Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to determine the in vivo immune response in glioblastoma, monoclonal and polyclonal antibodies specific for inflammatory leukocytes and immunoregulatory products were utilized to stain tissue from four surgical specimens. The more activated the inflammatory cells, the more activated the tumors appeared to be. In the tumor with the largest infiltration (Case 3), inflammatory cells were stained for interferon-gamma, interleukin-2, interleukin-1 beta, lymphotoxin, tumor necrosis factor-alpha, and transforming growth factor-beta. The tumor cells also expressed interleukin-1 beta, interleukin-6, transforming growth factor-beta, tumor necrosis factor-alpha, and prostaglandin E. In contrast, in the tumor with the least inflammatory response (Case 1), the tumor cells did not express any cytokines. Expression of cytokines by glioma cells was modest in the two cases with modest inflammatory responses. Cellular inflammation, primarily consisting of T cells and macrophages with few or no B cells or natural killer cells, was two- to 15-fold greater outside the tumor than within. In contrast to leukocytes outside the tumor, which were activated and expressing class II major histocompatibility antigens, leukocytes within the tumor parenchyma or at the tumor's edge were negative for these antigens. In the four specimens studied here, the tumor cells themselves were also negative for class II major histocompatibility antigens. These findings, although preliminary, suggest that inflammatory cells within gliomas are inactivated and that glioma cells may increase the expression of immunosuppressive cytokines in response to an increased lymphocyte infiltrate. This observation, if corroborated by more extensive studies, may help to explain the failure of immune treatments in glioblastoma multiforme.
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PMID:Inflammatory leukocytes associated with increased immunosuppression by glioblastoma. 131 61

Previously we have reported that human glial tumor cells secrete a factor(s) which suppresses the mitogen responsiveness of normal human peripheral blood lymphocytes (PBL) in a dose dependent manner. In this study we extend these observations and explore the possible mechanisms by which glioma-derived suppressor factor(s) (GSF) modulates lymphocyte reactivity. Preincubation of lymphocytes with GSF for 2 hrs induces suppression of lymphocyte mitogen responsiveness. GSF also inhibits production of interleukin-2 (IL-2) by mitogen activated human T-cells. Addition of delectinated or recombinant IL-2 to mitogen activated human T-cells in the presence of GSF does not restore the normal proliferative response of these cells. These findings suggest that GSF induces a defect in the expression of the receptor for IL-2 (IL-2R) on activated T-cells. Binding studies with radiolabeled IL-2 demonstrated that GSF suppresses and in some cases completely inhibits the expression of functional high affinity IL-2R on activated T-cells, thereby, preventing association of IL-2R with its receptor and the subsequent progression of the cell into the proliferative stage of the cell cycle. These cellular defects induced by GSF closely parallel the observed defects noted in T-cells obtained from patients with gliomas, indicating that the factors elicited from glial tumors may be responsible for the immunological deficits observed in patients with primary malignant intracranial tumors.
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PMID:Suppression of high affinity IL-2 receptors on mitogen activated lymphocytes by glioma-derived suppressor factor. 133 42

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

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

The use of adjuvant immunotherapy for the treatment of primary malignant brain tumors dates to studies performed in the 1960's and 1970's using non-specific immune stimulators. Although the theoretical designs have remained similar, recent advances in molecular biotechnology have produced a new group of recombinant cytokines, spawning a new generation of immunotherapy-based clinical trials. In contrast to other published Phase I/II studies, we have had highly encouraging preliminary results using lymphokine-activated killer (LAK) cells and recombinant human Interleukin-2 (rIL-2; Cetus, Emeryville, CA), when the patients' use of corticosteroids could be restricted while on study. Patients with recurrent grade 3/3 glioma received multiple cycles of autologous LAK cells and rIL-2, post-operatively, via an Ommaya reservoir implanted into the tumor cavity following re-operation. The overall median survival for 13 patients with grade 3/3 glioma has not yet been reached at 55 weeks following second surgery, [mean +/- SEM, 64.7 +/- 10.5 weeks], with 5 patients still alive. Three patients have had partial responses (PR) demonstrated by CT scanning. In addition, one patient with grade 2/3 glioma has had a complete response (CR), with the disappearance of all residual CT-documented enhancement and mass effect.
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PMID:The cellular immunotherapy of primary brain tumors. 144 66

The effects of glioma culture supernatant (GCS) and interleukin-2(IL-2) on the motility of autologous stimulated lymphocytes (ASL) were studied by using collagen gel system, chemotaxic chamber system and flow cytometric analysis. GCS inhibited the migration of ASL into collagen gel. It enhanced the ASL motility and the expression of CD 26 antigen on the cell surface. IL-2 inhibited the migration of ASL into collagen gel and had no influence on the motility of ASL, but enhanced the expression of CD 26 antigen. On the other hand, a clinical glioma specimen showed limited depth of ASL migration when injected into the tumor cavity in addition to the formation of fibrin like membrane on its surface and a layer of degenerated ASL under it. To make ASL therapy more effective to malignant glioma, the following measures should be recommended; 1) inject adequate volume of IL-2 into tumor cavity, 2) reduce the frequency of ASL administration, 3) wash out of glioma secreting factors, degenerated ASL and glioma cells in addition to reduce the volume of tumor tissue.
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PMID:[The motility of IL-2 activated lymphocytes into malignant glioma]. 147 10

The purpose of the present study was to define the usefulness of limiting dilution analysis (LDA) to enumerate glioma-reactive cytolytic T lymphocytes (CTL) as a constituent of tumor infiltrating lymphocytes (TIL) isolated from rat gliomas. Optimum LDA microculture conditions were defined by co-cultivating graded numbers of responder TIL together with 10(5) irradiated syngeneic rat splenocytes, 10(3) irradiated glioma cells, and 10 U/well of recombinant interleukin-2 incubated for 8 days. Antigenic specificity of the anti-tumor response was demonstrated by high levels of [3H]thymidine incorporation by TIL derived from F98 gliomas following stimulation with irradiated F98 glioma cells compared to low levels following stimulation with the antigenically distinct D74 glioma cells. Limiting dilution analysis showed that cytolytic T lymphocyte-precursors were present in TIL of F98 gliomas of immunized rats at an approximate frequency of 300 CTL/10(6) TIL, indicating that less than 1% of the TIL were tumor-reactive CTL. As determined by cell depletion experiments using various MoAbs and complement, the majority of the cytolytic activity detected against glioma targets was mediated by OX-8+ TIL. Split culture experiments revealed that high levels of glioma-reactive CTL activity and low levels of NK activity, which are simultaneously detected among TIL, were mediated by separate cell populations. Our data demonstrate that LDA microcultures can be used as a powerful tool to differentiate tumor-reactive CTL from other effector cell populations.
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PMID:Quantitation of glioma-reactive cytolytic T lymphocyte precursors by means of limiting dilution analysis. 153 41

Nine patients with a recurrent malignant glioma were treated with repeated intracavitary or intracerebroventricular injections of human recombinant interleukin-2 (rIL-2) alone or in combination with systemic interferon-alpha (IFN-alpha). Five patients received only rIL-2 and four were treated with rIL-2 plus subcutaneous injections of IFN-alpha. Therapy was administered on a Monday, Wednesday, Friday schedule for up to 10 weeks, beginning with a dose of 10,000 IU rIL-2/injection. Doses were escalated every two weeks until some toxicity was apparent. The maximum amount of rIL-2 any one patient in this group received was 580,000 IU. Patients on combination immunotherapy were held at an rIL-2 dosage of 10,000 IU while IFN-alpha, which began at 3 million IU, was escalated every other week up to 18 million IU/dose. They were then held at that IFN-alpha dosage and rIL-2 was increased to 50,000 IU. The total amount of rIL-2 and IFN-alpha any one in this group received was 510,000 IU and 417 million IU, respectively. Repeated injections of 10,000 IU rIL-2 were well-tolerated by all nine patients and no change in their functional status was seen. At doses at 50,000 IU rIL-2, increased edema around the tumor cavity was observed by MRI/CT scand in 3/5 patients and clinical side-effects in the form of somnolence and headache along with some morbidity specifically associated with tumor location were also seen. Patients receiving rIL-2+ IFN-alpha showed progressive fatigue, muscle weakness, and occasionally nausea. Two of these patients showed increased peritumoral edema on MRI/CT scan.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Treatment of recurrent malignant glioma by repeated intracerebral injections of human recombinant interleukin-2 alone or in combination with systemic interferon-alpha. Results of a phase I clinical trial. 154 81

The effect of immunotherapy with stimulated autologous lymphocytes (SAL) in malignant gliomas is documented and discussed in a bioptical and autoptical case study. A five-year-old child with a recurrently operated and radiated right hemispheric anaplastic astrocytoma died six weeks after immunotherapy with mitogen-activated killer cells and recombinant Interleukin-2. The autopsy revealed a large butterfly glioma with partially necrotic gelatinous tissue at the site of the SAL reservoir. The tumor cell density on the right was less than on the left hemisphere, and T-lymphocyte content was higher on the right hemisphere. These results demonstrate a local effect of SAL therapy in vivo, although the tumor progression as a whole could not be stopped. They also demonstrate the need of a detailed neuropathological examination in all cases of immunotherapy of malignant gliomas.
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PMID:Immunotherapy with stimulated autologous lymphocytes in a case of a juvenile anaplastic glioma. 164 Oct 79

It is well documented that drug delivery into experimental and human brain tumors is limited by the variably intact blood-brain barrier (BBB) at the growing edge. The aim of the present investigation was to examine the histopathological changes that occur after a single intralesional injection of human recombinant interleukin-2 (rIL-2) into a growing glioma and determine whether the injection improved delivery of cytotoxic drug into the neuropil surrounding the site of lymphokine injection. Because an intracerebral injection of rIL-2 causes a temporary breakdown in the BBB, we hoped to enhance drug penetration into peritumoral areas of brain with an intact BBB by using the novel biomodulating effect of rIL-2 on the cerebral endothelial cells. The results demonstrated that an intralesional injection of 7.2 x 10(4) National Units rIL-2 on Day 7 after tumor inoculation did not accentuate the already increased cerebrovascular permeability produced by the glioma nor did rIL-2 trigger additional or aggravate neurological deficits in glioma-bearing rats. Before the administration of chemotherapy in vivo, the RT-2 glioma cells were tested for in vitro sensitivity by colorimetric assay. At 24 hours after exposure to either methotrexate (MTX), vincristine (VIN), or doxorubicin (DOX), no significant inhibition of metabolic activity was observed. In contrast, a timed pulsed of any drug for 5 minutes caused significant dose-dependent inhibition of RT-2 glioma cells at 48 hours to 5 days after drug administration. Animal models receiving an intralesional injection of rIL-2 followed 3 days later by an intravenous dose of 30 mg/kg MTX, 0.23 mg/kg VIN, or 10 mg/kg DOX demonstrated that only MTX combined with intralesional rIL-2 significantly inhibited intracranial proliferation of RT-2 glioma cells. Use of intralesional rIL-2 and intravenous chemotherapy, however, did not significantly increase survival in this animal model of glioma. These results show that the combination of cytotoxic drugs with intralesional rIL-2 can be safely applied in the management of glioma and may form a rational basis for additional pharmacological investigations of a wider assortment of chemotherapies in combination with rIL-2 for intracranial malignancies.
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PMID:Cerebrovascular effects and tumor kinetics after a single intratumoral injection of human recombinant interleukin-2 alone or in combination with intravenous chemotherapy in a rat model of glioma. 164 Nov 14


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