New Antibody-Free Mass Spectrometry-Based Quantification Reveals That C9ORF72 Long Protein Isoform Is Reduced in the Frontal Cortex of Hexanucleotide-Repeat Expansion Carriers

Frontotemporal dementia (FTD) is a fatal neurodegenerative disease characterized by behavioral and language disorders. The main genetic cause of FTD is an intronic hexanucleotide repeat expansion (G4C2)n in the C9ORF72 gene. A loss of function of the C9ORF72 protein associated with the allele-specific reduction of C9ORF72 expression is postulated to contribute to the disease pathogenesis. To better understand the contribution of the loss of function to the disease mechanism, we need to determine precisely the level of reduction in C9ORF72 long and short isoforms in brain tissue from patients with C9ORF72 mutations. In this study, we developed a sensitive and robust mass spectrometry (MS) method for quantifying C9ORF72 isoform levels in human brain tissue without requiring antibody or affinity reagent. An optimized workflow based on surfactant-aided protein extraction and pellet digestion was established for optimal recovery of the two isoforms in brain samples. Signature peptides, common or specific to the isoforms, were targeted in brain extracts by multiplex MS through the parallel reaction monitoring mode on a Quadrupole–Orbitrap high resolution mass spectrometer. The assay was successfully validated and subsequently applied to frontal cortex brain samples from a cohort of FTD patients with C9ORF72 mutations and neurologically normal controls without mutations. We showed that the C9ORF72 short isoform in the frontal cortices is below detection threshold in all tested individuals and the C9ORF72 long isoform is significantly decreased in C9ORF72 mutation carriers

MEVITEM—a phase I/II trial of vismodegib + temozolomide vs temozolomide in patients with recurrent/refractory medulloblastoma with Sonic Hedgehog pathway activation

Abstract Background Vismodegib specifically inhibits Sonic Hedgehog (SHH). We report results of a phase I/II evaluating vismodegib + temozolomide (TMZ) in immunohistochemically defined SHH recurrent/refractory adult medulloblastoma. Methods TMZ-naïve patients were randomized 2:1 to receive vismodegib + TMZ (arm A) or TMZ (arm B). Patients previously treated with TMZ were enrolled in an exploratory cohort of vismodegib (arm C). If the safety run showed no excessive toxicity, a Simon’s 2-stage phase II design was planned to explore the 6-month progression-free survival (PFS-6). Stage II was to proceed if arm A PFS-6 was ≥3/9 at the end of stage I. Results A total of 24 patients were included: arm A (10), arm B (5), and arm C (9). Safety analysis showed no excessive toxicity. At the end of stage I, the PFS-6 of arm A was 20% (2/10 patients, 95% unilateral lower confidence limit: 3.7%) and the study was prematurely terminated. The overall response rates (ORR) were 40% (95% CI, 12.2-73.8) and 20% (95% CI, 0.5-71.6) in arm A and B, respectively. In arm C, PFS-6 was 37.5% (95% CI, 8.8-75.5) and ORR was 22.2% (95% CI, 2.8-60.0). Among 11 patients with an expected sensitivity according to new generation sequencing (NGS), 3 had partial response (PR), 4 remained stable disease (SD) while out of 7 potentially resistant patients, 1 had PR and 1 SD. Conclusion The addition of vismodegib to TMZ did not add toxicity but failed to improve PFS-6 in SHH recurrent/refractory medulloblastoma. Prediction of sensitivity to vismodegib needs further refinements. </jats:sec

Quantitative study of nerves of the human left atrium

International audienceOBJECTIVES To quantify and study the distribution of innervation of the left atrium and the pulmonary veins in humans. BACKGROUND Damage to cardiac nerves has been hypothesized as the explanation for successful radioftequency ablation of atrial fibrillation. METHODS From January 2003 to September 2003, histologic and quantitative studies of innervation of the left atrium and the pulmonary veins was performed in 43 consecutive necropsied adult hearts (30 men and 3 women; mean age 45.5 +/- 12.4 years). The left atrium was sectioned in 1-cm slices from left to right, with the plane of section perpendicular to the long axis of the heart. Sections of the pulmonary veins at their ostia and sections 1cm away of this structure also were obtained. Nerve fiber density was counted manually for each case and expressed as the mean number per slice. RESULTS Numerous epicardial nerve fibers and ganglia having distinct patterns of distribution in the left atrium were found. Nerve density was significantly higher at the ostia of the four pulmonary veins than in their distal part (7.1 +/- 2.1 vs 5.2 +/- 1.3 for left upper pulmonary vein; 6.3 +/- 1.5 vs 5.2 +/- 1.7 for right upper pulmonary vein; 7.4 - 2 vs 5.9 +/- 2 for left lower pulmonary vein; 6.7 +/- 1.8 vs 3.9 +/- 1.3 for right lower pulmonary vein). The left superior vein was significantly more innervated than the right inferior vein (12.3 +/- 3 vs 10.6 +/- 1.4). Gradients of innervation were found from right to left (9.8 +/- 4.6 vs 18.5 +/- 6.6, P < 05) and from the front to the rear of the atrium (17.2 +/- 6.4 vs 20.7 +/- 6.5, P < 05). The same heterogeneous distribution was observed at the myocardial level but with thinner nerve fibers, making quantification difficult. Only very thin nerve fibers were present in the endocardium. CONCLUSIONS The human left atrium exhibits several gradients of innervation at discrete sites. These findings may have clinical implications for radiofrequency ablation of atrial fibrillation

La neuro-oncologie des adolescents et adultes jeunes (AJAS) : place d’une RCP nationale. Au nom de l’ANOCEF, GO-AJA et de la SFCE

International audienceThe skills of adult versus pediatric neuro-oncologists are not completely similar though additive. Because the tumors and their protocols are different and the tolerance and expected sequelae are specific. Multidisciplinary meetings including adult and pediatric neuro-oncologists are warranted to share expertise. Since 2008, a weekly national web based conference was held in France. Any patient with the following criteria could be discussed: Adolescent and Young Adults aged between 15 and 25 years, and any adult with a pediatric type pathology, including medulloblastoma, germ cell tumors, embryonic tumors, ependymoma, pilocytic astrocytoma.ResultsAttendance during the year 2015 was as follows: 42 meetings were held; the median number of cases discussed at each meeting was 4 (1 to 8); the mean number of attendants was 7 (2 to 12). One hundred and sixty-eight cases concerning 121 patients were discussed. Mean age was 30 years old (7 to 67). Forty-eight percent were discussed at diagnosis. The patients had mostly medulloblastomas (40%), germ cell tumors (11%), ependymomas (11%), pineal tumors (7%) and embryonal tumors (8%). The rate of inclusion in protocols was increased since the opening of this web conference, especially for the germ cell tumor SIOP protocol that is opened without age restriction, and in RSMA standard risk or MEVITEM relapse adult medulloblastoma protocols.ConclusionMultidisciplinary Web conference for AYAs is feasible and increases the inclusion rate in protocols. It should be developed further.Les compétences en neuro-oncologie pédiatrique et adulte sont différentes mais complémentaires car les histologies, les protocoles thérapeutiques, la tolérance à court et moyen termes et les séquelles tardives attendues sont spécifiques à chaque tranche d’âge. Depuis 2008, ont été mises en place des réunions virtuelles nationales de concertation pluridisciplinaires hebdomadaires initialement dédiées aux adolescents et jeunes adultes (AJA) (15–25 ans) suspects ou porteurs d’une tumeur du système nerveux central dont l’incidence et l’expertise sont plus importantes en milieu pédiatrique. L’expertise a par la suite aussi bénéficié aux adultes plus âgés porteurs de ces affections. En 2015, 168 cas concernant 121 patients ont été discutés lors de 46 réunions. Le nombre moyen de dossiers discutés était de 4 (1 à 8). L’âge moyen de patients présentés était de 30 ans (7 à 67). Dans 48 % des cas, la discussion portait sur la prise en charge initiale. Le nombre moyen de thérapeutes présents était de 7 (2 à 12). Les histologies concernaient principalement des médulloblastomes 40 %, tumeurs germinales malignes 11 %, épendymomes 11 %, tumeurs pinétumeurs embryonnaires 8 %. La RCP AJA a donc prouvé la faisabilité et l’intérêt d’un échange centré sur cette sous-population, entre spécialistes de la neuro-oncologie d’origine diverses. Elle a permis d’optimiser la prise en charge de ces maladies orphelines, et l’inclusion dans des protocoles nationaux et internationaux, en particulier pour les tumeurs germinales malignes intracrâniennes ouverts à tous âges, et les protocoles s’adressant aux médulloblastomes en première ligne (RSMA) ou en rechute (MEVITEM)

What does a non-response to induction chemotherapy imply in high-risk medulloblastomas?

Abstract Purpose. Some high-risk medulloblastomas (HR-MB) do not respond to induction chemotherapy, with either post-induction stable (SD) or progressive disease (PD). To date, there is no consensus regarding their optimal management. Methods. A retrospective, multicentre study of non-responder HR-MB patients treated according to the PNET HR+5 protocol (NCT00936156) between 01/01/2009 and 31/12/2018. After two courses of etoposide and carboplatin induction chemotherapy, patients with SD or PD were analyzed. Based on the clinician’s decision, the PNET HR+5 protocol was either pursued with tandem high-dose chemotherapy (HDCT) and craniospinal irradiation (CSI) (continuation group) or it was modified (switched group). Results. Forty-nine patients were identified. After induction, 37 patients had SD and 12 had PD. The outcomes were significantly better for the SD group: the 5-y PFS and OS were 52% (95% confidence interval [95% CI] 35-67) and 70% (95% CI 51-83), respectively, in the SD group and 17% (95% CI 3-41) and 13% (95% CI 1-40), respectively, in the PD group (p &lt; 0.0001). The PNET HR+5 strategy was pursued for 3 patients in the PD group, of whom only one survived. In the SD group, it was pursued for 24 patients. The 5-y PFS and the OS were 78% (95% CI 54-90) in the continuation group and 0% and 56% (95% CI 23-79), respectively, in the switched group. In the SD group, multivariate analysis revealed that MYC amplification, molecular group 3, and a switched strategy were independent prognostic factors for progression. Conclusion. Patients with post-induction SD may benefit from HDCT and CSI, whereas improvement of the way patients with early PD are treated will require new therapeutic approaches.</jats:p

Combination of Rituximab with Chemotherapy Improved Outcome of Newly Diagnosed Primary CNS Lymphoma: A Retrospective Study of 209 Unselected Patients Referred to a Single Institution

Abstract Introduction: Treatment of first-line therapy of primary CNS lymphoma (PCNSL) is based on high-dose methotrexate and cytarabine combination chemotherapy. Consolidation radiotherapy is mainly withdrawal for patients older than 60 years old regarding the excessive rate of neurological toxicity. Rituximab improved outcome of systemic diffuse large B-cell lymphoma but no data from randomized phase III trial is available to prove such outcome improvement for PCNSL. We introduced in daily practice intravenous rituximab in combination with chemotherapy for B-cell PCNSL in first-line therapy in 2004. The goal of this study is to determine whether such therapeutic modification improves PCNSL patient's outcome. Methods: Patients were from consecutive PCNSL cases (N=209) included in Leon Berard Cancer Centre registry (Lyon, France), from 1987 to 2011 (date of diagnosis). Median age of patients was 63 years (range, 26-87), 56% were male, 51% had a performance status (PS) &gt;1, 63% had an involvement of deep structures of brain, 66% a high CSF protein level, 12% a meningeal involvement and 42% a high LDH level. Of the 171 available patients, 16% had 0-1, 60% had 2-3, and 24% had 4-5 adverse IELSG prognostic scores, respectively. Patients were all treated by chemotherapy, 92% and 63% of them by high-dose methotrexate and cytarabine containing chemotherapy, respectively followed by brain radiotherapy for 108 patients (58%). Intravenous rituximab was used in combination with chemotherapy in 61 patients (29%) between 2004 and 2011. Results: No difference in term of clinical characteristics (median age, PS, tumor site, CSF protein level, meningeal involvement, LDH level) was observed between patients treated with or without rituximab in combination with chemotherapy. With the median of 86.3 months (18.2-259), the median progression free survival (PFS) and overall survival (OS) for whole series were 17.3 months (95%CI, 10.7-25.9) and 35.6 months (95%CI, 22.7-50.0), respectively. The 3-year PFS were 55.5% (95%CI, 43-67) and 31.1% (95%CI, 24-39) for patients treated or not with rituximab, respectively (P=0.001). The 3-year OS were 73.6% (95%CI, 61-83) and 39.9% (95%CI, 32-48) for patients treated or not with rituximab, respectively (P&lt;0.0001). A multivariate analysis was performed to test the impact of the addition of rituximab over clinical prognostic factors (age, PS, tumor site, CSF protein level, meningeal involvement, LDH level, IELSG score). Age&gt;60 years (HR=1.74; 95%CI, 1.22-2.46; P=0.002), meningeal involvement (HR=2.33; 95%CI 1.42-3.85; P=0.0009) and used of rituximab (HR=0.50; 95%CI, 0.32-0.78; P=0.002) were identified as independent predictors of PFS. OS was significantly influenced by age&gt;60 years (HR=1.94; 95%CI, 1.36-2.77; P=0.0002), PS (HR=1.76; 95%CI, 1.26-2.46; P=0.001), meningeal involvement (HR=2.17; 95%CI, 1.30-3.61; P=0.003) and used of rituximab (HR=0.39; 95%CI, 0.24-0.62; P=0.0001) in multivariate analysis. In a prognostic model integrating the IELSG score (0-1 vs. 2-3 vs. 4-5) (P=0.0002 for PFS and P&lt;0.0001 for OS), used of rituximab was independently associated with the improvement of PFS (HR=0.60; 95%CI, 0.39-0.91; P=0.02) and OS (HR=0.44; 95%CI, 0.26-0.72; P=0.001). Disease free survival including patients who reached a complete response at the end of the first-line treatment was also improved by the used of rituximab (not reached versus 3.2 years, P=0.04). We also observed in this daily practice study, a reduction of the used of radiotherapy as first-line consolidation treatment (69% vs. 34%, P&lt;0.001) before (1987-2003) and after (2004-2011) rituximab period. Conclusion: In this retrospective analysis, we showed that PCNSL patients treated with intravenous rituximab in combination with first-line chemotherapy had a better outcome. The frequency of consolidation radiotherapy was reduced for these patients treated at rituximab era. In multivariate analysis, CSF involvement was an independent adverse prognostic factor that inclines to improve meningeal explorations and propose new therapeutic options for CSF positive PCNSL patients. Disclosures No relevant conflicts of interest to declare. </jats:sec

Diffuse gliomas with FGFR3-TACC3 fusion have characteristic histopathological and molecular features

International audienceAdult glioblastomas, IDH-wildtype represent a heterogeneous group of diseases. They are resistant to conventional treatment by concomitant radiochemotherapy and carry a dismal prognosis. The discovery of oncogenic gene fusions in these tumors has led to prospective targeted treatments, but identification of these rare alterations in practice is challenging. Here, we report a series of 30 adult diffuse gliomas with an in frame FGFR3-TACC3 oncogenic fusion (n = 27 WHO grade IV and n = 3 WHO grade II) as well as their histological and molecular features. We observed recurrent morphological features (monomorphous ovoid nuclei, nuclear palisading and thin parallel cytoplasmic processes, endocrinoid network of thin capillaries) associated with frequent microcalcifications and desmoplasia. We report a constant immunoreactivity for FGFR3, which is a valuable method for screening for the FGFR3-TACC3 fusion with 100% sensitivity and 92% specificity. We confirmed the associated molecular features (typical genetic alterations of glioblastoma, except the absence of EGFR amplification, and an increased frequency of CDK4 and MDM2 amplifications). FGFR3 immunopositivity is a valuable tool to identify gliomas that are likely to harbor the FGFR3-TACC3 fusion for inclusion in targeted therapeutic trials

The lipid phosphatase Synaptojanin 1 undergoes a significant alteration in expression and solubility and is associated with brain lesions in Alzheimer’s disease

Abstract Synaptojanin 1 (SYNJ1) is a brain-enriched lipid phosphatase critically involved in autophagosomal/endosomal trafficking, synaptic vesicle recycling and metabolism of phosphoinositides. Previous studies suggest that SYNJ1 polymorphisms have significant impact on the age of onset of Alzheimer’s disease (AD) and that SYNJ1 is involved in amyloid-induced toxicity. Yet SYNJ1 protein level and cellular localization in post-mortem human AD brain tissues have remained elusive. This study aimed to examine whether SYNJ1 localization and expression are altered in post-mortem AD brains. We found that SYNJ1 is accumulated in Hirano bodies, plaque-associated dystrophic neurites and some neurofibrillary tangles (NFTs). SYNJ1 immunoreactivity was higher in neurons and in the senile plaques in AD patients carrying one or two ApolipoproteinE (APOE) ε4 allele(s). In two large cohorts of APOE -genotyped controls and AD patients, SYNJ1 transcripts were significantly increased in AD temporal isocortex compared to control. There was a significant increase in SYNJ1 transcript in APOEε4 carriers compared to non-carriers in AD cohort. SYNJ1 was systematically co-enriched with PHF-tau in the sarkosyl-insoluble fraction of AD brain. In the RIPA-insoluble fraction containing protein aggregates, SYNJ1 proteins were significantly increased and observed as a smear containing full-length and cleaved fragments in AD brains. In vitro cleavage assay showed that SYNJ1 is a substrate of calpain, which is highly activated in AD brains. Our study provides evidence of alterations in SYNJ1 mRNA level and SYNJ1 protein degradation, solubility and localization in AD brains.info:eu-repo/semantics/publishe

Induction of amyloid-β deposits from serially transmitted, histologically silent, Aβ seeds issued from human brains

International audienceIn humans, iatrogenic transmission of cerebral amyloid-β (Aβ)-amyloidosis is suspected following inoculation of pituitary-derived hormones or dural grafts presumably contaminated with Aβ proteins as well as after cerebral surgeries. Experimentally, intracerebral inoculation of brain homogenate extracts containing misfolded Aβ can seed Aβ deposition in transgenic mouse models of amyloidosis or in non-human primates. The transmission of cerebral Aβ is governed by the host and by the inoculated samples. It is critical to better characterize the propensities of different hosts to develop Aβ deposition after contamination by an Aβ-positive sample as well as to better assess which biological samples can transmit this lesion. Aβ precursor protein (huAPP wt) mice express humanized non-mutated forms of Aβ precursor protein and do not spontaneously develop Aβ or amyloid deposits. We found that inoculation of Aβ-positive brain extracts from Alzheimer patients in these mice leads to a sparse Aβ deposition close to the alveus 18 months post-inoculation. However, it does not induce cortical or hippocampal Aβ deposition. Secondary inoculation of apparently amyloid deposit-free hippocampal extracts from these huAPP wt mice to APP swe /PS1 dE9 mouse models of amyloidosis enhanced Aβ deposition in the alveus 9 months post-inoculation. This suggests that Aβ seeds issued from human brain samples can persist in furtive forms in brain tissues while maintaining their ability to foster Aβ deposition in receptive hosts that overexpress endogenous Aβ. This work emphasizes the need for high-level preventive measures, especially in the context of neurosurgery, to prevent the risk of iatrogenic transmission of Aβ lesions from samples with sparse amyloid markers