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

Prostaglandin (PG) D2 was examined for its effect on the growth of a mouse brain tumor cell line in vitro and in vivo. In this study, we used 203 glioma which had been originally induced by methylcholanthrene in C57BL mice and proved to be subcutaneously transplantable and also maintainable in a cell culture system in vitro. Marked inhibition of cell growth was observed in a PGD2-treated group in vitro at a concentration of 5 micrograms/ml. In the in vivo experiment, intraperitoneal or intratumoral administration of PGD2 (0.5 mg/kg) every day for four weeks was started after subcutaneous transplantation. In a control group, the same amount of ethanol without PGD2 was administered. Inhibition of tumor growth was seen with intratumoral administration, although no inhibition was seen with intraperitoneal administration. Histological examination revealed no remarkable change after PGD2 administration. However, on the DNA histogram, an increment of the G0G1 phase and a decrement of the G2M phase occurred after intratumoral administration of PGD2. It was suggested that local administration of PGD2 might be effective through the inhibition of DNA synthesis.
 ...
PMID:[Effect of prostaglandin D2 on the growth of mouse glioma]. 345 95

Case histories of 5 tumor patients treated with natural leukocyte interferon-alpha (IFN-alpha) are presented. One patient with juvenile laryngeal papillomatosis responded well to interferon treatment, but the disease recurred when therapy was withdrawn. Upon reinstitution of treatment, the patient once again responded well. Another patient with myelomatosis also responded well to interferon therapy and in this case, too, the tumor recurred when interferon treatment was withdrawn. Reinstitution of interferon therapy was, however, unsuccessful. One patient with generalized giant cell tumor of bone responded with regression after more than 5 years of interferon treatment. Another patient with pulmonary osteosarcoma metastases, having received irradiation and interferon combination therapy followed by sole interferon treatment, responded well with a lasting stationary radiogram after 6 years of interferon treatment. One patient with malignant glioma, showing signs of tumor growth during the first few months of interferon therapy, eventually responded, and became disease-free after 6 years. The latter 3 patients are continuously receiving interferon therapy although more than 5 years have elapsed since their interferon therapy was initiated. It is suggested that interferon therapy for malignant tumors be given for life (or to progression of disease) in responding patients. Such a concept entails biological implications for interferon therapy in general and for antitumor action of interferons in particular. Other possible clinical schedules should only be constructed within the framework of controlled clinical trials.
 ...
PMID:Does successful interferon treatment of tumor patients require life-long treatment? 347 1

The C6 spheroid implantation glioma model is a simple, easily reproduced model for primary gliomas in which C6 astrocytoma cells are grown in vitro as spheroids and subsequently implanted into the brains of Sprague Dawley rat hosts. This report describes the growth, histology, vessel architecture and vascular permeability of the resulting tumors. The appearance of the tumor was investigated by light and electron microscopy, and by using the alkaline phosphatase technique. The leakage of tracer was measured from vessels in the tumor and peritumoral area at various times during tumor development. The spheroid implant produces a fully vascularized, rapidly growing tumor with many of the characteristics of glioblastoma multiforme, from an avascular focus of neoplastic cells. The major advantage of this model is that the tumors grow in a spheroidal fashion and the tumor-brain interface can be easily located. Many of the important events in the process of vascularization take place at the tumor-brain interface. Two distinctive vascular events appear to occur simultaneously: proliferation of blood vessels and their growth into the tumor mass so that they develop into typical, permeable tumor vessels, and migration of tumor cells along normal vessels into the surrounding brain. Tumor vessels were permeable to the tracer Evans Blue (EB) from the earliest days of ingrowth. Leakage of the EB increased as the tumors increased in size, but eventually leakage plateaued as tumors developed necrotic centers. It is well known that the structural and permeability characteristics of vessels associated with the tumor affect tumor growth. This model will be useful for a number of proposed studies including assessment of various clinical therapies on tumor growth and development, and more specifically, quantitative analysis of the vascularization process in tumors.
 ...
PMID:A new glioma model in rat: the C6 spheroid implantation technique permeability and vascular characterization. 357 71

After radiotherapy, 20 patients, 18 with documented progression of malignant glioma and 2 with Grade II astrocytoma, received a total of 52 courses of intracarotid 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) at a dose of 150 mg/m2 dissolved in 5% dextrose in water. The patients were treated at 6-week intervals for a maximum of five courses of chemotherapy per patient. Response to treatment was analyzed on computed tomographic scans by measuring the volume of the enhancing tumor and any central low density. From these data, tumor doubling times ranging from 110 to 968 days were obtained. An 11 to 60% reduction in enhancing tumor volume was noted in 8 patients, 2 of whom had a greater than 50% decrease in tumor volume. One patient had no change in tumor volume 110 weeks after the initiation of BCNU chemotherapy. Four patients had tumor in more than one vascular territory; tumor growth was arrested in the perfused territory, but continued in the nonperfused area. In 1 of the 4 patients, tumor also grew along a shunt catheter tract and spread over the surface of the ipsilateral hemisphere. One patient developed clinically asymptomatic leukoencephalopathy after five courses of BCNU. Two patients had postradiation leukoencephalopathy before BCNU treatment. Seventeen patients had peritumoral low density with mass effect after BCNU; thus, the true incidence of BCNU-related leukoencephalopathy could not be determined. All patients experienced transient unilateral orbital pain during the infusion and scleral erythema that lasted for several hours afterward. Loss of vision was noted in 2 patients, although it seemed to be related to the therapy in only 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Intracarotid chemotherapy with 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) in 5% dextrose in water in the treatment of malignant glioma. 358 50

A crucial manifestation of malignant gliomas is the regrowth of already-invaded neoplastic cells after surgical intervention. One possible approach for inhibiting such tumor growth is to utilize the tumoricidal potential of macrophages. In order to investigate the clinical application of this concept, peritoneal exudate cells (PEC) activated in vitro and in vivo by immunomodulating agents were tested for cytotoxic activity against murine glioma (203-glioma) cells. As immunomodulating agents, heat-killed Propionibacterium acnes (P. acnes), OK-432 and Concanavilin A supernatant (Con A sup) were used in these experiments. P. acnes was provided by Kowa Pharmaceutical Co., Tokyo, and OK-432 by Chugai Pharmaceutical Co., Ltd., Tokyo. Klinische Einheit (KE) units were used to express the strength of the preparation, with 1 KE equal to 0.1 mg of dried streptococci. Con A sup was produced by Con A pulsing of BALB/c splenocytes resuspended in complete medium. PEC harvested from mice to which 5% glycogen in saline had been inoculated intraperitoneally 6 d previously were activated in vitro by P. acnes (P. acnes-PEC), OK-432 (OK-432-PEC) and Con A sup (Con A-PEC). The cytotoxic activities of P. acnes-PEC, OK-432-PEC and Con A-PEC were approximately 25%, 65% and 60%, respectively. PEC were then collected from mice into which either 100 micrograms of P. acnes or 1 KE of OK-432 had been injected intraperitoneally several times. The antitumor effects of P. acnes-PEC and OK-432-PEC were about 35% and 50%, respectively. These activated PEC demonstrated cytotoxic activity against murine glioma in the tumor neutralization assay (Winn assay). Also, the antitumor efficacy of OK-432-PEC belonged mainly to adherent cells. Meningeal gliomatosis (MG) models were prepared for clinical studies. Viable 203-glioma cells (5 X 10(6) were injected percutaneously into the cisterna magna of C57BL/6 mice. The median survival time (MST) of the untreated group was 8.5 days. The MST of the groups treated by intraperitoneal and intracisternal administration of P. acnes were 26 and 33 days. This therapy significantly prolonged the survival time of these models, particularly by the intracisternal treatment. The differential cell count by Giemsa staining and latexphagocytic cell findings revealed that macrophages accounted for more than 90% of the P. acnes-PEC. These results may indicate that activated (PEC) macrophages were induced intracisternally by P. acnes and that activated macrophages induced intraperitoneally exerted antitumor effects in MG models.
 ...
PMID:[Antitumor efficacy of activated macrophages against murine glioma cells]. 371 55

The subcapsular renal transplantation tumor model was explored to standardize the growth of rat RN6 neurinoma and RG2 glioma nitrosourea-induced clonal cell lines in syngeneic and allogeneic systems. Growth of RN6 and RG2 tumor spheroids was compared with that of solid subcutaneous tumor pieces transplanted under the renal capsule. Two morphometrical methods were applied to evaluate growth rates. Tumor specimens were examined histologically with regard to their morphology, extent of immune reactions, and development of tumor necroses. The take rate was 98%. In the syngeneic system linear progressive tumor growth was found, while in preirradiated allogeneic rats this was only the case up to 21 to 25 days post transplantation (p.t.). Strong rejection reactions in the allogeneic RN6 tumors were noted from 4 to 7 days p.t. resulting in total tumor rejection after 10 to 14 days. Both kinds of tumors, especially in the first days of growth, were characterized by strong desmoplastic reaction with rich reticulin fiber formation. However, after 10 days, in the center of RG2 subcapsular renal tumors (SRT) this kind of reaction was found only in the vicinity of tumor vessels, while RN6 SRT demonstrated reticulin fibers around tumor cells in all cases studied. The transplantation experiments revealed that the malignant RN6 and RG2 spheroids represent a suitable tool to study three-dimensional early tumor growth in both in vivo and in vitro cultures. The model of spheroid transplantation under the renal capsule is simple to handle and well reproducible. Compared with subcutaneous tumors the SRT model has advantages in early stages of tumor growth because the tumors are clearly visible grossly and can be easily submitted to adequate morphometry, indicating that this model may be suitable for experimental chemotherapy and radiotherapy studies.
 ...
PMID:Subcapsular renal transplantation of neurogenic tumors and tumor spheroids. A comparative study of RN6 and RG2 tumor clones after syngeneic and allogeneic transplantation. 373 66

The authors conducted experiments to study the efficacy of active specific immunotherapy and immunoprophylaxis with tumor cell lysate obtained by means of metabolites of Bac. mesentericus AB-56 in inoculated malignant glioma of the brain. Active immunotherapy was found to produce the best effect in the early latent period of tumor growth. It was less effective when tumor cells were inoculated in large doses and when the treatment was applied late. The investigated method of tumor cell inactivation was not used previously in neuro-oncology.
 ...
PMID:[Efficacy of experimental active specific immunotherapy and immunoprevention of malignant gliomas of the brain]. 373 92

Experimental models of meningeal gliomatosis (MG) have been produced by intracisternal inoculation of human glioma cell lines into nude mice. The tumor growth was steady and fast in MG nude mice if 10(7) cells were implanted. Median survival time (MST) of nude mice inoculated with tumor cells was inversely related to the number of cells inoculated. There was a correlation between in vitro and in vivo (MG models) growth rate, which means that the cell kinetics in vitro are reflected in vivo. The clinicopathological features observed in nude mouse MG models were similar to those seen in diffuse leptomeningeal involvement of gliomas in humans. The models will be useful for investigating the pathophysiology of meningeal gliomatosis and the efficacy of chemotherapeutic agents.
 ...
PMID:[Development of experimental meningeal gliomatosis models using nude mice]. 375 23

Glia maturation factor (GMF), a 14,000 Mr acidic protein of the brain, is capable of promoting differentiation of cultured astroblasts. In this study we report the effect of GMF on two glioma cell lines: the C6 line, of rodent origin, and the HG-1 line, of human origin. When tested in culture, GMF promotes the initial growth of the two cell lines when the cells are sparse but limits proliferation by restoring contact inhibition when the cells are confluent. Cell cycle analysis confirms the arrest of the cells at the G0/G1 phase when the tumor cells are contact inhibited by GMF. When C6 cells are inoculated into the athymic (nude) mice at a s.c. site, a single solid tumor grows out with a 100% take. Intraperitoneal injection of GMF leads to the slowing down of tumor growth. That the in vivo effect of GMF is not due to cytotoxicity is evidenced by the lack of necrosis and by the appearance of more mature astrocytic cells in the tumors. The results lend support to the concept of GMF as a cellular regulator and suggest the therapeutic potential of GMF for brain tumors.
 ...
PMID:Suppression of glioma growth in vitro and in vivo by glia maturation factor. 375 76

The effects of hematoporphyrin derivative, light, and cobalt 60 (60Co) irradiation were studied in a rat glioma model using an in vivo and an in vitro clonogenic assay. There was no effect on tumor growth by visible light or by a single dose of 60Co irradiation at 4 Gy or 8 Gy, whereas 16 Gy inhibited tumor growth to 40% versus the control. Hematoporphyrin derivative alone slightly stimulated growth (P less than 0.1). Light in the presence of 10 mg hematoporphyrin derivative/kg inhibited tumor growth to 32%. 60Co irradiation in the presence of hematoporphyrin derivative produced a significant tumor growth inhibition (P less than 0.02). This growth inhibition was directly related to the concentration of hematoporphyrin derivative. The addition of 60Co to light in the presence of hematoporphyrin derivative produced a greater growth inhibition than light or 60Co irradiation alone. This effect was most pronounced when light was applied 30 minutes before 60Co irradiation. Our experiments in a subcutaneous rat glioma model suggest a radiosensitizing effect of hematoporphyrin derivative. Furthermore, the photodynamic inactivation is enhanced by the addition of 60Co irradiation. These findings may be of importance in planning new treatment modalities in malignant brain tumors.
 ...
PMID:The interaction of hematoporphyrin derivative, light, and ionizing radiation in a rat glioma model. 394 32


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>