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149 result(s) for "Idbaih, Ahmed"
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Recurrent Glioblastoma: From Molecular Landscape to New Treatment Perspectives
Glioblastoma is the most frequent and aggressive form among malignant central nervous system primary tumors in adults. Standard treatment for newly diagnosed glioblastoma consists in maximal safe resection, if feasible, followed by radiochemotherapy and adjuvant chemotherapy with temozolomide; despite this multimodal treatment, virtually all glioblastomas relapse. Once tumors progress after first-line therapy, treatment options are limited and management of recurrent glioblastoma remains challenging. Loco-regional therapy with re-surgery or re-irradiation may be evaluated in selected cases, while traditional systemic therapy with nitrosoureas and temozolomide rechallenge showed limited efficacy. In recent years, new clinical trials using, for example, regorafenib or a combination of tyrosine kinase inhibitors and immunotherapy were performed with promising results. In particular, molecular targeted therapy could show efficacy in selected patients with specific gene mutations. Nonetheless, some molecular characteristics and genetic alterations could change during tumor progression, thus affecting the efficacy of precision medicine. We therefore reviewed the molecular and genomic landscape of recurrent glioblastoma, the strategy for clinical management and the major phase I-III clinical trials analyzing recent drugs and combination regimens in these patients.
Histiocytoses: emerging neoplasia behind inflammation
Histiocytoses are disorders characterised by inflammation and the accumulation of cells derived from the monocyte and macrophage lineages, which results in tissue damage. Although they are often considered rare disorders with protean clinical manifestations, considerable advances in the understanding of their genetics have led to increased clinical recognition of these conditions, and fuelled further insights into their pathogenesis. In this Review, we describe insights into the cells of origin, molecular pathology, clinical features, and treatment strategies for some of the most common histiocytic disorders, including Langerhans cell histiocytosis, Erdheim-Chester disease, and Rosai-Dorfman disease. With the discovery of recurrent mutations affecting the mitogen-activated protein kinase and mTOR–AKT pathways in some of these histiocytoses, our understanding of these diseases has now evolved from the concept of a primary inflammatory condition to that of a clonal neoplastic disease. This understanding has led to the development of effective mechanism-based therapeutic strategies for patients with histiocytic diseases.
Lomustine and Bevacizumab in Progressive Glioblastoma
Bevacizumab is approved for the treatment of patients with progressive glioblastoma on the basis of uncontrolled data. Data from a phase 2 trial suggested that the addition of bevacizumab to lomustine might improve overall survival as compared with monotherapies. We sought to determine whether the combination would result in longer overall survival than lomustine alone among patients at first progression of glioblastoma. We randomly assigned patients with progression after chemoradiation in a 2:1 ratio to receive lomustine plus bevacizumab (combination group, 288 patients) or lomustine alone (monotherapy group, 149 patients). The methylation status of the promoter of O -methylguanine-DNA methyltransferase (MGMT) was assessed. Health-related quality of life and neurocognitive function were evaluated at baseline and every 12 weeks. The primary end point of the trial was overall survival. A total of 437 patients underwent randomization. The median number of 6-week treatment cycles was three in the combination group and one in the monotherapy group. With 329 overall survival events (75.3%), the combination therapy did not provide a survival advantage; the median overall survival was 9.1 months (95% confidence interval [CI], 8.1 to 10.1) in the combination group and 8.6 months (95% CI, 7.6 to 10.4) in the monotherapy group (hazard ratio for death, 0.95; 95% CI, 0.74 to 1.21; P=0.65). Locally assessed progression-free survival was 2.7 months longer in the combination group than in the monotherapy group: 4.2 months versus 1.5 months (hazard ratio for disease progression or death, 0.49; 95% CI, 0.39 to 0.61; P<0.001). Grade 3 to 5 adverse events occurred in 63.6% of the patients in the combination group and 38.1% of the patients in the monotherapy group. The addition of bevacizumab to lomustine affected neither health-related quality of life nor neurocognitive function. The MGMT status was prognostic. Despite somewhat prolonged progression-free survival, treatment with lomustine plus bevacizumab did not confer a survival advantage over treatment with lomustine alone in patients with progressive glioblastoma. (Funded by an unrestricted educational grant from F. Hoffmann-La Roche and by the EORTC Cancer Research Fund; EORTC 26101 ClinicalTrials.gov number, NCT01290939 ; Eudra-CT number, 2010-023218-30 .).
Primary brain tumours in adults
Important advances have been made in the understanding and management of adult gliomas and primary CNS lymphomas—the two most common primary brain tumours. Progress in imaging has led to a better analysis of the nature and grade of these tumours. Findings from large phase 3 studies have yielded some standard treatments for gliomas, and have confirmed the prognostic value of specific molecular alterations. High-throughput methods that enable genome-wide analysis of tumours have improved the knowledge of tumour biology, which should lead to a better classification of gliomas and pave the way for so-called targeted therapy trials. Primary CNS lymphomas are a group of rare non-Hodgkin lymphomas. High-dose methotrexate-based regimens increase survival, but the standards of care and the place of whole-brain radiotherapy remain unclear, and are likely to depend on the age of the patient. The focus now is on the development of new polychemotherapy regimens to reduce or defer whole-brain radiotherapy and its delayed complications.
Same-day genomic and epigenomic diagnosis of brain tumors using real-time nanopore sequencing
Molecular classification of cancer has entered clinical routine to inform diagnosis, prognosis, and treatment decisions. At the same time, new tumor entities have been identified that cannot be defined histologically. For central nervous system tumors, the current World Health Organization classification explicitly demands molecular testing, e.g., for 1p/19q-codeletion or IDH mutations, to make an integrated histomolecular diagnosis. However, a plethora of sophisticated technologies is currently needed to assess different genomic and epigenomic alterations and turnaround times are in the range of weeks, which makes standardized and widespread implementation difficult and hinders timely decision making. Here, we explored the potential of a pocket-size nanopore sequencing device for multimodal and rapid molecular diagnostics of cancer. Low-pass whole genome sequencing was used to simultaneously generate copy number (CN) and methylation profiles from native tumor DNA in the same sequencing run. Single nucleotide variants in IDH1 , IDH2 , TP53 , H3F3A, and the TERT promoter region were identified using deep amplicon sequencing. Nanopore sequencing yielded ~0.1X genome coverage within 6 h and resulting CN and epigenetic profiles correlated well with matched microarray data. Diagnostically relevant alterations, such as 1p/19q codeletion, and focal amplifications could be recapitulated. Using ad hoc random forests, we could perform supervised pan-cancer classification to distinguish gliomas, medulloblastomas, and brain metastases of different primary sites. Single nucleotide variants in IDH1 , IDH2, and H3F3A were identified using deep amplicon sequencing within minutes of sequencing. Detection of TP53 and TERT promoter mutations shows that sequencing of entire genes and GC-rich regions is feasible. Nanopore sequencing allows same-day detection of structural variants, point mutations, and methylation profiling using a single device with negligible capital cost. It outperforms hybridization-based and current sequencing technologies with respect to time to diagnosis and required laboratory equipment and expertise, aiming to make precision medicine possible for every cancer patient, even in resource-restricted settings.
Repeated blood–brain barrier opening with a nine-emitter implantable ultrasound device in combination with carboplatin in recurrent glioblastoma: a phase I/II clinical trial
Here, the results of a phase 1/2 single-arm trial (NCT03744026) assessing the safety and efficacy of blood-brain barrier (BBB) disruption with an implantable ultrasound system in recurrent glioblastoma patients receiving carboplatin are reported. A nine-emitter ultrasound implant was placed at the end of tumor resection replacing the bone flap. After surgery, activation to disrupt the BBB was performed every four weeks either before or after carboplatin infusion. The primary objective of the Phase 1 was to evaluate the safety of escalating numbers of ultrasound emitters using a standard 3 + 3 dose escalation. The primary objective of the Phase 2 was to evaluate the efficacy of BBB opening using magnetic resonance imaging (MRI). The secondary objectives included safety and clinical efficacy. Thirty-three patients received a total of 90 monthly sonications with carboplatin administration and up to nine emitters activated without observed DLT. Grade 3 procedure-related adverse events consisted of pre syncope ( n  = 3), fatigue ( n  = 1), wound infection ( n  = 2), and pain at time of device connection ( n  = 7). BBB opening endpoint was met with 90% of emitters showing BBB disruption on MRI after sonication. In the 12 patients who received carboplatin just prior to sonication, the progression-free survival was 3.1 months, the 1-year overall survival rate was 58% and median overall survival was 14.0 months from surgery. Recent work indicates that drug delivery to the brain can be improved through disruption of the blood brain barrier using low intensity pulsed ultrasound. Here, the authors report a phase I/II clinical trial investigating the combination of a nine-emitter implantable ultrasound device and carboplatin in patients with recurrent glioblastoma.
Cumulative incidence and risk factors for radiation induced leukoencephalopathy in high grade glioma long term survivors
The incidence and risk factors associated with radiation-induced leukoencephalopathy (RIL) in long-term survivors of high-grade glioma (HGG) are still poorly investigated. We performed a retrospective research in our institutional database for patients with supratentorial HGG treated with focal radiotherapy, having a progression-free overall survival > 30 months and available germline DNA. We reviewed MRI scans for signs of leukoencephalopathy on T2/FLAIR sequences, and medical records for information on cerebrovascular risk factors and neurological symptoms. We investigated a panel of candidate single nucleotide polymorphisms (SNPs) to assess genetic risk. Eighty-one HGG patients (18 grade IV and 63 grade III, 50M/31F) were included in the study. The median age at the time of radiotherapy was 48 years old (range 18–69). The median follow-up after the completion of radiotherapy was 79 months. A total of 44 patients (44/81, 54.3%) developed RIL during follow-up. Twenty-nine of the 44 patients developed consistent symptoms such as subcortical dementia (n = 28), gait disturbances (n = 12), and urinary incontinence (n = 9). The cumulative incidence of RIL was 21% at 12 months, 42% at 36 months, and 48% at 60 months. Age > 60 years, smoking, and the germline SNP rs2120825 (PPARg locus) were associated with an increased risk of RIL. Our study identified potential risk factors for the development of RIL (age, smoking, and the germline SNP rs2120825) and established the rationale for testing PPARg agonists in the prevention and management of late-delayed radiation-induced neurotoxicity.
Marizomib sensitizes primary glioma cells to apoptosis induced by a latest-generation TRAIL receptor agonist
Due to the absence of curative treatments for glioblastoma (GBM), we assessed the efficacy of single and combination treatments with a translationally relevant 2nd generation TRAIL-receptor agonist (IZI1551) and the blood–brain barrier (BBB) permeant proteasome inhibitor marizomib in a panel of patient-derived glioblastoma cell lines. These cells were cultured using protocols that maintain the characteristics of primary tumor cells. IZI1551+marizomib combination treatments synergistically induced apoptotic cell death in the majority of cases, both in 2D, as well as in 3D spheroid cultures. In contrast, single-drug treatments largely failed to induce noticeable amounts of cell death. Kinetic analyses suggested that time-shifted drug exposure might further increase responsiveness, with marizomib pre-treatments indeed strongly enhancing cell death. Cell death responses upon the addition of IZI1551 could also be observed in GBM cells that were kept in a medium collected from the basolateral side of a human hCMEC/D3 BBB model that had been exposed to marizomib. Interestingly, the subset of GBM cell lines resistant to IZI1551+marizomib treatments expressed lower surface amounts of TRAIL death receptors, substantially lower amounts of procaspase-8, and increased amounts of cFLIP, suggesting that apoptosis initiation was likely too weak to initiate downstream apoptosis execution. Indeed, experiments in which the mitochondrial apoptosis threshold was lowered by antagonizing Mcl-1 re-established sensitivity to IZI1551+marizomib in otherwise resistant cells. Overall, our study demonstrates a high efficacy of combination treatments with a latest-generation TRAIL receptor agonist and the BBB permeant proteasome inhibitor marizomib in relevant GBM cell models, as well as strategies to further enhance responsiveness and to sensitize subgroups of otherwise resistant GBM cases.
Temporary blood–brain barrier disruption by low intensity pulsed ultrasound increases carboplatin delivery and efficacy in preclinical models of glioblastoma
Introduction Glioblastoma (GBM) is the most common and aggressive primary brain cancer in adults. Few cytotoxic chemotherapies have been shown to be effective against GBM, due in part to the presence of the blood–brain barrier (BBB), which reduces the penetration of chemotherapies from the blood to the brain. Ultrasound-induced BBB opening (US-BBB) has been shown to increase the penetration of multiple chemotherapeutic agents in the brain in animal models. In the current study, the anti-tumor activity of carboplatin chemotherapy with and without US-BBB was investigated in several GBM mouse models. Methods First, the IC50 of two commercial (U87 and U251) and six patient-derived GBM cell lines (PDCL) to carboplatin was measured. Next, U87 was subcutaneously grafted to a nude mouse model to test the in vivo response of the tumor to carboplatin in the absence of the BBB. Lastly, nude mice bearing orthotopically xenografted GBM cell lines (U87 or a PDCL) were randomized to four experimental groups: (i) untreated, (ii) US-BBB alone, (iii) carboplatin alone and, (iv) carboplatin + US-BBB. Mice were treated once weekly for 4 weeks and monitored for toxicity, tumor growth, and survival. Results Carboplatin plus US-BBB enhanced survival (p = 0.03) and delayed tumor growth (p < 0.05) of GBM-bearing mice compared to carboplatin alone, with a 4.2-fold increase of carboplatin penetration in the brain, without evidence of significant neurological or systemic toxicity. Conclusions Carboplatin efficacy was enhanced in GBM mouse models with US-BBB and appears to be a promising chemotherapy for this approach.
Bevacizumab and temozolomide in patients with first recurrence of WHO grade II and III glioma, without 1p/19q co-deletion (TAVAREC): a randomised controlled phase 2 EORTC trial
Bevacizumab is frequently used in the treatment of recurrent WHO grade II and III glioma, but without supporting evidence from randomised trials. Therefore, we assessed the use of bevacizumab in patients with first recurrence of grade II or III glioma who did not have 1p/19q co-deletion. The TAVAREC trial was a randomised, open-label phase 2 trial done at 32 centres across Europe in patients with locally diagnosed grade II or III glioma without 1p/19q co-deletion, with a first and contrast-enhancing recurrence after initial radiotherapy or chemotherapy, or both. Previous chemotherapy must have been stopped at least 6 months before enrolment and radiotherapy must have been stopped at least 3 months before enrolment. Random group assignment was done electronically through the European Organisation for Research and Treatment of Cancer web-based system, stratified by a minimisation procedure using institution, initial histology (WHO grade II vs III), WHO performance status (0 or 1 vs 2), and previous treatment (radiotherapy, chemotherapy, or both). Patients were assigned to receive either temozolomide (150–200 mg/m2, orally) monotherapy on days 1–5 every 4 weeks for a maximum of 12 cycles, or the same temozolomide regimen in combination with bevacizumab (10 mg/kg, intravenously) every 2 weeks until progression. The primary endpoint was overall survival at 12 months in the per-protocol population. Safety analyses were done in all patients who started their allocated treatment. The study is registered at EudraCT (2009–017422–39) and ClinicalTrials.gov (NCT01164189), and is complete. Between Feb 8, 2011, and July 31, 2015, 155 patients were enrolled and randomly assigned to receive either monotherapy (n=77) or combination therapy (n=78). Overall survival in the per-protocol population at 12 months was achieved by 44 (61% [80% CI 53–69]) of 72 patients in the temozolomide group and 38 (55% [47–69]) of 69 in the combination group. The most frequent toxicity was haematological: 17 (23%) of 75 patients in the monotherapy group and 25 (33%) of 76 in the combination group developed grade 3 or 4 haematological toxicity. Other than haematological toxicities, the most common adverse events were nervous system disorders (59 [79%] of 75 patients in the monotherapy group vs 65 [86%] of 76 in the combination group), fatigue (53 [70%] vs 61 [80%]), and nausea (39 [52%] vs 43 [56%]). Infections were more frequently reported in the combination group (29 [38%] of 76 patients) than in the monotherapy group (17 [23%] of 75). One treatment-related death was reported in the combination group (infection after intratumoral haemorrhage during a treatment-related grade 4 thrombocytopenia). We found no evidence of improved overall survival with bevacizumab and temozolomide combination treatment versus temozolomide monotherapy. The findings from this study provide no support for further phase 3 studies on the role of bevacizumab in this disease. Roche Pharmaceuticals.