An Immunohistochemical Study of Breast Cancer Brain Metastases: The Role of CD44 and AKT in the Prognosis.

Breast cancer is a major health burden, and up to one-third of patients with breast cancer develop brain metastases, which are linked to a very poor prognosis. Few biomarkers are available to predict the prognosis of patients with metastases. Assessment by immunohistochemistry may be used as a tool to predict the behavior of these tumors. A retrospective transversal study including 114 patients (diagnosed between 2000 and 2016) with breast cancer brain metastases was carried out using archival biological material from 114 patients with breast cancer brain metastases. Expression of CD44, HER2, ER, PR, CA9, PDL-1, CD133, ALDH1, PTEN, AKT, PI3K, and AR markers was assessed by immunohistochemistry. The overexpression of CD44 and AKT was associated with worse overall survival ( P =0.047 and P =0,034, respectively), on univariate analysis, in the cohort of parenchymal and bone metastases; the impact of AKT expression was also evident in the parenchymal cohort on uni ( P =0.021) and multivariate analysis ( P =0.027). The remaining markers did not exhibit a statistical correlation. Immunohistochemistry markers such as CD44 and AKT may have a prognostic impact on survival in patients with breast cancer brain metastases. The conjugation with other markers may help with the stratification of patients and therapy.

Resective Epilepsy Surgery and Respective Histopathological Diagnoses: A Retrospective Cohort Study.

INTRODUCTION: Over recent decades, brain resection for drug-resistant epilepsy has proven to be a valuable treatment option. The histopathological classification was of paramount value for patient management. The aims of this study were to characterize our resective epilepsy surgical series including the histopathological diagnoses and to understand the differences in clinical practice between two different periods of our epilepsy surgical programme. MATERIAL AND METHODS: We performed a retrospective cohort study, including patients with drug-resistant epilepsy that underwent resective surgery between 1997 and 2021 in the Coimbra University Hospital Centre. Histopathological diagnoses were classified into seven major conventional categories. For comparison purposes, the cohort was divided into two consecutive periods of 12 years. RESULTS: A total of 259 patients were included, from which 228 (88%) were adults at the time of surgery. The median disease duration prior to surgery was 14 (interquartile range 23) years. Fifty-five (21%) patients performed pre-surgical invasive work-up. The temporal lobe was the most frequently operated region (73%). Major and minor post-surgical complications were identified in 21 (8%) patients. A reduction in the number of antiepileptic drugs was possible in 96 (37%) patients after surgery. The most common histopathological diagnosis was hippocampal sclerosis, but among children it was long-term epilepsy associated tumour. Long-term epilepsy associated tumours, hippocampal sclerosis and vascular malformations had the best post-operative outcomes. Malformations of cortical development and glial scars had the worst outcomes. Regarding differences between the two periods, the absolute number of operated patients increased (119 versus 140), and the age at surgery was higher in the second period (p = 0.04). The number of malformations of cortical development increased (p = 0.01), but the number of other tumours (p = 0.01) and specimens with no lesion (p = 0.03) decreased in the same period. CONCLUSION: This study is in line with contemporaneous research, reinforcing the previous knowledge on the underlying structural aetiologies, clinical practice, and surgical outcomes over more than two decades of experience. Our data provide realistic expectations about epilepsy surgery and highlight the need for further improvements in diagnosis and treatment paradigm for people with chronic epilepsy.

Introdução: Nas últimas décadas, a cirurgia ressectiva demonstrou ser uma opção valiosa no tratamento da epilepsia farmacorresistente. A classificação histopatológica foi de grande importância na orientação do doente. Os objetivos deste estudo foram caracterizar a nossa série de cirurgia de epilepsia ressectiva incluindo os diagnósticos histopatológicos, e compreender as diferenças na prática clínica entre dois períodos diferentes do programa de cirurgia da epilepsia. Material e Métodos: Realizou-se um estudo de coorte retrospetivo, incluindo doentes com epilepsia farmacorresistente submetidos a cirurgia ressectiva entre 1997 e 2021 no Centro Hospitalar e Universitário de Coimbra. Os diagnósticos histopatológicos foram classificados em sete categorias. Para análise comparativa, a coorte foi dividida em dois períodos consecutivos de 12 anos. Resultados: Um total de 259 doentes foram incluídos, sendo 228 (88%) adultos aquando da cirurgia. A mediana da duração da doença antes da cirurgia foi de 14 (amplitude interquartil 23) anos. Cinquenta e cinco (21%) doentes realizaram investigação invasiva pré-cirúrgica. O lobo temporal foi a região mais frequentemente operada (73%). Complicações pós-cirúrgicas major e minor foram identificadas em 21 (8%) doentes. Uma redução no número de antiepiléticos foi observada em 96 (37%) doentes após a cirurgia. O diagnóstico histopatológico mais comum foi a esclerose do hipocampo, mas nas crianças foi o tumor associado a epilepsia de longa duração. Tumores associados a epilepsia de longa duração, esclerose do hipocampo e malformações vasculares tiveram os melhores resultados pós-operatórios. Malformações do desenvolvimento cortical e cicatrizes gliais tiveram os piores resultados. Relativamente às diferenças entre os dois períodos, o número absoluto de doentes operados aumentou (119 versus 140), e a idade aquando da cirurgia foi maior no segundo período (p = 0,04). O número de malformações do desenvolvimento cortical aumentou (p = 0,01), mas o número de outros tumores (p = 0,01) e amostras sem lesão (p = 0,03) diminuiu no mesmo período. Conclusão: Este estudo está de acordo com a literatura atual, reforçando o conhecimento prévio sobre as etiologias estruturais, prática clínica e resultados cirúrgicos ao longo de mais de duas décadas de experiência. Os dados analisados fornecem expectativas realistas sobre a cirurgia de epilepsia e destacam a necessidade de melhorias no paradigma de diagnóstico e tratamento destes doentes.

The Challenge of Somatic Variants in Focal Cortical Dysplasia.

Objective: The advent of next-generation sequencing (NGS) enabled the detection of low-level brain somatic variants in postsurgical tissue of focal cortical dysplasia (FCD). The genetic background of FCD Type I remains elusive, while the mammalian target of rapamycin (mTOR) pathway seems to have a relevant role in the pathogenesis of FCD Type II. Our goal was to uncover information on the molecular basis of FCD, performing whole genome sequencing (WGS) in postsurgical tissue to detect candidate brain-specific somatic variants, and evaluate their clinical significance. Design: WGS was performed using paired peripheral venous blood and postsurgical pathological brain deoxyribonucleic acid (DNA) samples. Libraries were prepared using the Roche KAPA HyperPrep polymerase chain reaction (PCR) free library preparation kit. Paired-end 150bp reads were generated on the Illumina NovaSeq platform. The FASTQ files were processed using the nf-core sarek pipeline (version 3.0) to call somatic variants, which were then annotated with ANNOVAR. A screening strategy was applied to obtain relevant variants. Results: Two female patients with drug-resistant epilepsy due to FCD who underwent surgical treatment were included. Regarding neuropathological diagnosis, one patient had FCD Type Ia and the other had FCD Type IIa. Five somatic nonsynonymous single nucleotide variants (SNVs) were detected using WGS, three in FCD Ia tissue (WDR24 p.Trp259Gly; MICAL1 p.Lys1036Arg; and KATNB1 p.Leu566Ile) and two in FCD IIa tissue (MATN4 p.Phe91Val and ANKRD6 p.His386Gln). All variants were predicted to be potentially pathogenic by at least two different tools. However, they were classified as variants of uncertain significance (VUS) according to the American College of Medical Genetics and Genomics (ACMG) criteria. Conclusion: Brain-specific somatic missense variants were identified by NGS in new candidate genes (WDR24, MICAL1, KATNB1, MATN4, and ANKRD6) using postsurgical FCD tissue, which may contribute to further understanding of the genetic background of FCD. All the reported genes were previously related to epilepsy and/or malformations of central nervous system (CNS) and cortical development. However, the pathogenicity assessment of these variants and, consequently, their impact on clinical practice still poses an important challenge.

The landscape of common genetic drivers and DNA methylation in low-grade (epilepsy-associated) neuroepithelial tumors: A review.

Low-grade neuroepithelial tumors (LNETs) represent an important group of central nervous system neoplasms, some of which may be associated to epilepsy. The concept of long-term epilepsy-associated tumors (LEATs) includes a heterogenous group of low-grade, cortically based tumors, associated to drug-resistant epilepsy, often requiring surgical treatment. LEATs entities can sometimes be poorly discriminated by histological features, precluding a confident classification in the absence of additional diagnostic tools. This study aimed to provide an updated review on the genomic findings and DNA methylation profiling advances in LNETs, including histological entities of LEATs. A comprehensive search strategy was conducted on PubMed, Embase, and Web of Science Core Collection. High-quality peer-reviewed original manuscripts and review articles with full-text in English, published between 2003 and 2022, were included. Results were screened based on titles and abstracts to determine suitability for inclusion, and when addressed the topic of the review was screened by full-text reading. Data extraction was performed through a qualitative content analysis approach. Most LNETs appear to be driven mainly by a single genomic abnormality and respective affected signaling pathway, including BRAF p.V600E mutations in ganglioglioma, FGFR1 abnormalities in dysembryoplastic neuroepithelial tumor, MYB alterations in angiocentric glioma, BRAF fusions in pilocytic astrocytoma, PRKCA fusions in papillary glioneuronal tumor, between others. However, these molecular alterations are not exclusive, with some overlap amongst different tumor histologies. Also, clustering analysis of DNA methylation profiles allowed the identification of biologically similar molecular groups that sometimes transcend conventional histopathological classification. The exciting developments on the molecular basis of these tumors reinforce the importance of an integrative histopathological and (epi)genetic classification, which can be translated into precision medicine approaches.

Cytogenomic Analysis of Long-Term Epilepsy-Associated Tumors Using an Array-Based CGH Strategy.

A palette of copy number changes in long-term epilepsy-associated tumors (LEATs) have been reported, but the data are heterogeneous. To better understand the molecular basis underlying the development of LEATs, we performed array-comparative genomic hybridization analysis to investigate chromosomal imbalances across the entire genome in 8 cases of LEATs. A high number of aberrations were found in 4 patients, among which deletions predominated. Both whole-chromosome and regional abnormalities were observed, including monosomy 19, deletion of 1p, deletions of 4p, 12p, and 22q, and gain of 20p. The common altered regions are located mainly on chromosomes 19 and 4p, identifying genes potentially involved in biological processes and cellular mechanisms related to tumorigenesis. Our study highlights new genomic alterations and reinforces others previously reported, offering new molecular insights that may help in diagnosis and therapeutic decision-making.

Neurological impact of eosinophilic granulomatosis with polyangiitis.

Nervous system (NS) affection may occur in Eosinophilic Granulomatosis with Polyangiitis (EGPA), but its clinical manifestations and pathophysiology are rarely described. Our aims are to characterize central and peripheral NS (CNS/PNS) involvement and compare biological markers in EGPA patients with and without neurological manifestations. Retrospective observational study, including EGPA patients with and without neurological manifestations. Demographics, clinical data, and immunological markers were analyzed. Descriptive and inferential statistics were performed. Sixteen patients were included; 11 (68.8%) of whom were male, with a mean age of 63.38 years; 8 with (Group 1) and 8 without (Group 2) neurological findings. Neurological impairment preceded EGPA diagnosis in 5 patients, and occurred during follow-up in 3 patients after a median of 4.0 years. CNS manifestations observed were stroke (n = 2), bilateral central retinal artery occlusion (n = 1), and compressive dorsal myelopathy due to extradural granulation tissue (n = 1). PNS manifestations were axonal polyneuropathy (n = 3), sensorineural hearing loss (n = 3), and multiplex mononeuropathy (n = 1). Two patients had both PNS and CNS involvement. There were no statistical differences regarding biological markers [eosinophil count, myeloperoxidase (MPO) antibodies titers] between the 2 groups. One patient from Group 1 was unresponsive to treatment and permanent neurological sequelae were observed in 7 cases. EGPA-related NS involvement can be heterogeneous and is responsible for long-term sequelae. In our sample, the main neurological scenarios were peripheral neuropathy, VIII cranial nerve neuropathy, ischemic lesions and compressive myelopathy. Patients with and without neurological manifestations did not differ in eosinophilic count and MPO titer.

Vasculitic peripheral neuropathy in deficiency of adenosine deaminase 2.

Deficiency of adenosine deaminase 2 (DADA2) is an autosomal recessive inflammatory vasculopathy characterized by systemic vasculitis, early-onset stroke and livedo racemosa. We report a family cohort of 3 patients with ADA2 compound heterozygous mutation p.[Thr360Ala] and [Gly383Ser]. Two of them had progressive involvement of the peripheral nervous system in the fourth decade, both after stroke. In one patient, clinical and neurophysiological studies showed progression of mononeuritis multiplex to chronic axonal sensorimotor polyneuropathy, nerve biopsy had features of small vessel vasculitic neuropathy, and muscle biopsy disclosed neurogenic atrophy with reinnervation. The second patient presented with progressive sensory symptoms of the lower limbs and chronic axonal sensorimotor polyneuropathy in nerve conduction studies. These two patients had absent plasma ADA2 activity. The third patient had no neurological affection despite low, but not absent, plasma ADA2 activity. Patients were started on a tumor necrosis factor (TNF) inhibitor, which has presumed benefits for the vasculitic phenotype of DADA2.

MiR-200c-based metabolic modulation in glioblastoma cells as a strategy to overcome tumor chemoresistance.

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor characterized by fast proliferation, high invasion and resistance to current standard treatment. The average survival rate post-diagnosis is 14.6 months, despite the aggressive standard post-surgery radiotherapy concomitant with chemotherapy with temozolomide (TMZ). Currently, efforts are being endowed to develop new and more efficient therapeutic approaches capable to overcome chemoresistance, inhibit tumor progression and improve overall patient survival rate. Abnormal microRNA (miRNA) expression has been correlated with chemoresistance, proliferation and resistance to apoptosis, which result from their master regulatory role of gene expression. Altered cell metabolism, favoring glycolysis, was identified as an emerging cancer hallmark and has been described in GB, thus offering a new target for innovative GB therapies. In this work, we hypothesized that a gene therapy-based strategy consisting of the overexpression of a miRNA downregulated in GB and predicted to target crucial metabolic enzymes might promote a shift of GB cell metabolism, decreasing the glycolytic dependence of tumor cells and contributing to their sensitization to chemotherapy with TMZ. The increase of miR-200c levels in DBTRG cells resulted in downregulation of messenger RNA of enzymes involved in bioenergetics pathways and impaired cell metabolism and mobility. In addition, miR-200c overexpression prior to DBTRG cell exposure to TMZ resulted in cell cycle arrest. Overall, our results show that miR-200c overexpression could offer a way to overcome chemoresistance developed by GB cells in response to current standard chemotherapy, providing an improvement to current GB standard treatment, with benefit for patient outcome.

Primary intramedullary spinal-cord lymphoma (PISCL): a rare entity with a challenging diagnosis.

Primary intramedullary spinal-cord lymphoma (PISCL) is a rare cause of myelopathy and constitutes only 1% of central nervous system lymphomas. Delay to diagnosis is common due to its rarity, its similarity to other causes of myelopathy and the difficulties in obtaining pathological diagnosis. We report a case of PISCL and discuss the challenges faced on diagnosis, namely the impact of corticosteroids on histological findings, the usefulness of MRI, positron-emission tomography/CT (PET/CT) and repeated lumbar punctures.

Downregulation of long non-protein coding RNA MVIH impairs glioblastoma cell proliferation and invasion through an miR-302a-dependent mechanism.

Glioblastoma (GB) is the most frequent and malignant type of brain tumor, for which no effective therapy exists. The high proliferative and invasive nature of GB, as well as its acquired resistance to chemotherapy, makes this type of cancer extremely lethal shortly after diagnosis. Long non-protein coding RNAs (lncRNA) are a class of regulatory RNAs whose levels can be dysregulated in the context of diseases, unbalancing several physiological processes. The lncRNA associated with microvascular invasion in hepatocellular carcinoma (lncRNA-MVIH), overexpressed in several cancers, was described to co-precipitate with phosphoglycerate kinase 1 (PGK1), preventing secretion of this enzyme to the extracellular environment and promoting cell migration and invasion. We hypothesized that, by silencing the expression of lncRNA-MVIH, the secretion of PGK1 would increase, reducing GB cell migration and invasion capabilities. We observed that lncRNA-MVIH silencing in human GB cells significantly decreased glycolysis, cell growth, migration, and invasion and sensitized GB cells to cediranib. However, no increase in extracellular PGK1 was observed as a consequence of lncRNA-MVIH silencing, and therefore, we investigated the possibility of a mechanism of miRNA sponge of lncRNA-MVIH being in place. We found that the levels of miR-302a loaded onto RISC increased in GB cells after lncRNA-MVIH silencing, with the consequent downregulation of several miR-302a molecular targets. Our findings suggest a new mechanism of action of lncRNA-MVIH as a sponge of miR-302a. We suggest that lncRNA-MVIH knockdown may be a promising strategy to address GB invasiveness and chemoresistance, holding potential towards its future application in a clinical context.

World Health Organization Grade III Meningiomas: A Retrospective Study at an Academic Medical Center.

BACKGROUND: Meningiomas are the most common primary brain tumors and are generally considered benign. However, a rare subgroup of meningiomas, classified as World Health Organization (WHO) grade III meningiomas, can show extremely aggressive behavior and high rates of recurrence. Despite ongoing research, data on the clinical outcome of this subgroup of meningiomas are still limited. METHODS: Medical records of patients with WHO grade III meningiomas diagnosed between 2000 and 2018 at the Coimbra University Hospital Center were retrospectively reviewed and several variables of interest and their relation to patients' survival were analyzed. RESULTS: Of the 26 patients included in the final analysis, 23 had anaplastic meningiomas, 2 had papillary meningiomas, and 1 had a rhabdoid meningioma. Median overall survival and median progression-free survival were 2.45 and 1.22 years, respectively. Overall survival at 1, 2 and 5 years was 73%, 57%, and 35%, respectively. Adjuvant radiotherapy correlated with improved survival for subtotally resected meningiomas but not for gross totally resected meningiomas. There was a trend toward improved overall survival with gross total resection versus subtotal resection, but this difference failed to reach statistical significance. CONCLUSIONS: This study provides insight into the clinical outcomes of WHO grade III meningiomas and suggests that adjuvant radiotherapy may not be beneficial for patients who underwent gross total resection. This rare subset of meningiomas still portends a devastating prognosis and the impact of extent of resection and adjuvant therapies in these patients needs further clarification.

Tumefactive demyelinating lesions spectrum disorders and the potential role of contemporary disease modifying treatments: a case report.

Marburg disease is a fulminant variant of multiple sclerosis (MS), in which the diagnosis may be particularly difficult and with high rates of mortality. We describe the case of a women with a clinical picture, radiographic features, and neuropathological findings consistent with the classical descriptions of Marburg disease. Initially, our patient did not improved with the acute phase treatments but later showed a good response to natalizumab (NTZ) treatment. This report highlights not only the utility of brain biopsy in the accurate diagnosis of this challenging condition but also the potential role of NTZ as an effective therapeutic option.

Laing early-onset distal myopathy with subsarcolemmal hyaline bodies caused by a novel variant in the MYH7 gene.

Myopathies caused by MYH7 gene mutations are clinically and pathologically heterogeneous and, until recently, difficult to diagnose. The availability of NGS panels for hereditary neuromuscular diseases changed our insight regarding their frequency and allowed a better perception of the different phenotypes and morphological abnormalities associated. We present a male Portuguese patient with the classical phenotype of Laing early-onset distal myopathy (MPD1) beginning at 6 years of age, very slowly progressive, and with a mild to moderate impact on daily life by the age of 56. Muscle biopsy showed a myopathic pattern with hyaline bodies and cores. The NGS panel for structural myopathies identified a novel missense heterozygous variant, c.T4652C (p.Leu1551Pro), in the exon 34 of the MYH7 gene.

Management and Outcome of Solitary Spinal Amyloidoma-A Systematic Literature Review.

BACKGROUND: Solitary spinal amyloidoma (SSA) is a rare and poorly characterized disease. There are few cases described, and the knowledge of this neoplasm is limited. A more accurate description of demographics, clinical findings, and outcomes may be useful for a better understanding of this pathology, as well as therapeutic intervention, adding value to the research of localized amyloidosis. METHODS: A systematic search was carried out from when registries began until February 2020. We also include a case diagnosed and treated in our department. Descriptive statistics were used to evaluate data, demographics, clinical findings, diagnostic modalities, therapeutics, and finally neurologic outcomes. The Kaplan-Meier method was used to assess overall survival and progression-free survival. RESULTS: The final cohort comprises 35 patients. The mean age at diagnosis was 61.97 years, and 68.60% of the patients were male. SSA developed more frequently in the thoracic spine (48.60%), followed by the cervical spine (17.10%). Intradural lesions were rare, and the average neoplastic score for spinal instability was 9.5 points. The most common symptoms were impaired motor function (74.29%) and axial back pain (65.70%). After surgery, neurologic recovery was reported in 82.90% of cases. Mean progression-free survival and mean overall survival were 47.26 and 156.66 months. CONCLUSIONS: SSA is a rare subgroup of localized amyloidosis, usually being diagnosed in male patients between the sixth and eighth decades. The gold standard treatment seems to be surgical resection. SSA patients have excellent long-term survival and a low rate of local recurrence.

Primary spinal epidural lymphoma: a rare entity with an ambiguous management.

Lymphomas are malignant lymphoid tumours arising from lymphocytic cells. They usually develop in the lymphoid tissues and can spread to other organs; however, primary extra-nodal locations such as the spinal epidural space are less common. The authors report the case of a primary diffuse large B-cell lymphoma of the thoracic spine in a 65-year-old man, who presented to the emergency department with signs of upper motor neuron lesion. The patient underwent surgery in order to decompress the spinal cord. The treatment was concluded with six cycles of chemotherapy with methotrexate, rituximab, cyclophosphamide, vincristine and prednisone followed by radiotherapy. At the 24-month follow-up, no signs of epidural lesion or bone contrast enhancement were observed in thoracic spine MRI. Surgical decompression is recommended in patients with signs of spinal cord injury in order to prevent irreversible neurological damage and is related to high rates of disease-free survival.

Genomic and Epigenetic Advances in Focal Cortical Dysplasia Types I and II: A Scoping Review.

Introduction: Focal cortical dysplasias (FCDs) are a group of malformations of cortical development that constitute a common cause of drug-resistant epilepsy, often subjected to neurosurgery, with a suboptimal long-term outcome. The past few years have witnessed a dramatic leap in our understanding of the molecular basis of FCD. This study aimed to provide an updated review on the genomic and epigenetic advances underlying FCD etiology, to understand a genotype-phenotype correlation and identify priorities to lead future translational research. Methods: A scoping review of the literature was conducted, according to previously described methods. A comprehensive search strategy was applied in PubMed, Embase, and Web of Science from inception to 07 May 2020. References were screened based on title and abstract, and posteriorly full-text articles were assessed for inclusion according to eligibility criteria. Studies with novel gene variants or epigenetic regulatory mechanisms in patients that underwent epilepsy surgery, with histopathological diagnosis of FCD type I or II according to Palmini's or the ILAE classification system, were included. Data were extracted and summarized for an overview of evidence. Results: Of 1,156 candidate papers, 39 met the study criteria and were included in this review. The advent of next-generation sequencing enabled the detection in resected FCD tissue of low-level brain somatic mutations that occurred during embryonic corticogenesis. The mammalian target of rapamycin (mTOR) signaling pathway, involved in neuronal growth and migration, is the key player in the pathogenesis of FCD II. Somatic gain-of-function variants in MTOR and its activators as well as germline, somatic, and second-hit mosaic loss-of-function variants in its related repressors have been reported. However, the genetic background of FCD type I remains elusive, with a pleomorphic repertoire of genes affected. DNA methylation and microRNAs were the two epigenetic mechanisms that proved to have a functional role in FCD and may represent molecular biomarkers. Conclusion: Further research into the possible pathogenic causes of both FCD subtypes is required, incorporating single-cell DNA/RNA sequencing as well as methylome and proteomic analysis. The collected data call for an integrated clinicopathologic and molecular genetic diagnosis in current practice not only to improve diagnostic accuracy but also to guide the development of future targeted treatments.

Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course.

The "isomorphic subtype of diffuse astrocytoma" was identified histologically in 2004 as a supratentorial, highly differentiated glioma with low cellularity, low proliferation and focal diffuse brain infiltration. Patients typically had seizures since childhood and all were operated on as adults. To define the position of these lesions among brain tumours, we histologically, molecularly and clinically analysed 26 histologically prototypical isomorphic diffuse gliomas. Immunohistochemically, they were GFAP-positive, MAP2-, OLIG2- and CD34-negative, nuclear ATRX-expression was retained and proliferation was low. All 24 cases sequenced were IDH-wildtype. In cluster analyses of DNA methylation data, isomorphic diffuse gliomas formed a group clearly distinct from other glial/glio-neuronal brain tumours and normal hemispheric tissue, most closely related to paediatric MYB/MYBL1-altered diffuse astrocytomas and angiocentric gliomas. Half of the isomorphic diffuse gliomas had copy number alterations of MYBL1 or MYB (13/25, 52%). Gene fusions of MYBL1 or MYB with various gene partners were identified in 11/22 (50%) and were associated with an increased RNA-expression of the respective MYB-family gene. Integrating copy number alterations and available RNA sequencing data, 20/26 (77%) of isomorphic diffuse gliomas demonstrated MYBL1 (54%) or MYB (23%) alterations. Clinically, 89% of patients were seizure-free after surgery and all had a good outcome. In summary, we here define a distinct benign tumour class belonging to the family of MYB/MYBL1-altered gliomas. Isomorphic diffuse glioma occurs both in children and adults, has a concise morphology, frequent MYBL1 and MYB alterations and a specific DNA methylation profile. As an exclusively histological diagnosis may be very challenging and as paediatric MYB/MYBL1-altered diffuse astrocytomas may have the same gene fusions, we consider DNA methylation profiling very helpful for their identification.

Subacute inflammatory myopathy associated with papillary cancer of the thyroid gland.

Inflammatory myopathies comprise a group of rare autoimmune muscle diseases characterized by a variable degree of muscle weakness, elevated creatine kinase levels and necrotic fibres associated with invading inflammatory cells at histologic examination. Although there are several reports about their relationship with malignancy, association with papillary cancer of the thyroid gland is extremely rare. We present a case of a female patientdiagnosed withinflammatory myopathy and apapillary cancer of the thyroid gland, with a remarkable clinical improvement after thyroid cancer surgery and radioactive iodine treatment, supporting a correlation between the two conditions.

MiR-144 overexpression as a promising therapeutic strategy to overcome glioblastoma cell invasiveness and resistance to chemotherapy.

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor, characterized by fast proliferation, high invasion, and resistance to current standard treatment. The average survival rate post-diagnosis is only of 14.6 months, despite the aggressive standard post-surgery treatment approaches of radiotherapy concomitant with chemotherapy with temozolomide. Altered cell metabolism has been identified as an emerging cancer hallmark, including in GB, thus offering a new target for cancer therapies. On the other hand, abnormal expression levels of miRNAs, key regulators of multiple molecular pathways, have been correlated with pathological manifestations of cancer, such as chemoresistance, proliferation, and resistance to apoptosis. In this work, we hypothesized that gene therapy based on modulation of a miRNA with aberrant expression in GB and predicted to target crucial metabolic enzymes might impair tumor cell metabolism. We found that the increase of miR-144 levels, shown to be downregulated in U87 and DBTRG human GB cell lines, as well as in GB tumor samples, promoted the downregulation of mRNA of enzymes involved in bioenergetic pathways, with consequent alterations in cell metabolism, impairment of migratory capacity, and sensitization of DBTRG cells to a chemotherapeutic drug, the dichloroacetate (DCA). Taken together, our findings provide evidence that the miR-144 plus DCA combined therapy holds promise to overcome GB-acquired chemoresistance, therefore deserving to be explored toward its potential application as a complementary therapeutic approach to the current treatment options for this type of brain tumor.