progressed to completism. MRI revealed a spinal cord swelling with marked edema, suggesting delayed radiation necrosis. Two years after surgery, MRI showed a marked atrophy of the spinal cord, and no residual tumor. But 3 years after surgery, a round tumor at the level of T11 and T12 was revealed on MRI, and she was admitted to our hospital again. A spinal cord amputation was performed, and the tumor was totally removed without worsening her neurological symptoms. Surgical specimen of the tumor was glioblastoma multiforme again.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[A case of spinal cord glioblastoma multiforme]. 131 Aug 3

Cytokines can have both negative and positive effects on cells undergoing carcinogenesis. The promotion and progression phases of carcinogenesis may be affected by autocrine loops involving cytokines with growth factor activities such as IL-1, IL-2, low molecular weight B cell growth factor, TNF, IL-3, GM-CSF, M-CSF and IL-9. Aberrations in cytokine receptors such as the truncated EGF receptor present in v-erB promotes the growth of neoplastic cells. Aberrant signaling mechanisms, as found with spleen focus-forming virus, which mimics the ligand that activates the erythropoietin receptor, can also contribute to proliferation of preneoplastic and neoplastic cells. In contrast, cytokines such as interferons, LIF, TGF-beta, TNF and leukoregulin, with antiproliferative or differentiating activities, are sometimes capable of inhibiting carcinogenesis. Transfection of tumor cells with cytokine genes, such as IL-2, IL-4 and TNF, can cause suppression of in vivo tumor cell growth by mobilizing host immune and inflammatory cell responses. Thus cytokines and their receptors may play a direct role in early stages of tumor cell development and growth.
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PMID:Cytokines as positive and negative regulators of tumor promotion and progression. 132 42

Autocrine production of growth factors is thought to be an essential element in the development of hemopoietic tumors in vivo. Tumor-derived cell lines frequently show this capability in vitro. It is not understood how autonomous growth in vitro is maintained by lymphoid cell lines that are not of tumorigenic origin. We have previously established human B cell clones that proliferate in serum-free media with unlimited potential. However, the cells need a critical density for continuous growth. Culture supernatant conditioned by these cell lines sustained proliferation even in low density cultures. All B cell clones analyzed were found to secrete the cytokines IL-1 alpha, IL-6, TNF-alpha, and TNF-beta whereas no activity of IL-2, IL-4, low m. w.-B cell growth factor, CSF, or IFN-gamma was recorded. In low density cultures supplemented with rIL-1 alpha, +/- IL-6, +/- TNF-alpha, and +/- TNF-beta together, B cell proliferation is maintained to the same extent as with conditioned medium. Addition of anti-sense oligonucleotides directed to the mRNA of IL-1 alpha, IL-6, and TNF-alpha, respectively, resulted in growth arrest and cell death. This effect could be prevented by supplementation with these cytokines. Scatchard plot analyses and internalization studies revealed that the cells express on their surface high affinity receptors for IL-1 alpha, IL-6, and TNF, respectively, and internalize the cytokines from the supernatant. These results demonstrate that (i) autonomous growth of immortalized B cells is maintained by secretion and reinternalization of IL-1 alpha, IL-6, TNF-alpha, and TNF-beta, (ii) these cytokines act in a synergistic fashion, and (iii) autocrine growth stimulation of human B cells in vitro does not necessarily represent their tumorigenic potential in vivo.
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PMID:Four cell-secreted cytokines act synergistically to maintain long term proliferation of human B cell lines in vitro. 132 86

The production of IL-1 and IL-6 by pituitary cells has recently been demonstrated. In this study we investigated the expression of IL-2 and its receptor (IL-2R) by pituitary cells of different species. In Northern blots, a single hybridizing band of 1 kb, identical to that in normal stimulated lymphocytes, was obtained with specific IL-2 probes. In the mouse AT-20 pituitary tumor cell line, IL-2 mRNA expression was detected after stimulation with corticotropin-releasing hormone or phorbol myristate acetate. In human corticotrophic adenoma cells, basal IL-2 mRNA expression as well as IL-2 secretion were further stimulated by phorbol myristate acetate. Both adenoma and AtT-20 cells showed detectable amounts of IL-2R mRNA and by immunofluorescence, IL-2R membrane expression. In addition, dual immunofluorescence studies in rat anterior pituitary cells demonstrated colocalization of IL-2R with ACTH-positive cells and other cell types expressing the receptor. In addition to the action of lymphocyte-produced IL-2, this cytokine may have a paracrine or autocrine regulatory role within the pituitary. It remains to be established whether IL-2 production occurs in the normal pituitary or is intrinsic to the process of tumor development of these cells. IL-2 may be involved in the growth control of pituitary cells.
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PMID:Interleukin-2 and interleukin-2 receptor expression in human corticotrophic adenoma and murine pituitary cell cultures. 133 Nov 77


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