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Neurobiology of Disease Oct 2023G protein-coupled receptor 17 (GPR17) and the WNT pathway are critical players of oligodendrocyte (OL) differentiation acting as essential timers in developing brain to...
G protein-coupled receptor 17 (GPR17) and the WNT pathway are critical players of oligodendrocyte (OL) differentiation acting as essential timers in developing brain to achieve fully-myelinating cells. However, whether and how these two systems are related to each other is still unknown. Of interest, both factors are dysregulated in developing and adult brain diseases, including white matter injury and cancer, making the understanding of their reciprocal interactions of potential importance for identifying new targets and strategies for myelin repair. Here, by a combined pharmacological and biotechnological approach, we examined regulatory mechanisms linking WNT signaling to GPR17 expression in OLs. We first analyzed the relative expression of mRNAs encoding for GPR17 and the T cell factor/Lymphoid enhancer-binding factor-1 (TCF/LEF) transcription factors of the canonical WNT/β-CATENIN pathway, in PDGFRα and O4 OLs during mouse post-natal development. In O4 cells, Gpr17 mRNA level peaked at post-natal day 14 and then decreased concomitantly to the physiological uprise of WNT tone, as shown by increased Lef1 mRNA level. The link between WNT signaling and GPR17 expression was further reinforced in vitro in primary PDGFRα cells and in Oli-neu cells. High WNT tone impaired OL differentiation and drastically reduced GPR17 mRNA and protein levels. In Oli-neu cells, WNT/β-CATENIN activation repressed Gpr17 promoter activity through both putative WNT response elements (WRE) and upregulation of the inhibitor of DNA-binding protein 2 (Id2). We conclude that the WNT pathway influences OL maturation by repressing GPR17, which could have implications in pathologies characterized by dysregulations of the OL lineage including multiple sclerosis and oligodendroglioma.
Topics: Mice; Animals; Wnt Signaling Pathway; beta Catenin; Oligodendrocyte Precursor Cells; Receptor, Platelet-Derived Growth Factor alpha; Nerve Tissue Proteins; Receptors, G-Protein-Coupled; Cell Differentiation; Oligodendroglia; RNA, Messenger
PubMed: 37783234
DOI: 10.1016/j.nbd.2023.106315 -
Clinical & Translational Oncology :... Sep 2023High-grade gliomas (HGG) are the most common primary brain malignancies and account for more than half of all malignant primary brain tumors. The new 2021 WHO...
High-grade gliomas (HGG) are the most common primary brain malignancies and account for more than half of all malignant primary brain tumors. The new 2021 WHO classification divides adult HGG into four subtypes: grade 3 oligodendroglioma (1p/19 codeleted, IDH-mutant); grade 3 IDH-mutant astrocytoma; grade 4 IDH-mutant astrocytoma, and grade 4 IDH wild-type glioblastoma (GB). Radiotherapy (RT) and chemotherapy (CTX) are the current standard of care for patients with newly diagnosed HGG. Several clinically relevant molecular markers that assist in diagnosis and prognosis have recently been identified. The treatment for recurrent high-grade gliomas is not well defined and decision-making is usually based on prior strategies, as well as several clinical and radiological factors. Whereas the prognosis for GB is grim (5-year survival rate of 5-10%) outcomes for the other high-grade gliomas are typically better, depending on the molecular features of the tumor. The presence of neurological deficits and seizures can significantly impact quality of life.
Topics: Adult; Humans; Quality of Life; Neoplasm Recurrence, Local; Glioma; Brain Neoplasms; Glioblastoma; Mutation
PubMed: 37540408
DOI: 10.1007/s12094-023-03245-y -
No Shinkei Geka. Neurological Surgery Sep 2023Oligodendrogliomas were clearly defined as tumors with IDH mutations and 1p/19q codeletion by the World Health Organization(WHO)in 2016. Their prognosis is better than...
Oligodendrogliomas were clearly defined as tumors with IDH mutations and 1p/19q codeletion by the World Health Organization(WHO)in 2016. Their prognosis is better than that of morphologic oligodendrogliomas, which might include some other gliomas according to WHO in 2016 and 2021. The term "low-grade gliomas" does not exist in the WHO classification and has changed in meaning over time; prior to WHO 2016, it meant grade I and II gliomas; subsequently, it changed to "lower-grade gliomas," including grade II and III gliomas, with the same molecular features. In the current classification, IDH wild-type grade II and III gliomas have been eliminated, and "lower-grade gliomas" now only include gliomas with IDH mutations. Maximal safe resection is necessary for a proper molecular diagnosis and survival, and awake craniotomy should be aggressively considered to prevent permanent postoperative neurologic deficits for tumors in the eloquent region. Supramarginal resection is an attractive approach for neurosurgeons to improve survival outcomes, but the evidence is still lacking. Chemoradiotherapy with procarbazine, CCNU, and vincristine is recommended for both grade 2 and 3 oligodendrogliomas. However, the risk of radiation-induced neurotoxicity is a concern in long-term survivors, and several clinical trials have tested the efficacy of chemotherapy alone in terms of cognitive function. Since CCNU is not approved in Japan, ACNU-containing regimen as PAV, or temozolomide are commonly used for the tumor.
Topics: Humans; Oligodendroglioma; Glioma; Cognition; Mutation; Lomustine
PubMed: 37743332
DOI: 10.11477/mf.1436204822 -
Neurobiology of Disease Nov 2023Epilepsy, a common complication of diffuse low-grade gliomas (DLGGs; diffuse oligodendroglioma and astrocytoma collectively), severely compromises the quality of life of...
Epilepsy, a common complication of diffuse low-grade gliomas (DLGGs; diffuse oligodendroglioma and astrocytoma collectively), severely compromises the quality of life of patients. DLGG epileptogenicity may primarily be generated by interactions between the tumor and the neocortex. Neuronal uptake of dysfunctional mitochondria from the extracellular environment can lead to abnormal neuronal discharge. Mitochondrial dysfunction is frequently observed in gliomas that can transmigrate across the plasma membranes. Here, we examined the role of the Rho GTPase-activating protein 44 (RICH2) in mitochondrial dynamics and DLGG-related epilepsy. We investigated the association between mitochondrial and RICH2 expression in human DLGG tissues using immunohistochemistry. We examined the association between RICH2 and epilepsy in nude mouse glioma models by electrophysiology. The effect of RICH2 on mitochondrial morphology and calcium motility were assessed by single cell fluorescence microscopy. Quantitative RT-PCR (qRT-PCR) and Western blot analysis were performed to characterize RICH2 induced expression changes in the genes related to mitochondrial dynamics, mitogenesis and mitochondrial function. We found that RICH2 expression was higher in oligodendroglioma than in astrocytoma and was correlated with better prognosis and higher epilepsy rate in patients. The expression of mitochondria may be associated with clinical DLGG-related epilepsy and reduced by RICH2 overexpression. And RICH2 could promote DLGG-related epilepsy in tumorigenic nude mice. RICH2 overexpression decreased calcium flow and the mitochondria released from glioma cells (SW1088 and U251) into the extracellular environment, potentially via downregulation of MFN-1/MFN-2 levels which suggests reduced mitochondrial fusion. In addition, we observed decreased mitochondrial trafficking into neurons (released from glioma cells and trafficked into neurons), which could explain the higher incidence of DLGG-related epilepsy due to reduced neuroprotection. Furthermore, RICH2 downregulated MAPK/ERK/HIF-1 pathway. In conclusion, these results suggest that RICH2 could promote epilepsy by (i) inhibiting mitochondrial fusion via MFN downregulation and Drp-1 upregulation; (ii) altering the MAPK/ERK/Hif-1 signaling axis. RICH2 may be a potential target in the treatment of DLGG-related epilepsy.
Topics: Animals; Mice; Humans; Oligodendroglioma; Calcium; Mice, Nude; Quality of Life; Glioma; Mitochondria; Astrocytoma
PubMed: 37926169
DOI: 10.1016/j.nbd.2023.106344 -
Nature Reviews. Neurology May 2024Gliomas are the most common malignant primary brain tumours in adults and cannot usually be cured with standard cancer treatments. Gliomas show intratumoural and... (Review)
Review
Gliomas are the most common malignant primary brain tumours in adults and cannot usually be cured with standard cancer treatments. Gliomas show intratumoural and intertumoural heterogeneity at the histological and molecular levels, and they frequently contain mutations in the isocitrate dehydrogenase 1 (IDH1) or IDH2 gene. IDH-mutant adult-type diffuse gliomas are subdivided into grade 2, 3 or 4 IDH-mutant astrocytomas and grade 2 or 3 IDH-mutant, 1p19q-codeleted oligodendrogliomas. The product of the mutated IDH genes, D-2-hydroxyglutarate (D-2-HG), induces global DNA hypermethylation and interferes with immunity, leading to stimulation of tumour growth. Selective inhibitors of mutant IDH, such as ivosidenib and vorasidenib, have been shown to reduce D-2-HG levels and induce cellular differentiation in preclinical models and to induce MRI-detectable responses in early clinical trials. The phase III INDIGO trial has demonstrated superiority of vorasidenib, a brain-penetrant pan-mutant IDH inhibitor, over placebo in people with non-enhancing grade 2 IDH-mutant gliomas following surgery. In this Review, we describe the pathway of development of IDH inhibitors in IDH-mutant low-grade gliomas from preclinical models to clinical trials. We discuss the practice-changing implications of the INDIGO trial and consider new avenues of investigation in the field of IDH-mutant gliomas.
PubMed: 38760442
DOI: 10.1038/s41582-024-00967-7 -
Neuro-oncology Practice Oct 2023No consensus germline testing guidelines currently exist for glioma patients, so the prevalence of germline pathogenic variants remains unknown. This study aims to...
BACKGROUND
No consensus germline testing guidelines currently exist for glioma patients, so the prevalence of germline pathogenic variants remains unknown. This study aims to determine the prevalence and type of pathogenic germline variants in adult glioma.
METHODS
A retrospective review at a single institution with paired tumor/normal sequencing from August 2018-April 2022 was performed and corresponding clinical data were collected.
RESULTS
We identified 152 glioma patients of which 15 (9.8%) had pathogenic germline variants. Pathogenic germline variants were seen in 11/84 (13.1%) of Glioblastoma, wild type; 3/42 (7.1%) of Astrocytoma, mutant; and 1/26 (3.8%) of Oligodendroglioma, mutant, and 1p/19q co-deleted patients. Pathogenic variants in , and were most common (3/15, 20% each). variants occurred in 2/15 (13%) patients, with variants in , , , and occurring in one patient (7%) each. Prior cancer diagnosis was found in 5/15 patients (33%). Second-hit somatic variants were seen in 3/15 patients (20%) in , and . Referral to genetics was performed in 6/15 (40%) patients with pathogenic germline variants. 14/15 (93%) of patients discovered their pathogenic variant as a result of their paired glioma sequencing.
CONCLUSIONS
These findings suggest a possible overlooked opportunity for determination of hereditary cancer syndromes with impact on surveillance as well as potential broader treatment options. Further studies that can determine the role of variants in gliomagenesis and confirm the occurrence and types of pathogenic germline variants in patients with wild type compared to mutant tumors are necessary.
PubMed: 37720399
DOI: 10.1093/nop/npad033 -
MGMT Promoter Methylation Predicts Overall Survival after Chemotherapy for 1p/19q-Codeleted Gliomas.Clinical Cancer Research : An Official... Nov 2023While MGMT promoter methylation (mMGMT) is predictive of response to alkylating chemotherapy and guides treatment decisions in glioblastoma, its role in grade 2 and 3...
PURPOSE
While MGMT promoter methylation (mMGMT) is predictive of response to alkylating chemotherapy and guides treatment decisions in glioblastoma, its role in grade 2 and 3 glioma remains unclear. Recent data suggest that mMGMT is prognostic of progression-free survival in 1p/19q-codeleted oligodendrogliomas, but an effect on overall survival (OS) has not been demonstrated.
EXPERIMENTAL DESIGN
We identified patients with newly diagnosed 1p/19q-codeleted gliomas and known MGMT promoter status in the National Cancer Database from 2010 to 2019. Multivariable Cox proportional hazards regression modeling was used to assess the effect of mMGMT on OS after adjusting for age, sex, race, comorbidity, grade, extent of resection, chemotherapy, and radiotherapy.
RESULTS
We identified 1,297 eligible patients, 938 (72.3%) of whom received chemotherapy in their initial course of treatment. The MGMT promoter was methylated in 1,009 (77.8%) patients. Unmethylated MGMT (uMGMT) was associated with worse survival compared with mMGMT [70% {95% confidence interval (CI), 64%-77%} vs. 81% (95% CI, 78%-85%); P < 0.001; adjusted HR (aHR), 2.35 (95% CI, 1.77-3.14)]. uMGMT was associated with worse survival in patients who received chemotherapy [63% (95% CI, 55-73%) vs. 80% (95% CI, 76%-84%); P < 0.001; aHR, 2.61 (95% CI, 1.89-3.60)] but not in patients who did not receive chemotherapy [P = 0.38; HR, 1.31 (95% CI, 0.71-2.42)]. Similar results were observed regardless of World Health Organization grade and after single- or multiagent chemotherapy.
CONCLUSIONS
Our study demonstrates an association between mMGMT and OS in 1p/19q-codeleted gliomas. MGMT promoter status should be considered as a stratification factor in future clinical trials of 1p/19q-codeleted gliomas that use OS as an endpoint.
Topics: Humans; Brain Neoplasms; Methylation; Glioma; Prognosis; Glioblastoma; DNA Methylation; Isocitrate Dehydrogenase; DNA Repair Enzymes; DNA Modification Methylases; Tumor Suppressor Proteins
PubMed: 37611077
DOI: 10.1158/1078-0432.CCR-23-1295 -
Cancer Dec 2023Few large studies have investigated quality of life (QOL) for adults diagnosed with lower grade glioma (LGG).
BACKGROUND
Few large studies have investigated quality of life (QOL) for adults diagnosed with lower grade glioma (LGG).
METHODS
QOL was assessed for 320 adults with LGG (World Health Organization grade 2/3) enrolled in the International Low Grade Glioma Registry by using the Medical Outcomes Study 36-Item Short Form health survey. Data on symptoms were also collected. QOL outcomes were examined by treatment group and also compared to those from a population-based case-control study of meningioma (the Meningioma Consortium), in which 1722 meningioma cases diagnosed among residents of Connecticut, Massachusetts, California, Texas, and North Carolina from May 1, 2006 through March 14, 2013 were enrolled and frequency matched to 1622 controls by age, sex, and geography.
RESULTS
The LGG sample average age is 45 years at the time of interview and 53.1% male. Almost 55% of patients had received radiation and chemotherapy (primarily temozolomide); 32.4% had received neither treatment. Two-thirds of participants with LGG report difficulty with speaking, memory, or thinking, and over one of three reports personality change or difficulty driving. After controlling for age and other comorbidities, individuals with LGG report levels of physical, emotional, and mental health functioning below those reported in a meningioma as well as a general healthy population.
CONCLUSIONS
Despite being relatively young, persons with LGG report significantly reduced QOL compared to persons with nonmalignant brain tumors and to a control population, which highlights the need to better acknowledge and manage these symptoms for this group of patients diagnosed in the prime of life.
Topics: Adult; Humans; Male; Middle Aged; Female; Quality of Life; Meningioma; Case-Control Studies; Glioma; Brain Neoplasms; Meningeal Neoplasms
PubMed: 37599093
DOI: 10.1002/cncr.34980 -
Journal of Neuro-oncology Aug 2023Since the introduction of the molecular definition of oligodendrogliomas based on isocitrate dehydrogenase (IDH)-status and the 1p19q-codeletion, it has become...
PURPOSE
Since the introduction of the molecular definition of oligodendrogliomas based on isocitrate dehydrogenase (IDH)-status and the 1p19q-codeletion, it has become increasingly evident how this glioma entity differs much from other diffuse lower grade gliomas and stands out with longer survival and often better responsiveness to adjuvant therapy. Therefore, apart from using a molecular oligodendroglioma definition, an extended follow-up time is necessary to understand the nature of this slow growing, yet malignant condition. The aim of this study was to describe the long-term course of the oligodendroglioma disease in a population-based setting and to determine which factors affect outcome in terms of survival.
METHODS
All adults with WHO-grade 2 oligodendrogliomas with known 1p19q-codeletion from five Scandinavian neurosurgical centers and with a follow-up time exceeding 5 years, were analyzed regarding survival and factors potentially affecting survival.
RESULTS
126 patients diagnosed between 1998 and 2016 were identified. The median follow-up was 12.0 years, and the median survival was 17.8 years (95% CI 16.0-19.6). Factors associated with shorter survival in multivariable analysis were age (HR 1.05 per year; CI 1.02-1.08, p < 0.001), tumor diameter (HR 1.05 per millimeter; CI 1.02-1.08, p < 0.001) and poor preoperative functional status (KPS < 80) (HR 4.47; CI 1.70-11.78, p = 0.002). In our material, surgical strategy was not associated with survival.
CONCLUSION
Individuals with molecularly defined oligodendrogliomas demonstrate long survival, also in a population-based setting. This is important to consider for optimal timing of therapies that may cause long-term side effects. Advanced age, large tumors and poor function before surgery are predictors of shorter survival.
Topics: Adult; Humans; Oligodendroglioma; Follow-Up Studies; Glioma; Combined Modality Therapy; World Health Organization
PubMed: 37603235
DOI: 10.1007/s11060-023-04368-6 -
International Journal of Molecular... Oct 2023The median survival time has been reported to vary between 5 and 8 years in low-grade (WHO grade 2) astrocytoma, and between 10 and 15 years for grade 2...
The median survival time has been reported to vary between 5 and 8 years in low-grade (WHO grade 2) astrocytoma, and between 10 and 15 years for grade 2 oligodendroglioma. Targeted alpha therapy (TAT), using the modified peptide vector [Bi]Bi/[Ac]Ac-DOTA-substance P, has been developed to treat glioblastoma (GBM), a prevalent malignant brain tumor. In order to assess the risk of late neurotoxicity, assuming that reduced tumor cell proliferation and invasion should directly translate into good responses in low-grade gliomas (LGGs), a limited number of patients with diffuse invasive astrocytoma (n = 8) and oligodendroglioma (n = 3) were offered TAT. In two oligodendroglioma patients, TAT was applied as a second-line treatment for tumor progression, 10 years after targeted beta therapy using [Y]Y-DOTA-substance P. The radiopharmaceutical was locally injected directly into the tumor via a stereotactic insertion of a capsule-catheter system. The activity used for radiolabeling was 2-2.5 GBq of Bismuth-213 and 17 to 35 MBq of Actinium-225, mostly applied in a single fraction. The recurrence-free survival times were in the range of 2 to 16 years (median 11 years) in low-grade astrocytoma (n = 8), in which TAT was administered following a biopsy or tumor debulking. Regarding oligodendroglioma, the recurrence-free survival time was 24 years in the first case treated, and 4 and 5 years in the two second-line cases. In conclusion, TAT leads to long-term tumor control in the majority of patients with LGG, and recurrence has so far not manifested in patients with low-grade (grade 2) astrocytomas who received TAT as a first-line therapy. We conclude that targeted alpha therapy has the potential to become a new treatment paradigm in LGG.
Topics: Humans; Oligodendroglioma; Substance P; Glioma; Astrocytoma; Glioblastoma; Brain Neoplasms
PubMed: 37958683
DOI: 10.3390/ijms242115701