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)

Interleukin-6 (IL-6) is a pleiotropic cytokine and has been shown to support the growth of T and B lymphocytes in the presence of mitogens in vitro. IL-6 can induce human natural killer (NK) and interleukin-2 (IL-2)-induced lymphokine-activated killer cell (LAK) activity in vitro. It can also mediate antitumor effects in various murine models. In order to understand the mechanism of in vivo action, we have investigated the proliferation of lymphoid cells in vivo and the effects on NK, and LAK cell activities in response to IL-6 administration in mice. In vivo proliferation was measured by labeling the DNA of dividing cells with [125I]iodo-2'-deoxyuridine. C57BL/6 mice were injected ip with either IL-6 or HBSS control two times a day for 3 days and in vivo proliferation was measured. For comparative purpose IL-2 was administered and in vivo effects were analyzed. IL-6 caused significant proliferation of cells mainly in the spleen, while, IL-2 caused proliferation in the lungs, liver, spleen, and kidneys. Pretreatment irradiation (500 rad) of mice abrogated the IL-6-induced proliferation indicating radiosensitive cells are involved. Furthermore, in vivo proliferation was not observed in young nude mice treated with IL-6. To investigate whether the proliferating cells were cytotoxic, we tested for LAK (vs. fresh MCA-102 tumor targets) and NK (vs. Yac-1 tumor targets) activities in the organs of mice treated with IL-6 or IL-2 by 4 h 51Cr-release assay. IL-2 administration induced the generation of LAK activity and increased NK cytotoxicity in various organs, but IL-6 had no effect.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Systemic administration of recombinant interleukin-6 in mice induces proliferation of lymphoid cells in vivo. 139 Dec 32

Alterations in cell-mediated cytotoxicity levels were studied in patients receiving recombinant interleukin-2 (rIL-2) via subcutaneous injection. Fourteen outpatients, aged 36-68 years, with progressive metastatic malignancies, were treated with weekly escalated doses of rIL-2, starting at 1.8 IU/m2/day for 6 days a week, up to 14.4 IU/m2/day during the 4th week of therapy. Patients presenting with stable disease thereafter were started on maintenance therapy and received 10.8 IU/m2 once weekly for up to 12 weeks. Patient mononuclear cells were isolated from fresh peripheral blood at various times throughout the treatment. Cells were assayed prior to and after further in vitro stimulation by rIL-2 (600 IU/ml for 7 days). Natural killing (NK) activity was measured by cytolysis of K 562 target cells, and lymphokine-activated killing (LAK) was determined by cytotoxicity against Daudi targets, respectively, in four effector:target ratios (E:T), using a standard 2-hour europium3+ release assay. Spontaneous NK cell function (E:T = 25:1) of freshly isolated peripheral blood mononuclear cells (PBMC) was enhanced significantly after 28 days of therapy (27.8 vs. 9.1% on day 0). LAK activity also markedly increased during therapy (26.2 vs. 5.4% on day 0). Further in vitro culture of these PBMC in the presence of rIL-2 resulted in day 28 non-MHC-restricted cytolytic activity of 63.2% (40.3% on day 0) against K 562 targets, and 64.9% (39.6% on day 0) against Daudi targets. Activation of cytolytic function by rIL-2 appeared to be dose-dependent, as measurable lytic capability decreased throughout maintenance therapy, while neither sex nor tumor entity prior to therapy or clinical response were correlated with cytotoxicity levels. Taken together, our observations demonstrate that stimulation of the non-MHC-restricted pathway of cytolytic activation, as measured by lysis of target cells, arises in patients treated with rIL-2 doses 5- to 30-fold lower than used previously in intravenous protocols, connecting effective clinical response rates with acceptable tolerability.
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PMID:In vivo and ex vivo antitumor activity in patients receiving low-dose subcutaneous recombinant interleukin-2. 139 1

To study parameters that affect the tumorigenicity of L1210 lymphoma we have analyzed the structure of MHC class I antigens of this tumor. In addition this tumor was transfected with interleukin-2 (IL-2) cDNA in order to determine the effects of high concentrations of IL-2 within the tumor environment. The nucleotide sequence of the class I Kd, Dd and Ld mRNAs from this tumor showed that the encoded amino acid sequence of the corresponding antigens is normal, thus suggesting that the tumorigenicity of L1210 lymphoma is not due to defective antigen presentation to tumor-specific cytotoxic T cells. In contrast, induction of IL-2 expression by cDNA transfection led to loss of tumorigenicity of the IL-2-secreting tumor cells. However, a fraction of long-term-surviving mice developed progressively growing variant tumors that showed substantial decrease or loss of IL-2 expression. These results suggest that IL-2 secretion by tumors is suicidal but, because of tumor heterogeneity, IL-2-loss-variant tumors may arise that are able to escape the immune defenses of the host. The observed consistent loss of IL-2 expression in variant tumors implies that specific targeting of large quantities of IL-2 to tumor cells may be a valuable approach to immunotherapy of cancer. In addition we find that under specific gamma ray irradiation IL-2-secreting tumor cells lose their ability to multiply yet continue to secrete IL-2 at levels equivalent to those secreted by unirradiated cells. Such IL-2-secreting irradiated tumor cells were found to be superior immunogens in comparison to the irradiated parental tumor cells, suggesting their use as tumor vaccines.
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PMID:Tumorigenicity of interleukin-2 (IL-2)-cDNA-transfected L1210 lymphoma and its in vivo variants is modulated by changes in IL-2 expression; potential therapeutic implications. 139 39

Specific immune responses against malignant brain tumors have been difficult to demonstrate. Moreover, immunotherapy has met with little success, despite using lymphocytes with high levels of cytotoxicity against brain tumor cells. Lymphokine-activated killer (LAK) cells that nonspecifically kill brain tumor cells are produced by stimulating resting precursors with high concentrations of interleukin-2 (IL-2). Cytotoxic T lymphocytes that specifically kill brain tumor cells are produced by stimulating antigen receptor-positive immune-cell precursors with tumor cells. In an attempt to gain insight into immune cell function against brain tumors, the present study compared the in vitro and in vivo activities of LAK cells and cytotoxic T lymphocytes produced against RT2, a fast-growing rat glioma cell line. Lymphokine-activated killer cells were produced by stimulating normal rat spleen cells with 1000 units of IL-2, and RT2-specific cytotoxic T lymphocytes were produced by priming them in vivo with RT2 and Corynebacterium parvum and restimulating primed spleen cells with RT2 in vitro. Lymphokine-activated killer cells were highly cytotoxic for a panel of syngeneic and allogeneic brain tumor and non-brain tumor target cells, including RT2, as measured in a 4-hour 51Cr release assay. Cytotoxic T lymphocytes were highly cytotoxic only for syngeneic brain tumor target cells. Lymphokine-activated killer cells and cytotoxic T lymphocytes were tested for in vivo antitumor activity against intracerebral RT2 by intravenous adoptive transfer of activated lymphocytes. Untreated rats died in approximately 2 weeks. Lymphokine-activated killer cells plus IL-2 failed to affect survival when treatment was initiated as early as 1 day following tumor inoculation. Cytotoxic T lymphocytes and IL-2 administered as late as Day 5 rejected progressing intracerebral tumor. Thus, although both cytotoxic T lymphocytes and LAK cells exhibited high levels of in vitro killing of glioma cells, only cytotoxic T lymphocytes rejected progressing intracerebral tumors.
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PMID:Antitumor activity against established intracerebral gliomas exhibited by cytotoxic T lymphocytes, but not by lymphokine-activated killer cells. 140 19

The proto-oncogene C-jun acts as a transcriptional activator or repressor for numerous cellular genes, and the overexpression of these genes may cause malignant transformation. JunB inhibits c-jun's transforming activities. We investigated the expression of jun genes in renal cell cancer (RCC) and their regulation by cytokines and transforming growth factor beta 1 (TGF-b1). The constitutive expression of c-jun was detected in 39 of 43 fresh frozen RCC, 5 of 10 normal kidneys, and the expression of junB detected in 28 of 34 RCC, 5 of 6 normal kidneys. C-jun was also found expressed in all 10 RCC tumor lines examined and junB was expressed at low levels in 6 of 10 renal tumor lines. TGF-b1 and tumor necrosis factor alpha (TNF-a) have been shown to alter the expression of jun genes in other tissue types. Additionally, TGF-b1, TNF-a, and gamma interferon (g-IFN) were shown to inhibit the growth of RCC. We found that TGF-b1 highly augmented the expression of junB (mean of 34 folds, p less than .05), but did not significantly alter the expression of c-jun, the transforming gene. In contrast, TNF-a significantly enhanced the expression of both c-jun (mean fold enhancement of 2.1, p less than .05) and junB (2.2 folds, p less than .05). Interleukin-2 (IL-2), interleukin-4 (IL-4) and g-IFN did not significantly alter jun expression. The findings presented suggest that c-jun may have a role in inducing malignant transformation in RCC and a novel mechanism by which TGF-b1 may exert its anti-tumor effects, via the activation of junB. Additionally, although TGF-b1, TNF-a, and g-IFN all have anti-proliferative actions on RCC in vitro, they were found to have different effects in altering jun expressions.
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PMID:The expression of C-jun and junB mRNA in renal cell cancer and in vitro regulation by transforming growth factor beta 1 and tumor necrosis factor alpha 1. 140 66

The treatment of metastatic renal cell carcinoma with immunotherapy has resulted in objective anti-tumor responses in 15-30% of patients. To enhance the therapeutic effects of immunotherapy, it is becoming evident that this approach should be combined with other treatment modalities. In this study, a spontaneously metastasizing murine renal adenocarcinoma (Renca), transplanted under the renal capsule, was treated with either radiation therapy, immunotherapy or a combination of both. In order to distinguish between the local and systemic effects of radiation therapy, total body irradiation was compared to irradiation of the tumor-bearing kidney only, or irradiation of the whole mouse with the tumor-bearing kidney shielded. Immunotherapy was administered with interleukin-2 (IL-2) alone or with IL-2 and lymphokine activated killer (LAK) cells. Combined radiation and immunotherapy induced a better anti-tumor response than either modality alone. The best response was obtained by local tumor irradiation and IL-2 therapy and resulted in a significant reduction in primary tumor size, elimination of lung metastases and a significant increase in survival.
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PMID:Synergy of radiation therapy and immunotherapy in murine renal cell carcinoma. 140 69

We have previously described an in vitro sensitization (IVS) procedure which enabled the generation of therapeutic T cells from tumor-bearing mice for adoptive immunotherapy. The procedure involved culture of tumor-draining lymph node (TDLN) cells with irradiated tumor in the presence of interleukin-2 (IL-2). The availability of many recombinant cytokines affords an opportunity to examine their effects on the immune response to tumor. In this study, we investigated the effect of tumor necrosis factor-alpha (TNF alpha) on the generation and function of IVS cells utilized in adoptive immunotherapy of the murine MCA 106 sarcoma. TNF alpha administered iv at nontherapeutic doses was found to enhance the antitumor efficacy mediated by IVS cells plus IL-2 in the treatment of pulmonary metastases. In contrast, TNF alpha administration to mice bearing progressive footpad tumors had inhibitory effects on the sensitization of tumor-reactive cells in TDLN since IVS cells generated from these animals displayed a diminished antitumor effect. This effect appeared to be due to a reduced number of tumor-reactive lymphoid cells in the TDLN since TNF alpha added to IVS cultures did not alter the antitumor efficacy of the resultant IVS effector cells. These findings indicate the divergent effects of TNF alpha on the immune response to tumor and adoptive immunotherapy with IVS cells.
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PMID:Divergent effects of TNF alpha in the adoptive immunotherapy of a murine sarcoma. 140 3

Limiting factors in systemic recombinant interleukin-2 (rIL2) therapy may be overcome by intratumoral (IT) administration. A series of experiments was conducted to assess the efficacy of IT rIL2 alone and in combination with LAK cells and IFN-gamma. C57BL/6 mice bearing B16-F10 subcutaneous tumors were randomly assigned to treatment groups including: noninjected controls, IT placebo (NaCl, D5W), IT bovine serum albumin (BSA), IT rIL2 (centrally and peripherally), IT rIL2/LAK, IT rIL2/IFN-gamma, and intraperitoneal (IP) rIL2. A tumor size-dependent dose of cytokine was injected daily and LAK cells were given weekly. Systemic immune response was assessed by splenocyte mitogenesis and T-cell subset distribution using thymidine radioassay and flow cytometry, respectively. In terms of survival and tumor growth rate, IT rIL2 was superior to noninjected control, IT placebo, IT BSA, and IP rIL2 (P less than 0.05). The addition of IT LAK cells conferred no therapeutic advantage. The combination of rIL2 and gamma IFN-gamma had a slight survival benefit over rIL2 alone (30.8 days vs 20.4 days). Histologic analysis demonstrated an increase presence of intratumoral macrophages in the IT rIL2-treated tumors (P less than 0.05). Lymphocyte mitogenesis and L3T4+ subset were not altered by any treatment. In vitro thymidine uptake by tumor cells was not affected by rIL2 nor IFN-gamma alone but the combination of rIL2 and IFN-gamma resulted in significant tumor cell growth inhibition. Spontaneous lung metastases were more prevalent following central IT rIL2 (75% vs 29%, P = 0.07) not accountable by needle trauma but avoidable by the use of peritumoral injection.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intratumoral rIL2-based immunotherapy in B16 melanoma. 140 10

The 4D1D4 hybridoma cells were derived from the fusion of spleen cells from BALB/c nude mice with NS-1 mouse myeloma cells. The surface phenotypes of 4D1D4 hybridoma cells were Thy-1.2+, L3T4 (CD4)-, Lyt-2 (CD8)-, Asialo GM1+ and p-55 interleukin-2 (IL-2) receptor (CD25)-. This phenotypic pattern was consistent with the surface phenotype of NK cells. The 4D1D4 cells showed the definite killer activity against a syngenic tumor cell line, RL male-1, but not against an allogenic YAC-1 line. The killer activity of the 4D1D4 cells was not affected by the addition of exogenous IL-2. It was, therefore, suggested that 4D1D4 cells might be representative of resting NK cells with expression of no functional IL-2 receptors. The hybridoma technology might be useful for establishment of the cloned NK cells.
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PMID:Establishment of hybridoma cells with natural killer(NK)-like activity against syngenic tumor cells. 140 67

Brain tumors are highly resistant to therapy. Their diffuse infiltrative nature and the relative inaccessibility of brain tissue to blood and lymph are barriers to surgical and cytotoxic treatments alike. The purpose of this study was to produce immune cells specifically reactive with an anaplastic rat glioma (RT2) and determine whether those cells could affect tumor progression in the brain. RT2-specific cytotoxic cells were prepared by priming rats in vivo with RT2 tumor cells and Corynebacterium parvum and stimulating the primed lymphocytes in vitro with irradiated RT2 tumor cells and interleukin-2 (IL-2). Cultured cells exhibited a high level of cytotoxicity against RT2, but not C6 (an allogeneic glioma), 3M2N (a syngeneic mammary tumor), or CSE (a syngeneic fibrosarcoma) tumor cells. To generate a model for therapy, rats were injected intracerebrally with RT2, generating progressing brain tumors, which killed untreated rats in approximately 2 weeks. To test the therapeutic potential of the effector cells, tumor-bearing rats were treated by intravenous injection of lymphocytes on Day 5 of tumor growth. Treated rats also received a 5-day course of systemic IL-2 beginning on Day 5. Treatment with IL-2 alone, RT2-primed spleen cells, or RT2-primed spleen cells stimulated in vitro with C6 did not affect rat survival. However, tumor-bearing rats treated with RT2-stimulated lymphocytes exhibited increased survival or were cured. Systemic IL-2 was an essential adjunct, because survival was not affected by treatment with effector cells alone. Therapy initiated on Day 8 of tumor progression lacked effect on survival.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Successful treatment of a malignant rat glioma with cytotoxic T lymphocytes. 140 33


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