Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The objective of the present study was to determine the frequency of amplifications of three different members of the erbB gene family in human glioblastoma multiforme (GBM). We investigated 47 glial tumors (37 GBM WHO grade IV, 5 anaplastic astrocytomas WHO III and 5 astrocytomas WHO II) by Southern and Western analysis, and immunocytochemistry. Gene amplification of erbB genes in human malignant gliomas was restricted to the EGF receptor (EGFR) gene, erbB-1. We found amplification of the EGFR gene in 49% (18/37) of GBM but not in the astrocytomas WHO II/III. The erbB-2 and erbB-3 genes showed no amplification in the tumor specimens investigated in this study. At the protein level we found overexpression of the EGF receptor in 86% (32/37) by Western analysis and in 92% (34/37) by immunocytochemistry. Expression of the ERBB2 protein was present in 54% (20/37) but immunoreactivity was much weaker than for EGF receptor and in most cases barely detectable by Western analysis and immunocytochemistry. The ERBB3 protein was not expressed in the glial tumors investigated in this study. Of the three erbB genes only gene amplification and overexpression of the EGF receptor seems to have an impact on tumor progression of human gliomas. Our data from immunohistochemistry indicate that ERBB2 expression in GBM is closely correlated with EGF receptor levels and is therefore not useful as an independent prognostic parameter.
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PMID:Amplification and differential expression of members of the erbB-gene family in human glioblastoma. 776 96

Clonal analysis of many human cancers have generally confirmed that they are monoclonal. Although astrocytic neoplasms are the most frequently occurring primary tumors in the central nervous system, their clonal composition has not been systematically studied. In this report, the clonal composition of 22 human astrocytomas of all histological grades (2 well-differentiated astrocytomas, 3 anaplastic astrocytomas and 17 glioblastoma multiforme) was determined by analysis of the pattern of X-chromosome inactivation. Leukocyte and non-tumor brain DNA were used as controls. In addition, specimens from different parts of four glioblastoma multiforme were analyzed to determine whether remote areas of the same tumor had the same clonal composition. Eighteen of nineteen informative astrocytomas had a monoclonal pattern of X-chromosome inactivation; one glioblastoma multiforme had loss of heterozygosity on the X chromosome. Specimens from different areas of the same tumor all had identical patterns of X-chromosome inactivation. Leukocytes and non-tumor brain used as controls uniformly had a polyclonal pattern of X-chromosome inactivation. Furthermore, loss of heterozygosity for chromosomes 10 or 17 p loci was found in 64% (9/14) of informative specimens and identical allelic patterns were observed in specimens from different areas of the same tumor. Our results demonstrate that human astrocytomas from low to high-grade are characterized by monoclonal cell populations. The presence of monoclonality in even low-grade neoplasms suggests that in astrocytic tumors the establishment of monoclonality occurs quite early. Also, the finding of a monoclonal pattern in intermediate- and high-grade astrocytomas further supports the hypothesis that clonal expansion underlies astrocytic tumor progression.
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PMID:Clonal analysis of human astrocytomas. 786 Nov 91

Between 1988 and 1991, eighty-six patients with glioblastoma multiforme were evaluated in order to define the influence of extent of surgery and tumor location on treatment outcome. Patients underwent surgery followed by postoperative hyperfractionated radiotherapy and chemotherapy delivered according to one of two consecutive protocols. Surgery consisted of biopsy in 25 (29%) patients and subtotal or gross total tumor resection in 61 (71%) patients. Frontally located tumors were noted in 26 (30%) patients and other tumor locations were noted in 60 (70%) patients. Patients having more radical surgery had longer median survival time (MST) and higher 1- and 2-year survival rates than those with biopsy only (56 vs 29 weeks, respectively; 62% and 23% vs 16% and 0%, respectively; p = 0.00000). Patients having frontally located tumors had longer MST and higher 1- and 2-year survival rates than those with other tumor locations (101 vs 47 weeks, respectively; 76% and 44% vs 37% and 2.5%, respectively; p = 0.00001). Multivariate analysis confirmed that extent of surgery and tumor location were independent prognostic factors in patients with glioblastoma multiforme. Regarding progression-free survival, patients having more radical surgery had longer median time to tumor progression (MTP) than those with biopsy only (33 weeks vs 21 weeks, respectively). Also, progression-free survival at 1 year was higher in radically resected group than in biopsy only group (20% vs 0%, respectively; p = 0.00000). Patients with frontally located tumors had longer MTP (42 weeks) and higher progression-free survival at 1 year (42%) than those with other tumor location (28 weeks and 1.7%, respectively; p = 0.00002).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of extent of surgery and tumor location on treatment outcome of patients with glioblastoma multiforme treated with combined modality approach. 786 Nov 94

We have analyzed DNA obtained from 10 glioblastomas multiforme and 6 astrocytomas for microsatellite instability, using 17 different microsatellite loci dispersed over 7 different chromosomes. Six of 16 gliomas showed 1 or more microsatellite alterations in tumor DNA as compared to constitutional DNA. We observed microsatellite instability resulting in allelic shifts in 5 of 10 glioblastomas multiforme but not in any of the astrocytomas. Loss of an allele was observed in 3 glioblastomas multiforme. An imbalance in the intensity of alleles was noticed in 1 astrocytoma and in 1 glioblastoma multiforme. In 1 glioblastoma multiforme, an extra allele was present at two distinct loci. Overall, 5.3% of microsatellite analyses showed an abnormality. We conclude that microsatellite instability is present at a low grade in glioblastomas multiforme but to a lesser extent in astrocytomas. Genomic instability in human gliomas, therefore, should not be regarded as a mechanism for tumor initiation but as an evolution in tumor progression.
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PMID:Instability of microsatellites in human gliomas. 788 63

Clinical characteristics and outcome in 57 patients with infiltrative thalamic astrocytomas were analyzed retrospectively. The median patient age was 22 years (range 1 to 69 years). Fourteen patients had no surgery, 37 had biopsy, and six had subtotal resection. The histological diagnosis was astrocytoma in 14 patients, anaplastic astrocytoma in 25, and glioblastoma multiforme in two; two specimens were nondiagnostic. The initial treatment was conventional radiation therapy (RT) in 20 patients (one also received interstitial brachytherapy), RT followed by chemotherapy in 18, hyperfractionated RT in 17 (one also received chemotherapy), and chemotherapy alone in two. The median time to tumor progression was 47 weeks (range 5 to 388 weeks); median survival was 73 weeks (range 11 to 502 weeks). Actuarial 1-, 2-, 3-, and 5-year survival rates were 67%, 35%, 24%, and 20%, respectively. Tumor progression was usually treated with chemotherapy. The assessed treatment failure was within 2 months after RT in 12 patients in whom the findings of the neurological and radiological examinations did not correspond. This assessment showed false-negative diagnosis of radiation-induced changes in five patients (42%); false-positive diagnosis of tumor progression could not be ascertained. In univariate Cox proportional-hazards analysis, histological diagnosis of astrocytoma, age under 18 years, and open biopsy were prognostically favorable features; in multivariate analysis, only open biopsy was favorable. Infiltrative astrocytomas of the thalamus carry a dismal prognosis, regardless of the type of treatment. Hyperfractionated RT does not increase toxicity but its benefit over conventional RT remains unproven.
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PMID:Infiltrative astrocytomas of the thalamus. 789 13

To characterize some of the genetic events underlying the development of glioblastoma multiforme, the authors analyzed 65 astrocytic tumors (seven pilocytic astrocytomas, eight astrocytomas, 16 anaplastic astrocytomas, and 34 glioblastomas multiforme) for loss of heterozygosity for chromosome 17p, loss of heterozygosity for chromosomes 10p and 10q, amplification of the epidermal growth factor receptor (EGFR) gene, and amplification of the oncogenes N-myc, c-myc, and N-ras using Southern blot analysis. Alterations of the p53 gene (positive immunostaining for p53 protein in tumors with or without p53 gene mutations) in these 65 tumors were analyzed previously. None of the 65 tumors showed amplification or rearrangement of N-myc, c-myc, or N-ras oncogenes. The molecular analysis presented here demonstrates distinct variants of astrocytic tumors, with at least three genetic pathways leading to glioblastoma multiforme. One pathway was characterized by 43 astrocytomas with alterations in p53. Glioblastomas with p53 alterations may represent tumors that progress from lower-grade astrocytomas. This variant was more likely to show loss of chromosome 17p than tumors without p53 alterations (p < 0.04). Seventy-five percent of tumors with loss of one 17p allele demonstrated mutations in the p53 gene. Loss of chromosome 10 was associated with progression from anaplastic astrocytoma (13%) to glioblastoma (38%) (p < 0.04). Amplification of the EGFR gene was a rare (7%) but late event in tumor progression (p < 0.03). A second pathway was characterized by six astrocytomas without p53 alterations and may represent clinically de novo high-grade tumors. These tumors were more likely to show amplification of the EGFR gene (83%) than tumors with p53 alterations. Sixty percent of tumors with EGFR amplification also showed loss of chromosome 10; loss of chromosome 17p was infrequent in this variant. One or more alternative pathways were characterized by 16 astrocytomas without p53 alterations and with none of the genetic changes analyzed in this study. Glioblastomas are a heterogeneous group of tumors that may arise via multiple genetic pathways.
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PMID:Pathways leading to glioblastoma multiforme: a molecular analysis of genetic alterations in 65 astrocytic tumors. 805 51

A non randomized pilot study has been undertaken to evaluate the feasibility of local immunotherapy (IT) of recurrent glioblastoma multiforme (GM) by continuous intracerebral perfusion of recombinant interleukin-2 (rIL-2, Eurocetus) with and without lymphokine activated killer (LAK) cells. At time of surgical removal of the tumor, a catheter was implanted in the cavity left by tumor debulking allowing continuous perfusion of rIL-2. Five patients received 18 x 10(6) IU/day or rIL-2 for five days. At days 1, 3, and 5 after surgery, rIL-2 perfusion was briefly interrupted for the injection of LAK cells. Eight other patients received rIL-2 alone, either 24 x 10(6) IU/day (five patients) or 54 x 10(6) IU/day (three patients). Capillary leak syndrome, which is the main side effect of systemic infusion of rIL-2, was never observed, but local immunotherapy induced fever, confusion, and cerebral edema in all patients. Despite local IT, tumor progression was diagnosed by CT scan 4 to 12 weeks after the treatment.
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PMID:Local immunotherapy of recurrent glioblastoma multiforme by intracerebral perfusion of interleukin-2 and LAK cells. 811 34

Twenty patients previously treated with surgery, radiation therapy and chemotherapy with a nitrosourea for malignant supratentorial gliomas received a combination of procarbazine, thiotepa and vincristine (P.T.V.) at tumor recurrence. Procarbazine was given at a dose of 100 mg/m2 per os from day 1 (D1) to day 15 (D15), thiotepa was administered i.v. at a dose of 35-45 mg/m2 at D1, and vincristine at a dose of 1.4 mg/m2 at D1 and D8. Courses of therapy were repeated every four weeks. Tolerance was evaluated in 20 patients. Three patients developed peripheral neuropathy after 2 or 3 courses of vincristine which was then discontinued. Blood toxicity over grade I occurred in 8 patients (40%). One patient developed a grade i.v. pancytopenia. All 20 patients could be evaluated for therapeutic response. A partial response was noted in 3 patients (15%): 1 glioblastoma multiforme, 1 anaplastic oligodendroglioma and 1 anaplastic astrocytoma. In these three patients time to tumor progression was 10, 11+ and 5 months, respectively. Stabilization lasting 4 months was observed in one patient (anaplastic astrocytoma). Estimated median duration of survival for the entire group was 4.5 months following the onset of PTV (13 months following the date of histology).
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PMID:Treatment of recurrent malignant supratentorial gliomas with the association of procarbazine, thiotepa and vincristine: a phase II study. 812 May 71

Reduced expression and/or allelic loss of the putative tumor suppressor gene DCC has been demonstrated in colorectal, gastric, pancreatic, esophageal, breast, and hematological malignancies. We examined the expression of the DCC gene in 22 tissue samples from human gliomas (glioblastoma multiforme, oligodendroglioma, and mixed oligodendroglioma/astrocytoma). Seven of 8 glioblastomas multiforme (88%) had reduced or absent DCC expression, and 8 of the other 14 tumors underexpressed DCC when compared to normal brain tissue. These results demonstrate that reduced expression of DCC occurs in human malignant gliomas and may be part of a common genetic pathway leading to neoplastic transformation and/or tumor progression.
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PMID:Expression of the tumor suppressor gene DCC in human gliomas. 824 11

Previous work has demonstrated the importance of the Protein Kinase C (PKC) signal transduction system in regulating the growth rate of malignant gliomas in vitro. Tamoxifen inhibits PKC in a minority of malignant gliomas within the micromolar concentration range in vitro, a property distinct from its estrogen receptor blockade effect. Tamoxifen was administered orally in very high dosages to 11 patients (9 males:2 females, age range 26-73, mean 45 years) with malignant gliomas (anaplastic astrocytoma or glioblastoma multiforme) who had failed treatment with external beam radiation therapy (and additional chemotherapy in 2). The dosage administered was estimated to be that necessary to achieve tissue concentrations within the low micromolar range, shown necessary to inhibit PKC in these tumors in vitro, and is approximately 5 times that used for standard antiestrogen therapy. Tumor reduction on radiographic images (MRI and PET [18FdG uptake]) with clinical improvement occurred in 3 patients; halting of tumor progression clinically and radiographically occurred in an additional patient. Of the remaining seven patients, three patients had marked and rapid progression of their disease despite treatment (dead after 3, 4, and 6 months respectively). Complications of treatment included a deep venous thrombosis requiring anticoagulation in one patient, nausea in one patient, and "hot-flashes" in a third patient. Tumor biopsy and measurement of tamoxifen and its active metabolite within the tumor of one patient (non-responder) showed levels within the middle of the in vitro therapeutic range. Follow-up of alive patients ranges from 4-18 months (mean 10 months). These encouraging preliminary results in a minority of these patients suggests some potential for this type of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Clinical and radiographic response in a minority of patients with recurrent malignant gliomas treated with high-dose tamoxifen. 838 28


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