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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study investigated the secretion of a tumor necrosis factor (TNF) and lymphotoxin (LT) from lymphokine-activated killer (LAK) cells during co-culture with glioblastoma cell lines, autologous glioma cells, and other non-gliomatous tumor cell lines (K562 and Daudi). Cytokine secretion from peripheral blood mononuclear cells (PBMC) was also examined. The TNF activity of culture supernatants was measured by L cell cytotoxic assay, and a neutralization test using anti-TNF and/or anti-LT antibodies determined whether the cytotoxic activity was due to TNF or LT. The results show that LAK cells secrete both TNF and LT during monoculture and release increased amounts of TNF and LT with non-gliomatous tumor cell stimulation, but PBMC secrete only TNF with tumor cell stimulation. Glioblastoma or anaplastic astrocytoma cells, however, did not stimulate cytokine secretion from either LAK cells or PBMC. This indicates a discrepancy between the capability of LAK cells to lyse malignant glioma cells and cytokine secretion from LAK cells, and suggests that malignant glioma cells may produce some factors which inhibit cytokine secretion from LAK cells.
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PMID:Analysis of tumor necrosis factor and lymphotoxin secreted by incubation of lymphokine-activated killer cells with tumor cells. 137 61

Tumor cells of a particular tissue may show a pattern of gene expression characteristic of the precursor cells of this tissue. To test this proposition for tumors of the central nervous system (CNS) we have used immunohistochemistry to analyze the expression of nestin in primary human CNS tumors and corresponding nonneoplastic brain tissue. Nestin defines a recently discovered sixth class of intermediate filament proteins and in the rat is expressed predominantly in CNS stem cells. In the adult nonneoplastic human brain we have detected only nestin expression in occasional endothelial cells. In contrast, a variety of primary CNS tumors contained substantially elevated nestin levels. The nestin-positive cells in the tumor tissue were tumor cells and/or endothelial cells. Glioblastomas expressed higher nestin levels than less malignant gliomas. This may indicate a correlation between nestin expression and malignancy within the glioma tumor group. In the primitive neuroectodermal class of tumors we observed both nestin-expressing and nonexpressing tumors, suggesting that nestin expression could be used to further characterize this complex and heterogeneous tumor group. Nine metastatic carcinomas were studied, and none showed nestin immunoreactivity in tumor cells. In conclusion, our data support the notion that primary CNS tumors share gene expression patterns with primitive, undifferentiated CNS cells and that nestin, like other intermediate filaments, may be useful in tumor diagnosis.
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PMID:Expression of the class VI intermediate filament nestin in human central nervous system tumors. 138 41

ImuVert, a new biological response modifier, was evaluated for toxicity and potential efficacy in patients with advanced cancer. This agent consists of sized, labile, natural membrane vesicles associated with ribosomes derived from Serratia marcescens. ImuVert induces enhanced in vitro macrophage and natural-killer-cell-mediated cytotoxicity, and has demonstrated antitumor activity in palpable animal tumor systems. A group of 39 patients with a variety of tumors, 25 men, 14 women, with a mean performance status (Karnofsky) of 80% and median age of 57 years were entered into this trial. ImuVert was administered subcutaneously weekly for a minimum of 3 weeks. A total of 183 treatments were evaluated. Flu-like systemic toxicities, including fever, chills, nausea, vomiting, diarrhea and hypotension were observed. Erythema, induration and tenderness developed at the injection sites. Myelosuppression, thrombocytopenia, anaphylaxis, rental and hepatic toxicities did not occur. All symptoms resolved within 24 h. Two patients with nodular lymphoma achieved a partial response and two minor responses were seen in patients with glioblastoma and melanoma. On the basis of ImuVert's biological activity, and tolerable toxicity it warrants further clinical investigation.
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PMID:Phase I trial of ImuVert (natural membrane vesicles associated with ribosomes) in patients with advanced cancer. 139 37

Conditional expression of wild-type (wt) p53 protein in a glioblastoma tumor cell line has been shown to be growth inhibitory. We have now more precisely localized the position in the cell cycle where growth arrest occurs. We show that growth arrest occurs prior to or near the restriction point in late G1 phase of the cell cycle. The effect of wt p53 protein on the expression of four immediate-early genes (c-FOS, c-JUN, JUN-B, and c-MYC), one delayed-early gene (ornithine decarboxylase), and two late-G1/S-phase genes (B-MYB and DNA polymerase alpha) was also examined. Of this subset of growth response genes, only the expression of B-MYB and DNA polymerase alpha was significantly repressed. The possibility that decreased expression of B-MYB may be an important component of growth arrest mediated by wt p53 protein is discussed.
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PMID:Growth arrest induced by wild-type p53 protein blocks cells prior to or near the restriction point in late G1 phase. 140 26

Experiments were performed using an established human glioblastoma cell line to determine the effect of lipoproteins on regulating their growth. It was found that synthetic and natural human high density lipoproteins (HDL) were effective in inhibiting tumor cell growth in a nontoxic, dose-dependent manner, and that the LD50 was 10-fold lower than that for normal rat astrocytes grown under identical conditions. In the presence of the antioxidant, glutathione, essentially all of the growth-inhibiting properties of HDL could be reversed suggesting that oxidized lipids from the HDL interacting with the plasma membranes of the glioblastoma cells were responsible for the growth-inhibiting effect observed. The markedly lower concentration of HDL required to inhibit glioblastoma cells in culture compared to normal astrocytes suggested that the mechanism of HDL-induced inhibition may be important for tumor growth in vivo. One possible mechanism under investigation is the possibility of HDL modulation of a membrane-associated, tumor-specific phosphatase.
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PMID:The effect of lipoproteins on human glioblastoma growth in vitro. 141 23

A total of 307 adult patients with glioma were treated with high-activity removable iodine-125 interstitial brain implants at the University of California at San Francisco from December 1979 to June 1990. Recurrent gliomas underwent brain implant alone whereas previously untreated (primary) tumors underwent brain implant boost after external beam radiotherapy. Of these patients, 106 had primary glioblastoma multiforme, 68 had primary non-glioblastoma glioma, 66 had recurrent glioblastoma multiforme and 67 had recurrent nonglioblastoma glioma. Median follow-up for living patients was 143 weeks. Median survival from diagnosis for primary glioblastoma multiforme and high and low grade nonglioblastoma glioma was 88 weeks, 142 weeks, and 226 weeks, respectively. Median survival measured from the date of implant for recurrent glioblastoma multiforme and high and low grade nonglioblastoma glioma was 49 weeks, 52 weeks, and 81 weeks, respectively. Ninety-two percent of patients had no toxicity or transient acute side effects. Severe acute toxicity was seen in 6% of patients, life threatening acute toxicity in 1% of patients, and fatal toxicity in less than 1% of patients. Forty percent of patients with malignant glioma underwent reoperation at a median of 33 weeks after brain implant, with tumor found in 95% of specimens at reoperation. This large experience demonstrates that interstitial implant is well-tolerated and prolongs survival in patients with primary and recurrent glioblastoma multiforme, as evidenced by the 3-year survival rates of 22% and 15%, respectively.
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PMID:High activity iodine-125 interstitial implant for gliomas. 142 79

Here I discuss quantitative and qualitative activation of several receptor-type molecules in tumor cells. Recently we have shown that EGF-R gene is frequently mutated in human glioblastoma. Mutant EGF-R had a 801-bp deletion within the ligand binding domain, and showed a ligand-independent, constitutive elevation of tyrosine kinase activity. This EGF-R mutation is detected only in glioma and associated with gene amplification, suggesting a relationship in the molecular mechanism between deletion mutation and initiation of gene amplification in these cases. Secondly I have shown an activation of mouse CD43 gene by amplification and rearrangement in erythroleukemia cell lines. Intracellular domain of CD43 has no kinase domain but a highly conserved structure among mammals, probably interacting with intracellular signal transducers. Recently CD43 has been demonstrated to be specifically associated with a cell-adhesion molecule ICAM-1. Thus, CD43-ICAM-1 system might be a new type of cytokine system which regulate cell-proliferation through cell-cell interaction. In addition, activation of EpoR and v-mpl is also discussed.
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PMID:[Membrane receptors and cell transformation]. 143 60

The effects of radiation on direction on directional migration in monolayer cultures and brain tissue invasion by two glioblastoma cell lines (D-54 MG, D-247 MG) were investigated. The Leksell Gamma Unit was the radiation source and invasion was registered in an in vitro invasion assay developed in our laboratory. As tumor spheroids and brain tissue aggregates were treated simultaneously in cocultures; the effects of radiation on the interaction between the two tissues could be investigated. Tumor spheroids from both cell lines retained their ability to invade and destroy normal brain tissue, even after irradiation with 47.6 Gy. However, while the D-54 MG tumor spheroids showed a dose-dependent reduction of invasion, tumor spheroids from the D-247 MG cell line did not. In addition, radiation produced a dose dependent inhibition of directional migration of cells from D-54 MG spheroids. A similar significant inhibition of directional migration was found in D-247 MG, but it was not dose-dependent. Transmission electron microscopy revealed a loosening of the neuropil in the brain tissue of irradiated cocultures. However, this structural change did not seem to affect the invasiveness of the tumor. In this preliminary study, irradiation could not prevent invasion of two different glioblastoma cell lines into fetal rat brain tissue. Further studies using the same technique may help to understand the influence of ionizing radiation upon the invasion process in gliomas.
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PMID:Effects of high and low single dose irradiation on glioma spheroid invasion into normal rat brain tissue in vitro. 144 12

This paper reports clinicopathological findings concerning an enlarged bulky cyst and the tumor cavity following local administration of an anticancer agent combined with radiotherapy in two patients suffering from malignant glioma. Case 1: This 69 year-old man who had been diagnosed as having glioblastoma in the right parietal lobe had received local chemotherapy after the first operation. Simultaneously radiotherapy of 69 Gy in total dose was performed. At the second operation for the tumor, cyst formation was clinically confirmed and necrotomy as well as evacuation of the large cyst was performed after adjuvant therapy. The patient died at a time ten months after the first surgical operation. Case 2: This is the case of a 48 year-old man who was diagnosed as having gemistocytic astrocytoma in the left frontal lobe. The first surgical operation was performed and was followed by local chemotherapy as well as radiotherapy (total dose of 90 Gy in two sessions). The second surgical operation of the recurrent tumor, with necrotomy and evacuation of the large cyst were performed after adjuvant therapy. The patient expired at a time sixty-five months after the first surgical operation. Relevant to the chemotherapy, adriamycin (ADM) (0.5mg) and methotrexate (MTX) (1mg) were administered through the Ommaya's reservoir into the tumor bed at craniotomy. The usual doses of ADM and MTX amounted to 5.0mg respectively. Through conventional CT and MRI, formation of a cyst including abundant membranous debris or septi was identified in both cases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Cyst formation following local chemotherapy of malignant brain tumor: a clinicopathological study of two cases]. 144 92

Beginning in 1986, using software to optimize radiation dosimetry, we have stereotactically placed removable catheters containing high activity I-125 sources into malignant gliomas in 56 patients. There were 32 men and 24 women, age 7 to 73. Forty-four had glioblastoma multiforme, and 12 anaplastic astrocytoma. Mean Karnofsky performance score was 75, range 50-100. Twenty patients (all with glioblastoma) were implanted after resection before further therapy, and 36 were implanted at recurrence following resection, external irradiation and chemotherapy. Six thousand cGy was delivered to the enhancing tumor contour on CT scan. Mean dose rate was 37 cGy/hr. Mean tumor volume was 41 cc, range 5-187 cc. Mean volume of brain that received 60 cGy was 67 cc, range 11-184 cc. Of 20 patients treated after resection alone, 8 are alive, 3-43 months after implantation; median survival is 22 months. Of 36 patients treated at recurrence, 14 are alive, 0-19 months after implantation; median survival is 10 months. The most common side effect of the procedure, which occurred in five patients, was catheter misplacement. Twenty-four patients (43%) required 27 reoperations, 1-25 months after implantation. In 25 pathologic specimens available for review, microscopic tumor foci with substantial radiation necrosis were found in 18, radiation necrosis only was noted in 5, and glioma alone was seen in 2.
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PMID:Interstitial irradiation of malignant gliomas. 144 65


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