Moyamoya disease-specific extracellular vesicle-derived microRNAs in the cerebrospinal fluid revealed by comprehensive expression analysis through microRNA sequencing.

PURPOSE: To examine the specific changes that occur in the expression levels of extracellular vesicle-derived microRNAs (miRNAs) in intracranial cerebrospinal fluid (CSF) in moyamoya disease. METHODS: Patients with arteriosclerotic cerebral ischemia were used as controls to eliminate the effects of cerebral ischemia. Intracranial CSF was collected from moyamoya disease and control patients during bypass surgery. Extracellular vesicles (EVs) were extracted from the CSF. Comprehensive expression analysis of miRNAs extracted from EVs by next-generation sequencing (NGS) and validation by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed. RESULTS: Experiments were conducted on eight cases of moyamoya disease and four control cases. In the comprehensive miRNA expression analysis, 153 miRNAs were upregulated, and 98 miRNAs were downregulated in moyamoya disease compared to the control cases (q-value < 0.05 and |log2 fold change|> 1). qRT-PCR performed on the four most variable miRNAs (hsa-miR-421, hsa-miR-361-5p, hsa-miR-320a, and hsa-miR-29b-3p) associated with vascular lesions among the differentially expressed miRNAs gave the same results as miRNA sequencing. On gene ontology (GO) analysis for the target genes, cytoplasmic stress granule was the most significant GO term. CONCLUSIONS: This study is the first comprehensive expression analysis of EV-derived miRNAs in the CSF of moyamoya disease patients using NGS. The miRNAs identified here may be related to the etiology and pathophysiology of moyamoya disease.

Functional connector hubs in the cerebellum.

Accumulating evidence from anatomical and neuroimaging studies suggests that the cerebellum is engaged in a variety of motor and cognitive tasks. Given its various functions, a key question is whether the cerebellum also plays an important role in the brain's integrative functions. Here, we hypothesize the existence of connector regions, also known as connector hubs, where multiple resting state networks converged in the cerebellum. To verify this, we employed a recently developed voxel-level network measure called functional connectivity overlap ratio (FCOR), which could be used to quantify the spatial extent of a region's connection to several large-scale cortical networks. Using resting state functional MRI data from 101 healthy participants, cerebellar FCOR maps were constructed and used to identify the locations of connector hubs in the cerebellum. Results showed that a number of cerebellar regions exhibited strong connectivity with multiple functional networks, verifying our hypothesis. These highly connected regions were located in the posterior cerebellum, especially in lobules VI, VII, and IX, and mainly connected to the core neurocognitive networks such as default mode and executive control networks. Regions associated with the sensorimotor network were also localized in lobule V, VI, and VIII, albeit in small clusters. These cerebellar connector hubs may play an essential role in the processing of information across the core neurocognitive networks.

Lack of GD3 synthase (St8sia1) attenuates malignant properties of gliomas in genetically engineered mouse model.

High expression of gangliosides GD3 and GD2 is observed in human gliomas. The functions of GD3 and GD2 in malignant properties have been reported in glioma cells in vitro, but those functions have not yet been investigated in vivo. In this study, we showed that deficiency of GD3 synthase (GD3S, St8sia1) attenuated glioma progression and clinical and pathological features in a platelet-derived growth factor B-driven murine glioma model. Lack of GD3S resulted in the prolonged lifespan of glioma-bearing mice and low-grade pathology in generated gliomas. Correspondingly, they showed reduced phosphorylation levels of Akt, Erks, and Src family kinases in glioma tissues. A DNA microarray study revealed marked alteration in the expression of various genes, particularly in MMP family genes, in GD3S-deficient gliomas. Re-expression of GD3S restored expression of MMP9 in primary-cultured glioma cells. We also identified a transcription factor, Ap2α, expressed in parallel with GD3S expression, and showed that Ap2α was critical for the induction of MMP9 by transfection of its cDNA and luciferase reporter genes, and a ChIP assay. These findings suggest that GD3S enhances the progression of gliomas by enhancement of the Ap2α-MMP9 axis. This is the first report to describe the tumor-enhancing functions of GD3S in vivo.

Impact of the extent of resection on the survival of patients with grade II and III gliomas using awake brain mapping.

PURPOSE: The aim of this study was to assess the effect of the extent of resection (EOR) of tumors on survival in a series of patients with grade II and III gliomas (GII/III-gliomas) who underwent awake brain mapping. METHODS: We retrospectively analyzed 126 patients with GII/III-gliomas in the dominant and non-dominant hemisphere who underwent awake brain surgery at the same institution between December 2012 and May 2020. RESULTS: EOR cut-off values for improved progression-free survival (PFS) were determined by a receiver operator characteristic (ROC) analysis of 5-year PFS. The ROC for EOR showed a cut-off value of ≥ 85.3%. The median PFS rate of patients with GII/III-gliomas in the group with an EOR ≥ 100%, including supratotal resection (n = 47; median survival [MS], not reached), was significantly higher than that in the group with an EOR < 90% (n = 52; MS, 43.1 months; 95% CI 37.7-48.5 months; p = 0.03). In patients with diffuse astrocytomas and anaplastic astrocytomas, the group with EOR ≥ 100%, including supratotal resection (n = 25; MS, not reached), demonstrated a significantly better PFS rate than did the group with an EOR < 100% (n = 45; MS, 35.8 months; 95% CI 19.9-51.6 months; p = 0.03). Supratotal or gross total resection was correlated with better PFS in IDH-mutant type of diffuse astrocytomas and anaplastic astrocytomas (n = 19; MS, not reached vs. n = 35; MS, 40.6 months; 95% CI 22.3-59.0 months; p = 0.02). By contrast, supratotal or gross total resection was not associated with longer PFS rates in patients with IDH-wild type of diffuse astrocytomas and anaplastic astrocytomas. CONCLUSIONS: The present study demonstrates a significant association between tumor EOR and survival in patients with GII/III gliomas. The EOR cut-off value for 5-year PFS was ≥ 85.3%. It is noteworthy that supratotal or gross total resection significantly correlated with better PFS in IDH-mutant type of WHO grade II and III astrocytic tumors. In light of our finding that EOR did not correlate with PFS in patients with aggressive IDH-wild type of diffuse astrocytomas and anaplastic astrocytomas, we suggest treatments that are more intensive will be needed for the control of these tumors.

Efficacy and safety of nivolumab in Japanese patients with first recurrence of glioblastoma: an open-label, non-comparative study.

BACKGROUND: An open-label, non-comparative study assessed the efficacy and safety of nivolumab in Japanese patients with first recurrence glioblastoma. METHODS: Patients with first recurrence of histologically confirmed World Health Organization Grade IV glioma, after treatment with temozolomide and radiotherapy, received nivolumab 3 mg/kg every 2 weeks until confirmed disease progression (Response Assessment in Neuro-Oncology criteria) or toxicity. Primary endpoint was 1-year overall survival rate assessed by Bayesian approach. The prespecified efficacy criterion was that the Bayesian posterior probability threshold for exceeding the 1-year overall survival of bevacizumab (34.5%) from the Japanese phase 2 study (JO22506) would be 93%. RESULTS: Of the 50 enrolled patients, 44 (88.0%) had recurrent malignant glioma (glioblastoma, gliosarcoma), and of these, 26 (59.1%) had at least one measurable lesion at baseline. The Bayesian posterior mean 1-year overall survival (90% Bayesian credible intervals) with nivolumab was 54.4% (42.27-66.21), and the Bayesian posterior probability of exceeding the threshold of the 1-year overall survival rate of bevacizumab (34.5%) was 99.7%. Median (90% confidence interval) overall and progression-free survival was 13.1 (10.4-17.7) and 1.5 (1.4-1.5) months, respectively. One partial response was observed (objective response rate 1/26 evaluable patients [3.8%]). Treatment-related adverse event rates were 14.0% for Grade 3-4 and 2.0% for Grade 5; most adverse events resolved and were manageable. CONCLUSIONS: The 1-year overall survival with nivolumab monotherapy in Japanese patients with glioblastoma met the prespecified efficacy criterion. The safety profile of nivolumab was consistent with that observed in other tumor types. CLINICAL TRIAL REGISTRATION: JapicCTI-152967.

Expression of programmed cell death ligand-1 by immune cells in the microenvironment is a favorable prognostic factor for primary diffuse large B-cell lymphoma of the central nervous system.

Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (PCNS-DLBCL) is rare. Thirty-nine patients consecutively diagnosed as having PCNS-DLBCL were analyzed to highlight the prognostic value of the expression of programmed cell death ligand-1 (PD-L1) by neoplastic cells and immune cells in the microenvironment. They were positive for CD20 in all (100%), CD5 in two (5%), CD10 in nine (23%), BCL-2 in 27 (69%), BCL-6 in 34 (87%), and MUM-1 in 37 (95%). Only one case was positive for neoplastic PD-L1, with an unexpectedly long clinical course of 92 months. The remaining 38 cases were further divided into three groups based on the percentage of PD-L1+ cells among microenvironmental immune cells. Cutoffs of < 5%, 5-40%, and ≥ 40% successfully stratified mean prognoses with three-year overall survival (OS) of 21%, 63%, and 100% (P = 0.009), respectively. Progression-free survival (PFS) and OS were different between the groups with and without methotrexate (MTX)-containing chemotherapy (P = 0.007 and P < 0.001, respectively). Multivariate analysis identified three independent adverse factors of OS: PD-L1 negativity (< 5%) on microenvironmental immune cells (P = 0.027), deep structure involvement (P = 0.034), and performance status (PS) 2-4 (P = 0.009). The study showed that PD-L1 expression on immune cells in the microenvironment was associated with prognosis among patients with PCNS-DLBCL.

Postoperative stroke and neurological outcomes in the early phase after revascularization surgeries for moyamoya disease: an age-stratified comparative analysis.

Stroke and neurological outcomes in the early phase following revascularization for moyamoya disease (MMD) may depend on the patient's age. In this study, an age-stratified comparative analysis was performed to clarify this issue. We reviewed 105 MMD patients who underwent 179 revascularization surgeries. The demographic characteristics were collected in four age groups (≤ 5 and 6-17 years for pediatric patients and 18-49 and ≥ 50 years for adults). Additionally, we assessed the incidence of subsequent stroke and deterioration of modified Rankin Scale (mRS) score. Then, we evaluated predictors of postoperative stroke and mRS deterioration using logistic regression. The mean patient age was 26.2 ± 18.5 years. No significant difference in the incidence of postoperative stroke was observed between age groups; however, the incidence tended to be increased among patients aged ≤ 5 years (17.9%) and patients aged ≥ 50 years (16.7%). Deterioration of mRS scores was significantly associated with ages ≤ 5 years (17.9%) and ≥ 50 years (11.1%). Logistic regression showed that posterior cerebral artery involvement (odds ratio [OR], 4.6) and postoperative transient neurological events (TNEs) (OR, 5.93) were risk factors for postoperative stroke. Age ≤ 5 years (OR, 9.73), postoperative TNEs (OR, 7.38), and postoperative stroke (OR, 49) were identified as predictors of unfavorable neurological outcomes. The novel feature of this comparative analysis by age group is that membership in the early-childhood MMD patient group (under 5 years old) was an independent risk factor for unfavorable short-term neurological outcomes and was mainly associated with the incidence of postoperative severe cerebral infarction.

Transcriptome-wide analysis of intracranial artery in patients with moyamoya disease showing upregulation of immune response, and downregulation of oxidative phosphorylation and DNA repair.

OBJECTIVE: Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive occlusion of the internal carotid artery and the secondary formation of collateral vessels. Patients with MMD have ischemic attacks or intracranial bleeding, but the disease pathophysiology remains unknown. In this study, the authors aimed to identify a gene expression profile specific to the intracranial artery in MMD. METHODS: This was a single-center, prospectively sampled, retrospective cohort study. Microsamples of the middle cerebral artery (MCA) were collected from patients with MMD (n = 11) and from control patients (n = 9). Using microarray techniques, transcriptome-wide analysis was performed. RESULTS: Comparison of MCA gene expression between patients with MMD and control patients detected 62 and 26 genes whose expression was significantly (p < 0.001 and fold change > 2) up- or downregulated, respectively, in the MCA of MMD. Gene set enrichment analysis of genes expressed in the MCA of patients with MMD revealed positive correlations with genes involved in antigen processing and presentation, the dendritic cell pathway, cytokine pathway, and interleukin-12 pathway, and negative correlations with genes involved in oxidative phosphorylation and DNA repair. Microarray analysis was validated by quantitative polymerase chain reaction. CONCLUSIONS: Transcriptome-wide analysis showed upregulation of genes for immune responses and downregulation of genes for DNA repair and oxidative phosphorylation within the intracranial artery of patients with MMD. These findings may represent clues to the pathophysiology of MMD.

[Magnetic Resonance-guided Focused Ultrasound Ablation:Techniques and Neurological Applications].

Magnetic resonance(MR)-guided focused ultrasound ablation(FUS)is a minimally invasive technique for targeted tissue thermo-ablation and is promising for neuromodulation in various neurological disorders. The effectiveness and safety of this technique have been recognized worldwide. In Japan, the applications of FUS for the treatment of essential tremors and Parkinson's disease have recently been covered under health insurance. The FUS system is composed of a phased-array transducer with 1024 elements, with a beam of ultrasound emerging from each element. The phase and amplitude of the beam are computed and controlled to focus on the target with the calculation of computed tomography(CT)profiles, resulting in optimal thermo-ablation. To utilize FUS safely and effectively, a deep understanding of the physics of this technology is necessary. Furthermore, the technique should be compared with other options including deep brain stimulation(DBS)and radiofrequency thermo-ablation. Although FUS has received attention because of minimally invasive characteristics and a possibility of procedural target refinement, DBS has some advantages on bilateral implantation, a potential of postoperative adjustment, and control of head/leg tremors. In this article, we first reviewed the physics of FUS and demonstrated the typical treatment protocols. Second, we reviewed the outcomes from the existing literature, and revealed the advantages and disadvantages of this procedure, with the evaluation of the optimal condition for FUS.

Identifying the brain's connector hubs at the voxel level using functional connectivity overlap ratio.

Neuroimaging studies have shown that the brain is functionally organized into several large-scale brain networks. Within these networks are regions that are widely connected to several other regions within and/or outside the network. Regions that connect to several other networks, known as connector hubs, are believed to be crucial for information transfer and between-network communication within the brain. To identify regions with high between-network connectivity at the voxel level, we introduced a novel metric called functional connectivity overlap ratio (FCOR), which quantifies the spatial extent of a region's connection to a given network. Using resting state functional magnetic resonance imaging data, FCOR maps were generated for several well-known large-scale resting state networks (RSNs) and used to examine the relevant associations among different RSNs, identify connector hub regions in the cerebral cortex, and elucidate the hierarchical functional organization of the brain. Constructed FCOR maps revealed a strong association among the core neurocognitive networks (default mode, salience, and executive control) as well as among primary processing networks (sensorimotor, auditory, and visual). Prominent connector hubs were identified in the bilateral middle frontal gyrus, posterior cingulate, lateral parietal, middle temporal, dorsal anterior cingulate, and anterior insula, among others, regions mostly associated with the core neurocognitive networks. Finally, clustering the whole brain using FCOR features yielded a topological organization that arranges brain regions into a hierarchy of information processing systems with the primary processing systems at one end and the heteromodal systems comprising connector hubs at the other end.

Changes in white matter fiber density and morphology across the adult lifespan: A cross-sectional fixel-based analysis.

White matter (WM) fiber bundles change dynamically with age. These changes could be driven by alterations in axonal diameter, axonal density, and myelin content. In this study, we applied a novel fixel-based analysis (FBA) framework to examine these changes throughout the adult lifespan. Using diffusion-weighted images from a cohort of 293 healthy volunteers (89 males/204 females) from ages 21 to 86 years old, we performed FBA to analyze age-related changes in microscopic fiber density (FD) and macroscopic fiber morphology (fiber cross section [FC]). Our results showed significant and widespread age-related alterations in FD and FC across the whole brain. Interestingly, some fiber bundles such as the anterior thalamic radiation, corpus callosum, and superior longitudinal fasciculus only showed significant negative relationship with age in FD values, but not in FC. On the other hand, some segments of the cerebello-thalamo-cortical pathway only showed significant negative relationship with age in FC, but not in FD. Analysis at the tract-level also showed that major fiber tract groups predominantly distributed in the frontal lobe (cingulum, forceps minor) exhibited greater vulnerability to the aging process than the others. Differences in FC and the combined measure of FD and cross section values observed between sexes were mostly driven by differences in brain sizes although male participants tended to exhibit steeper negative linear relationship with age in FD as compared to female participants. Overall, these findings provide further insights into the structural changes the brain's WM undergoes due to the aging process.

PD-L1 and PD-L2 expression in the tumor microenvironment including peritumoral tissue in primary central nervous system lymphoma.

BACKGROUND: The prevalence of programmed death-ligand 1 (PD-L1) and PD-L2 expression on tumor cells and tumor-infiltrating immune cells in primary central nervous system lymphoma (PCNSL) remains unclear. In the present study, we analyzed needle biopsy and craniotomy specimens of patients with PCNSL to compare the PD-L1 and PD-L2 levels in the tumor and surrounding (peritumoral) tissue. We also assessed the correlation between biological factors and the prognostic significance of PD-L1 and PD-L2 expression. METHODS: We retrospectively analyzed the cases of 70 patients histologically diagnosed with PCNSL (diffuse large B-cell lymphoma). Immunohistochemistry for CD20, CD68, PD-L1, and PD-L2 was performed. In cases with specimens taken by craniotomy, the percentages of PD-L1- and PD-L2-positive macrophages were evaluated in both tumor and peritumoral tissue. The Kaplan-Meier method with log-rank test and Cox proportional hazard model were used for survival analysis. RESULTS: The tumor cells expressed little or no PD-L1 and PD-L2, but macrophages expressed PD-L1 and PD-L2 in most of the patients. The median percentage of PD-L2-positive cells was significantly higher among peritumoral macrophages (32.5%; 95% CI: 0-94.6) than intratumoral macrophages (27.5%; 95% CI: 0-81.1, p = 0.0014). There was a significant correlation between the percentages of PD-L2-positive intratumoral macrophages and PD-L2-positive peritumoral macrophages (p = 0.0429), with very low coefficient correlation (ρ = 0.098535). PD-L1 expression on macrophages was significantly associated with biological factors (intratumoral macrophages: better KPS, p = 0.0008; better MSKCC score, p = 0.0103; peritumoral macrophages: low proportion of LDH elevation, p = 0.0064) and longer OS (for intratumoral macrophages: high PD-L1 = 60 months, 95% CI = 30-132.6; low PD-L1 = 24 months, 95% CI = 11-48; p = 0.032; for peritumoral macrophages: high PD-L1 = 60 months, 95% CI = 30.7-NR; low PD-L1 = 14 months, 95% CI = 3-26). PD-L1 expression on peritumoral macrophages was strongly predictive of a favorable outcome (HR = 0.30, 95% CI = 0.12-0.77, p = 0.0129). CONCLUSIONS: Macrophages in intratumoral and peritumoral tissue expressed PD-L1 and PD-L2 at a higher rate than tumor cells. PD-L1 expression, especially on peritumoral macrophages, seems to be an important prognostic factor in PCNSL. Future comprehensive analysis of checkpoint molecules in the tumor microenvironment, including the peritumoral tissue, is warranted.

Preoperative predictive factors affecting return to work in patients with gliomas undergoing awake brain mapping.

PURPOSE: This study aimed to investigate the preoperative predictive factors affecting return to work in patients with gliomas in the left cerebral hemisphere undergoing awake surgery. METHODS: We retrospectively reviewed 50 consecutive glioma patients who underwent awake surgery from January 2012 to July 2017. Adult patients older than 18 years, who reported working prior to surgery, were recruited for this study. RESULTS: Comparing sociodemographic, disease-related and preoperative neurocognitive variables of glioma patients who returned to work and those who did not, binomial logistic regression models for preoperative predictors affecting return to work revealed significant differences in age and sole breadwinner status as sociodemographic variables, tumour volume as a disease-related variable, and Verbal IQ, Performance IQ, general memory, attention/concentration, and working memory as neurocognitive variables. Multivariate logistic regression models demonstrated that the independent factors associated with propriety of returning to work 1 year after surgery was the sociodemographic variable sole breadwinner status (yes vs no; OR = 15.00, 95% CI 2.22-101.35, p = 0.01), the disease-related variable tumour volume (per 1 cm3; OR = 0.98, 95% CI 0.96-0.99, p = 0.04), and the preoperative neurocognitive variable general memory (≥ 100 vs < 100; OR = 21.70, 95% CI 2.60-183.94, p = 0.01). CONCLUSIONS: Our results suggest that three predictive factors including sole breadwinner status, tumour volume and general memory that can be assessed in the preoperative stage substantially contribute to returning to work in patients with gliomas in the left cerebral hemisphere, 1 year after awake surgery.

Genetic analysis in patients with newly diagnosed glioblastomas treated with interferon-beta plus temozolomide in comparison with temozolomide alone.

PURPOSE: This study aimed to explore the genetic alterations and to identify good responders in the experimental arm in the tumor samples from newly diagnosed glioblastoma (GBM) patients enrolled in JCOG0911; a randomized phase II trial was conducted to compare the efficacy of interferonß (IFNß) plus temozolomide (TMZ) with that of TMZ alone. EXPERIMENTAL: DESIGN: Of 122 tumors, we performed deep targeted sequencing to determine the somatic mutations, copy number variations, and tumor mutation burden; pyrosequencing for O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation; Sanger sequencing for the telomerase reverse transcriptase (TERT) promoter; and microsatellite instability (MSI) testing in 95, 91, 91 and 72 tumors, respectively. We performed a multivariable Cox regression analysis using backward stepwise selection of variables including clinical factors (sex, age, performance status, residual tumor after resection, tumor location) and genetic alterations. RESULTS: Deep sequencing detected an IDH1 mutation in 13 tumors (14%). The MGMT promoter methylation by quantitative pyrosequencing was observed in 41% of the tumors. A mutation in the TERT promoter was observed in 69% of the tumors. While high tumor mutation burden (> 10 mutations per megabase) was seen in four tumors, none of the tumors displayed MSI-high. The clinical and genetic factors considered as independent favorable prognostic factors were gross total resection (hazard ratio [HR]: 0.49, 95% confidence interval, 0.30-0.81, P = 0.0049) and MGMT promoter methylation (HR: 0.43, 0.21-0.88, P = 0.023). However, tumor location at the temporal lobe (HR: 1.90, 1.22-2.95, P = 0.0046) was an independent unfavorable prognostic factor. No predictive factors specific to the TMZ + IFNß + Radiotherapy (RT) group were found. CONCLUSION: This additional sub-analytical study of JCOG0911 among patients with newly diagnosed GBM showed that tumor location at the temporal lobe, gross total resection, and MGMT promoter methylation were significant prognostic factors, although no factors specific to IFNß addition were identified.

Peel-off resection of the pituitary gland for functional pituitary adenomas: pathological significance and impact on pituitary function.

PURPOSE: Functional pituitary adenomas (FPAs) lacking a well-defined pseudocapsule can invade the adjacent pituitary gland. In such situations, peel-off resection of the adjacent pituitary gland after selective adenomectomy might lead to complete tumor removal, resulting in optimal endocrinological outcomes. Here, we present the significance of peel-off resection of the pituitary gland in patients with FPA in whom complete extracapsular tumor removal cannot be achieved. METHODS: We performed a retrospective review of 21 patients with FPA who underwent transsphenoidal surgery (TSS). After selective adenomectomy, peel-off resection of the adjacent pituitary gland was performed in 13 patients because complete extracapsular resection could not be achieved, while peel-off resection was not performed in the remaining 8 patients because complete extracapsular resection was accomplished. The clinical outcomes of these groups were compared. The pituitary tissues obtained by peel-off resection were pathologically examined for tumor cells. RESULTS: Early postoperative biochemical remission was achieved in 20 patients (95.2%). Anterior pituitary functions were not aggravated postoperatively in any patient: however, transient diabetes insipidus (DI) occurred in 2 patients. There were no statistically significant differences in the clinical outcomes of the two groups. A pseudocapsule was pathologically detected in the adjacent anterior pituitary even in patients in whom no pseudocapsule was intraoperatively detected. Tumor cells were pathologically detected in 7 (58.3%) of 12 pituitary tissues examined. CONCLUSIONS: Peel-off resection of the pituitary gland, which can remove a small tumor cell remnant in the adjacent pituitary, might maximize the effectiveness of TSS with minimal impact on postoperative pituitary function.

Next Generation Sequencing-Based Transcriptome Predicts Bevacizumab Efficacy in Combination with Temozolomide in Glioblastoma.

Glioblastoma (GBM), the most common and malignant brain tumor, is classified according to its isocitrate dehydrogenase (IDH) mutation status in the 2016 World Health Organization (WHO) brain tumor classification scheme. The standard treatment for GBM is maximal resection, radiotherapy, and Temozolomide (TMZ). Recently, Bevacizumab (Bev) has been added to basic therapy for newly diagnosed GBM, and monotherapy for recurrent GBM. However, the effect of IDH1 mutation on the combination of Bev and TMZ is unknown. In this study, we performed transcriptomic analysis by RNA sequencing with next generation sequencing (NGS), a newly developed powerful method that enables the quantification of the expression level of genome-wide genes. Extracellular matrix and immune cell migration genes were mainly upregulated whereas cell cycle genes were downregulated in IDH1-mutant U87 cells but not in IDH1-wildtype U87 cells after adding Bev to TMZ. In vitro and in vivo studies were conducted for further investigations to verify these results, and the addition of Bev to TMZ showed a significant antitumor effect only in the IDH1-mutant GBM xenograft model. Further studies of gene expression profiling in IDH1 mutation gliomas using NGS will provide more genetic information and will lead to new treatments for this refractory disease.

An unbiased data-driven age-related structural brain parcellation for the identification of intrinsic brain volume changes over the adult lifespan.

This study aims to elucidate age-related intrinsic brain volume changes over the adult lifespan using an unbiased data-driven structural brain parcellation. Anatomical brain images from a cohort of 293 healthy volunteers ranging in age from 21 to 86 years were analyzed using independent component analysis (ICA). ICA-based parcellation identified 192 component images, of which 174 (90.6%) showed a significant negative correlation with age and with some components being more vulnerable to aging effects than others. Seven components demonstrated a convex slope with aging; 3 components had an inverted U-shaped trajectory, and 4 had a U-shaped trajectory. Linear combination of 86 components provided reliable prediction of chronological age with a mean absolute prediction error of approximately 7.2 years. Structural co-variation analysis showed strong interhemispheric, short-distance positive correlations and long-distance, inter-lobar negative correlations. Estimated network measures either exhibited a U- or an inverted U-shaped relationship with age, with the vertex occurring at approximately 45-50 years. Overall, these findings could contribute to our knowledge about healthy brain aging and could help provide a framework to distinguish the normal aging processes from that associated with age-related neurodegenerative diseases.

Subarachnoid hemorrhage induces neuronal nitric oxide synthase phosphorylation at Ser1412 in the dentate gyrus of the rat brain.

INTRODUCTION: We previously demonstrated that cyclic AMP-dependent protein kinase (PKA) phosphorylates neuronal nitric oxide synthase (nNOS) at Ser1412 in the hippocampal dentate gyrus after forebrain ischemia; this phosphorylation event activates NOS activity and might contribute to depression after cerebral ischemia. In this study, we revealed chronological and topographical changes in the phosphorylation of nNOS at Ser1412 immediately after subarachnoid hemorrhage (SAH). METHODS: In a rat single-hemorrhage model of SAH, the hippocampus and adjacent cortex were collected up to 24 h after SAH. Samples from rats that were not injected with autologous blood were used as controls. NOS was partially purified from crude samples via an ADP-agarose gel. Levels of nNOS, nNOS phosphorylated at Ser1412 (p-nNOS), PKA, and p-PKA at Thr197 were studied in the rat hippocampus and cortex using Western blot analyses and immunohistochemistry. RESULTS: According to the Western blot analysis, levels of p-nNOS at Ser1412 were significantly increased in the hippocampus, but not in the cortex, between 1 and 3 h after SAH. Immunohistochemistry revealed the phosphorylation of nNOS at Ser1412 and PKA at Thr197 in the dentate gyrus, but not in the CA1 area, 1 h after SAH. An injection of saline instead of blood also significantly increased levels of p-nNOS at Ser1412 in the hippocampus 1 h after the injection. CONCLUSIONS: An immediate increase in intracranial pressure (ICP) might induce transient cerebral ischemia and promote the PKA-mediated phosphorylation of nNOS at Ser1412 in the dentate gyrus. This signal transduction pathway induces the excessive production of nitric oxide (NO) and might be involved in cognitive dysfunction after SAH.

JCOG0911 INTEGRA study: a randomized screening phase II trial of interferonß plus temozolomide in comparison with temozolomide alone for newly diagnosed glioblastoma.

PURPOSE: This study explored the superiority of temozolomide (TMZ) + interferonß (IFNß) to standard TMZ as treatment for newly diagnosed glioblastoma (GBM) via randomized phase II screening design. EXPERIMENTAL DESIGN: Eligibility criteria included histologically proven GBM, with 50% of the tumor located in supratentorial areas, without involvement of the optic, olfactory nerves, and pituitary gland and without multiple lesions and dissemination. Patients in the TMZ + radiotherapy (RT) arm received RT (2.0 Gy/fr/day, 30 fr) with TMZ (75 mg/m2, daily) followed by TMZ maintenance (100-200 mg/m2/day, days 1-5, every 4 weeks) for 2 years. Patients in the TMZ + IFNß + RT arm intravenously received IFNß (3 MU/body, alternative days during RT and day 1, every 4 weeks during maintenance period) and TMZ + RT. The primary endpoint was overall survival (OS). The planned sample size was 120 (one-sided alpha 0.2; power 0.8). RESULTS: Between Apr 2010 and Jan 2012, 122 patients were randomized. The median OS with TMZ + RT and TMZ + IFNß + RT was 20.3 and 24.0 months (HR 1.00, 95% CI 0.65-1.55; one-sided log rank P = 0.51). The median progression-free survival times were 10.1 and 8.5 months (HR 1.25, 95% CI 0.85-1.84). The incidence of neutropenia with the TMZ + RT and the TMZ + IFNß + RT (grade 3-4, CTCAE version 3.0) was 12.7 versus 20.7% during concomitant period and was 3.6 versus 9.3% during maintenance period. The incidence of lymphopenia was 54.0 versus 63.8% and 34.5 versus 41.9%. CONCLUSIONS: TMZ + IFNß + RT is not considered as a candidate for the following phase III trial, and TMZ + RT remained to be a most promising treatment. This trial was registered with the UMIN Clinical Trials Registry: UMIN000003466.

Significance of perivascular tumour cells defined by CD109 expression in progression of glioma.

In the progression of glioma, tumour cells often exploit the perivascular microenvironment to promote their survival and resistance to conventional therapies. Some of these cells are considered to be brain tumour stem cells (BTSCs); however, the molecular nature of perivascular tumour cells has not been specifically clarified because of the complexity of glioma. Here, we identified CD109, a glycosylphosphatidylinositol-anchored protein and regulator of multiple signalling pathways, as a critical regulator of the progression of lower-grade glioma (World Health Organization grade II/III) by clinicopathological and whole-genome sequencing analysis of tissues from human glioma. The importance of CD109-positive perivascular tumour cells was confirmed not only in human lower-grade glioma tissues but also in a mouse model that recapitulated human glioma. Intriguingly, BTSCs isolated from mouse glioma expressed high levels of CD109. CD109-positive BTSCs exerted a proliferative effect on differentiated glioma cells treated with temozolomide. These data reveal the significance of tumour cells that populate perivascular regions during glioma progression, and indicate that CD109 is a potential therapeutic target for the disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.