The Impact of Spliceosome Inhibition in SF3B1-Mutated Uveal Melanoma.

Purpose: Unfortunately, treatment of patients with uveal melanoma (UM) with metastatic disease is limited. Twenty percent of patients with UM harbor a mutation in the splicing factor gene SF3B1, suggesting that aberrant spliceosome function plays a vital role in tumorigenesis. Splicing inhibitors exploit the preferential sensitivity of spliceosome-compromised leukemic cells to these compounds. Methods: We studied the effect of the splicing inhibitor E7107 using two UM cell lines and ex vivo cultured SF3B1- and BAP1-mutated primary UM tumor slices. These UM cell lines and ex vivo tumor slices were exposed for 24 hours to different concentrations of E7107. Tumor slices were stained with hematoxylin and eosin (H&E) and incubated with BAP1, MelanA, MIB-1, and caspase-3 antisera. Results: The E7107-exposed UM cell lines exhibited decreased cell viability and increased apoptosis, with the greatest effect on SF3B1-mutated UM cells. A similar effect on UM tumor slices was observed upon exposure to E7107. Additionally, RNA was isolated for differential isoform expression analysis. No significant difference in isoform usage was found genome-wide. However, specific genes were differentially expressed after E7107 treatment in the SF3B1-mutated samples. Moreover, E7107 had the greatest effect on intron retention. Conclusions: This study indicates/suggests that mutated SF3B1 UM cells are more sensitive to the splicing inhibitor E7107 than wild-type SF3B1 UM cells.

Vitreoschisis-induced vitreous cortex remnants in proliferative vitreoretinopathy: A comprehensive review from basic research to clinical practice.

Proliferative vitreoretinopathy (PVR) significantly impacts the prognosis of rhegmatogenous retinal detachment (RRD), one of the most critical and increasing causes of vision loss in the Western world. Despite advancements in surgical instruments and techniques, the failure rate due to PVR remains substantial, necessitating additional surgeries and often leading to unsatisfactory visual outcomes. This comprehensive review explores the role of vitreoschisis-induced vitreous cortex remnants (VCR) as a critical, previously under-recognised factor contributing to PVR. Vitreoschisis, a phenomenon where the inner lamellae of the posterior vitreous cortex detach while the outermost layers remain attached to the retina, creates VCR that may contain hyalocytes and serve as scaffolds for fibrocellular proliferation. These remnants are difficult to visualise without triamcinolone acetonide (TA) staining, leading to their frequent lack of recognition in clinical practice. Moreover, removing VCR can be challenging and time-consuming, often requiring meticulous surgical techniques to avoid retinal damage and ensure complete elimination. This review consolidates insights from basic research and clinical practice, emphasising the importance of complete vitreous removal and effective VCR detection and removal to mitigate PVR risks. It highlights the histopathological and clinical evidence supporting the hypothesis that VCR, containing hyalocytes, play a pivotal role in preretinal membrane formation. The review also discusses epidemiological data, surgical management strategies and potential future directions, including improved visualisation techniques and the development of new surgical tools and methods. This review aims to improve surgical outcomes and reduce the frequency and burden of RRD-related complications by addressing VCR as a critical factor in PVR.

Uveal Melanoma Zebrafish Xenograft Models Illustrate the Mutation Status-Dependent Effect of Compound Synergism or Antagonism.

Purpose: Uveal melanoma (UM) is the most common primary intraocular malignancy with a high probability of metastatic disease. Although excellent treatment options for primary UM are available, therapy for metastatic disease remain limited. Drug discovery studies using mouse models have thus far failed to provide therapeutic solutions, highlighting the need for novel models. Here, we optimize zebrafish xenografts as a potential model for drug discovery by showcasing the behavior of multiple cell lines and novel findings on mutation-dependent compound synergism/antagonism using Z-Tada; an algorithm to objectively characterize output measurements. Methods: Prognostic relevant primary (N = 4) and metastatic UM (N = 1) cell lines or healthy melanocytes (N = 2) were inoculated at three distinct inoculation sites. Standardized quantifications independent of inoculation site were obtained using Z-Tada; an algorithm to measure tumor burden and the number, size, and distance of disseminated tumor cells. Sequentially, we utilized this model to validate combinatorial synergism or antagonism seen in vitro. Results: Detailed analysis of 691 zebrafish xenografts demonstrated perivitelline space inoculation provided robust data with high probability of cell dissemination. Cell lines with more invasive behavior (SF3B1mut and BAP1mut) behaved most aggressive in this model. Combinatorial drug treatment illustrated synergism or antagonism is mutation-dependent, which were confirmed in vivo. Combinatorial treatment differed per xenograft-model, as it either inhibited overall tumor burden or cell dissemination. Conclusions: Perivitelline space inoculation provides robust zebrafish xenografts with the ability for high-throughput drug screening and robust data acquisition using Z-Tada. This model demonstrates that drug discovery for uveal melanoma must take mutational subclasses into account, especially in combinatorial treatment discoveries.

Prediction of molecular subclasses of uveal melanoma by deep learning using routine haematoxylin-eosin-stained tissue slides.

AIMS: Uveal melanoma has a high propensity to metastasize. Prognosis is associated with specific driver mutations and copy number variations, and these can only be obtained after genetic testing. In this study we evaluated the efficacy of patient outcome prediction using deep learning on haematoxylin and eosin (HE)-stained primary uveal melanoma slides in comparison to molecular testing. METHODS: In this retrospective study of patients with uveal melanoma, 113 patients from the Erasmus Medical Centre who underwent enucleation had tumour tissue analysed for molecular classification between 1993 and 2020. Routine HE-stained slides were scanned to obtain whole-slide images (WSI). After annotation of regions of interest, tiles of 1024 × 1024 pixels were extracted at a magnification of 40×. An ablation study to select the best-performing deep-learning model was carried out using three state-of-the-art deep-learning models (EfficientNet, Vision Transformer, and Swin Transformer). RESULTS: Deep-learning models were subjected to a training cohort (n = 40), followed by a validation cohort (n = 20), and finally underwent a test cohort (n = 48). A k-fold cross-validation (k = 3) of validation and test cohorts (n = 113 of three classes: BAP1, SF3B1, EIF1AX) demonstrated Swin Transformer as the best-performing deep-learning model to predict molecular subclasses based on HE stains. The model achieved an accuracy of 0.83 ± 0.09 on the validation cohort and 0.75 ± 0.04 on the test cohort. Within the subclasses, this model correctly predicted 70% BAP1-mutated, 61% SF3B1-mutated and 80% EIF1AX-mutated UM in the test set. CONCLUSIONS: This study showcases the potential of the deep-learning methodology for predicting molecular subclasses in a multiclass manner using HE-stained WSI. This development holds promise for advanced prognostication of UM patients without the need of molecular or immunohistochemical testing. Additionally, this study suggests there are distinct histopathological features per subclass; mainly utilizing epithelioid cellular morphology for BAP1-classification, but an unknown feature distinguishes EIF1AX and SF3B1.

Comparison of stereotactic radiotherapy and protons for uveal melanoma patients.

Background and purpose: Uveal melanoma (UM) is the most common primary ocular malignancy. We compared fractionated stereotactic radiotherapy (SRT) with proton therapy, including toxicity risks for UM patients. Materials and methods: For a total of 66 UM patients from a single center, SRT dose distributions were compared to protons using the same planning CT. Fourteen dose-volume parameters were compared in 2-Gy equivalent dose per fraction (EQD2). Four toxicity profiles were evaluated: maculopathy, optic-neuropathy, visual acuity impairment (Profile I); neovascular glaucoma (Profile II); radiation-induced retinopathy (Profile III); and dry-eye syndrome (Profile IV). For Profile III, retina Mercator maps were generated to visualize the geographical location of dose differences. Results: In 9/66 cases, (14 %) proton plans were superior for all dose-volume parameters. Higher T stages benefited more from protons in Profile I, especially tumors located within 3 mm or less from the optic nerve. In Profile II, only 9/66 cases resulted in a better proton plan. In Profile III, better retina volume sparing was always achievable with protons, with a larger gain for T3 tumors. In Profile IV, protons always reduced the risk of toxicity with a median RBE-weighted EQD2 reduction of 15.3 Gy. Conclusions: This study reports the first side-by-side imaging-based planning comparison between protons and SRT for UM patients. Globally, while protons appear almost always better regarding the risk of optic-neuropathy, retinopathy and dry-eye syndrome, for other toxicity like neovascular glaucoma, a plan comparison is warranted. Choice would depend on the prioritization of risks.

Protein and mRNA Expression in Uveal Melanoma Cell Lines Are Related to GNA and BAP1 Mutation Status.

Purpose: Cell lines are being used in preclinical uveal melanoma (UM) research. Because not all cell lines harbor typical GNAQ or GNA11 hotspot mutations, we aimed at better classifying them and determining whether we could find genetic causes to explain the protein and mRNA expression profiles of the cell lines. Methods: We studied protein and mRNA expression of 14 UM cell lines and determined the presence of single nucleotide variants and small insertions and deletions with next-generation sequencing and copy number alterations with a single nucleotide polymorphism array. The lists of differentially expressed proteins and genes were merged, and shared lists were created, keeping only terms with concordant mRNA and protein expression. Enrichment analyses were performed on the shared lists. Results: Cell lines Mel285 and Mel290 are separate from GNA-mutated cell lines and show downregulation of melanosome-related markers. Both lack typical UM mutations but each harbors four putatively deleterious variants in CTNNB1, PPP1R10, LIMCH1, and APC in Mel285 and ARID1A, PPP1R10, SPG11, and RNF43 in Mel290. The upregulated terms in Mel285 and Mel290 did not point to a convincing alternative origin. Mel285 shows loss of chromosomes 1p, 3p, partial 3q, 6, and partial 8p, whereas Mel290 shows loss of 1p and 6. Expression in the other 12 cell lines was related to BAP1 expression. Conclusions: Although Mel285 and Mel290 have copy number alterations that fit UM, multi-omics analyses show that they belong to a separate group compared to the other analyzed UM cell lines. Therefore, they may not be representative models to test potential therapeutic targets for UM.

Carbenoxolone mitigates extensive fibrosis formation in PLP-induced EAE model and multiple sclerosis serum-exposed pericyte culture.

Introduction: Multiple sclerosis (MS) is one of the most common causes of disability in young adults. Nearly, 85% of MS cases start with attacks and remissions, classified as relapsing-remitting multiple sclerosis (RRMS). With repeating attacks, MS causes brain-spinal cord atrophy and enhanced disability as disease progresses. PLP-induced EAE is one of the most established models for pathophysiology and treatment of RRMS. Recent studies demonstrated the possible role of pericytes in perivascular and intra-lesional fibrosis in PLP-induced EAE, whose importance remains elusive. Hence, we have investigated the possible role of pericytes in fibrosis formation and amelioration with a hemichannel blocker, Carbenoxolone (CBX). Methods: PLP-induced experimental autoimmune encephalitis (EAE) model is used and the effect of CBX is investigated. Clinical scores were recorded and followed. Perivascular Collagen 1 and 3 accumulations were demonstrated as markers of fibrosis in the spinal cord. To delineate the role of pericytes, human brain vascular pericytes (HBVP) were incubated with the sera of MS patients to induce in-vitro MS model and the fibrosis formation was investigated. Results: In the PLP induced in-vivo model, both intracerebroventricular and intraperitoneal CBX have significantly mitigated the disease progression followed by clinical scores, demyelination, and fibrosis. Moreover, CBX significantly mitigated MS-serum-induced fibrosis in the HBVP cell culture. Discussion: The study demonstrated two important findings. First, CBX decreases fibrosis formation in both in-vivo and in-vitro MS models. Secondly, it improves neurological scores and decreases demyelination in the EAE model. Therefore, CBX can be potential novel therapeutic option in treating Multiple Sclerosis.

The Pediatric and Young Adult Choroidal and Ciliary Body Melanoma Genetic Study, A Survey by the European Ophthalmic Oncology Group.

Purpose: To explore the genetic background of choroidal and ciliary body melanoma among children and young adults, with special focus on BAP1 germline variants in this age group. Methods: Patients under the age of 25 and with confirmed choroidal or ciliary body melanoma were included in this retrospective, multicenter observational study. Nuclear BAP1 immunopositivity was used to evaluate the presence of functional BAP1 in the tumor. Next-generation sequencing using Ion Torrent platform was used to determine pathogenic variants of BAP1, EIF1AX, SF3B1, GNAQ and GNA11 and chromosome 3 status in the tumor or in DNA extracted from blood or saliva. Survival was analyzed using Kaplan-Meier estimates. Results: The mean age at diagnosis was 17 years (range 5.0-24.8). A germline BAP1 pathogenic variant was identified in an 18-year-old patient, and a somatic variant, based mainly on immunohistochemistry, in 13 (42%) of 31 available specimens. One tumor had a somatic SF3B1 pathogenic variant. Disomy 3 and the absence of a BAP1 pathogenic variant in the tumor predicted the longest metastasis-free survival. Males showed longer metastasis-free survival than females (P = 0.018). Conclusions: We did not find a stronger-than-average BAP1 germline predisposition for choroidal and ciliary body melanoma among children and young adults compared to adults. Males had a more favorable survival and disomy 3, and the absence of a BAP1 mutation in the tumor tissue predicted the most favorable metastasis-free survival. A BAP1 germline pathogenic variant was identified in one patient (1%), and a somatic variant based mainly on immunohistochemistry in 13 (42%).

Evaluation of Circulating Tumor DNA as a Liquid Biomarker in Uveal Melanoma.

Purpose: Uveal melanoma (UM) has a high propensity to metastasize. Prognosis is associated with specific driver mutations and copy number variations (CNVs), but limited primary tumor tissue is available for molecular characterization due to eye-sparing irradiation treatment. This study aimed to assess the rise in circulating tumor DNA (ctDNA) levels in UM and evaluate its efficacy for CNV-profiling of patients with UM. Methods: In a pilot study, we assessed ctDNA levels in the blood of patients with UM (n = 18) at various time points, including the time of diagnosis (n = 13), during fractionated stereotactic radiotherapy (fSRT) treatment (n = 6), and upon detection of metastatic disease (n = 13). Shallow whole-genome sequencing (sWGS) combined with in silico size-selection was used to identify prognostically relevant CNVs in patients with UM (n = 26) from peripheral blood retrieved at the time of diagnosis (n = 9), during fSRT (n = 5), during post-treatment follow-up (n = 4), metastasis detection (n = 6), and metastasis follow-up (n = 4). Results: A total of 34 patients had blood analyzed for ctDNA detection (n = 18) and/or CNV analysis (n = 26) at various time points. At the time of diagnosis, 5 of 13 patients (38%) had detectable ctDNA (median = 0 copies/mL). Upon detection of metastatic disease, ctDNA was detected in 10 of 13 patients (77%) and showed increased ctDNA levels (median = 24 copies/mL, P < 0.01). Among the six patients analyzed during fSRT, three (50%) patients had detectable ctDNA at baseline and three of six (50%) patients had undetectable levels of ctDNA. During the fSRT regimen, ctDNA levels remained unchanged (P > 0.05). The ctDNA fractions were undetectable to low in localized disease, and sWGS did not elucidate chromosome 3 status from blood samples. However, in 7 of 10 (70%) patients with metastases, the detection of chromosome 3 loss corresponded to the high metastatic-risk class. Conclusions: The rise in ctDNA levels observed in patients with UM harboring metastases suggests its potential utility for CNV profiling. These findings highlight the potential of using ctDNA for metastasis detection and patient inclusion in therapeutic studies targeting metastatic UM.

8q Gain Has No Additional Predictive Value in SF3B1MUT Uveal Melanoma but Is Predictive for a Worse Prognosis in Patients with BAP1MUT Uveal Melanoma.

Purpose: Gain of chromosome 8q has been associated with poor prognosis in uveal melanoma (UM), and an increase in the absolute number of 8q-copies correlated with an even shorter survival. Splicing factor 3b subunit 1 (SF3B1)-mutated (SF3B1MUT) tumors display structural chromosomal anomalies and frequently show a partial gain of chromosome 8qter. A recent subset of SF3B1MUT UM with early-onset metastases has been identified, prompting the investigation of the relationship between survival, 8q gain, and SF3B1MUT UM. Design: Retrospective cohort study. Subjects: Patients diagnosed with UM who underwent enucleation or received a biopsy at the Erasmus MC Cancer Institute or the Rotterdam Eye Hospital, The Netherlands were included. Methods: Fifty-nine patients with SF3B1MUT tumors and 211 patients with BRCA1 associated protein 1 (BAP1)-mutated (BAP1MUT) tumors were included in this study. Copy number status and gene expression were assessed using either a single nucleotide polymorphism array, fluorescence in situ hybridization, and karyotyping, or a combination of these techniques. Disease-free survival was determined and a cut-off of 60 months was used to define early-onset metastatic disease. Main Outcome Measures: Disease-free survival. Results: Forty-eight patients with SF3B1MUT UM (81%) had chromosome 8q gain (3 copies, 78%; 4 copies, 22%). Kaplan-Meier analysis of SF3B1MUT UM did not indicate a difference in survival in patients with or without gain of 8q (P = 0.99). Furthermore, the number of 8q copies was not associated with survival when comparing early (P = 0.97) versus late (P = 0.23) metastases group. In contrast, the presence of 8q gain (86%) was correlated with a decreased survival in BAP1MUT UM (P = 0.013). Conclusions: We did not find a correlation between 8q gain and early-onset metastasis in SF3B1MUT tumors. Gain of 8q has no additional predictive value in SF3B1MUT tumors. In contrast, 8q gain is predictive of a worse prognosis in patients with BAP1MUT tumors. Thus, gain of chromosome 8q has additional predictive value for BAP1MUT tumors, but not for SF3B1MUT tumors. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Uveal melanoma modeling in mice and zebrafish.

Despite extensive research and refined therapeutic options, the survival for metastasized uveal melanoma (UM) patients has not improved significantly. UM, a malignant tumor originating from melanocytes in the uveal tract, can be asymptomatic and small tumors may be detected only during routine ophthalmic exams; making early detection and treatment difficult. UM is the result of a number of characteristic somatic alterations which are associated with prognosis. Although UM morphology and biology have been extensively studied, there are significant gaps in our understanding of the early stages of UM tumor evolution and effective treatment to prevent metastatic disease remain elusive. A better understanding of the mechanisms that enable UM cells to thrive and successfully metastasize is crucial to improve treatment efficacy and survival rates. For more than forty years, animal models have been used to investigate the biology of UM. This has led to a number of essential mechanisms and pathways involved in UM aetiology. These models have also been used to evaluate the effectiveness of various drugs and treatment protocols. Here, we provide an overview of the molecular mechanisms and pharmacological studies using mouse and zebrafish UM models. Finally, we highlight promising therapeutics and discuss future considerations using UM models such as optimal inoculation sites, use of BAP1mut-cell lines and the rise of zebrafish models.

Time Trends in the Treatment and Survival of 5036 Uveal Melanoma Patients in The Netherlands over a 30-Year Period.

BACKGROUND: Uveal melanoma (UM) is a rare intraocular tumor with a dismal prognosis once metastasized. This study provides a nationwide overview and time trends of patients diagnosed with primary UM in the Netherlands between 1989 and 2019. METHODS: A retrospective population-based cohort study based on patients with primary UM from the database of the Netherlands Cancer Registry (NCR), linked with the national population registry Statistics Netherlands on inhabitants' cause of death. Two time periods (1989-2004, 2005-2019) were compared with descriptive statistics. Kaplan-Meier and (multivariate) Cox proportional hazard models were used to assess changes over time for overall survival (OS) and cancer-specific survival (CSS). RESULTS: In total, 5036 patients were analyzed with a median age of 64.0 years at the time of diagnosis. The number of patients increased over time. In the first (1989-2004) and second (2005-2019) period, 32% versus 54% of the patients received radiotherapy (p < 0.001). The median FU time was 13.4 years. The median OS of the first and second periods was 9.5 (95% CI 8.7-10.3) versus 11.3 years (95% CI 10.3-12.3; p < 0.001). The median CSS was 30.0 years (95% CI NA) in the first period and not reached in the second period (p = 0.008). In multivariate analysis (MVA), female gender (HR 0.85; 95% CI 0.79-0.92, p < 0.001) and radiotherapy treatment (HR 0.73; 95% CI 0.64-0.83, p < 0.001) were associated with better OS. Radiotherapy treatment (HR 0.74; 95% CI 0.61-0.90, p = 0.002) was also associated with better CSS. The period of diagnosis was not associated with OS or CSS. CONCLUSIONS: In this study of patients with primary UM, there was a shift to the diagnosis of smaller tumors, possibly due to stage migration. There was also an increase in eye-preserving treatments over time. OS and CSS were modestly improved in the second time period; however, the time period was not associated with OS or CSS in multivariate analyses.

Worldwide Incidence of Ocular Melanoma and Correlation With Pigmentation-Related Risk Factors.

Purpose: The worldwide incidence of ocular melanoma (OM), uveal melanoma (UM), and conjunctival melanoma has last been reported on 15 years ago. Recently, light iris color and four specific single-nucleotide-polymorphisms (SNPs) have been identified as a UM-risk factor. Furthermore, six iris color predicting SNPs have been discovered (IrisPlex). Interestingly, two of these (rs129138329 and rs12203592) are also UM-risk factors. We collected worldwide incidence data of OM and investigated its correlations with iris color, IrisPlex SNPs, and UM-risk SNPs. Methods: Cases of OM, as defined by the International Classification of Diseases Oncology C69 (eye), 8720/3 to 8790/3 (malignant melanoma), and 8000 to 8005 (malignant neoplasm), between 1988 and 2012, were extracted from the Cancer Incidence in Five Continents. Incidence rates were age-standardized and their trends were analyzed with joinpoint regression and age period cohort modeling. Frequencies for each country of iris color, IrisPlex SNPs, and UM-risk SNPs were collected from the literature. Results: Incidence rates were generally ≥8.0 cases per million person-years in Northern Europe, Western Europe, and Oceania; 2.0 to 7.9 in North America, Eastern Europe, and Southern Europe; and <2.0 in South America, Asia, and Africa. OM incidence correlated with latitude (r = 0.77, P ≤ 0.001) and is expressed as a north-to-south decreasing gradient in Europe. SNP rs12913832 correlated with OM incidence (r = 0.83, P ≤ 0.001), blue iris color (r = 0.56, P ≤ 0.05), green iris color (r = 0.51, P ≤ 0.05), and brown iris color (r = -0.64, P ≤ 0.01). Trends were stable for most countries (28/35). Conclusions: OM incidence is highest in populations of European ancestry and lowest in populations of Asian and African ancestry. Overall, trends are stable, and the spatial correlation among OM incidence, iris color, and rs12913832 may support the role of pigmentation-related risk factors in OM development.

Novel Surgical Treatment of an Intraretinal Juxtapapillary Hemangioblastoma Using Intraocular Diathermy Forceps: A Case Report.

The surgical treatment of intraretinal juxtapapillary retinal hemangioblastomas (JRHs) was previously contraindicated because of the significant risk of collateral damage to the macula and optic nerve. This case report discusses the effectiveness and safety of a novel surgical technique using intraocular bipolar diathermy forceps to coagulate feeder and draining blood vessels of an intraretinal JRH. The patient suffered from bilateral retinal hemangioblastomas with loss of visual function in one eye and the development of an intraretinal JRH in the other eye. Despite intensive treatment with intravitreal bevacizumab and subconjunctival triamcinolone acetonide, growth of the intraretinal JRH continued, macular exudation worsened, and visual acuity decreased. Surgical treatment was undertaken in which, first, the feeder and draining vessels of the JRH were identified by comparing the retinal imaging of the JRH with the imaging before the emergence of the JRH 4 years earlier. Then, retinal incisions were made above the blood vessels and parallel to the nerve fibers during a pars plana vitrectomy. Lastly, these vessels were lifted above the retinal surface and coagulated using intraocular diathermy forceps. Postoperatively, macular edema reduced, and visual acuity increased and remained stable for about 6 months. Using intraocular diathermy forceps, this case report demonstrates effective and safe intraretinal JRH blood vessel coagulation above the retinal surface. This novel surgical approach was able to delay the deterioration of visual acuity due to tumor growth and exudation in this patient. This suggests that coagulation with intraocular diathermy forceps can be considered an additional surgical treatment option for JRHs, especially those with an intraretinal growth pattern.

ATRX Loss in the Development and Prognosis of Conjunctival Melanoma.

Metastatic disease is linked to TERT promoter mutations in conjunctival melanomas (CM). Both TERT promoter and ATRX mutations are associated with faulty telomere maintenance. This study aimed to determine the prognostic value of ATRX loss in conjunctival melanocytic lesions. Eighty-six conjunctival melanocytic lesions from the Rotterdam Ocular Melanoma Study group were collected. ATRX status and TERT promoter status were determined using immunohistochemical staining and molecular diagnostics, respectively. None of the nevi (n = 16) and primary acquired melanosis (PAM) without atypia (n = 6) showed ATRX loss. ATRX loss was found in 2/5 PAM with atypia without CM and in 8/59 CM. No cases with a TERT promoter mutation (n = 26) showed ATRX loss. Eight/eleven metastatic CM harbored a TERT promoter mutation, two other metastatic CM showed ATRX loss and one metastatic case showed no TERT promoter/ATRX alterations. In conclusion ATRX loss and TERT promoter mutations are only found in (pre)malignant conjunctival melanocytic lesions, with most metastatic cases harboring one of these alterations, suggesting that both alterations are associated with adverse behavior. Similar to TERT promoter mutations, ATRX loss may be used as a diagnostic tool in determining whether a conjunctival melanocytic lesion is prone to having an adverse course.

Uveal Melanoma Patients Have a Distinct Metabolic Phenotype in Peripheral Blood.

Uveal melanomas (UM) are detected earlier. Consequently, tumors are smaller, allowing for novel eye-preserving treatments. This reduces tumor tissue available for genomic profiling. Additionally, these small tumors can be hard to differentiate from nevi, creating the need for minimally invasive detection and prognostication. Metabolites show promise as minimally invasive detection by resembling the biological phenotype. In this pilot study, we determined metabolite patterns in the peripheral blood of UM patients (n = 113) and controls (n = 46) using untargeted metabolomics. Using a random forest classifier (RFC) and leave-one-out cross-validation, we confirmed discriminatory metabolite patterns in UM patients compared to controls with an area under the curve of the receiver operating characteristic of 0.99 in both positive and negative ion modes. The RFC and leave-one-out cross-validation did not reveal discriminatory metabolite patterns in high-risk versus low-risk of metastasizing in UM patients. Ten-time repeated analyses of the RFC and LOOCV using 50% randomly distributed samples showed similar results for UM patients versus controls and prognostic groups. Pathway analysis using annotated metabolites indicated dysregulation of several processes associated with malignancies. Consequently, minimally invasive metabolomics could potentially allow for screening as it distinguishes metabolite patterns that are putatively associated with oncogenic processes in the peripheral blood plasma of UM patients from controls at the time of diagnosis.

Perivascular PDGFRB+ cells accompany lesion formation and clinical evolution differentially in two different EAE models.

BACKGROUND: Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) that may lead to progressive disability. Here, we explored the behavioral pattern and the role of vasculature especially PDGFRB+ pericytes/ perivascular cells, in MS pathogenesis. METHODS: We have evaluated vascular changes in two different experimental allergic encephalomyelitis (EAE) mice models (MOG and PLP-induced). PDGFRB+ cells demonstrated distinct and different behavioral patterns. In both models, fibrosis formation was detected via collagen, fibronectin, and extracellular matrix accumulation. RESULTS: The PLP-induced animal model revealed that fibrosis predominantly occurs in perivascular locations and that PDGFRB+ cells are accumulated around vessels. Also, the expression of fibrotic genes and genes coding extracellular matrix (ECM) proteins are upregulated. Moreover, the perivascular thick wall structures in affected vessels of this model presented primarily increased PDGFRB+ cells but not NG2+ cells in the transgenic NG2-DsRed transgenic animal model. On the other hand, in MOG induced model, PDGFRB+ perivascular cells were accumulated at the lesion sites. PDGFRB+ cells colocalized with ECM proteins (collagen, fibronectin, and lysyl oxidase L3). Nevertheless, both MOG and PLP-immunized mice showed increasing EAE severity, and disability parallel with enhanced perivascular cell accumulation as the disease progressed from earlier (day 15) to later (day 40). CONCLUSION: As a result, we have concluded that PDGFRB+ perivascular cells may be participating in lesion progression and as well as demonstrating different responses in different EAE models.

Investigation of Factors Affecting the Side of the Disease Onset in Parkinson's Disease.

Introduction: Parkinson's disease (PD) is a progressive neurodegenerative disease that starts unilaterally in almost all cases and tends to emerge on the side of the dominant hand, but what we know about the cause of this lateralization is limited. Frequent use of the extremity and physical activity are argued to be protective from PD in preclinical and clinical studies. This study aimed to evaluate the effect of handedness and working in occupations that require continuous use of upper extremities on the disease onset-side. Methods: We retrospectively collected 84 PD patients who applied to Koç University Neurology outpatient clinic between July 2016-October 2018. We analyzed the parameters of the side and region of disease onset, age of onset, number of drugs used for PD, hand preference, and patients' occupations. Results: The median age of our study group was 61 (53-69). Thirty (36%) of the 84 patients were women. Seventy-nine patients (94%) were right-handed. Eighty-three (99%) had asymmetric onset. The disease started on the dominant hand side in 47 patients (57%) and on the non-dominant hand side in 36 (43%) patients. In our group with a median disease duration of four (2-7) years, the side with more severe complaints measured with the Unified Parkinson's Disease Evaluation Scale was consistent with the onset-side of the disease (p<0.001). In addition, the number of drugs used for PD and the scale score were higher in patients with longer disease duration (p=0.039, p=0.005). The number of drugs used for PD was also higher in patients with lower extremity-onset or both upper and lower extremities affected simultaneously than the upper extremity-onset (p=0.005). While the probability of starting on the dominant side was 43% in patients working in occupations requiring continuous use of upper extremities, it was 65% in others (p=0.027). Conclusion: According to this study, the onset of PD tends to be on the dominant hand side. Continuous upper extremity use may reduce the possibility of starting on the dominant side.

High C-Reactive Protein Levels Are Related to Better Survival in Patients with Uveal Melanoma.

Purpose: To determine whether peripheral blood leukocyte numbers and serum markers of inflammation can be used to predict which patients with primary uveal melanoma will develop metastasis. Design: Retrospective study. Participants: Medical records of patients with uveal melanoma (UM) who received treatment for primary UM between February 1992 and December 2020 at the Erasmus University Medical Center (Rotterdam, The Netherlands) and the Rotterdam Eye Hospital (Rotterdam, The Netherlands) were reviewed. Methods: Inclusion criteria were the presence of a melanoma of the choroid or ciliary body and the availability of data from peripheral blood samples taken before treatment of the melanoma. Data including patient demographics, C-reactive protein (CRP) levels; erythrocyte sedimentation rate (ESR); number of leukocytes, neutrophils, monocytes, and lymphocytes; and histopathologic findings were obtained from medical records. Neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were calculated. Main Outcome Measures: Metastasis-free survival. Results: Of the 807 patients with UM, serum and leukocyte data were available for 183 of them at the time of primary tumor treatment. In the total group, no correlation was found between ESR before treatment; the number of leukocytes; percentages of neutrophils, monocytes, and lymphocytes; or NLR or LMR values and any of the clinical characteristics or metastasis-free survival. Among patients who underwent enucleation, those with negative BAP1 findings showed significantly lower numbers of leukocytes (P < 0.05). In the entire cohort, a significant association was found between high CRP levels and longer metastasis-free survival (MFS; P = 0.049). Conclusions: The total blood leukocyte number was related to loss of BAP1 staining in patients who underwent enucleation, with lower leukocyte counts correlating with absent BAP1 staining. Higher CRP levels were associated with a longer MFS in the entire cohort. Neither the NLR nor the LMR is a good predictor for metastasis developing in patients with UM.