BACKGROUND: In 2004, a randomised phase III trial by the European Organisation for Research and Treatment of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trials Group (NCIC) reported improved median and 2-year survival for patients with glioblastoma treated with concomitant and adjuvant temozolomide and radiotherapy. We report the final results with a median follow-up of more than 5 years. METHODS: Adult patients with newly diagnosed glioblastoma were randomly assigned to receive either standard radiotherapy or identical radiotherapy with concomitant temozolomide followed by up to six cycles of adjuvant temozolomide. The methylation status of the methyl-guanine methyl transferase gene, MGMT, was determined retrospectively from the tumour tissue of 206 patients. The primary endpoint was overall survival. Analyses were by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT00006353. FINDINGS: Between Aug 17, 2000, and March 22, 2002, 573 patients were assigned to treatment. 278 (97%) of 286 patients in the radiotherapy alone group and 254 (89%) of 287 in the combined-treatment group died during 5 years of follow-up. Overall survival was 27.2% (95% CI 22.2-32.5) at 2 years, 16.0% (12.0-20.6) at 3 years, 12.1% (8.5-16.4) at 4 years, and 9.8% (6.4-14.0) at 5 years with temozolomide, versus 10.9% (7.6-14.8), 4.4% (2.4-7.2), 3.0% (1.4-5.7), and 1.9% (0.6-4.4) with radiotherapy alone (hazard ratio 0.6, 95% CI 0.5-0.7; p<0.0001). A benefit of combined therapy was recorded in all clinical prognostic subgroups, including patients aged 60-70 years. Methylation of the MGMT promoter was the strongest predictor for outcome and benefit from temozolomide chemotherapy. INTERPRETATION: Benefits of adjuvant temozolomide with radiotherapy lasted throughout 5 years of follow-up. A few patients in favourable prognostic categories survive longer than 5 years. MGMT methylation status identifies patients most likely to benefit from the addition of temozolomide. FUNDING: EORTC, NCIC, Nelia and Amadeo Barletta Foundation, Schering-Plough.

https://www.thelancet.com/pdfs/journals/lanonc/PIIS1470-2045(09)70025-7.pdf

Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomised phase III study: 5-year analysis of the EORTC-NCIC trial

background Epigenetic silencing of the MGMT (O 6 -methylguanine–DNA methyltransferase) DNArepair gene by promoter methylation compromises DNA repair and has been associated with longer survival in patients with glioblastoma who receive alkylating agents. methods We tested the relationship between MGMT silencing in the tumor and the survival of patients who were enrolled in a randomized trial comparing radiotherapy alone with radiotherapy combined with concomitant and adjuvant treatment with temozolomide. The methylation status of the MGMT promoter was determined by methylation-specific polymerase-chain-reaction analysis. results The MGMT promoter was methylated in 45 percent of 206 assessable cases. Irrespective of treatment, MGMT promoter methylation was an independent favorable prognostic factor (P<0.001 by the log-rank test; hazard ratio, 0.45; 95 percent confidence interval, 0.32 to 0.61). Among patients whose tumor contained a methylated MGMT promoter, a survival benefit was observed in patients treated with temozolomide and radiotherapy; their median survival was 21.7 months (95 percent confidence interval, 17.4 to 30.4), as compared with 15.3 months (95 percent confidence interval, 13.0 to 20.9) among those who were assigned to only radiotherapy (P=0.007 by the log-rank test). In the absence of methylation of the MGMT promoter, there was a smaller and statistically insignificant difference in survival between the treatment groups. conclusions Patients with glioblastoma containing a methylated MGMT promoter benefited from temozolomide, whereas those who did not have a methylated MGMT promoter did not have such a benefit.

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MGMT Gene Silencing and Benefit from Temozolomide in Glioblastoma

Glioblastoma multiforme (GBM) is the most common and lethal type of brain cancer. To identify the genetic alterations in GBMs, we sequenced 20,661 protein coding genes, determined the presence of amplifications and deletions using high-density oligonucleotide arrays, and performed gene expression analyses using next-generation sequencing technologies in 22 human tumor samples. This comprehensive analysis led to the discovery of a variety of genes that were not known to be altered in GBMs. Most notably, we found recurrent mutations in the active site of isocitrate dehydrogenase 1 (IDH1) in 12% of GBM patients. Mutations in IDH1 occurred in a large fraction of young patients and in most patients with secondary GBMs and were associated with an increase in overall survival. These studies demonstrate the value of unbiased genomic analyses in the characterization of human brain cancer and identify a potentially useful genetic alteration for the classification and targeted therapy of GBMs.

http://science.sciencemag.org/content/sci/321/5897/1807.full.pdf

An Integrated Genomic Analysis of Human Glioblastoma Multiforme

Background A recent genomewide mutational analysis of glioblastomas (World Health Organization [WHO] grade IV glioma) revealed somatic mutations of the isocitrate dehydrogenase 1 gene (IDH1) in a fraction of such tumors, most frequently in tumors that were known to have evolved from lower-grade gliomas (secondary glioblastomas). Methods We determined the sequence of the IDH1 gene and the related IDH2 gene in 445 central nervous system (CNS) tumors and 494 non-CNS tumors. The enzymatic activity of the proteins that were produced from normal and mutant IDH1 and IDH2 genes was determined in cultured glioma cells that were transfected with these genes. Results We identified mutations that affected amino acid 132 of IDH1 in more than 70% of WHO grade II and III astrocytomas and oligodendrogliomas and in glioblastomas that developed from these lower-grade lesions. Tumors without mutations in IDH1 often had mutations affecting the analogous amino acid (R172) of the IDH2 gene. Tumors with IDH1 or IDH2 mutations h...

/pdf/idh1-and-idh2-mutations-in-gliomas-1er88anbwg.pdf

IDH1 and IDH2 Mutations in Gliomas

Glioblastoma tumour cells release microvesicles (exosomes) containing mRNA, miRNA and angiogenic proteins. These microvesicles are taken up by normal host cells, such as brain microvascular endothelial cells. By incorporating an mRNA for a reporter protein into these microvesicles, we demonstrate that messages delivered by microvesicles are translated by recipient cells. These microvesicles are also enriched in angiogenic proteins and stimulate tubule formation by endothelial cells. Tumour-derived microvesicles therefore serve as a means of delivering genetic information and proteins to recipient cells in the tumour environment. Glioblastoma microvesicles also stimulated proliferation of a human glioma cell line, indicating a self-promoting aspect. Messenger RNA mutant/variants and miRNAs characteristic of gliomas could be detected in serum microvesicles of glioblastoma patients. The tumour-specific EGFRvIII was detected in serum microvesicles from 7 out of 25 glioblastoma patients. Thus, tumour-derived microvesicles may provide diagnostic information and aid in therapeutic decisions for cancer patients through a blood test.

https://www.ym.edu.tw/bps/paper/0317Glioblastoma.pdf

Glioblastoma microvesicles transport RNA and proteins that promote tumour growth and provide diagnostic biomarkers

The frequency of human herpesvirus 6 (HHV-6) DNA was assessed in autopsy material from multiple sclerosis (MS) plaques and normal-appearing white matter (NAWM) from brains of persons with MS, healthy brains, and brains of persons with other neurologic diseases. Specific areas from formalin-fixed, paraffin-embedded brain tissue samples were isolated by laser microscope. DNA was extracted from laser microdissected brain material, and HHV-6 genomic sequences were amplified by nested polymerase chain reaction. We analyzed 44 NAWM samples and 64 MS plaques from 13 patients with MS, 46 samples from 13 patients with non-MS neurologic disorders, and 41 samples from 12 healthy control brains. Of the 44 NAWM samples, 7 (15.9%) were positive for HHV-6 DNA sequences, versus 37 (57.8%) of 64 MS plaques (P<.0005). HHV-6 DNA was detected in 10 (21.7%) of 46 samples from patients with non-MS neurologic disorders and in 11 (26.8%) of 41 samples from patients without known neurologic disease. Although the frequency of HHV-6 DNA did not differ significantly by sample type, HHV-6 DNA was significantly more common in MS plaques, suggesting that HHV-6 may play a role in MS pathogenesis.

High Frequency of Human Herpesvirus 6 DNA in Multiple Sclerosis Plaques Isolated by Laser Microdissection

Remyelination of lesions in the central nervous system contributes to neural repair following clinical relapses in multiple sclerosis. Remyelination is initiated by recruitment and differentiation of oligodendrocyte progenitor cells (OPCs) into myelinating oligodendrocytes. Simvastatin, a blood-brain barrier-permeable statin in multiple sclerosis clinical trials, has been shown to impact the in vitro processes that have been implicated in remyelination. Animals were fed a cuprizone-supplemented diet for 6 weeks to induce localized demyelination in the corpus callosum; subsequent return to normal diet for 3 weeks stimulated remyelination. Simvastatin was injected intraperitoneally during the period of coincident demyelination and OPC maturation (weeks 4 to 6), throughout the entire period of OPC responses (weeks 4 to 9), or during the remyelination-only phase (weeks 7 to 9). Simvastatin treatment (weeks 4 to 6) caused a decrease in myelin load and both Olig2strong and Nkx2.2strong OPC numbers. Simvastatin treatment (weeks 4 to 9 and 7 to 9) caused a decrease in myelin load, which was correlated with a reduction in Nkx2.2strong OPCs and an increase in Olig2strong cells, suggesting that OPCs were maintained in an immature state (Olig2strong/Nkx2.2weak). NogoA+ oligodendrocyte numbers were decreased during all simvastatin treatment regimens. Our findings suggest that simvastatin inhibits central nervous system remyelination by blocking progenitor differentiation, indicating the need to monitor effects of systemic immunotherapies that can access the central nervous system on brain tissue-repair processes.

Statin Therapy Inhibits Remyelination in the Central Nervous System

Four septic patients and one asthmatic patient are described who developed a severe paralytic disorder in an intensive care unit (ICU), associated with a rise in serum creatine kinase and a severe necrotizing myopathy. All cases had received non-depolarizing muscle blocking agents and large intravenous doses of glucocorticoids. Three patients developed myoglobinuria. No improvement or very little improvement in muscle function was noted in the four fatal cases. The single survivor recovered his strength after 6 months. This syndrome ("necrotizing myopathy of intensive care") provides one of the differential diagnoses for ICU-acquired weakness. The myopathy appears to have several interdependent causes and it is proposed that these should be classified as myonecrosis "priming" factors (glucocorticoids, myotropic infections, sepsis) and "triggering" factors (non-depolarizing muscle blocking agents).

A syndrome of acute severe muscle necrosis in intensive care unit patients.

Recurrent demyelination was produced in mice by Cuprizone administration. During the second course of Cuprizone, the animals showed greater resistance to the toxin and demyelination occurred slowly and was complete only after prolonged periods. The earliest changes in oligodendrocytes occurred in the most distal processes, the inner cytoplasmic tongues, which showed degenerative changes 3 to 4 weeks before degeneration of the oligodendrocyte cell bodies or demyelination occurred. The results show for the first time that in demyelinating disease, a "dying-back" process similar to that described in axonal disease can affect the oligodendrocyte.

Evidence for a “dying‐back” gliopathy in demyelinating disease

/pdf/the-pathobiology-of-the-oligodendrocyte-54sumbpbk1.pdf

Samuel K. Ludwin

Papers

High Frequency of Human Herpesvirus 6 DNA in Multiple Sclerosis Plaques Isolated by Laser Microdissection

Statin Therapy Inhibits Remyelination in the Central Nervous System

A syndrome of acute severe muscle necrosis in intensive care unit patients.

Evidence for a “dying‐back” gliopathy in demyelinating disease

The Pathobiology of the Oligodendrocyte