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Childhood posterior fossa (PF) ependymomas cause substantial morbidity and mortality. These tumors lack recurrent genetic mutations, but a subset of these ependymomas exhibits CpG island (CpGi) hypermethylation [PF group A (PFA)], implicating epigenetic alterations in their pathogenesis. Further, histological grade does not reliably predict prognosis, highlighting the importance of developing more robust prognostic markers. We discovered global H3K27me3 reduction in a subset of these tumors (PF-ve ependymomas) analogous to H3K27M mutant gliomas. PF-ve tumors exhibited many clinical and biological similarities with PFA ependymomas. Genomic H3K27me3 distribution showed an inverse relationship with CpGi methylation, suggesting that CpGi hypermethylation drives low H3K27me3 in PF-ve ependymomas. Despite CpGi hypermethylation and global H3K27me3 reduction, these tumors showed DNA hypomethylation in the rest of the genome and exhibited increased H3K27me3 genomic enrichment at limited genomic loci similar to H3K27M mutant gliomas. Combined integrative analysis of PF-ve ependymomas with H3K27M gliomas uncovered common epigenetic deregulation of select factors that control radial glial biology, and PF radial glia in early human development exhibited reduced H3K27me3. Finally, H3K27me3 immunostaining served as a biomarker of poor prognosis and delineated radiologically invasive tumors, suggesting that reduced H3K27me3 may be a prognostic indicator in PF ependymomas.

With the success of immunotherapy in cancer, understanding the tumor immune microenvironment (TIME) has become increasingly important; however in pediatric brain tumors this remains poorly characterized. Accordingly, we developed a clinical immune-oncology gene expression assay and used it to profile a diverse range of 1382 samples with detailed clinical and molecular annotation. In low-grade gliomas we identify distinct patterns of immune activation with prognostic significance in BRAF V600E-mutant tumors. In high-grade gliomas, we observe immune activation and T-cell infiltrates in tumors that have historically been considered immune cold, as well as genomic correlates of inflammation levels. In mismatch repair deficient high-grade gliomas, we find that high tumor inflammation signature is a significant predictor of response to immune checkpoint inhibition, and demonstrate the potential for multimodal biomarkers to improve treatment stratification. Importantly, while overall patterns of immune activation are observed for histologically and genetically defined tumor types, there is significant variability within each entity, indicating that the TIME must be evaluated as an independent feature from diagnosis. In sum, in addition to the histology and molecular profile, this work underscores the importance of reporting on the TIME as an essential axis of cancer diagnosis in the era of personalized medicine. The tumour immune microenvironment remains poorly characterised in paediatric brain tumours. Here, the authors develop a clinical immune-oncology gene expression assay to profile 1382 paediatric brain tumour samples, and reveal immune profiles and biomarkers that can contribute to diagnosis, prognosis, and treatment response. [ABSTRACT FROM AUTHOR]

Background: Accurate and precise diagnosis is central to treating central nervous system (CNS) tumors, yet tissue diagnosis is often a neglected focus in low- and middle-income countries (LMICs). Since 2016, the WHO classification of CNS tumors has increasingly incorporated molecular biomarkers into the diagnosis of CNS tumors. While this shift to precision diagnostics promises a high degree of diagnostic accuracy and prognostic precision, it has also resulted in increasing divergence in diagnostic and management practices between LMICs and high-income countries (HICs). Pathologists and laboratory professionals in LMICs lack the proper training and tools to join the molecular diagnostic revolution. We describe the impact of a 7-year long twinning program between Canada and Pakistan on pathology services. Methods: During the study period, 141 challenging cases of pediatric CNS tumors initially diagnosed at Aga Khan University Hospital (AKUH), Karachi, were sent to the Hospital for Sick Children in Toronto, Canada (SickKids), for a second opinion. Each case received histologic review and often immunohistochemical staining and relevant molecular testing. A monthly multidisciplinary online tumor board (MDTB) was conducted to discuss the results with pathologists from both institutions in attendance. Results: Diagnostic discordance was seen in 30 cases. Expert review provided subclassification for 53 cases most notably for diffuse gliomas and medulloblastoma. Poorly differentiated tumors benefited the most from second review, mainly because of the resolving power of specialized immunohistochemical stains, NanoString, and targeted gene panel next-generation sequencing. Collaboration with expert neuropathologists led to validation of over half a dozen immunostains at AKUH facilitating diagnosis of CNS tumors. Conclusions: LMIC-HIC Institutional twinning provides much-needed training and mentorship to pathologists and can help in infrastructure development by adopting and validating new immunohistochemical stains. Persistent unresolved cases indicate that molecular techniques are indispensable in for diagnosis in a minority of cases. The development of affordable alternative molecular techniques may help with these histologically unresolved cases. [ABSTRACT FROM AUTHOR]

BackgroundPatients with incomplete surgical resection of medulloblastoma are controversially regarded as having a marker of high-risk disease, which leads to patients undergoing aggressive surgical resections, so-called second-look surgeries, and intensified chemoradiotherapy. All previous studies assessing the clinical importance of extent of resection have not accounted for molecular subgroup. We analysed the prognostic value of extent of resection in a subgroup-specific manner.MethodsWe retrospectively identified patients who had a histological diagnosis of medulloblastoma and complete data about extent of resection and survival from centres participating in the Medulloblastoma Advanced Genomics International Consortium. We collected from resections done between April, 1997, and February, 2013, at 35 international institutions. We established medulloblastoma subgroup affiliation by gene expression profiling on frozen or formalin-fixed paraffin-embedded tissues. We classified extent of resection on the basis of postoperative imaging as gross total resection (no residual tumour), near-total resection (30 Gy vs no craniospinal irradiation). The primary analysis outcome was the effect of extent of resection by molecular subgroup and the effects of other clinical variables on overall and progression-free survival.FindingsWe included 787 patients with medulloblastoma (86 with WNT tumours, 242 with SHH tumours, 163 with group 3 tumours, and 296 with group 4 tumours) in our multivariable Cox models of progression-free and overall survival. We found that the prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. We identified a progression-free survival benefit for gross total resection over sub-total resection (hazard ratio [HR] 1·45, 95% CI 1·07-1·96, p=0·16) but no overall survival benefit (HR 1·23, 0·87-1·72, p=0·24). We saw no progression-free survival or overall survival benefit for gross total resection compared with near-total resection (HR 1·05, 0·71-1·53, p=0·8158 for progression-free survival and HR 1·14, 0·75-1·72, p=0·55 for overall survival). No significant survival benefit existed for greater extent of resection for patients with WNT, SHH, or group 3 tumours (HR 1·03, 0·67-1·58, p=0·89 for sub-total resection vs gross total resection). For patients with group 4 tumours, gross total resection conferred a benefit to progression-free survival compared with sub-total resection (HR 1·97, 1·22-3·17, p=0·0056), especially for those with metastatic disease (HR 2·22, 1·00-4·93, p=0·050). However, gross total resection had no effect on overall survival compared with sub-total resection in patients with group 4 tumours (HR 1·67, 0·93-2·99, p=0·084).InterpretationThe prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. Although maximum safe surgical resection should remain the standard of care, surgical removal of small residual portions of medulloblastoma is not recommended when the likelihood of neurological morbidity is high because there is no definitive benefit to gross total resection compared with near-total resection.FundingCanadian Cancer Society Research Institute, Terry Fox Research Institute, Canadian Institutes of Health Research, National Institutes of Health, Pediatric Brain Tumor Foundation, and the Garron Family Chair in Childhood Cancer Research.

My work straddles non-objectivist and abstractionist approaches to art production. Abstraction uses the real to interpret and reinterpret the known world, while a non-objective method refuses the real and instead uses the elements of art to make art, disregarding the actual.  This construct is similar to the relationship between popular, classical music, and jazz. Difference here is presented through these forms. Why is abstraction misunderstood and jazz so readily understood? I suggest that because African Americans invented jazz its non-objectivity and abstraction are taken for granted and abstraction is presumed a European construction  Abstraction in the visual and plastic arts is misrecognized as incomprehensible when in fact, abstraction in the visual is imbued with similar elements as jazz; elements such as call and response, movement,, and color create, and orchestrate a compositional whole that results in a musical composition or a two dimensional composition of color, lines, and shapes.There continue to be few African American artists involved in abstraction because of its poor reception by multiple communities.  I assert that non-objective art was developed out of African motifs, (remember Picasso’s appropriation of African motifs for Les Demoiselles d’Avignon?).  Aaron Douglas was the first American, and African American, to make use of African motifs. His work should be understood as non-objective in design and abstract in content. Earlier I stated that abstraction refers to the real, Douglas’ stylized figures were abstract, and his background geometric forms non-objective. Contemporary African American abstract/non-objective art’s historicism is grounded in the work of Aaron Douglas.It has always been a penchant of mine to look at the particulars of what I see around me and reinterpret them. I use various scientific theories developed out of astrophysics, microbiology, space-time and mathematics. I wonder about cognitive science and how the eye interprets what we see; what do those signs and signifiers mean? Can the signs we take for granted be understood in some other way?In my latest work, “The Butterfly House” and “Hoot and Holler,” I use natural forms. The forms lend themselves to becoming other than that which they are. Rocks have their own history and evolutionary processes; they make their way up to the surface by natural forces, or by human beings unearthing them. They are heavy, smooth, rough and bound, too, by gravity. Yet in the mind and hands of someone like me, rocks can fly through the air, through space. What is the color of a rock? Can the color of a rock that flies, leaving the earth’s orbit, change its nature, its color? In the hands and mind of some, that rock laden and buried attains agency, and with the help of an artist whose effort is to make something a little bit interesting opens a door to a new way of being, thinking and looking.

Recurrent medulloblastoma and ependymoma are universally lethal, with no approved targeted therapies and few candidates presently under clinical evaluation. Nearly all recurrent medulloblastomas and posterior fossa group A (PFA) ependymomas are located adjacent to and bathed by the cerebrospinal fluid, presenting an opportunity for locoregional therapy, bypassing the blood-brain barrier. We identify three cell-surface targets, EPHA2, HER2 and interleukin 13 receptor [alpha]2, expressed on medulloblastomas and ependymomas, but not expressed in the normal developing brain. We validate intrathecal delivery of EPHA2, HER2 and interleukin 13 receptor [alpha]2 chimeric antigen receptor T cells as an effective treatment for primary, metastatic and recurrent group 3 medulloblastoma and PFA ependymoma xenografts in mouse models. Finally, we demonstrate that administration of these chimeric antigen receptor T cells into the cerebrospinal fluid, alone or in combination with azacytidine, is a highly effective therapy for multiple metastatic mouse models of group 3 medulloblastoma and PFA ependymoma, thereby providing a rationale for clinical trials of these approaches in humans. Intraventricularly delivered monovalent and trivalent CAR T cells exhibit greater therapeutic efficacy as compared with intravenously delivered CAR T cells in medulloblastoma xenograft mouse models and show potency in ependymoma xenograft mouse models., Author(s): Laura K. Donovan [sup.1] [sup.2] , Alberto Delaidelli [sup.3] , Sujith K. Joseph [sup.4] [sup.5] , Kevin Bielamowicz [sup.4] [sup.5] , Kristen Fousek [sup.4] [sup.5] , Borja L. Holgado [...]

* Context.--Standards for pathology reporting of cancer are foundational to national and international benchmarking, epidemiology, and clinical trials, with international standards for pathology reporting of cancer being undertaken through the International Collaboration on Cancer Reporting (ICCR). Objective.--To develop standardized templates for brain tumor diagnostic pathology reporting. Design.--As a response to the 2016 updated 4th edition of the WHO (World Health Organization) Classification of Tumours of the Central Nervous System (2016 CNS WHO), an expert ICCR committee developed data sets to facilitate reporting of brain tumors that are classified histologically and molecularly by the 2016 CNS WHO; as such, this represents the first combined histologic and molecular ICCR data set, and required a novel approach with 3 highly related data sets that should be used in an integrated manner. Results.--The current article and accompanying ICCR Web site describe reporting data sets for central nervous system tumors in the hope that they provide easy-to-use and highly reproducible means to issue diagnostic reports in consort with the 2016 CNS WHO. Conclusions.--The consistent use of these templates will undoubtedly prove useful for patient care, clinical trials, epidemiologic studies, and monitoring of neuro-oncologic care around the world. (Arch Pathol Lab Med. 2020;144:196-206; doi: 10.5858/arpa.2018-0565-OA), The value of a structured or synoptic approach to cancer reporting, leading to improvement in the quality and completeness of pathology cancer reports, has been recognized through many studies (1-4) [...]

PurposeMyxopapillary ependymoma (MPE) is a distinct histologic variant of ependymoma arising commonly in the spinal cord. Despite an overall favorable prognosis, distant metastases, subarachnoid dissemination, and late recurrences have been reported. Currently, the only effective treatment for MPE is gross-total resection. We characterized the genomic and transcriptional landscape of spinal ependymomas in an effort to delineate the genetic basis of this disease and identify new leads for therapy.Experimental designGene expression profiling was performed on 35 spinal ependymomas, and copy number profiling was done on an overlapping cohort of 46 spinal ependymomas. Functional validation experiments were performed on tumor lysates consisting of assays measuring pyruvate kinase M activity (PKM), hexokinase activity (HK), and lactate production.ResultsAt a gene expression level, we demonstrate that spinal grade II and MPE are molecularly and biologically distinct. These are supported by specific copy number alterations occurring in each histologic variant. Pathway analysis revealed that MPE are characterized by increased cellular metabolism, associated with upregulation of HIF1α. These findings were validated by Western blot analysis demonstrating increased protein expression of HIF1α, HK2, PDK1, and phosphorylation of PDHE1A. Functional assays were performed on MPE lysates, which demonstrated decreased PKM activity, increased HK activity, and elevated lactate production.ConclusionsOur findings suggest that MPE may be driven by a Warburg metabolic phenotype. The key enzymes promoting the Warburg phenotype: HK2, PKM2, and PDK are targetable by small-molecule inhibitors/activators, and should be considered for evaluation in future clinical trials for MPE.

Replicative immortality is a hallmark of cancer cells governed by telomere maintenance. Approximately 90% of human cancers maintain their telomeres by activating telomerase, driven by the transcriptional upregulation of telomerase reverse transcriptase (TERT). Although TERT promoter mutations (TPMs) are a major cancer-associated genetic mechanism of TERT upregulation, many cancers exhibit TERT upregulation without TPMs. In this study, we describe the TERT hypermethylated oncological region (THOR), a 433-bp genomic region encompassing 52 CpG sites located immediately upstream of the TERT core promoter, as a cancer-associated epigenetic mechanism of TERT upregulation. Unmethylated THOR repressed TERT promoter activity regardless of TPM status, and hypermethylation of THOR counteracted this repressive function. THOR methylation analysis in 1,352 human tumors revealed frequent (>45%) cancer-associated DNA hypermethylation in 9 of 11 (82%) tumor types screened. Additionally, THOR hypermethylation, either independently or along with TPMs, accounted for how approximately 90% of human cancers can aberrantly activate telomerase. Thus, we propose that THOR hypermethylation is a prevalent telomerase-activating mechanism in cancer that can act independently of or in conjunction with TPMs, further supporting the utility of THOR hypermethylation as a prognostic biomarker., IntroductionReplicative immortality is an attribute of cancer cells governed by telomere maintenance (1). Telomeres are repetitive nucleoprotein structures that protect chromosomal ends and shorten after each replicative cycle, playing important [...]