Astrid Weyerbrock

Cilengitide combined with standard treatment for patients with newly diagnosed glioblastoma with methylated MGMT promoter (CENTRIC EORTC 26071-22072 study): a multicentre, randomised, open-label, phase 3 trial

BACKGROUND Cilengitide is a selective αvβ3 and αvβ5 integrin inhibitor. Data from phase 2 trials suggest that it has antitumour activity as a single agent in recurrent glioblastoma and in combination with standard temozolomide chemoradiotherapy in newly diagnosed glioblastoma (particularly in tumours with methylated MGMT promoter). We aimed to assess cilengitide combined with temozolomide chemoradiotherapy in patients with newly diagnosed glioblastoma with methylated MGMT promoter. METHODS In this multicentre, open-label, phase 3 study, we investigated the efficacy of cilengitide in patients from 146 study sites in 25 countries. Eligible patients (newly diagnosed, histologically proven supratentorial glioblastoma, methylated MGMT promoter, and age ≥18 years) were stratified for prognostic Radiation Therapy Oncology Group recursive partitioning analysis class and geographic region and centrally randomised in a 1:1 ratio with interactive voice response system to receive temozolomide chemoradiotherapy with cilengitide 2000 mg intravenously twice weekly (cilengitide group) or temozolomide chemoradiotherapy alone (control group). Patients and investigators were unmasked to treatment allocation. Maintenance temozolomide was given for up to six cycles, and cilengitide was given for up to 18 months or until disease progression or unacceptable toxic effects. The primary endpoint was overall survival. We analysed survival outcomes by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00689221. FINDINGS Overall, 3471 patients were screened. Of these patients, 3060 had tumour MGMT status tested; 926 patients had a methylated MGMT promoter, and 545 were randomly assigned to the cilengitide (n=272) or control groups (n=273) between Oct 31, 2008, and May 12, 2011. Median overall survival was 26·3 months (95% CI 23·8-28·8) in the cilengitide group and 26·3 months (23·9-34·7) in the control group (hazard ratio 1·02, 95% CI 0·81-1·29, p=0·86). None of the predefined clinical subgroups showed a benefit from cilengitide. We noted no overall additional toxic effects with cilengitide treatment. The most commonly reported adverse events of grade 3 or worse in the safety population were lymphopenia (31 [12%] in the cilengitide group vs 26 [10%] in the control group), thrombocytopenia (28 [11%] vs 46 [18%]), neutropenia (19 [7%] vs 24 [9%]), leucopenia (18 [7%] vs 20 [8%]), and convulsion (14 [5%] vs 15 [6%]). INTERPRETATION The addition of cilengitide to temozolomide chemoradiotherapy did not improve outcomes; cilengitide will not be further developed as an anticancer drug. Nevertheless, integrins remain a potential treatment target for glioblastoma. FUNDING Merck KGaA, Darmstadt, Germany.

NFKBIA Deletion in Glioblastomas

BACKGROUND Amplification and activating mutations of the epidermal growth factor receptor (EGFR) oncogene are molecular hallmarks of glioblastomas. We hypothesized that deletion of NFKBIA (encoding nuclear factor of κ-light polypeptide gene enhancer in B-cells inhibitor-α), an inhibitor of the EGFR-signaling pathway, promotes tumorigenesis in glioblastomas that do not have alterations of EGFR. METHODS We analyzed 790 human glioblastomas for deletions, mutations, or expression of NFKBIA and EGFR. We studied the tumor-suppressor activity of NFKBIA in tumor-cell culture. We compared the molecular results with the outcome of glioblastoma in 570 affected persons. RESULTS NFKBIA is often deleted but not mutated in glioblastomas; most deletions occur in nonclassical subtypes of the disease. Deletion of NFKBIA and amplification of EGFR show a pattern of mutual exclusivity. Restoration of the expression of NFKBIA attenuated the malignant phenotype and increased the vulnerability to chemotherapy of cells cultured from tumors with NFKBIA deletion; it also reduced the viability of cells with EGFR amplification but not of cells with normal gene dosages of both NFKBIA and EGFR. Deletion and low expression of NFKBIA were associated with unfavorable outcomes. Patients who had tumors with NFKBIA deletion had outcomes that were similar to those in patients with tumors harboring EGFR amplification. These outcomes were poor as compared with the outcomes in patients with tumors that had normal gene dosages of NFKBIA and EGFR. A two-gene model that was based on expression of NFKBIA and O(6)-methylguanine DNA methyltransferase was strongly associated with the clinical course of the disease. CONCLUSIONS Deletion of NFKBIA has an effect that is similar to the effect of EGFR amplification in the pathogenesis of glioblastoma and is associated with comparatively short survival.

Chloroquine or chloroquine-PI3K/Akt pathway inhibitor combinations strongly promote γ-irradiation-induced cell death in primary stem-like glioma cells.

We asked whether inhibitors of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, which is highly active in cancer stem cells (CSCs) and upregulated in response to genotoxic treatments, promote γ-irradiationγIR)-induced cell death in highly radioresistant, patient-derived stem-like glioma cells (SLGCs). Surprisingly, in most cases the inhibitors did not promote γIR-induced cell death. In contrast, the strongly cytostatic Ly294002 and PI-103 even tended to reduce it. Since autophagy was induced we examined whether addition of the clinically applicable autophagy inhibitor chloroquine (CQ) would trigger cell death in SLGCs. Triple therapy with CQ at doses as low as 5 to 10 µM indeed caused strong apoptosis. At slightly higher doses, CQ alone strongly promoted γIR-induced apoptosis in all SLGC lines examined. The strong apoptosis in combinations with CQ was invariably associated with strong accumulation of the autophagosomal marker LC3-II, indicating inhibition of late autophagy. Thus, autophagy-promoting effects of PI3K/Akt pathway inhibitors apparently hinder cell death induction in γ-irradiated SLGCs. However, as we show here for the first time, the late autophagy inhibitor CQ strongly promotes γIR-induced cell death in highly radioresistant CSCs, and triple combinations of CQ, γIR and a PI3K/Akt pathway inhibitor permit reduction of the CQ dose required to trigger cell death.

Cytokine Production during Sleep and Wakef ulness and Its Relationship to Cortisol in Healthy Humans

A growing body of evidence indicates that cytokines, especially interleukin-1 beta, are involved in the regulation of sleep and wakefulness. The aim of the present pilot study was to investigate the relationship between interleukin-1 beta (IL-1 beta) and gamma-interferon (gamma-IFN) production and the regulation of sleep and wakefulness. Four healthy male volunteers were investigated. After one adaptation night, beginning at 8 a.m. in the morning, the EEG was recorded by means of a mobile long-term EEG and blood samples were drawn every 45 min for the analysis of IL-1 beta, gamma-IFN and cortisol for 24 h. For the analysis of cytokines whole blood cultures were established. After 48 h of incubation in the presence of endotoxin Salmonella typhimurium, IL-1 beta and gamma-IFN levels were measured in the culture supernatants using specific immunodetection assays. Methods of stochastic time series analysis were adopted to evaluate the biochemical data. Our results show the capability of cultured blood cells to produce cytokines upon endotoxin challenge to be at a maximum around the time of sleep onset and during the first hours of sleep, declining during the night to a minimum level in the morning hours. The opposite was observed for cortisol. The analysis of autocorrelation functions gives evidence of a 24-hour rhythm of cortisol and cytokines. The results indicate that the cytokines IL-1 beta and gamma-IFN may play a role in sleep regulation.

Bevacizumab treatment induces metabolic adaptation toward anaerobic metabolism in glioblastomas

Anti-angiogenic therapy in glioblastoma (GBM) has unfortunately not led to the anticipated improvement in patient prognosis. We here describe how human GBM adapts to bevacizumab treatment at the metabolic level. By performing 13C6-glucose metabolic flux analysis, we show for the first time that the tumors undergo metabolic re-programming toward anaerobic metabolism, thereby uncoupling glycolysis from oxidative phosphorylation. Following treatment, an increased influx of 13C6-glucose was observed into the tumors, concomitant to increased lactate levels and a reduction of metabolites associated with the tricarboxylic acid cycle. This was confirmed by increased expression of glycolytic enzymes including pyruvate dehydrogenase kinase in the treated tumors. Interestingly, l-glutamine levels were also reduced. These results were further confirmed by the assessment of in vivo metabolic data obtained by magnetic resonance spectroscopy and positron emission tomography. Moreover, bevacizumab led to a depletion in glutathione levels indicating that the treatment caused oxidative stress in the tumors. Confirming the metabolic flux results, immunohistochemical analysis showed an up-regulation of lactate dehydrogenase in the bevacizumab-treated tumor core as well as in single tumor cells infiltrating the brain, which may explain the increased invasion observed after bevacizumab treatment. These observations were further validated in a panel of eight human GBM patients in which paired biopsy samples were obtained before and after bevacizumab treatment. Importantly, we show that the GBM adaptation to bevacizumab therapy is not mediated by clonal selection mechanisms, but represents an adaptive response to therapy.

Bevacizumab Plus Irinotecan Versus Temozolomide in Newly Diagnosed O6-Methylguanine–DNA Methyltransferase Nonmethylated Glioblastoma: The Randomized GLARIUS Trial

PURPOSE In patients with newly diagnosed glioblastoma that harbors a nonmethylated O(6)-methylguanine-DNA methyltransferase promotor, standard temozolomide (TMZ) has, at best, limited efficacy. The GLARIUS trial thus explored bevacizumab plus irinotecan (BEV+IRI) as an alternative to TMZ. PATIENTS AND METHODS In this phase II, unblinded trial 182 patients in 22 centers were randomly assigned 2:1 to BEV (10 mg/kg every 2 weeks) during radiotherapy (RT) followed by maintenance BEV (10 mg/kg every 2 weeks) plus IRI(125 mg/m(2) every 2 weeks) or to daily TMZ (75 mg/m(2)) during RT followed by six courses of TMZ (150-200 mg/m(2)/d for 5 days every 4 weeks). The primary end point was the progression-free survival rate after 6 months (PFS-6). RESULTS In the modified intention-to-treat (ITT) population, PFS-6 was increased from 42.6% with TMZ (95% CI, 29.4% to 55.8%) to 79.3% with BEV+IRI (95% CI, 71.9% to 86.7%; P <.001). PFS was prolonged from a median of 5.99 months (95% CI, 2.7 to 7.3 months) to 9.7 months (95% CI, 8.7 to 10.8 months; P < .001). At progression, crossover BEV therapy was given to 81.8% of all patients who received any sort of second-line therapy in the TMZ arm. Overall survival (OS) was not different in the two arms: the median OS was 16.6 months (95% CI, 15.4 to 18.4 months) with BEV+IRI and was 17.5 months (95% CI, 15.1 to 20.5 months) with TMZ. The time course of quality of life (QOL) in six selected domains of the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire (QLQ) -C30 and QLQ-BN20 (which included cognitive functioning), of the Karnofsky performance score, and of the Mini Mental State Examination score was not different between the treatment arms. CONCLUSION BEV+IRI resulted in a superior PFS-6 rate and median PFS compared with TMZ. However, BEV+IRI did not improve OS, potentially because of the high crossover rate. BEV+IRI did not alter QOL compared with TMZ.

Endothelial cell‐derived angiopoietin‐2 is a therapeutic target in treatment‐naive and bevacizumab‐resistant glioblastoma

Glioblastoma multiforme (GBM) is treated by surgical resection followed by radiochemotherapy. Bevacizumab is commonly deployed for anti‐angiogenic therapy of recurrent GBM; however, innate immune cells have been identified as instigators of resistance to bevacizumab treatment. We identified angiopoietin‐2 (Ang‐2) as a potential target in both naive and bevacizumab‐treated glioblastoma. Ang‐2 expression was absent in normal human brain endothelium, while the highest Ang‐2 levels were observed in bevacizumab‐treated GBM. In a murine GBM model, VEGF blockade resulted in endothelial upregulation of Ang‐2, whereas the combined inhibition of VEGF and Ang‐2 leads to extended survival, decreased vascular permeability, depletion of tumor‐associated macrophages, improved pericyte coverage, and increased numbers of intratumoral T lymphocytes. CD206+ (M2‐like) macrophages were identified as potential novel targets following anti‐angiogenic therapy. Our findings imply a novel role for endothelial cells in therapy resistance and identify endothelial cell/myeloid cell crosstalk mediated by Ang‐2 as a potential resistance mechanism. Therefore, combining VEGF blockade with inhibition of Ang‐2 may potentially overcome resistance to bevacizumab therapy.

Cilengitide combined with standard treatment for patients with newly diagnosed glioblastoma and methylated O6-methylguanine-DNA methyltransferase (MGMT) gene promoter: Key results of the multicenter, randomized, open-label, controlled, phase III CENTRIC study.

LBA2009 Background: Cilengitide (CIL) is a selective αvβ3 and αvβ5 integrin inhibitor. In a phase II study in patients with newly diagnosed glioblastoma, CIL added to standard temozolomide (TMZ) and radiotherapy (RT) was well tolerated and appeared to confer improved survival in patients with glioblastoma and methylated MGMT gene promoter (Stupp et al. J Clin Oncol. 2010;28:2712-8). METHODS This multicenter, randomized, controlled, open-label, phase III study randomized (1:1) patients (≥ 18 years) with newly diagnosed, histologically proven supratentorial glioblastoma (WHO Grade IV) and centrally determined MGMT gene promoter methylation. Treatment consisted of CIL 2000 mg twice weekly i.v. plus standard TMZ/RT→TMZ (concomitant and adjuvant temozolomide and radiotherapy; Stupp et al. N Engl J Med. 2005;352:987-96) or standard TMZ/RT→TMZ alone. CIL was to be administered for ≥ 18 months, or until disease progression or unacceptable toxicity. Primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS) per investigator read and safety. RESULTS 272 patients received CIL plus TMZ/RT→TMZ, and 273 were treated with TMZ/RT→TMZ alone (intention-to-treat population). 54% and 52% of patients were male, and 42% and 44% had ECOG-PS ≥ 1, respectively. 75% of patients of both arms were ≥ 50 years old. Overall, baseline characteristics were well balanced across treatment arms. Median OS was 26.3 months in both arms (Hazard Ratio [HR] = 1.02 [95%CI: 0.81-1.29], p = 0.86). Median PFS per investigator read was 13.5 months in the CIL arm and 10.7 months in the control arm (HR = 0.93 [95%CI: 0.76-1.14], p = 0.48). Treatment was generally well tolerated and the known safety profile of CIL was confirmed. CONCLUSIONS CIL failed to prolong PFS or OS in patients with newly diagnosed glioblastoma and methylated MGMT gene promoter. The previously reported safety profile of CIL in addition to standard therapy was confirmed. CLINICAL TRIAL INFORMATION NCT00689221.

Residual Tumor Volume as Best Outcome Predictor in Low Grade Glioma - A Nine-Years Near-Randomized Survey of Surgery vs. Biopsy.

Diffuse low grade gliomas (DLGG) are continuously progressive primary brain neoplasms that lead to neurological deficits and death. Treatment strategies are controversial. Randomized trials establishing the prognostic value of surgery do not exist. Here, we report the results of a nine-year near-randomized patient distribution between resection and biopsy. Until 2012, the Department of Neurosurgery and the Department of Stereotactic Neurosurgery at the University Medical Center Freiburg were organized as separate administrative units both coordinating DLGG patient treatment independently. All consecutive adult patients with a new diagnosis of DLGG by either stereotactic biopsy or resection were included. Pre- and post-operative tumor volumetry was performed. 126 patients, 87 men (69%), 39 women (31%), median age 41 years, were included. 77 (61%) were initially managed by biopsy, 49 (39%) by resection. A significant survival benefit was found for patients with an initial management by resection (5-year OS 82% vs. 54%). The survival benefit of patients with initial resection was reserved to patients with a residual tumor volume of less than 15 cm3. Maximum safe resection is the first therapy of choice in DLGG patients if a near-complete tumor removal can be achieved. Accurate prediction of the extent-of-resection is required for selection of surgical candidates.

Bevacizumab, irinotecan, and radiotherapy versus standard temozolomide and radiotherapy in newly diagnosed, MGMT-nonmethylated glioblastoma patients: First results from the randomized multicenter GLARIUS trial.

LBA2000 Background: In patients with MGMT-nonmethylated glioblastoma (GBM), primary chemotherapy with temozolomide (TMZ) is at best moderately effective. There is an urgent need for more effective therapies in this large subgroup of GBM. Since results of phase II trials with the antiangiogenic agent bevacizumab (BEV) +/- irinotecan (IRI) are promising in recurrent GBM, the GLARIUS trial explored the efficacy of BEV/IRI as compared to standard TMZ in the first-line therapy of MGMT-non-methylated GBM. METHODS In the randomized, multicenter, open-label GLARIUS trial, adult patients with newly diagnosed, histologically confirmed and MGMT-non-methylated GBM received local radiotherapy (RT, 30 x 2 Gy) and were randomized (2:1) for experimental therapy with BEV (10 mg/kg q2w) during RT followed by maintenance BEV (10 mg/kg q2w) + IRI (125 mg/m² q2w (without enzyme-inducing antiepileptic drugs (EIAEDs)) or 340 mg/m² (with EIAEDs)) or standard therapy with daily TMZ (75 mg/m2) during RT followed by 6 courses of TMZ (150-200 mg/m2/day for 5 days q4w). The primary endpoint was progression-free survival rate after 6 months (PFS-6) as determined by central neuroradiological review. RESULTS The intent-to-treat population included 170 patients (67.1% male, median age 56 years (range 25-78 years), 48.8% complete resection rate, 78.8% of patients with KPS 90% or higher); 116 patients received BEV/IRI, 54 patients had TMZ. The frequencies of adverse events in both arms of the trial were within the expected range. The PFS-6 rate was significantly higher in the BEV/IRI arm (71.1%, 95% CI 58.1-80.8%) than in the TMZ arm (26.2%, 95% CI 13.1-41.4%, p<0.0001 logrank test). CONCLUSIONS The significant and clinically meaningful increase in the primary endpoint PFS-6 upon BEV/IRI chemotherapy suggests that BEV/IRI is superior to standard TMZ therapy in newly diagnosed MGMT-nonmethylated GBM patients. CLINICAL TRIAL INFORMATION 2009-010390-21.