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)

Temozolomide, an oral cytotoxic agent with approximately 100% bioavailability after one administration, has demonstrated schedule-dependent clinical activity against highly resistant cancers. Thirty patients with minimal prior chemotherapy were enrolled in this phase I trial to characterize the drug's safety, pharmacokinetics and anti-tumour activity, as well as to assess how food affects oral bioavailability. To determine dose-limiting toxicities (DLT) and the maximum tolerated dose (MTD), temozolomide 100-250 mg m(-2) was administered once daily for 5 days every 28 days. The DLT was thrombocytopenia, and the MTD was 200 mg m(-2) day(-1). Subsequently, patients received the MTD to study how food affects the oral bioavailability of temozolomide. When given orally once daily for 5 days, temozolomide was well tolerated and produced a non-cumulative, transient myelosuppression. The most common non-haematological toxicities were mild to moderate nausea and vomiting. Clinical activity was observed against several advanced cancers, including malignant glioma and metastatic melanoma. Temozolomide demonstrated linear and reproducible pharmacokinetics and was rapidly absorbed (mean Tmax approximately 1 h) and eliminated (mean t1/2 = 1.8 h). Food produced a slight reduction (9%) in absorption of temozolomide. Temozolomide 200 mg m(-2) day(-1) for 5 days, every 28 days, is recommended for phase II studies.
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PMID:Phase I dose-escalation and pharmacokinetic study of temozolomide (SCH 52365) for refractory or relapsing malignancies. 1057 60

Malignant gliomas (glioblastoma multiforme and anaplastic astrocytoma) occur more frequently than other types of primary central nervous system tumors, having a combined incidence of 5-8/100,000 population. Even with aggressive treatment using surgery, radiation, and chemotherapy, median reported survival is less than 1 year. Temozolomide, a new drug, has shown promise in treating malignant gliomas and other difficult-to-treat tumors. Temozolomide, a p.o. imidazotetrazine second-generation alkylating agent, is the leading compound in a new class of chemotherapeutic agents that enter the cerebrospinal fluid and do not require hepatic metabolism for activation. In vitro, temozolomide has demonstrated schedule-dependent antitumor activity against highly resistant malignancies, including high-grade glioma. In clinical studies, temozolomide consistently demonstrates reproducible linear pharmacokinetics with approximately 100% p.o. bioavailability, noncumulative minimal myelosuppression that is rapidly reversible, and activity against a variety of solid tumors in both children and adults. Preclinical studies have evaluated the combination of temozolomide with other alkylating agents and inhibitors of the DNA repair protein O6-alkylguanine alkyltransferase to overcome resistance to chemotherapy in malignant glioma and malignant metastatic melanoma. Temozolomide has recently been approved in the United States for the treatment of adult patients with refractory anaplastic astrocytoma and, in the European Union, for treatment of glioblastoma multiforme showing progression or recurrence after standard therapy. Predictable bioavailability and minimal toxicity make temozolomide a candidate for a wide range of clinical testing to evaluate the potential of combination treatments in different tumor types. An overview of the mechanism of action of temozolomide and a summary of results from clinical trials in malignant glioma are presented here.
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PMID:Temozolomide and treatment of malignant glioma. 1091 98

KRN8602 (MX2) is a newly developed morpholino anthracycline that crosses the blood-brain barrier where it becomes distributed in brain tissue after intravenous administration. This morpholino anthracycline has been found to be effective against human glioma cells and the intracerebrally transplanted tumors in vivo, We performed a phase II trial using KRN8602 as a single agent in malignant glioma patients who had not received prior adjuvant therapy. The 13 patients (5 glioblastomas, 7 anaplastic astrocytomas and 1 malignant oligodendroglioma) enrolled received at least 1 cycle of KRN8602 at 35 mg/m2/day in 3-4 week intervals by intravenous bolus. Ten of these patients could be evaluated for response, and 13 for toxicity. Three patients (1 glioblastoma and 2 anaplastic astrocytomas) demonstrated a complete response (3/10, 30%). Concerning side effects, myelosuppression was moderately severe, with 30.7% of patients developing grade 3 leukopenia. Severe nausea/vomiting was observed in 69% of the patients, however, cardiotoxicity was not observed. The results indicate that KRN8602 demonstrated modest activity against malignant glioma with relatively severe, but manageable toxicity. Further assessment of the efficacy and toxicity of KRN8602 against malignant glioma may be worthwhile.
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PMID:Phase II trial of pre-irradiation KRN8602 (MX2) in malignant glioma patients. 1108 79

A Phase I trial of irinotecan was performed to determine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), and the incidence and severity of other toxicities in children with refractory solid tumors. Thirty-five children received 146 courses of irinotecan administered as a 60-min i.v. infusion, daily for 5 days, every 21 days, after premedication with dexamethasone and ondansetron. Doses ranged from 30 mg/m2 to 65 mg/m2. An MTD was defined in heavily pretreated and less-heavily pretreated (i.e., two prior chemotherapy regimens, no prior bone marrow transplantation, and no radiation to the spine, skull, ribs, or pelvic bones) patients. Myelosuppression was the primary DLT in heavily pretreated patients, and diarrhea was the DLT in less-heavily pretreated patients. The MTD in the heavily pretreated patient group was 39 mg/m2, and the MTD in the less-heavily pretreated patients was 50 mg/m2. Non-dose-limiting diarrhea that was well controlled and of brief duration was observed in approximately 75% of patients. A partial response was observed in one patient with neuroblastoma, and in one patient with hepatocellular carcinoma. Stable disease (4-20 cycles) was observed in seven patients with a variety of malignancies including neuroblastoma, pineoblastoma, glioblastoma, brainstem glioma, osteosarcoma, hepatoblastoma, and a central nervous system rhabdoid tumor. In conclusion, the recommended Phase II dose of irinotecan administered as a 60-min i.v. infusion daily for 5 days, every 21 days, is 39 mg/m2 in heavily treated and 50 mg/m2 in less-heavily treated children with solid tumors.
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PMID:A phase I study of irinotecan in pediatric patients: a pediatric oncology group study. 1120 14

Treosulfan is a bifunctional alkylating prodrug with activity against various solid tumors. To improve the outcome for patients with recurrent malignant glioma, we assessed the efficacy of intravenous treosulfan (6-10 g/m2 4-weekly) as salvage therapy for patients with recurrent or progressive glioblastoma (GB, n = 14) or anaplastic astrocytoma (AA, n = 2). All patients had prior involved-field radiotherapy and adjuvant nitrosourea-based chemotherapy. A total of 56 cycles were administered. Tumor responses were assessed radiologically and clinically prior to each cycle. All patients were assessable for toxicity, response and survival. There were no complete or partial responses (CR, PR). Two patients progressed after the first cycle, 14 patients had initially stable disease (SD). Median progression-free survival was 3.25 months for the GB patients. Five patients were progression-free at 6 months (30%), including the 2 AA patients. The 2 AA patients are stable at 22 months. Myelosuppression was the dose-limiting toxicity in this cohort of nitrosourea-pretreated patients. Treosulfan has modest activity in patients with recurrent malignant glioma. Further evaluation of treosulfan in chemonaive malignant glioma patients is warranted.
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PMID:Treosulfan chemotherapy for recurrent malignant glioma. 1121 2

The aims of this phase I study in patients with recurrent malignant gliomas were to determine the maximum tolerated dose (MTD) and toxicity profile of fotemustine when combined with a fixed dose of procarbazine (PCZ), and to evaluate the extent of O6-alkylguanine-DNA alkyltransferase (ATase) depletion in circulating lymphocytes during treatment. Sixteen patients received an induction cycle consisting of 100 mg/day oral PCZ for 12 consecutive days and a 1-h intravenous infusion of fotemustine given 4 h after PCZ on days 5 and 12 at escalated doses (50, 75, 100 and 125 mg/m2/day). After a 6-week rest period, a maximum of 4 maintenance cycles (PCZ 300 mg/day, 4 days; fotemustine, day 4) was given every 4 weeks. ATase activity was measured on days 1, 5 and 12 over 4 h after PCZ intake. Fifteen patients had previously received at least one nitrosourea-based chemotherapy, associated with PCZ in 12 cases. The MTD of fotemustine was 125 mg/m2 (days 5 and 12) with myelosuppression as the dose limiting toxicity (DLT). At this dose level, half of patients experienced grade 3 anemia, neutropenia or thrombopenia. No extra-hematological DLT was observed. No significant depletion of ATase activity by PCZ was evidenced. One partial response and 7 stable diseases were obtained leading to a disease control rate of 50%. The median times to progression and survival were 2.6 and 9.7 months, respectively. This combined regimen of PCZ and fotemustine was well tolerated with a good disease control rate in heavily pretreated glioma patients and merits further investigation in phase II studies.
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PMID:Fotemustine combined with procarbazine in recurrent malignant gliomas: a phase I study with evaluation of lymphocyte 06-alkylguanine-DNA alkyltransferase activity. 1150 14

Patients with malignant glioma undergo a combined treatment with surgical resection, radiotherapy, and chemotherapy. Although those treatments usually show some restraining effects on the tumor, a relapse occurs in most of the patients within a few years. We have investigated the feasibility and safety of intra-arterial chemotherapy for malignant brain tumors by enhancing vascular permeability using intra-arterial bradykinin infusion. In 2001, The Committee of Ethics in Kyushu University approved our clinical trial of the bradykinin-enhancing chemotherapy for recurrent malignant gliomas. We here report the first case of our clinical trial. A 31-year-old man, who had undergone surgical resection followed by chemotherapy and irradiation for malignant progression of the left frontal astrocytoma over a period of 2 years, had a relapse of the tumor in the bilateral frontal lobes. After obtaining informed consent, bradykinin and carboplatin were infused through a microcatheter at the left A1 portion under general anesthesia. By dose escalation of bradykinin, the enhanced lesion in the bilateral frontal lobes diminished on magnetic resonance imaging after 3 trials with 3-week intervals, regardless of new lesions outside of the treated area. No neurological or physiological complication including myelosuppression was noted. Bradykinin-enhancing chemotherapy appeared to be effective and safe for malignant glioma. Because it was able to increase drug delivery to the tumor, it was possible to reduce the size of the dose of chemotherapeutic agent, which resulted in minimum complication.
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PMID:[Clinical trial of bradykinin-enhancing chemotherapy for a recurrent malignant glioma: a case report]. 1175 19

A phase II study of irinotecan (CPT-11) was conducted at Duke University Medical Center, Durham, NC, to evaluate the activity of this agent in children with high-risk malignant brain tumors. A total of 22 children were enrolled in this study, including 13 with histologically verified recurrent malignant brain tumors (glioblastoma multiforme [GBM] 4, anaplastic astrocytoma 1, ependymoma 5, and medulloblastoma/primitive neuroectodermal tumor 3), 5 with recurrent diffuse pontine glioma, and 4 with newly diagnosed GBM. All patients with recurrent tumor had prior chemotherapy and/or irradiation. Each course of CPT-11 consisted of 125 mg/m ( 2 ) per week given i.v. for 4 weeks followed by a 2-week rest period. Patients with recurrent tumors received therapy until disease progression or unacceptable toxicity. Patients with newly diagnosed tumors initially received 3 cycles of treatment to assess tumor response and then were allowed radiotherapy at physician's choice; patients who demonstrated a response to CPT-11 prior to radiotherapy were allowed to continue the drug after radiation until disease progression or unacceptable toxicity. A 25% to 50% dose reduction was made for grade III-IV toxicity. Responses were assessed after every course by gadolinium-enhanced MRI of the brain and spine. Twenty-two patients received a median of 2 courses of CPT-11 (range, 1-16). Responses were seen in 4 of 9 patients with GBM or anaplastic astrocytoma (44%; 95% confidence interval, 11%-82%) (complete response in 2 patients with recurrent GBM lasting 9 months and 48+ months; partial response in one patient with a newly diagnosed midbrain GBM lasting 18 months prior to radiotherapy; and partial response lasting 11 months in 1 patient with recurrent anaplastic astrocytoma), 1 of 5 patients with recurrent ependymoma (partial response initially followed by stable disease lasting 11 months), and none of 5 patients with recurrent diffuse pontine glioma. Two of 3 patients with medulloblastoma/primitive neuroectodermal tumor had stable disease for 9 and 13 months. Toxicity was mainly myelosuppression, with 12 of 22 patients (50%) suffering grade II-IV neutropenia. Seven patients required dose reduction secondary to neutropenia. CPT-11, given in this schedule, appears to be active in children with malignant glioma, medulloblastoma, and ependymoma with acceptable toxicity. Ongoing studies will demonstrate if activity of CPT-11 can be enhanced when combined with alkylating agents, including carmustine and temozolomide.
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PMID:Phase II study of irinotecan (CPT-11) in children with high-risk malignant brain tumors: the Duke experience. 1191 1

Gliomas are the most common primary intracerebral tumours and over 60% of these are malignant. Standard treatment in the UK for patients with a good performance status consists of surgery and postoperative radiotherapy, however, recurrence is almost inevitable. Treatment of recurrent malignant gliomas (MG) is limited to further surgery, chemotherapy and novel biological therapies. The response rate to standard chemotherapy protocols for recurrent MG is less than 30%. Temozolomide (Temodar-US, Temodal-Rest of World) is an oral alkylating agent with a similar chemical structure to dacarbazine, and has recently been licensed in the UK for second line treatment of recurrent MG. Several phase II studies and one randomised trial suggest that Temozolomide improves time to progression and quality of life but not overall survival. The drug is well tolerated with dose limiting myelosuppression and thrombocytopenia occurring in less than 10% of patients at current dosage schedules. A randomised trial comparing Temozolomide with best first line adjuvant chemotherapy (PCV) is about to start recruiting patients. Further clinical studies investigating its role in neoadjuvant treatment or in combination with radiotherapy or other chemotherapeutic approaches are ongoing.
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PMID:The use of temozolomide in recurrent malignant gliomas. 1229 19

Temozolomide (TMZ) is currently being evaluated for the treatment of high-grade gliomas in children. Myelosuppression (the suppression of bone marrow activity) is the dose-limiting toxicity for TMZ in adults and children. Empirical methods (i.e. relations between the percent change in absolute neutrophil count (ANC) and the area under the plasma concentration curve (AUC) of TMZ or its active metabolite MTIC) showed poor results when attempting to describe myelosuppression from serial data derived during TMZ therapy in a Phase II study of children with high-grade glioma. Therefore, to improve our understanding of the myelosuppressive effects of TMZ and MTIC in children we developed a mechanistic mathematical model. The model describes the progression of neutrophils from their production in the bone marrow to their release in the plasma. Included in the model are the feedback effects of granulocyte colony stimulating factor (G-CSF), which stimulates neutrophil production when there is a decrease in circulating neutrophils. The model is fit to serial ANC measurements obtained after TMZ dosing and it is able to explain, among other things, the lag in ANC reduction following a dose of TMZ, the ANC nadir, and the 'rebound effect' observed where the ANC recovers to levels greater than that observed pre-TMZ dose. This model will be useful for the prospective design of clinical trials of TMZ in children with cancer.
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PMID:A mechanistic mathematical model of temozolomide myelosuppression in children with high-grade gliomas. 1452 45


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