Discovery of novel glioma serum biomarkers by proximity extension assay.

BACKGROUND: Gliomas are among the most malignant tumors, with a very poor prognosis. Early diagnosis is highly desirable since it can help implement more effective treatments for smaller tumors, which have not yet extensively metastasized. Improving early diagnosis may facilitate access of patients to clinical trials and prepare them for the future availability of new disease-modifying treatments. METHODS: We analyzed retrospective samples collected at diagnosis (before therapy initiation), with PEA (Olink Proteomics), quantifying about 3000 proteins. We utilized 30 plasmas from gliomas (20 glioblastomas, 5 anaplastic astrocytomas, 5 anaplastic oligodendrogliomas) and 20 meningiomas (as controls). We then analyzed the data to identify proteins which either alone, or in combination, could discriminate gliomas from meningiomas, or correlate with clinical and molecular alterations. RESULTS: We identified 8 plasma proteins which were increased in gliomas vs. meningiomas (GFAP, NEFL, EDDM3B, PROK1, MMP3, CTRL, GP2, SPINT3) and 4 proteins which were decreased in gliomas vs. meningiomas (FABP4, ALDH3A1, IL-12B and OXT). Partition algorithms and logistic regression algorithms with two biomarkers (GFAP and FABP4) achieved sensitivity of 83% and 93% at 100% and 90% specificity, respectively. The strongest single marker was GFAP with an area under the ROC curve (AUC) of 0.86. The AUC for the GFAP-FABP4 combination was 0.98. CONCLUSION: PEA is a powerful new proteomic technology for biomarker discovery. GFAP and a handful of other plasma biomarkers may be useful for early glioma detection and probably, prognosis. STATEMENT: Detecting gliomas as early as possible is highly desirable since it can significantly improve the chances of effective treatments. Reliable glioma biomarkers can timely inform glioma patients about the efficacy of their prescribed treatment. Our results reveal some novel putative glioma markers that may prove valuable, when used alone or in combination, towards improved clinical care of gliomas. In order to better appreciate the potential usefulness of these markers, their performance needs to be further validated in a larger cohort of samples.

Deciphering of Adult Glioma Vulnerabilities through Expression Pattern Analysis of GABA, Glutamate and Calcium Neurotransmitter Genes.

Adult infiltrating gliomas are highly aggressive tumors of the central nervous system with a dismal prognosis despite intensive multimodal therapy (chemotherapy and/or radiotherapy). In this study, we studied the expression, methylation and interacting miRNA profiles of GABA-, glutamate- and calcium-related genes in 661 adult infiltrating gliomas available through the TCGA database. Neurotransmitter-based unsupervised clustering identified three established glioma molecular subgroups that parallel major World Health Organization glioma subclasses (IDH-wildtype astrocytomas, IDH-mutant astrocytomas, IDH-mutant oligodendroglioma). In addition, this analysis also defined a novel, neurotransmitter-related glioma subgroup (NT-1), mostly comprised of IDH-mutated gliomas and characterized by the overexpression of neurotransmitter-related genes. Lower expression of neurotransmission-related genes was correlated with increased aggressivity in hypomethylated IDH-wildtype tumors. There were also significant differences in the composition of the tumor inflammatory microenvironment between neurotransmission-based tumor categories, with lower estimated pools of M2-phenotype macrophages in NT-1 gliomas. This multi-omics analysis of the neurotransmission expression landscape of TCGA gliomas-which highlights the existence of neurotransmission-based glioma categories with different expression, epigenetic and inflammatory profiles-supports the existence of operational neurotransmitter signaling pathways in adult gliomas. These findings could shed new light on potential vulnerabilities to exploit in future glioma-targeting drug therapies.

Topographic mapping of the glioblastoma proteome reveals a triple-axis model of intra-tumoral heterogeneity.

Glioblastoma is an aggressive form of brain cancer with well-established patterns of intra-tumoral heterogeneity implicated in treatment resistance and progression. While regional and single cell transcriptomic variations of glioblastoma have been recently resolved, downstream phenotype-level proteomic programs have yet to be assigned across glioblastoma's hallmark histomorphologic niches. Here, we leverage mass spectrometry to spatially align abundance levels of 4,794 proteins to distinct histologic patterns across 20 patients and propose diverse molecular programs operational within these regional tumor compartments. Using machine learning, we overlay concordant transcriptional information, and define two distinct proteogenomic programs, MYC- and KRAS-axis hereon, that cooperate with hypoxia to produce a tri-dimensional model of intra-tumoral heterogeneity. Moreover, we highlight differential drug sensitivities and relative chemoresistance in glioblastoma cell lines with enhanced KRAS programs. Importantly, these pharmacological differences are less pronounced in transcriptional glioblastoma subgroups suggesting that this model may provide insights for targeting heterogeneity and overcoming therapy resistance.

Automated detection and quantification of breast cancer brain metastases in an animal model using democratized machine learning tools.

Advances in digital whole-slide imaging and machine learning (ML) provide new opportunities for automated examination and quantification of histopathological slides to support pathologists and biologists. However, implementation of ML tools often requires advanced skills in computer science that may not be immediately available in the traditional wet-lab environment. Here, we propose a simple and accessible workflow to automate detection and quantification of brain epithelial metastases on digitized histological slides. We leverage 100 Hematoxylin & Eosin (H&E)-stained whole slide images (WSIs) from 25 Balb/c mice with various level of brain metastatic tumor burden. A supervised training of the Trainable Weka Segmentation (TWS) from Fiji was achieved from annotated WSIs. Upon comparison with manually drawn regions, it is apparent that the algorithm learned to identify and segment cancer cell-specific nuclei and normal brain tissue. Our approach resulted in a robust and highly concordant correlation between automated metastases quantification of brain metastases and manual human assessment (R2 = 0.8783; P < 0.0001). This simple approach is amenable to other similar analyses, including that of human tissues. Widespread adoption of these tools aims to democratize ML and improve precision in traditionally qualitative tasks in histopathology-based research.

Stalled developmental programs at the root of pediatric brain tumors.

Childhood brain tumors have suspected prenatal origins. To identify vulnerable developmental states, we generated a single-cell transcriptome atlas of >65,000 cells from embryonal pons and forebrain, two major tumor locations. We derived signatures for 191 distinct cell populations and defined the regional cellular diversity and differentiation dynamics. Projection of bulk tumor transcriptomes onto this dataset shows that WNT medulloblastomas match the rhombic lip-derived mossy fiber neuronal lineage and embryonal tumors with multilayered rosettes fully recapitulate a neuronal lineage, while group 2a/b atypical teratoid/rhabdoid tumors may originate outside the neuroectoderm. Importantly, single-cell tumor profiles reveal highly defined cell hierarchies that mirror transcriptional programs of the corresponding normal lineages. Our findings identify impaired differentiation of specific neural progenitors as a common mechanism underlying these pediatric cancers and provide a rational framework for future modeling and therapeutic interventions.

Fatal awake malignant hyperthermia episodes in a family with malignant hyperthermia susceptibility: a case series.

PURPOSE: The present report of two fatal awake malignant hyperthermia (MH) episodes in an MH susceptible (MHS) family is intended to raise awareness among medical personnel and MHS individuals to the possibility of life-threatening non-anesthesia-triggered MH episodes and to provide a strong incentive for development of effective preventive measures. CLINICAL FEATURES: Two young athletic males (28 and 16 yr old), members of the same extended family with a history of anesthesia-related MH episodes and deaths, succumbed ten years apart on two different continents, with symptoms unrelated to anesthesia but strikingly similar to typical anesthetic-induced MH. Both suffered an abrupt surge in body temperature, tachycardia, tachypnea, muscle rigidity, hyperkalemia, and respiratory and metabolic acidosis. Despite aggressive resuscitation attempts, both developed cardiac arrest and died shortly upon arrival to hospital emergency departments. Autopsy analyses were negative for drugs, alcohol, or bacterial infection. Individual and familial genetic analyses revealed a novel, potentially pathogenic RYR1 variant (p.Gly159Arg) that co-segregates with the MHS phenotype in the family. Both fatal awake MH episodes are hypothesized to have been triggered by physical exertion compounded with a febrile illness that in one case was due to influenza type A. CONCLUSIONS: Life-threatening awake MH episodes may develop in some MHS individuals in the absence of anesthetic triggers. Potential triggers can be physical exertion in combination with a febrile illness. Malignant hyperthermia susceptible patients are recommended to be vaccinated against flu and restrict physical activities when febrile, wear an MH alert bracelet, and inform medical personnel of their MH history. Oral dantrolene is suggested to be available to MHS patients for administration with the early signs of awake MH.

RéSUMé: OBJECTIF: Ce compte-rendu de deux épisodes fatals d'hyperthermie maligne (HM) survenus en communauté, sans anesthésie, dans une famille susceptible à l'HM (SHM) a pour but premier de conscientiser le personnel médical et les personnes SHM quant au risque d'épisodes d'HM potentiellement fatals et non déclenchés par l'anesthésie. Notre deuxième objectif est d'encourager fortement la mise au point de mesures préventives efficaces. ÉLéMENTS CLINIQUES: Deux jeunes hommes sportifs (28 ans et 16 ans), membres de la même famille élargie ayant des antécédents d'épisodes d'HM et de décès liés à l'anesthésie, sont décédés à dix ans d'écart, sur deux continents, de symptômes non liés à l'anesthésie mais présentant une ressemblance frappante à une crise typique d'HM induite par l'anesthésie. Les deux hommes ont souffert d'une hausse rapide de leur température corporelle, de tachycardie, de tachypnée, de rigidité musculaire, d'hyperkaliémie et d'acidose respiratoire et métabolique. Malgré des tentatives vigoureuses de réanimation, les deux sont tombés en arrêt cardiaque et sont décédés peu après leur arrivée à l'urgence. Les analyses d'autopsie étaient négatives en ce qui touchait aux drogues, à l'alcool et aux infections bactériennes. Les analyses génétiques individuelles et familiales ont révélé une nouvelle variante du gène RYR1 potentiellement pathogène (p.Gly159Arg) qui est hérité en co-ségrégation avec le phénotype de SHM dans cette famille. On pense que ces deux épisodes fatals d'HM en éveil ont été provoqués par un effort physique combiné à une maladie fébrile qui, dans l'un des cas, était due à une influenza de type A. CONCLUSION: Des épisodes fatals d'HM en éveil peuvent survenir chez certaines personnes SHM en l'absence de déclencheurs anesthésiques. L'effort physique combiné à une maladie fébrile pourrait constituer un déclencheur potentiel. Les patients susceptibles à l'hyperthermie maligne sont encouragés à se faire vacciner contre l'influenza et à limiter leurs activités physiques lorsqu'ils souffrent de fièvre, à porter un bracelet d'alerte d'HM, et à informer le personnel médical de leurs antécédents d'HM. On suggère que du dantrolène par voie orale soit mis à la disposition des patients SHM afin d'être administré dès les premiers signes d'HM en éveil.

Liposomal formulations of carboplatin injected by convection-enhanced delivery increases the median survival time of F98 glioma bearing rats.

BACKGROUND: Effectiveness of chemotherapy for treating glioblastoma (GBM) brain tumors is hampered by the blood-brain barrier which limits the entry into the brain of most drugs from the blood. To bypass this barrier, convection-enhanced delivery (CED) was proposed to directly inject drugs in tumor. However, the benefit of CED may be hampered when drugs diffuse outside the tumor to then induce neurotoxicity. Encapsulation of drugs into liposome aims at increasing tumor cells specificity and reduces neurotoxicity. However, the most appropriate liposomal formulation to inject drugs into brain tumor by CED still remains to be determined. In this study, four liposomal carboplatin formulations were prepared and tested in vitro on F98 glioma cells and in Fischer rats carrying F98 tumor implanted in the brain. Impact of pegylation on liposomal surface and relevance of positive or negative charge were assessed. RESULTS: The cationic non-pegylated (L1) and pegylated (L2) liposomes greatly improved the toxicity of carboplatin in vitro compared to free carboplatin, whereas only a modest improvement and even a reduction of efficiency were measured with the anionic non-pegylated (L3) and the pegylated (L4) liposomes. Conversely, only the L4 liposome significantly increased the median survival time of Fisher rats implanted with the F98 tumor, compared to free carboplatin. Neurotoxicity assays performed with the empty L4' liposome showed that the lipid components of L4 were not toxic. These results suggest that the positive charge on liposomes L1 and L2, which is known to promote binding to cell membrane, facilitates carboplatin accumulation in cancer cells explaining their higher efficacy in vitro. Conversely, negatively charged and pegylated liposome (L4) seems to diffuse over a larger distance in the tumor, and consequently significantly increased the median survival time of the animals. CONCLUSIONS: Selection of the best liposomal formulation based on in vitro studies or animal model can result in contradictory conclusions. The negatively charged and pegylated liposome (L4) which was the less efficient formulation in vitro showed the best therapeutic effect in animal model of GBM. These results support that relevant animal model of GBM must be considered to determine the optimal physicochemical properties of liposomal formulations.

The first case of bacillus Calmette-Guérin-induced small-vessel central nervous system vasculitis.

To present an unrecognized vascular complication of bacillus Calmette-Guérin (BCG) therapy administered for superficial bladder carcinoma. We also review the potential mimickers for primary angiitis of the central nervous system (PACNS) as well as complications of intravesical BCG therapy. An 89-year-old Caucasian man with a history of relapsing high-grade bladder carcinoma treated with intravesical BCG presented with recurring episodes of right upper limb paresthesia with clumsiness and dysarthria. Magnetic resonance imaging of the head revealed multiple predominantly left-sided frontotemporal micronodular peri-vascular lesions. Left frontal lobe biopsy showed non-necrotizing granulomatous vasculitis. Ziehl staining was negative. Initially, he was treated for PACNS but his symptoms relapsed during every attempt to taper the corticosteroids. Six months later, he developed bilateral mycobacterial endophthalmitis, caused by Mycobacterium bovis. Brain biopsy was reviewed and confirmed the presence of perivascular mycobacteria. A retrospective diagnosis of BCG-induced central nervous system vasculitis was made and he was treated with high-dose corticosteroids, moxifloxacin, isoniazid, ethambutol, and rifampicin. BCG is a live attenuated form of Mycobacterium bovis widely used as tuberculosis vaccination and intravesical therapy for superficial forms of bladder cancer. Systemic complications affect roughly 5% of patients and can manifest months or years after the last instillation. Cases of endophthalmitis, meningitis, aortitis, or mycotic aneurysms have been described, but no reports of CNS vasculitis have been found. In disseminated forms of BCG infections, referred to as BCGitis, histopathology usually reveals granulomatous inflammation. Mycobacterial cultures are often negative, making this a diagnostic challenge. This is the first documented case of BCG-induced small-vessel CNS vasculitis. Mycobacterium bovis infection is rare and findings are often nonspecific, making the diagnosis very difficult. Other infectious and non-infectious causes must be ruled out appropriately before considering this entity.

Discordant Grading of Aortic Stenosis Severity: Echocardiographic Predictors of Survival Benefit Associated With Aortic Valve Replacement.

OBJECTIVES: This study sought to assess the survival benefit associated with aortic valve replacement (AVR) according to different strata of echocardiographic parameters of aortic stenosis (AS) severity, and especially in patients with an aortic valve area (AVA) comprised between 0.8 cm(2) and 1 cm(2). BACKGROUND: Discordant findings between AVA (≤1.0 cm(2)) and mean gradient (MG) (<40 mm Hg) raise uncertainty regarding the actual severity of AS. Some studies suggested that the AVA threshold value to define severe AS should be decreased to 0.8 cm(2) to reconcile these discordances. METHODS: A total of 1,710 patients with documented moderate to severe AS by Doppler echocardiography were separated into 4 strata of AS severity based alternatively on AVA, indexed AVA, MG, or peak aortic jet velocity (Vpeak). We compared the survival rates of medically versus surgically treated patients. To eliminate covariate differences that may lead to biased estimates of treatment effect, a propensity matching with a greedy 5-to-1 digit-matching algorithm was used. RESULTS: Mean AVA was 0.9 ± 0.3 cm(2), mean MG 33 ± 18 mm Hg, and mean Vpeak 3.6 ± 0.9 m/s. A total of 1,030 (60%) patients underwent AVR within 3 months following echocardiographic evaluation. During a mean follow-up of 4.4 ± 3.0 years there were 469 deaths. Patients with an AVA between 0.8 cm(2) and 1.0 cm(2) had a significant observed survival benefit with AVR (hazard ratio: 0.37 [95% confidence interval: 0.21 to 0.63]; p = 0.0002). AVR was also associated with improved survival in patients with MG between 25 mm Hg and 40 mm Hg or Vpeak between 3 m/s and 4 m/s, but only in patients with concomitant AVA ≤1 cm(2) (p = 0.001 vs. p = 0.46 in patients with AVA >1 cm(2)). CONCLUSIONS: These results do not support decreasing the AVA threshold value for severity to 0.8 cm(2) and they confirm that AVR is associated with improved survival in a substantial number of patients with discordant aortic grading.

Tranexamic Acid in Chronic Subdural Hematomas (TRACS): study protocol for a randomized controlled trial.

BACKGROUND: Chronic subdural hematoma (CSDH) is one of the most frequent reason for cranial neurosurgical consultation. There is no widely accepted medical treatment for this condition. Herein, we present the protocol for the Tranexamic Acid (TXA) in Chronic Subdural Hematomas (TRACS) trial aiming at determining whether TXA can increase the rate of CSDH resolution following conservative management, lower the number of required surgical procedures and decrease the rate of CSDH recurrence following surgical evacuation. METHODS: TRACS is a multicenter, double-blind, randomized, parallel-design, placebo-controlled, phase IIB study designed to provide preliminary efficacy data as well as feasibility, safety and incidence data required to plan a larger definitive phase III trial. Consecutive patients presenting with a diagnosis of chronic subdural hematoma will be screened for eligibility. Exclusion criteria include: specific risk factors for thromboembolic disease, anticoagulant use or contraindication to TXA. A total of 130 patients will be randomized to receive either 750 mg of TXA daily or placebo until complete radiological resolution of the CSDH or for a maximum of 20 weeks. CSDH volume will be measured on serial computed tomography (CT) scanning. Cognitive function tests, quality of life questionnaires as well as functional autonomy assessments will be performed at enrollment, at 10 weeks following randomization and at 3 months following treatment cessation. During the treatment period, patients will undergo standard CSDH management with surgery being performed at the discretion of the treating physician. If surgery is performed, the CSDH and its outer membrane will be sampled for in vitro analysis. The primary outcome is the rate of CSDH resolution by 20 weeks without intervening unplanned surgical procedure. Secondary outcomes include: CSDH volume, incidence of surgical evacuation procedures, CSDH recurrence, cognitive functions, functional autonomy, quality of life, incidence of complications and length of hospital stay. Planned subgroup analyses will be performed for conservatively versus surgically managed subjects and highly versus poorly vascularized CSDH. DISCUSSION: CSDH is a frequent morbidity for which an effective medical treatment has yet to be discovered. The TRACS trial will be the first prospective study of TXA for CSDH. TRIAL REGISTRATION: NCT ID: NCT02568124 .

Impact of classic and paradoxical low flow on survival after aortic valve replacement for severe aortic stenosis.

BACKGROUND: Low flow (LF) can occur with reduced (classic) or preserved (paradoxical) left ventricular ejection fraction (LVEF). OBJECTIVES: The objective of this study was to compare outcomes of patients with low ejection fraction (LEF), paradoxical low flow (PLF), and normal flow (NF) after aortic valve replacement (AVR). METHODS: We examined 1,154 patients with severe aortic stenosis (AS) who underwent AVR with or without coronary artery bypass grafting. RESULTS: Among these patients, 206 (18%) had LEF as defined by LVEF of <50%; 319 (28%) had PLF as defined by LVEF of ≥50% but stroke volume indexed to body surface area (SVi) of ≤35 ml ∙ m(-2); and 629 (54%) had NF, as defined by LVEF of ≥50% and SVi of >35 ml ∙ m(2). Aortic valve area was lower in low flow/LVEF groups (LEF: 0.71 ± 0.20 cm(2) and PLF: 0.65 ± 0.23 cm(2) vs. NF: 0.77 ± 0.18 cm(2); p < 0.001). The 30-day mortality was higher (p < 0.001) in LEF and PLF groups than in the NF group (6.3% and 6.3% vs. 1.8%, respectively). SVi and PLF group were independent predictors of operative mortality (odds ratio [OR]: 1.18, p < 0.05; and OR: 2.97, p = 0.004; respectively). At 5 years after AVR, overall survival was 72 ± 4% in LEF group, 81 ± 2% in PLF group, and 85 ± 2% in NF group (p < 0.0001). CONCLUSIONS: Patients with LEF or PLF AS have a higher operative risk, but pre-operative risk score accounted only for LEF and lower LVEF. Patients with LEF had the worst survival outcome, whereas patients with PLF and normal flow had similar survival rates after AVR. As a major predictor of perioperative mortality, SVi should be integrated in AS patients' pre-operative evaluation.

When should we consider the diagnosis of giant cell myocarditis? Revisiting "classic" echocardiographic and clinical features of this rare pathology.

OBJECTIVES: Giant cell myocarditis is a rare and often fatal disorder. According to the American Heart Association, the American College of Cardiology Foundation, and the European Society of Cardiology scientific statements, an endomyocardial biopsy should be done to exclude giant cell myocarditis in unexplained new-onset heart failure of 2 weeks to 3 months duration associated with dilated left ventricle and new ventricular arrhythmias, or Mobitz type II second-degree, or third-degree atrioventricular heart block. CASE PRESENTATIONS: Two hundred thirty-five heart transplants were performed since May 1993 at the Institut universitaire de cardiologie et de pneumologie de Quebec, Canada. Giant cell myocarditis was found in the explanted hearts of 5 patients. The preoperative diagnosis of giant cell myocarditis was done by endomyocardial biopsy or at the installation of a left ventricular-assisted device. Patients had symptoms of progressive heart failure of subacute onset. Patients consulted at a mean 32 days after the onset of symptoms. Two patients neither had ventricular arrhythmia nor heart block. Two patients had ventricular arrhythmias and heart block; the other patient had symptomatic heart block. All patients had at least 2 echocardiographies. Two patients had an increase in left ventricular size, enough to reach the criteria of left ventricular dilatation according to the American Society of Echocardiography. During this time, left ventricular ejection fraction showed a rapid decline (mean 37% to 16%). CONCLUSIONS: Ventricular arrhythmia, heart block, and left ventricular dilatation initially can be absent in many patients having giant cell myocarditis with symptoms of progressive heart failure. Endo-myocardial biopsy should be quickly considered in patients with a rapid and dramatic decline of left ventricular ejection fraction, even in the absence of classic clinical and echocardiographic features of giant cell myocarditis to rapidly obtain the diagnosis of this rare but lethal disease.

Vaginal epithelioid angiosarcoma: a potential pitfall in gynecologic pathology.

OBJECTIVE: Epithelioid angiosarcoma of the vagina is a rare variant that can easily be misdiagnosed considering the much higher frequency of epithelial neoplasms at that particular site. MATERIAL AND METHODS: We report the case of a 41-year-old gravida 2, para 1, aborta 1, with no prior history of irradiation, who consulted after the discovery of 3 lesions at the lower right portion of the vagina. RESULT: The lesion consisted of epithelioid cells with high-grade nuclei and prominent nucleoli. These cells expressed CD31, CD34, factor VIII, Fli-1, vimentin, smooth muscle actin, and WT-1. Keratin 8/18 was focally positive. They were immunonegative for keratin AE1/AE3, keratin 34ßE12, keratin 7, keratin 20, S100, HMB-45, myogenin, desmin, and human herpesvirus type 8. Polymerase chain reaction-based HPV viral search was also negative. CONCLUSIONS: A broad immunohistochemical panel including antibodies against vascular differentiation markers as well as various cytokeratins allows proper diagnosis of this unusual and aggressive entity.

Romiplostim efficacy in an acute myeloid leukemia patient with transfusion refractory thrombocytopenia.

BACKGROUND: Refractoriness to platelet (PLT) transfusion is a feared, life-threatening complication in hematology-oncology patients. Despite increased PLT requirement and treatment costs, the clinical management is difficult and these patients had less favorable outcomes. CASE REPORT: We report on the efficacy of the thrombopoietic agent romiplostim in a patient with acute myeloid leukemia with chemotherapy-induced transfusion-refractory thrombocytopenia. CONCLUSION: Romiplostim could be very helpfull in the management of AML patients with transfusion refractory thrombocytopenia.