Search

Ocular adnexal sebaceous carcinoma (SebCA) represents one of the most clinically problematic periocular tumors, often requiring aggressive surgical resection. The pathobiology of this tumor remains poorly understood, and few models exist that are suitable for preclinical testing. The aim of this study was to establish new cell lines to serve as models for pathobiological and drug testing. With patient consent, freshly resected tumor tissue was cultured using conditional reprogramming cell conditions. Standard techniques were used to characterize the cell lines in terms of overall growth, clonogenicity, apoptosis, and differentiation in vitro. Additional analyses including Western blotting, short tandem repeat (STR) profiling, and next-generation sequencing (NGS) were performed. Drug screening using mitomycin-C (MMC), 5-fluorouricil (5-FU), and 6-Diazo-5-oxo-L-norleucine (DON) were performed. JHH-SebCA01, JHH-SebCA02, and JHH-SebCA03 cell lines were established from two women and one man undergoing surgical resection of eyelid tumors. At passage 15, they each showed a doubling time of two to three days, and all could form colonies in anchorage-dependent conditions, but not in soft agar. The cells contained cytoplasmic vacuoles consistent with sebaceous differentiation, and adipophilin protein was present in all three lines. STR profiling confirmed that all lines were derived from their respective patients. NGS of the primary tumors and their matched cell lines identified numerous shared mutations, including alterations similar to those previously described in SebCA. Treatment with MMC or 5-FU resulted in dose-dependent growth inhibition and the induction of both apoptosis and differentiation. MYC protein was abundant in all three lines, and the glutamine metabolism inhibitor DON, previously shown to target high MYC tumors, slowed the growth of all our SebCA models. Ocular adnexal SebCA cell lines can be established using conditional reprogramming cell conditions, and our three new models are useful for testing therapies and interrogating the functional role of MYC and other possible molecular drivers. Current topical chemotherapies promote both apoptosis and differentiation in SebCA cells, and these tumors appear sensitive to inhibition or MYC-associated metabolic changes. [ABSTRACT FROM AUTHOR]

Medulloblastoma, the most common malignant pediatric brain tumor, is classified into four main molecular subgroups, but group 3 and group 4 tumors are difficult to subclassify and have a poor prognosis. Rapid point-of-care diagnostic and prognostic assays are needed to improve medulloblastoma risk stratification and management. N6-methyladenosine (m6A) is a common RNA modification and long non-coding RNAs (lncRNAs) play a central role in tumor progression, but their impact on gene expression and associated clinical outcomes in medulloblastoma are unknown. Here we analyzed 469 medulloblastoma tumor transcriptomes to identify lncRNAs co-expressed with m6A regulators. Using LASSO-Cox analysis, we identified a five-gene m6A-associated lncRNA signature (M6LSig) significantly associated with overall survival, which was combined in a prognostic clinical nomogram. Using expression of the 67 m6A-associated lncRNAs, a subgroup classification model was generated using the XGBoost machine learning algorithm, which had a classification accuracy > 90%, including for group 3 and 4 samples. All M6LSig genes were significantly correlated with at least one immune cell type abundance in the tumor microenvironment, and the risk score was positively correlated with CD4+ naïve T cell abundance and negatively correlated with follicular helper T cells and eosinophils. Knockdown of key m6A writer genes METTL3 and METTL14 in a group 3 medulloblastoma cell line (D425-Med) decreased cell proliferation and upregulated many M6LSig genes identified in our in silico analysis, suggesting that the signature genes are functional in medulloblastoma. This study highlights a crucial role for m6A-dependent lncRNAs in medulloblastoma prognosis and immune responses and provides the foundation for practical clinical tools that can be rapidly deployed in clinical settings. [ABSTRACT FROM AUTHOR]

Simple Summary: Immune checkpoint blockade has shown remarkable efficacy across various cancers but has failed to improve outcomes in patients with relapsed medulloblastoma (MB). While it is thought that the cold, immunosuppressive tumor microenvironment of MB accounts for this poor efficacy, the precise mechanisms contributing to immune suppression in this context remain unclear. In this study, we explore the immune landscape of MB using a previously unexplored syngeneic mouse model. Our study demonstrates that this model faithfully recapitulates the cold, immunosuppressive tumor microenvironment observed in human disease. Importantly, our research uncovers mechanisms employed by myeloid cells and tumor cells to evade immune detection while highlighting the therapeutic potential of targeting V-domain Ig Suppressor of T-cell Activation (VISTA), a novel inhibitory immune checkpoint, to enhance anti-tumor immunity. Background: Relapsed medulloblastoma (MB) poses a significant therapeutic challenge due to its highly immunosuppressive tumor microenvironment. Immune checkpoint inhibitors (ICIs) have struggled to mitigate this challenge, largely due to low T-cell infiltration and minimal PD-L1 expression. Identifying the mechanisms driving low T-cell infiltration is crucial for developing more effective immunotherapies. Methods: We utilize a syngeneic mouse model to investigate the tumor immune microenvironment of MB and compare our findings to transcriptomic and proteomic data from human MB. Results: Flow cytometry reveals a notable presence of CD45hi/CD11bhi macrophage-like and CD45int/CD11bint microglia-like tumor-associated macrophages (TAMs), alongside regulatory T-cells (Tregs), expressing high levels of the inhibitory checkpoint molecule VISTA. Compared to sham control mice, the CD45hi/CD11bhi compartment significantly expands in tumor-bearing mice and exhibits a myeloid-specific signature composed of VISTA, CD80, PD-L1, CTLA-4, MHCII, CD40, and CD68. These findings are corroborated by proteomic and transcriptomic analyses of human MB samples. Immunohistochemistry highlights an abundance of VISTA-expressing myeloid cells clustering at the tumor–cerebellar border, while T-cells are scarce and express FOXP3. Additionally, tumor cells exhibit immunosuppressive properties, inhibiting CD4 T-cell proliferation in vitro. Identification of VISTA's binding partner, VSIG8, on tumor cells, and its correlation with increased VISTA expression in human transcriptomic analyses suggests a potential therapeutic target. Conclusions: This study underscores the multifaceted mechanisms of immune evasion in MB and highlights the therapeutic potential of targeting the VISTA–VSIG axis to enhance anti-tumor responses. [ABSTRACT FROM AUTHOR]

NF2-related schwannomatosis (NF2) is a rare autosomal-dominant genetic disorder characterized by bilateral vestibular schwannomas and multiple meningiomas. This case report presents the extremely rare occurrence of an anaplastic meningioma in a 12-year-old male with previously undiagnosed NF2. The patient presented with a history of abdominal pain and episodic emesis, gait unsteadiness, right upper and lower extremity weakness, and facial weakness. He had sensorineural hearing loss and wore bilateral hearing aids. MR imaging revealed a sizable left frontoparietal, dural-based meningioma with heterogeneous enhancement with mass effect on the brain and midline shift. Multiple additional CNS lesions were noted including a homogenous lesion at the level of T5 indicative of compression of the spinal cord. The patient underwent a frontotemporoparietal craniotomy for the removal of his large dural-based meningioma, utilizing neuronavigation and transdural ultrasonography for precise en bloc resection of the mass. Histopathology revealed an anaplastic meningioma, WHO grade 3, characterized by brisk mitotic activity, small-cell changes, high Ki-67 proliferation rate, and significant loss of P16. We report an anaplastic meningioma associated with an underlying diagnosis of NF2 for which we describe clinical and histopathological features. [ABSTRACT FROM AUTHOR]

This article, published in Acta Neuropathologica, explores the role of ASXL1 mutations in central nervous system (CNS) tumors. ASXL1 is an epigenetic modifier that represses target genes through various mechanisms. The study found that ASXL1 mutations were present in various types of CNS tumors, including glioblastoma, oligodendroglioma, medulloblastoma, and ependymoma. These mutations were associated with reduced levels of H3K27me3, a histone modification involved in gene regulation. The authors suggest that ASXL1 inactivation contributes to CNS tumorigenesis through dysregulation of epigenetic processes. Further research is needed to understand the specific mechanisms and potential therapeutic implications of ASXL1 mutations in CNS tumors. [Extracted from the article]

Purpose Corneal biomechanical failure is the hallmark of keratoconus (KC); however, the cause of this failure remains elusive. Collagen type XII (COL12A1), which localises to Bowman's layer (BL), is thought to function in stress-bearing areas, such as BL. Given the putative protective role of COL12A1 in biomechanical stability, this study aims to characterise COL12A1 expression in all corneal layers involved in KC. Methods TaqMan quantitative PCR was performed on 31 corneal epithelium samples of progressive KC and myopic control eyes. Tissue microarrays were constructed using full-thickness corneas from 61 KC cases during keratoplasty and 18 non-KC autopsy eyes and stained with an antibody specific to COL12A1. Additionally, COL12A1 was knocked out in vitro in immortalised HEK293 cells. Results COL12A1 expression was reduced at transcript levels in KC epithelium compared with controls (ratio: 0.58, p<0.03). Immunohistochemical studies demonstrated that COL12A1 protein expression in BL was undetectable, with reduced expression in KC epithelium, basement membrane and stroma. Conclusions The apparent absence of COL12A1 in KC BL, together with the functional importance that COL12A1 is thought to have in stress bearing areas, suggests that COL12A1 may play a role in the pathogenesis of KC. Further studies are necessary to investigate the mechanisms that lead to COL12A1 dysregulation in KC. [ABSTRACT FROM AUTHOR]

It has previously been reported that antioxidant vitamins can help reduce the risk of vision loss associated with progression to advanced age-related macular degeneration (AMD), a leading cause of visual impairment among the elderly. Nonetheless, how oxidative stress contributes to the development of choroidal neovascularization (CNV) in some AMD patients and geographic atrophy (GA) in others is poorly understood. Here, we provide evidence demonstrating that oxidative stress cooperates with hypoxia to synergistically stimulate the accumulation of hypoxia-inducible factor (HIF)-1a in the retinal pigment epithelium (RPE), resulting in increased expression of the HIF-1-dependent angiogenic mediators that promote CNV. HIF-1 inhibition blocked the expression of these angiogenic mediators and prevented CNV development in an animal model of ocular oxidative stress, demonstrating the pathological role of HIF-1 in response to oxidative stress stimulation in neovascular AMD. While human-induced pluripotent stem cell (hiPSC)-derived RPE monolayers exposed to chemical oxidants resulted in disorganization and disruption of their normal architecture, RPE cells proved remarkably resistant to oxidative stress. Conversely, equivalent doses of chemical oxidants resulted in apoptosis of hiPSC-derived retinal photoreceptors. Pharmacologic inhibition of HIF-1 in the mouse retina enhanced--while HIF-1 augmentation reduced--photoreceptor apoptosis in two mouse models for oxidative stress, consistent with a protective role for HIF-1 in photoreceptors in patients with advanced dry AMD. Collectively, these results suggest that in patients with AMD, increased expression of HIF-1a in RPE exposed to oxidative stress promotes the development of CNV, but inadequate HIF-1a expression in photoreceptors contributes to the development of GA. [ABSTRACT FROM AUTHOR]

This article discusses the case of a 46-year-old woman who presented with new onset seizures. Magnetic resonance imaging (MRI) revealed a mass in the right posterior frontal lobe. The patient underwent surgery for resection of the mass, but follow-up imaging showed tumor recurrence. Histologic analysis revealed a glial neoplasm with certain molecular alterations. The case highlights the challenges of classifying central nervous system tumors based on molecular profiling and emphasizes the need for an integrated approach to diagnosis. [Extracted from the article]

Chemical exchange saturation transfer (CEST) imaging is an important molecular magnetic resonance imaging technique that can image numerous low‐concentration biomolecules with water‐exchangeable protons (such as cellular proteins) and tissue pH. CEST, or more specially amide proton transfer‐weighted imaging, has been widely used for the detection, diagnosis, and response assessment of brain tumors, and its feasibility in identifying molecular markers in gliomas has also been explored in recent years. In this paper, after briefing on the basic principles and quantification methods of CEST imaging, we review its early applications in identifying isocitrate dehydrogenase mutation status, MGMT methylation status, 1p/19q deletion status, and H3K27M mutation status in gliomas. Finally, we discuss the limitations or weaknesses in these studies. [ABSTRACT FROM AUTHOR]

Giant cell arteritis (GCA) is often categorised as "active" or "healed" on temporal artery biopsy (TAB). The purpose of this study was to compare the initial clinical presentation of patients with GCA according to active versus healed arteritis on TAB. A retrospective chart review was performed for patients with biopsy-proven GCA (BP-GCA) at a single academic medical institution from a previously reported cohort. The arteritis on TAB was categorised as "active" or "healed" based on the pathological reports. Demographic information, clinical presentation, past medical history, and test results were collected from the date of TAB. These baseline characteristics were entered into the GCA Risk Calculator. Of 85 patients with BP-GCA, 80% had active and 20% had healed disease according to histopathology. A higher percentage of those with active arteritis had ischaemic optic neuropathy (ION) (36% versus 6%, p =.03), elevated erythrocyte sedimentation rates (92% versus 63%, p =.01), elevated C-reactive protein levels (79% versus 46%, p =.049), GCA risk score > 7.5% (99% sensitivity, 100% versus 71%, p <.001), higher mean GCA risk calculator scores (neural network p =.001; logistic regression p =.002). Patients with healed arteritis were less likely to have visual manifestations than the active arteritis group (38% versus 71%, p =.04). Patients with active vasculitis on biopsy had higher rates of ION and elevated inflammatory markers, as well as higher predictive scores from the GCA risk calculator. Further research is needed regarding correlation of biopsy findings and risk of complications or relapses. [ABSTRACT FROM AUTHOR]

Medulloblastoma (MB) develops through various genetic, epigenetic, and non-coding (nc) RNA-related mechanisms, but the roles played by ncRNAs, particularly circular RNAs (circRNAs), remain poorly defined. CircRNAs are increasingly recognized as stable non-coding RNA therapeutic targets in many cancers, but little is known about their function in MBs. To determine medulloblastoma subgroup-specific circRNAs, publicly available RNA sequencing (RNA-seq) data from 175 MB patients were interrogated to identify circRNAs that differentiate between MB subgroups. circ_63706 was identified as sonic hedgehog (SHH) group-specific, with its expression confirmed by RNA-FISH analysis in clinical tissue samples. The oncogenic function of circ_63706 was characterized in vitro and in vivo. Further, circ_63706-depleted cells were subjected to RNA-seq and lipid profiling to identify its molecular function. Finally, we mapped the circ_63706 secondary structure using an advanced random forest classification model and modeled a 3D structure to identify its interacting miRNA partner molecules. Circ_63706 regulates independently of the host coding gene pericentrin (PCNT), and its expression is specific to the SHH subgroup. circ_63706-deleted cells implanted into mice produced smaller tumors, and mice lived longer than parental cell implants. At the molecular level, circ_63706-deleted cells elevated total ceramide and oxidized lipids and reduced total triglyceride. Our study implicates a novel oncogenic circular RNA in the SHH medulloblastoma subgroup and establishes its molecular function and potential as a future therapeutic target. [ABSTRACT FROM AUTHOR]

BRAF mutations are a significant driver of disease in pediatric low-grade glioma, but the implications of BRAF alterations on the clinical course and treatment response in adult glioma remain unclear. Here, we characterize a multi-institutional cohort of more than 300 patients (>200 adults) with BRAF-mutated glioma using clinical, pathological/molecular, and outcome data. We observed that adult and pediatric BRAF-mutant gliomas harbor distinct clinical and molecular features, with a higher prevalence of BRAFV600E (Class I) and BRAF fusions in pediatric tumors. BRAFV600E alterations were associated with improved survival in adults with glioma overall, though not in glioblastoma. Other genomic alterations observed within functional classes were consistent with the putative roles of those BRAF mutation classes in glioma pathogenesis. In our adult cohort, BRAFV600E alterations conferred sensitivity to targeted therapies. Overall, this large cohort of BRAF-altered adult gliomas demonstrates a broad range of molecular alterations with implications for treatment sensitivity and survival. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the value of amide proton transfer‐weighted (APTw) MRI radiomic features for the differentiation of tumor recurrence from treatment effect in malignant gliomas. Eighty‐six patients who had suspected tumor recurrence after completion of chemoradiation or radiotherapy, and who had APTw‐MRI data acquired at 3 T, were retrospectively analyzed. Using a fluid‐attenuated inversion recovery (FLAIR) image‐based mask, radiomics analysis was applied to the processed APTw and structural MR images. A chi‐square automatic interaction detector decision tree was used for classification analysis. Models with and without APTw features were built using the same strategy. Tenfold cross‐validation was applied to obtain the overall classification performance of each model. Sixty patients were confirmed as having tumor recurrence, and the remainder were confirmed as having treatment effect, at median time points of 190 and 171 days after therapy, respectively. There were 525 radiomic features extracted from each of the processed APTw and structural MR images. Based on these, the APTw‐based model yielded the highest accuracy (86.0%) for the differentiation of tumor recurrence from treatment effect, compared with 74.4%, 76.7%, 83.7%, and 76.7% for T1w, T2w, FLAIR, and Gd‐T1w, respectively. Model classification accuracy was 82.6% when using the combined structural MR images (T1w, T2w, FLAIR, Gd‐T1w), and increased to 89.5% when using these structural plus APTw images. The corresponding sensitivity and specificity were 85.0% and 76.9% for the combination of structural MR images, and 85.0% and 100% after adding APTw image features. Adding APTw‐based radiomic features increased MRI accuracy in the assessment of the treatment response in post‐treatment malignant gliomas. [ABSTRACT FROM AUTHOR]

A 61-year-old man underwent left medial wall and floor fracture repair with a Suprafoil® implant. He had postoperative orbital congestion and lower eyelid swelling that persisted for over seven weeks. Examination demonstrated hyperglobus with supraduction, infraduction, and adduction deficits. Imaging revealed a 3.7 × 3.6 × 2.6 cm isodensity along the implant, thought to be hematoma. The patient elected to pursue exploration and possible drainage. Intraoperatively, there was no hematoma; rather, we found a fibroinflammatory rind along the periorbita surrounding the implant. This was biopsied, and the implant was removed, as the fractures had sufficiently healed. Pathology showed dense fibroconnective tissue with associated inflammation. The patient completed a steroid taper with improvement in all symptoms and resolution of diplopia. To our knowledge, this is the first reported case of such a prominent orbital inflammatory reaction to nylon foil, a departure from the delayed hematic cysts typically associated with these implants. [ABSTRACT FROM AUTHOR]

Recent advancements in understanding the biology of glioblastomas (GBM) and increasing adoption of genomic sequencing in oncology practice have led to the discovery of several targetable mutations in these cancers. Among them, the BRAF V600E mutation can be found in approximately 3% of GBM. Despite the aggressive nature of GBM, metastatic disease is rarely observed. While there are growing data utilizing BRAF-targeting strategies in patients with GBM, data examining their efficacy in cases of metastatic GBM are lacking. We present the case of a 46-year-old female with GBM, isocitrate dehydrogenase (IDH)-wildtype and O6-methylguanine-DNA methyltransferase promoter (MGMT) unmethylated, BRAF V600E-mutant, and MYC amplified with extra-central nervous system spread to the spine and lung. Four months after completion of treatment with standard chemoradiation and temozolomide, the patient developed severe back pain, leading to the eventual discovery of her metastatic disease. Based on the presence of the BRAF V600E mutation, the patient was treated with and achieved an intracranial and systemic response to combination BRAF-MEK targeted inhibition for 9 months before evidence of progression. [ABSTRACT FROM AUTHOR]

Simple Summary: Our study contributes to understanding the therapeutic effects of cordycepin in cancer. First, we find that the anticancer effects of cordycepin alone are only seen in tumor cell lines with low ADA expression or activity. This was true in multiple tumor types and may be applied as a predictive biomarker for the future treatment of patients. Second, we show that inhibition of ADA enhances cordycepin's anticancer effects by blocking its conversion to 3′-deoxyinosine in uveal melanoma and several other tumors. This raises the possibility of clinical combination treatments with cordycepin and ADA inhibitors, and our data suggest that much lower doses of cordycepin are possible in this context. Third, we identified a new mechanism of action for cordycepin: inhibiting the function of a protein known as Hsp90. Alterations in metabolism and energy production are increasingly being recognized as important drivers of neoplasia, raising the possibility that metabolic analogs could disrupt oncogenic pathways. 3′-deoxyadenosine, also known as cordycepin, is an adenosine analog that inhibits the growth of several types of cancer. However, the effects of cordycepin have only been examined in a limited number of tumor types, and its mechanism of action is poorly understood. We found that cordycepin slows the growth and promotes apoptosis in uveal melanoma, as well as a range of other hard-to-treat malignancies, including retinoblastoma, atypical teratoid rhabdoid tumors, and diffuse midline gliomas. Interestingly, these effects were dependent on low adenosine deaminase (ADA) expression or activity. Inhibition of ADA using either siRNA or pharmacologic approaches sensitized tumors with higher ADA to cordycepin in vitro and in vivo, with increased apoptosis, reduced clonogenic capacity, and slower migration of neoplastic cells. Our studies suggest that ADA is both a biomarker predicting response to cordycepin and a target for combination therapy. We also describe a novel mechanism of action for cordycepin: competition with adenosine triphosphate (ATP) in binding to Hsp90, resulting in impaired processing of oncogenic Hsp90 client proteins. [ABSTRACT FROM AUTHOR]

In-situ hybridization provides a convenient and reliable method to detect human papillomavirus (HPV) infection in formalin-fixed paraffin-embedded tissue. Cases of conjunctival papillomas, conjunctival intraepithelial neoplasia (CIN), conjunctival carcinoma in situ (cCIS), and invasive squamous cell carcinoma (SCC), in which low-risk (LR) and/or high-risk (HR) HPV types were evaluated by RNA or DNA in-situ hybridization, were retrospectively identified. LR HPV types were frequently detected in conjunctival papillomas (25/30, 83%), including 17/18 (94%) with RNA probes, compared to 8/12 (75%) with DNA probes. None of the CIN/cCIS or SCC cases were positive for LR HPV by either method. HR HPV was detected by RNA in-situ hybridization in 1/16 (6%) of CIN/cCIS cases and 2/4 (50%) of SCC cases, while DNA in-situ hybridization failed to detect HPV infection in any of the CIN/cCIS lesions. Reactive atypia and dysplasia observed in papillomas was generally associated with the detection of LR HPV types. Collectively, our findings indicate RNA in-situ hybridization may provide a high-sensitivity approach for identifying HPV infection in squamous lesions of the conjunctiva and facilitate the distinction between reactive atypia and true dysplasia. There was no clear association between HPV infection and atopy in papillomas or dysplastic lesions. [ABSTRACT FROM AUTHOR]

Simple Summary: Tumors of the brain and nerves develop frequently in patients with neurofibromatosis type 1. Many are benign growths, such as pilocytic astrocytomas in the brain and neurofibromas in the nerves. However, in some patients, the tumors become malignant and may cause local damage, disseminate to distant sites and result in death. We studied changes in the levels of chromatin proteins and changes in telomeres, in cells obtained from mouse gliomas that are deficient in neurofibromin as well as excess brain and nerve tumor tissue from patients with neurofibromatosis type 1 or sporadic tumors lacking neurofibromin expression. A decrease in the levels of these proteins in experimental cell lines resulted in susceptibility to a class of specific drugs knowns as ATR inhibitors, which may represent a specific vulnerability of these tumor subgroups. We expect our data to provide the required rationale for the development of more accurate animal models to study neurofibromatosis, as well as specific molecularly based drugs for treatment as alternatives to the current, often devastating approaches of surgery, radiation, and chemotherapy. Subsets of Neurofibromatosis Type 1 (NF1)-associated solid tumors have been shown to display high frequencies of ATRX mutations and the presence of alternative lengthening of telomeres (ALT). We studied the phenotype of combined NF1 and ATRX deficiency in malignant solid tumors. Cell lines derived from NF1-deficient sporadic glioblastomas (U251, SF188), an NF1-associated ATRX mutant glioblastoma cell line (JHH-NF1-GBM1), an NF1-derived sarcoma cell line (JHH-CRC65), and two NF1-deficient MPNST cell lines (ST88-14, NF90.8) were utilized. Cancer cells were treated with ATR inhibitors, with or without a MEK inhibitor or temozolomide. In contrast to the glioma cell line SF188, combined ATRX knockout (KO) and TERC KO led to ALT-like properties and sensitized U251 glioma cells to ATR inhibition in vitro and in vivo. In addition, ATR inhibitors sensitized U251 cells to temozolomide, but not MEK inhibition, irrespective of ATRX level manipulation; whereas, the JHH-NF1-GBM1 cell line demonstrated sensitivity to ATR inhibition, but not temozolomide. Similar effects were noted using the MPNST cell line NF90.8 after combined ATRX knockdown and TERC KO; however, not in ST88-14. Taken together, our study supports the feasibility of targeting the ATR pathway in subsets of NF1-deficient and associated tumors. [ABSTRACT FROM AUTHOR]

Medulloblastoma (MB) is the most common malignant brain tumor in children. There remains an unmet need for diagnostics to sensitively detect the disease, particularly recurrences. Cerebrospinal fluid (CSF) provides a window into the central nervous system, and liquid biopsy of CSF could provide a relatively non-invasive means for disease diagnosis. There has yet to be an integrated analysis of the transcriptomic, metabolomic, and lipidomic changes occurring in the CSF of children with MB. CSF samples from patients with (n = 40) or without (n = 11; no cancer) MB were subjected to RNA-sequencing and high-resolution mass spectrometry to identify RNA, metabolite, and lipid profiles. Differentially expressed transcripts, metabolites, and lipids were identified and their biological significance assessed by pathway analysis. The DIABLO multivariate analysis package (R package mixOmics) was used to integrate the molecular changes characterizing the CSF of MB patients. Differentially expressed transcripts, metabolites, and lipids in CSF were discriminatory for the presence of MB but not the exact molecular subtype. One hundred and ten genes and ten circular RNAs were differentially expressed in MB CSF compared with normal, representing TGF-β signaling, TNF-α signaling via NF-kB, and adipogenesis pathways. Tricarboxylic acid cycle and other metabolites (malate, fumarate, succinate, α-ketoglutarate, hydroxypyruvate, N-acetyl-aspartate) and total triacylglycerols were significantly upregulated in MB CSF compared with normal CSF. Although separating MBs into subgroups using transcriptomic, metabolomic, and lipid signatures in CSF was challenging, we were able to identify a group of omics signatures that could separate cancer from normal CSF. Metabolic and lipidomic profiles both contained indicators of tumor hypoxia. Our approach provides several candidate signatures that deserve further validation, including the novel circular RNA circ_463, and insights into the impact of MB on the CSF microenvironment. [ABSTRACT FROM AUTHOR]

Objectives: Ocular amyloidoma is a rare disorder characterized by deposition of insoluble proteinaceous fibrils in the extracellular space of the ocular adnexa. This study details the clinicopathologic features and proteomic characteristics of periocular amyloid deposition.Methods: Specimens (1991-2020) were retrieved and reviewed. All available H&E slides and special stains were reviewed. Proteomic analysis was performed using immunohistochemistry (IHC) for IgG, IgG4, IgA, IgD, IgM, CD20, CD3, CD138, and κ/λ, as well as chromatography-electrospray tandem mass spectrometry on formalin-fixed, paraffin-embedded tissue.Results: There were 14 patients (7 men, 7 women). The depositions involved eyelid (n = 3), conjunctiva (n = 8), and orbit (n = 3). All patients were adults with a median age at diagnosis of 56 (range, 39-88) years. The deposits were predominantly λ light chain restricted (n = 6) and mixed light chains (n = 2), and one case was κ predominant. Two of the cases with a mixture of κ and λ light chains had an excess of transthyretin by mass spectrometry. Four of the cases did not have adequate material for proteomic subtyping.Conclusions: Amyloidomas involving ocular adnexa contain a variety of amyloid-related and immunoglobulin-associated peptides. The λ light chain predominates as in other body sites, but mixed patterns and rarely κ light chain restriction may be encountered. [ABSTRACT FROM AUTHOR]

Medulloblastoma (MB) is the most common malignant brain tumor in children. There remains an unmet need for diagnostics to sensitively detect the disease, particularly recurrences. Cerebrospinal fluid (CSF) provides a window into the central nervous system, and liquid biopsy of CSF could provide a relatively non-invasive means for disease diagnosis. There has yet to be an integrated analysis of the transcriptomic, metabolomic, and lipidomic changes occurring in the CSF of children with MB. CSF samples from patients with (n = 40) or without (n = 11; no cancer) MB were subjected to RNA-sequencing and high-resolution mass spectrometry to identify RNA, metabolite, and lipid profiles. Differentially expressed transcripts, metabolites, and lipids were identified and their biological significance assessed by pathway analysis. The DIABLO multivariate analysis package (R package mixOmics) was used to integrate the molecular changes characterizing the CSF of MB patients. Differentially expressed transcripts, metabolites, and lipids in CSF were discriminatory for the presence of MB but not the exact molecular subtype. One hundred and ten genes and ten circular RNAs were differentially expressed in MB CSF compared with normal, representing TGF-β signaling, TNF-α signaling via NF-kB, and adipogenesis pathways. Tricarboxylic acid cycle and other metabolites (malate, fumarate, succinate, α-ketoglutarate, hydroxypyruvate, N-acetyl-aspartate) and total triacylglycerols were significantly upregulated in MB CSF compared with normal CSF. Although separating MBs into subgroups using transcriptomic, metabolomic, and lipid signatures in CSF was challenging, we were able to identify a group of omics signatures that could separate cancer from normal CSF. Metabolic and lipidomic profiles both contained indicators of tumor hypoxia. Our approach provides several candidate signatures that deserve further validation, including the novel circular RNA circ_463, and insights into the impact of MB on the CSF microenvironment. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) characterized by varying degrees of secondary neurodegeneration. Retinal ganglion cells (RGC) are lost in MS in association with optic neuritis but the mechanisms of neuronal injury remain unclear. Complement component C3 has been implicated in retinal and cerebral synaptic pathology that may precede neurodegeneration. Herein, we examined post-mortem MS retinas, and then used a mouse model, experimental autoimmune encephalomyelitis (EAE), to examine the role of C3 in the pathogenesis of RGC loss associated with optic neuritis. First, we show extensive C3 expression in astrocytes (C3+/GFAP+ cells) and significant RGC loss (RBPMS+ cells) in post-mortem retinas from people with MS compared to retinas from non-MS individuals. A patient with progressive MS with a remote history of optic neuritis showed marked reactive astrogliosis with C3 expression in the inner retina extending into deeper layers in the affected eye more than the unaffected eye. To study whether C3 mediates retinal degeneration, we utilized global C3–/– EAE mice and found that they had less RGC loss and partially preserved neurites in the retina compared with C3+/+ EAE mice. C3–/– EAE mice had fewer axonal swellings in the optic nerve, reflecting reduced axonal injury, but had no changes in demyelination or T cell infiltration into the CNS. Using a C3-tdTomato reporter mouse line, we show definitive evidence of C3 expression in astrocytes in the retina and optic nerves of EAE mice. Conditional deletion of C3 in astrocytes showed RGC protection replicating the effects seen in the global knockouts. These data implicate astrocyte C3 expression as a critical mediator of retinal neuronal pathology in EAE and MS, and are consistent with recent studies showing C3 gene variants are associated with faster rates of retinal neurodegeneration in human disease. [ABSTRACT FROM AUTHOR]

Medulloblastoma, a common pediatric malignant central nervous system tumour, represent a small proportion of brain tumours in adults. Previously it has been shown that in adults, Sonic Hedgehog (SHH)-activated tumours predominate, with Wingless-type (WNT) and Group 4 being less common, but molecular risk stratification remains a challenge. We performed an integrated analysis consisting of genome-wide methylation profiling, copy number profiling, somatic nucleotide variants and correlation of clinical variables across a cohort of 191 adult medulloblastoma cases identified through the Medulloblastoma Advanced Genomics International Consortium. We identified 30 WNT, 112 SHH, 6 Group 3, and 41 Group 4 tumours. Patients with SHH tumours were significantly older at diagnosis compared to other subgroups (p < 0.0001). Five-year progression-free survival (PFS) for WNT, SHH, Group 3, and Group 4 tumours was 64.4 (48.0–86.5), 61.9% (51.6–74.2), 80.0% (95% CI 51.6–100.0), and 44.9% (95% CI 28.6–70.7), respectively (p = 0.06). None of the clinical variables (age, sex, metastatic status, extent of resection, chemotherapy, radiotherapy) were associated with subgroup-specific PFS. Survival among patients with SHH tumours was significantly worse for cases with chromosome 3p loss (HR 2.9, 95% CI 1.1–7.6; p = 0.02), chromosome 10q loss (HR 4.6, 95% CI 2.3–9.4; p < 0.0001), chromosome 17p loss (HR 2.3, 95% CI 1.1–4.8; p = 0.02), and PTCH1 mutations (HR 2.6, 95% CI 1.1–6.2; p = 0.04). The prognostic significance of 3p loss and 10q loss persisted in multivariable regression models. For Group 4 tumours, chromosome 8 loss was strongly associated with improved survival, which was validated in a non-overlapping cohort (combined cohort HR 0.2, 95% CI 0.1–0.7; p = 0.007). Unlike in pediatric medulloblastoma, whole chromosome 11 loss in Group 4 and chromosome 14q loss in SHH was not associated with improved survival, where MYCN, GLI2 and MYC amplification were rare. In sum, we report unique subgroup-specific cytogenetic features of adult medulloblastoma, which are distinct from those in younger patients, and correlate with survival disparities. Our findings suggest that clinical trials that incorporate new strategies tailored to high-risk adult medulloblastoma patients are urgently needed. [ABSTRACT FROM AUTHOR]

Background: Ocular adnexal (OA) sebaceous carcinoma is an aggressive malignancy. Oncologic drivers of ocular sebaceous carcinoma are incompletely understood. Methods: A retrospective search of our pathology archives for OA sebaceous carcinoma identified 18 primary resection specimens. Immunohistochemistry for p16 and ZEB1 and RNA in situ hybridization for high‐risk human papillomavirus (HPV) subtypes were performed. Results: High‐risk HPV was demonstrated in 2/11 (18%) cases. p16 overexpression was observed in 10/11 (91%). No association between gender, age at presentation, tumor location, intraepithelial spread, tumor size, and T stage was observed between HPV‐driven and nonviral cases. High expression of ZEB1 was observed in the intraepithelial component of 4/14 (28%) cases and in the subepithelial component of 1/13 (7%) cases. ZEB1 overexpression was not associated with HPV status, T stage, or tumor size. Conclusion: As previously described by others, our findings suggest that a subset of OA sebaceous carcinomas may arise via an HPV‐dependent pathway. However, unlike high‐risk HPV‐driven carcinomas of the oropharynx, we did not identify an association between HPV‐status and prognostic features. Furthermore, p16 expression was not a useful surrogate marker for HPV‐driven disease. ZEB1 overexpression is not associated with HPV in our cohort of ocular sebaceous carcinoma. [ABSTRACT FROM AUTHOR]

Outcome analysis showed overall survival in patients with infratentorial IDH-mutant astrocytomas to be longer than those with diffuse midline gliomas, but shorter than patients with supratentorial IDH-mutant astrocytomas, specifically those classified as "low grade" by methylation subclass. Keywords: brain biopsy; brainstem glioma; IDH; isocitrate dehydrogenase; low grade glioma; young adult EN brain biopsy brainstem glioma IDH isocitrate dehydrogenase low grade glioma young adult 1 5 5 07/05/21 20210701 NES 210701 Isocitrate dehydrogenase (IDH) mutations are rare in pediatric and adolescent gliomas. Brainstem gliomas are very rare in adults, but approximately 10% of pediatric CNS tumors occur in this location, with diffuse midline glioma, K27M-mutant representing most cases. Brain biopsy, brainstem glioma, IDH, isocitrate dehydrogenase, low grade glioma, young adult. [Extracted from the article]

B Principal component analysis of CSF samples using the 48 most differentially expressed genes showing clear separation of normal CSF samples from MB CSF samples. C Unsupervised clustering of samples using the 48 most differentially expressed genes showing clear separation of normal CSF samples from MB CSF samples. [Extracted from the article]

Retrobulbar fat deposits surround the posterior retina and optic nerve head, but their function and origin are obscure. We report that mouse retrobulbar fat is a neural crest-derived tissue histologically and transcriptionally resembles interscapular brown fat. In contrast, human retrobulbar fat closely resembles white adipose tissue. Retrobulbar fat is also brown in other rodents, which are typically housed at temperatures below thermoneutrality, but is white in larger animals. We show that retrobulbar fat in mice housed at thermoneutral temperature show reduced expression of the brown fat marker Ucp1, and histological properties intermediate between white and brown fat. We conclude that retrobulbar fat can potentially serve as a site of active thermogenesis, that this capability is both temperature and species-dependent, and that this may facilitate regulation of intraocular temperature. [ABSTRACT FROM AUTHOR]

While drug-loaded microparticles (MPs) can serve as drug reservoirs for sustained drug release and therapeutic effects, needle clogging by MPs poses a challenge for ocular drug delivery via injection. Two polymers commonly used in ophthalmic procedures—hyaluronic acid (HA) and methylcellulose (MC)—have been tested for their applicability for ocular injections. HA and MC were physically blended with sunitinib malate (SUN)–loaded PLGA MPs for subconjunctival (SCT) injection into rat eyes. The HA and MC viscous solutions facilitated injection through fine-gauged needles due to their shear-thinning properties as shown by rheological characterizations. The diffusion barrier presented by HA and MC reduced burst drug release and extended overall release from MPs. The significant level of MP retention in the conjunctiva tissue post-operation confirmed the minimal leakage of MPs following injection. The safety of HA and MC for ocular applications was demonstrated histologically. [ABSTRACT FROM AUTHOR]

Keratoconus is a highly prevalent (1 in 2000), genetically complex and multifactorial, degenerative disease of the cornea whose pathogenesis and underlying transcriptomic changes are poorly understood. To identify disease-specific changes and gene expression networks, we performed next generation RNA sequencing from individual corneas of two distinct patient populations - one from the Middle East, as keratoconus is particularly severe in this group, and the second from an African American population in the United States. We conducted a case: control RNA sequencing study of 7 African American, 12 Middle Eastern subjects, and 7 controls. A Principal Component Analysis of all expressed genes was used to ascertain differences between samples. Differentially expressed genes were identified using Cuffdiff and DESeq2 analyses, and identification of over-represented signaling pathways by Ingenuity Pathway Analysis. Although separated by geography and ancestry, key commonalities in the two patient transcriptomes speak of disease - intrinsic gene expression networks. We identified an overwhelming decrease in the expression of anti-oxidant genes regulated by NRF2 and those of the acute phase and tissue injury response pathways, in both patient groups. Concordantly, NRF2 immunofluorescence staining was decreased in patient corneas, while KEAP1, which helps to degrade NRF2, was increased. Diminished NRF2 signaling raises the possibility of NRF2 activators as future treatment strategies in keratoconus. The African American patient group showed increases in extracellular matrix transcripts that may be due to underlying profibrogenic changes in this group. Transcripts increased across all patient samples include Thrombospondin 2 (THBS2), encoding a matricellular protein, and cellular proteins, GAS1, CASR and OTOP2, and are promising biomarker candidates. Our approach of analyzing transcriptomic data from different populations and patient groups will help to develop signatures and biomarkers for keratoconus subtypes. Further, RNA sequence data on individual patients obtained from multiple studies may lead to a core keratoconus signature of deregulated genes and a better understanding of its pathogenesis. [ABSTRACT FROM AUTHOR]

Several generations of poly(β-amino ester) (PBAE) polymers have been developed for efficient cellular transfection. However, PBAE-based gene vectors, similar to other cationic materials, cannot readily provide widespread gene transfer in the brain due to adhesive interactions with the extracellular matrix (ECM). We thus engineered eight vector candidates using previously identified lead PBAE polymer variants but endowed them with non-adhesive surface coatings to facilitate their spread through brain ECM. Specifically, we screened for the ability to provide widespread gene transfer in tumor spheroids and healthy mouse brains. We then confirmed that a lead formulation provided widespread transgene expression in orthotopically established brain tumor models with an excellent in vivo safety profile. Lastly, we developed a method to store it long-term while fully retaining its brain-penetrating property. This new platform provides a broad utility in evaluating novel genetic targets for gene therapy of brain tumors and neurological disorders in preclinical and clinical settings. [ABSTRACT FROM AUTHOR]