0000000000353848

AUTHOR

Michael Weller

0000-0002-1748-174x

Differential expression of the tumor suppressor A-kinase anchor protein 12 in human diffuse and pilocytic astrocytomas is regulated by promoter methylation

The scaffold protein A-kinase anchor protein 12 (AKAP12) exerts tumor suppressor activity and is downregulated in several tumor entities. We characterized AKAP12 expression and regulation in astrocytomas, including pilocytic and diffusely infiltrating astrocytomas. We examined 194 human gliomas and 23 normal brain white matter samples by immunohistochemistry or immunoblotting for AKAP12 expression. We further performed quantitative methylation analysis of the AKAP12 promoter by MassARRAY® of normal brain, World Health Organization (WHO) grade I to IV astrocytomas, and glioma cell lines. Our results show that AKAP12 is expressed in a perivascular distribution in normal CNS, strongly upregula…

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O6-methylguanine DNA methyltransferase and p53 status predict temozolomide sensitivity in human malignant glioma cells

Temozolomide (TMZ) is a methylating agent which prolongs survival when administered during and after radiotherapy in the first-line treatment of glioblastoma and which also has significant activity in recurrent disease. O6-methylguanine DNA methyltransferase (MGMT) is a DNA repair enzyme attributed a role in cancer cell resistance to O6-alkylating agent-based chemotherapy. Using a panel of 12 human glioma cell lines, we here defined the sensitivity to TMZ in acute cytotoxicity and clonogenic survival assays in relation to MGMT, mismatch repair and p53 status and its modulation by dexamethasone, irradiation and BCL-X(L). We found that the levels of MGMT expression were a major predictor of T…

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ERGO: A pilot study of ketogenic diet in recurrent glioblastoma

Limiting dietary carbohydrates inhibits glioma growth in preclinical models. Therefore, the ERGO trial (NCT00575146) examined feasibility of a ketogenic diet in 20 patients with recurrent glioblastoma. Patients were put on a low-carbohydrate, ketogenic diet containing plant oils. Feasibility was the primary endpoint, secondary endpoints included the percentage of patients reaching urinary ketosis, progression-free survival (PFS) and overall survival. The effects of a ketogenic diet alone or in combination with bevacizumab was also explored in an orthotopic U87MG glioblastoma model in nude mice. Three patients (15%) discontinued the diet for poor tolerability. No serious adverse events attri…

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NOA-05 phase 2 trial of procarbazine and lomustine therapy in gliomatosis cerebri.

The NOA-05 multicenter trial was performed to analyze the efficacy of primary chemotherapy with procarbazine and lomustine (PC) in patients with gliomatosis cerebri (GC) and to define clinical, imaging, and molecular factors influencing outcome.Thirty-five patients with previously untreated GC were treated with up to six 56-day courses of 110mg/m(2) lomustine on day 1 and 60mg/m(2) procarbazine on days 8 to 21. The primary endpoint was the rate of patients without therapy failure (defined as progressive disease, death from any cause, or termination of PC therapy before the end of course 4) at 8 months after the beginning of PC chemotherapy.The failure-free survival rate at 8 months was 50.3…

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Randomized phase III study of whole-brain radiotherapy for primary CNS lymphoma

Objective: This is the final report of a phase III randomized study to evaluate whole-brain radiotherapy (WBRT) in primary therapy of primary CNS lymphoma (PCNSL) after a median follow-up of 81.2 months. Methods: Patients with newly diagnosed PCNSL were randomized to high-dose methotrexate (HDMTX)–based chemotherapy alone or followed by WBRT. We hypothesized that the omission of WBRT would not compromise overall survival (OS; primary endpoint), using a noninferiority design with a margin of 0.9. Results: In the per-protocol population (n = 320), WBRT nonsignificantly prolonged progression-free survival (PFS) (median 18.2 vs 11.9 months, hazard ratio [HR] 0.83 [95% confidence interval (CI) 0…

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CD133 expression is associated with small round blue cell tumour morphology in human central nervous system neoplasms

Schittenhelm J, Simon P, Harter P N, Zachskorn C, Schlaszus H, Rottger F, Winkels M, Weller M, Meyermann R & Mittelbronn M (2011) Histopathology58, 739–749 CD133 expression is associated with small round blue cell tumour morphology in human central nervous system neoplasms Aims:  CD133 is considered to be a marker for brain tumour-initiating cells. However, most data on CD133 are derived from animal or in-vitro studies. The aim of this study was to characterize CD133 expression, and the distribution and morphological features of CD133+ cells, in primary and secondary human central nervous system (CNS) neoplasms. Methods and results:  Tumours were analysed by real-time reverse transcription …

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Chemoradiotherapy of Newly Diagnosed Glioblastoma With Intensified Temozolomide

Purpose To evaluate the toxicity and efficacy of chemoradiotherapy with temozolomide (TMZ) administered in an intensified 1-week on/1-week off schedule plus indomethacin in patients with newly diagnosed glioblastoma. Patients and Methods A total of 41 adult patients (median Karnofsky performance status, 90%; median age, 56 years) were treated with preirradiation TMZ at 150 mg/m 2 (1 week on/1 week off), involved-field radiotherapy combined with concomitant low-dose TMZ (50 mg/m 2 ), maintenance TMZ starting at 150 mg/m 2 using a 1-week on/1-week off schedule, plus maintenance indomethacin (25 mg twice daily). Results The median follow-up interval was 21.7 months. Grade 4 hematologic toxicit…

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Lomustine-temozolomide combination therapy versus standard temozolomide therapy in patients with newly diagnosed glioblastoma with methylated MGMT promoter (CeTeG/NOA–09): a randomised, open-label, phase 3 trial

Summary Background There is an urgent need for more effective therapies for glioblastoma. Data from a previous unrandomised phase 2 trial suggested that lomustine-temozolomide plus radiotherapy might be superior to temozolomide chemoradiotherapy in newly diagnosed glioblastoma with methylation of the MGMT promoter. In the CeTeG/NOA-09 trial, we aimed to further investigate the effect of lomustine-temozolomide therapy in the setting of a randomised phase 3 trial. Methods In this open-label, randomised, phase 3 trial, we enrolled patients from 17 German university hospitals who were aged 18–70 years, with newly diagnosed glioblastoma with methylated MGMT promoter, and a Karnofsky Performance …

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