TREM2, a critical activator of pyroptosis, mediates the anti­tumor effects of piceatannol in uveal melanoma cells via caspase 3/GSDME pathway

Uveal melanoma (UM) is the most prevalent type of primary intraocular malignancy and is prone to metastasize, particularly to the liver. However, due to the poor understanding of the pathogenesis of UM, effective therapeutic approaches are lacking. As a phenolic compound extracted from grapes, piceatannol (PIC) exhibits anti­cancer properties. To the best of our knowledge, however, the effects of PIC on UM have not been well investigated. Therefore, in the present study, considering the impact of pyroptosis on modulating cell viability, the mechanism underlying the effects of PIC on UM cell proliferation was explored. The inhibitory effect of PIC on proliferation of UM cells was detected by cell counting kit­8 assay. Wound healing was used to investigate the effects of PIC on the migration of UM cells. Activity detecting assays were performed to test the apoptosis and oxidant level in UM cells. Western blotting and RT­qPCR were used to detect the inflammatory and pyroptotic levels of UM cell after PIC treatment. PIC­treated UM cells were screened by high­throughput sequencing to detect the differential expression of RNA and differential genes. Si­TREM2 transfection was used to verify the important role of TREM2 in the effects of PIC. Immunohistochemical staining was used to observe the expressions of TREM2 and GSDMR of tumor in nude mice after PIC administration. PIC effectively inhibited proliferation ability of C918 and Mum­2b UM cell lines via enhancing apoptosis, as evidenced by enhanced activities of caspase 3 and caspase 9. In addition, treatment of UM cells with PIC attenuated cell migration in a dose­dependent manner. PIC increased reactive oxygen species levels and suppressed the activity of the antioxidant enzymes superoxide dismutase, glutathione­S­transferase, glutathione peroxidase and catalase. PIC inhibited inflammatory responses in C918 cells. PIC treatment upregulated IL­1ß, IL­18 and Nod­like receptor protein 3 and downregulated gasdermin D (GSDMD). RNA sequencing results revealed the activation of an unconventional pyroptosis­associated signaling pathway, namely caspase 3/GSDME signaling, following PIC treatment, which was mediated by triggering receptor expressed on myeloid cells 2 (TREM2) upregulation. As an agonist of TREM2, COG1410­mediated TREM2 upregulation inhibited proliferation of C918 cells, displaying similar effects to PIC. Furthermore, PIC inhibited tumor growth via regulating the TREM2/caspase 3/GSDME pathway in a mouse model. Collectively, the present study revealed a novel mechanism underlying the inhibitory effects of PIC on UM, providing a potential treatment approach for UM in clinic.

The roles of genetic mutation and cytokines/chemokines in immune response and their association with uveal melanoma patient outcome.

The impact of tumor mutations and the interplay of cytokines and chemokines on the immune response and clinical outcomes in uveal melanoma (UM) warrants further exploration. In our study, we delved into the correlation between genetic alterations and survival rates in a cohort of 188 UM patients, utilizing data from cBioPortal. We assessed the composition of immune cell populations within 80 UM tumors by examining RNA sequence-based gene expression data from The Cancer Genome Atlas (TCGA). Furthermore, we scrutinized the relationship between genetic mutations and the expression of cytokines and chemokines, as well as their influence on various immune cell subsets. Our investigation revealed a significant association between the presence of mutated GNAQ or SF3B1 genes and improved progression-free survival (PFS), disease-specific survival (DSS), and overall survival (OS) when compared to patients with non-mutated counterparts. In contrast, the presence of immune response gene mutations was associated with a detrimental effect on PFS, DSS, and OS. We also observed that the expression levels of cytokines and chemokines were positively linked to the infiltration of immune killer cells and inversely related to the populations of B cells and dendritic cells. Elevated expression levels of PDCD1, TNF, IL6, CXCL9, and CXCL10 were found to be correlated with reduced OS. Intriguingly, an increase in CD8+ T cell populations was associated with a poorer OS, a finding that warrants further investigation. These findings underscore the potential utility of cytokines/chemokines expression levels, immune cell subsets, and mutation status as critical biomarkers for the selection of patients who are most likely to benefit from immunotherapeutic interventions. Our research provides valuable insights that could guide the development of more targeted and effective treatment strategies for UM patients.

Germline Variants in Patients Affected by Both Uveal and Cutaneous Melanoma.

Uveal melanoma (UM) and nonacral cutaneous melanoma (CM) are distinct entities with varied genetic landscapes despite both arising from melanocytes. There are, however, similarities in that they most frequently affect people of European ancestry, and high penetrance germline variants in BAP1, POT1 and CDKN2A have been shown to predispose to both UM and CM. This study aims to further explore germline variants in patients affected by both UM and CM, shedding light on the underlying genetic mechanism causing these diseases. Using exome sequencing we analysed germline DNA samples from a cohort of 83 Australian patients diagnosed with both UM and CM. Eight (10%) patients were identified that carried pathogenic mutations in known melanoma predisposition genes POT1, MITF, OCA2, SLC45A2 and TYR. Three (4%) patients carried pathogenic variants in genes previously linked with other cancer syndromes (ATR, BRIP1 and MSH6) and another three cases carried monoallelic pathogenic variants in recessive cancer genes (xeroderma pigmentosum and Fanconi anaemia), indicating that reduced penetrance of phenotype in these individuals may contribute to the development of both UM and CM. These findings highlight the need for further studies characterising the role of these genes in melanoma susceptibility.

Local anesthetic tetracaine hydrochloride induces pyroptosis via caspase-3/gasdermin E in uveal melanoma.

BACKGROUND: Evasion of pyroptosis is an effective survival strategy employed by cancer cells to evade immune cell attacks and drug-induced cytotoxicity. Exploring potent molecules capable of inducing pyroptosis in cancer cells has significant clinical implications for the control of cancer progression. Unexpectedly, we found that the local anesthetic tetracaine hydrochloride (TTC) induced pyroptosis, specifically in uveal melanoma but not in acral or cutaneous melanoma. METHODS: We investigated the effects of TTC on various melanoma cell lines and performed transcriptome sequencing of TTC-treated uveal melanoma cells. The role of gasdermin E (GSDME), an executive protein responsible for pyroptosis, was explored using CRISPR-Cas13d knockdown, caspase-3 inhibitor treatment, and western blot analysis. Differential gene expression and pathway enrichment analyses were performed. Furthermore, we used tissue microarrays to assess GSDME expression levels in melanoma tissues from different anatomical sites. RESULTS: TTC significantly induced pyroptosis specifically in uveal melanoma cells with high GSDME expression levels. TTC treatment could lead to GSDME cleavage by the caspase-3 in uveal melanoma C918 cells. GSDME knockdown or caspase-3 inhibition suppressed TTC-induced pyroptosis. Transcriptome analysis revealed differentially expressed genes enriched in signaling pathways related to pyroptosis, immunity, and cytokines. CONCLUSIONS: This study showed that the local anesthetic TTC effectively induces pyroptosis in uveal melanoma through the caspase-3/GSDME pathway, highlighting its potential application in immunotherapy. Notably, the use of TTC has potential as an agent for inducing pyroptosis and as an adjuvant anticancer therapy in uveal melanoma.

New Insights into the Exosome-Induced Migration of Uveal Melanoma Cells and the Pre-Metastatic Niche Formation in the Liver.

UM is an aggressive intraocular tumor characterized by high plasticity and a propensity to metastasize in the liver. However, the underlying mechanisms governing liver tropism remain poorly understood. Given the emerging significance of exosomes, we sought to investigate the contribution of UM-derived exosomes to specific steps of the metastatic process. Firstly, we isolated exosomes from UM cells sharing a common genetic background and different metastatic properties. A comparison of protein cargo reveals an overrepresentation of proteins related to cytoskeleton remodeling and actin filament-based movement in exosomes derived from the parental cells that may favor the detachment of cells from the primary site. Secondly, we assessed the role of macrophages in reprogramming the HHSCs by exosomes. The activation of HHSCs triggered a pro-inflammatory and pro-fibrotic environment through cytokine production, upregulation of extracellular matrix molecules, and the activation of signaling pathways. Finally, we found that activated HHSCs promote increased adhesion and migration of UM cells. Our findings shed light on the pivotal role of exosomes in pre-metastatic niche construction in the liver.

Optimizing ctDNA: An Updated Review of a Promising Clinical Tool for the Management of Uveal Melanoma.

Uveal melanoma (UM) is the most common primary malignant intraocular tumor in adults. Distant metastasis is common, affecting around 50% of patients. Prognostic accuracy relies on molecular characterization of tumor tissue. In these patients, however, conventional biopsy can be challenging due to the difficulty of obtaining sufficient tissue for the analysis due to the small tumor size and/or post-brachytherapy shrinkage. An alternative approach is liquid biopsy, a non-invasive technique that allows for real-time monitoring of tumor dynamics. Liquid biopsy plays an increasingly prominent role in precision medicine, providing valuable information on the molecular profile of the tumor and treatment response. Liquid biopsy can facilitate early detection and can be used to monitor progression and recurrence. ctDNA-based tests are particularly promising due to their ease of integration into clinical practice. In this review, we discuss the application of ctDNA in liquid biopsies for UM. More specifically, we explore the emerging technologies in this field and the advantages and disadvantages of using different bodily fluids for liquid biopsy. Finally, we discuss the current barriers to routine clinical use of this technique.

TYRP1 directed CAR T cells control tumor progression in preclinical melanoma models.

Despite therapeutic efficacy observed with immune checkpoint blockade in advanced melanoma, many tumors do not respond to treatment, representing a need for new therapies. Here, we have generated chimeric antigen receptor (CAR) T cells targeting TYRP1, a melanoma differentiation antigen expressed on the surface of melanomas, including rare acral and uveal melanomas. TYRP1-targeted CAR T cells demonstrate antigen-specific activation and cytotoxic activity in vitro and in vivo against human melanomas independent of the MHC alleles and expression. In addition, the toxicity to pigmented normal tissues observed with T lymphocytes expressing TYRP1-targeted TCRs was not observed with TYRP1-targeted CAR T cells. Anti-TYRP1 CAR T cells provide a novel means to target advanced melanomas, serving as a platform for the development of similar novel therapeutic agents and as a tool to interrogate the immunobiology of melanomas.

Evaluation of ocular and systemic endpoints after radiation of posterior uveal melanoma - A systematic review and meta-analysis.

Background: Due to the large number of radiotherapeutic options for treatment of posterior uveal melanoma (UM), advantages of each option regarding important clinical endpoints have yet to be determined. Therefore, objective of this systematic review was to analyze the numerous pro- and retrospective cohort studies focusing on the efficacy of different radiotherapeutic options for UM in adults, considering local tumor control, overall survival, visual acuity, eye preservation, metastasis, radiation side effects and dose rates. Methods: The Review was performed based on the Cochrane Handbook of Systematic Reviews. The PubMed database was searched for studies published from January 1st, 2000, up to December 31st, 2021. Research, study selection and critical appraisal was performed by two reviewers. The risk of bias assessment was performed through the revised Cochrane risk of bias tools RoB 2 and ROBINS-I. A meta-analysis of proportions was performed using R (R version 4.1.3, library: meta, procedure: metaprop). This systematic review was registered with Prospero (ID CRD42022311758). Results: Of 4886 studies identified in the database, a total of 20 studies with 4979 participants were included in the qualitative synthesis. Through critical appraisal with ROBINS-I and RoB 2, studies received a 'moderate', 'serious' or 'some concerns' overall risk of bias. Heterogeneity analysis allowed for meta-analysis of proportion of 3 outcome-therapy combinations: local tumor control with I-125 Brachytherapy (proportion: 0.94, CI 95 %: 0.91-0.98), local tumor control with proton therapy (proportion: 0.96, CI 95 %: 0.92-1.00) and eye preservation with I-125 brachytherapy (proportion: 0.91, CI 95 %: 0.88-0.93). This shows local tumor control to be at 94 % with I-125 brachytherapy and at 96 % with proton therapy, as well as an eye preservation rate of 91 % with I-125 brachytherapy. Discussion: The evaluation of outcomes of radiotherapy in UM is limited because of missing data on radiation doses as well as great heterogeneity of study protocols. Radiation therapy outcomes are so far not comparable. Therefore, we recommend for upcoming studies on this topic to provide the biological effective dose (BED) or the equivalent dose in 2 Gy fractions (EQD2) per eye structure, thereby enabling a comparison of outcomes of different forms of radiation therapy.

Three-dimensional cell spheroid culture and cell viability study of uveal melanoma cell line C918 with luteolin treatment.

OBJECTIVE: This study aims to investigate the morphological and histological characteristics of three-dimensional cell spheroids derived from the uveal melanoma (UM) cell line C918 and assess the impact of luteolin on their cell viability. METHODS: C918 cells were cultured in ultra-low adsorption 96-well plates, and morphological changes in C918 three-dimensional cell spheroids were observed over varying time intervals. Histological features of C918 multicellular spheroids cultured in ultra-low adsorption 6-well plates were examined using both HE staining and immunohistochemical staining. The CCK8 reagent was employed to measure the optical density at a 450 nm wavelength after 72-h treatments with varying luteolin concentrations in both two-dimensional and three-dimensional cultured C918 cells. The IC50 values were compared between the two culture conditions. RESULTS: Over time in culture, the volume of C918 three-dimensional cell spheroids gradually increased, and an ischemic- and hypoxic-like region became evident within the spheroids on days 4 to 6 of culture. Histological staining demonstrated positive expression of cell viability marker antibodies (Ki67) and melanoma marker antibodies (MelanA, HMB45, S-100) in the multicellular spheroids from three-dimensional culture. CCK-8 experiments revealed that the IC50 values for luteolin in C918 cells were 183.50 µmol/L in three-dimensional culture and 16.19 µmol/L in two-dimensional culture after 72 h. Three-dimensional cultured C918 cells, treated with varying luteolin concentrations for 72 h, were observed under a microscope. The maximum cross-sectional area showed no statistically significant differences between the groups, but it was reduced in comparison to the control group. CONCLUSION: Three-dimensional cultured C918 cell spheroids exhibit histological characteristics similar to real tumors and are less responsive to luteolin than their two-dimensional counterparts. They offer a valuable model for anti-tumor drug screening.

ZNF197-AS1/miR-425/GABARAPL1 Axis: A Novel Regulatory Mechanism in Uveal Melanoma.

This study investigates the role of the long non-coding RNA (lncRNA) ZNF197-AS1 in uveal melanoma (UM), focusing on its function within a competing endogenous RNA (ceRNA) network. Utilizing the UM-related TCGA dataset, we analyzed the expression levels of ZNF197-AS1 and its correlation with miR-425 and GABARAPL1, an essential autophagy-related gene. Our analysis revealed that ZNF197-AS1 acts as a ceRNA by competitively binding to miR-425, resulting in the upregulation of GABARAPL1. This interaction plays a crucial role in the growth and metastasis of UM. The expression of GABARAPL1 showed a strong correlation with the clinical outcomes of UM patients. Furthermore, in vitro assays confirmed that ZNF197-AS1 impedes UM cell proliferation, migration, and invasion by modulating the miR-425/GABARAPL1 axis. These findings suggest that ZNF197-AS1 can effectively inhibit UM progression through this ceRNA regulatory network. This study provides valuable insights into the molecular mechanisms underlying UM and highlights the potential of targeting the ZNF197-AS1/miR-425/GABARAPL1 axis as a therapeutic strategy for UM.

Malignant melanoma complicated with cataract and secondary glaucoma: A case report.

Uveal melanoma is the most common intraocular malignant tumor in adults. For patients presenting with cataracts and glaucoma, it is recommended to assess whether an intraocular lesion is present as the primary cause. The present study describes the case of a 52-year-old man with primary intraocular malignant melanoma. The patient experienced painless vision loss in the right eye for 1 year, with recent onset of eye swelling and pain in the week prior to seeking medical attention. A slit-lamp examination revealed a shallow anterior chamber in the right eye, a visibly opaque lens and a faint reflection of the tumor surface in the vitreous humor. In addition, the intraocular pressure of this eye was >60 mmHg. Magnetic resonance imaging revealed a large tumor behind the lens measuring 16×18×14 mm. Pathological examination confirmed the diagnosis of malignant melanoma. No BRCA-associated protein-1 somatic mutation was detected, whereas germline mutations of MutL protein homolog 1, RAD54 like, and SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4 were identified. Extensive systemic examination excluded the possibility that the tumors originated from another part of the body. The present case report highlights the crucial role of slit-lamp examination in the detection of ocular tumors. It is advocated that for patients presenting with cataracts, attention should be paid to the possibility of intraocular tumors. Meticulous slit-lamp microscopy may reveal a reflection of the surface of a malignant melanoma, preventing misdiagnosis.

Subretinal Exudation: The First Presentation of Untreated Choroidal Melanomas.

Introduction: This case series aims to present the unusual clinical manifestation of subretinal exudation in patients diagnosed with untreated choroidal melanoma. A total of 886 patients were diagnosed and treated for primary choroidal melanoma between November 2017 and June 2023 at St. Paul's Eye Unit, Royal Liverpool University Hospital, UK. The fundus photographs were screened for lipid exudates by two independent clinical experts. The patients' demographics, clinical manifestations, and imaging features were analysed, whereas the location of exudation was documented with fundus photographs and optical coherence tomography (OCT). The histopathological and genetic results were also analysed in cases with tumour biopsy available. Case Presentations: Eight cases with subretinal exudates were identified (n = 8/886, 0.90%). No gender predilection was noticed (male/female 1:1), whereas the mean age was 51 years (range 39-79). Four patients were asymptomatic at presentation, 2 patients reported reduced visual acuity, and 2 patients presented with photopsia. OCT scans revealed the presence of subretinal fluid and subretinal exudates, while the ultrasound showed medium or low internal reflectivity in 7 out of 8 cases. The biopsy analysis was available in 4 cases, all showing low-risk spindle cell choroidal melanoma with disomy 3. Conclusion: Lipid exudates are an atypical fundoscopic finding in patients with untreated choroidal melanoma. The subretinal location could differentiate them from other retinal vascular conditions and facilitate early diagnosis and intervention. Interestingly, all cases tested cytogenetically were of low metastatic risk; these exudates may, therefore, be a positive clinical prognostic sign.

Description and Characteristics of Ocular Tumor Lysis Syndrome.

Introduction: The aim of the study was to describe and evaluate characteristics of ocular tumor lysis syndrome (OTLS) in eyes with uveal melanoma. Methods: Retrospective chart review of all patients with OTLS at the University of Colorado from 2009 to 2021. Data collected included patient demographics, tumor characteristics, radiation dosimetry, gene expression profiling (GEP), OTLS characteristics, management, and outcomes. Results: Seven eyes of seven patients with uveal melanoma treated with I-125 brachytherapy developed OTLS. Average age was 59 years (range 32-83). Mean apical height was 8.6 mm (range 6-11); mean diameter was 12.7 mm (range 8.5-15.3). All tumors were treated with plaques ≥16 mm in diameter. On presentation, 5/7 tumors had subretinal fluid, and 6/7 had collar-button configuration. OTLS presented as extensive pigment dispersion in the vitreous in all eyes, subretinal pigment and/or retinal detachment in 4/7 eyes, vitreous hemorrhage in 2/7 eyes, and anterior chamber pigment in 3/7 eyes. Four tumors were GEP class 1, two were class 2, and one was unclassified. Biopsy route was trans-scleral in 4/7 eyes and trans-vitreal in 3/7 eyes. OTLS occurred 2-4 weeks after an intraocular procedure in 5/7 eyes. All underwent pars plana vitrectomy. Cytology of the vitreous, obtained in five cases, showed pigment laden macrophages and hemorrhage, but only 1/5 eyes had viable malignant cells. Four eyes were stable at the last follow-up, two were enucleated, and one had no light perception from pigmentary glaucoma. Poor vision (<20/200) occurred in 6/7 cases. Three patients died from metastasis (tumors were GEP class 2, GEP class without subclassification, and no GEP classification performed). Conclusions: OTLS is a rare but devastating complication of uveal melanoma. Common characteristics included large plaque diameter, presence of subretinal fluid, and collar-button shape. The extensively dispersed pigment is typically not malignant. Though poor vision is common, enucleation may be avoided in most eyes through vitreoretinal surgical repair.

Hypoxia-induced BNIP3 facilitates the progression and metastasis of uveal melanoma by driving metabolic reprogramming.

Uveal melanoma (UM) is an aggressive intraocular malignancy derived from melanocytes in the uvea tract of the eye. Up to 50% of patients with UM develop distant metastases which is usually fatal within one year; preventing metastases is therefore essential. Metabolic reprogramming plays a critical role in UM progression and metastasis. However, the metabolic phenotype of UM cells in the hypoxic tumor is not well understood. Here, we report that hypoxia-induced BNIP3 reprograms tumor cell metabolism, promoting their survival and metastasis. In response to hypoxia, BNIP3-mediated mitophagy alleviates mitochondrial dysfunction and enhances mitochondrial oxidative phosphorylation (OXPHOS) while simultaneously reducing mitochondrial reactive oxygen species (mtROS) production. This, in turn, impairs HIF1A/HIF-1α protein stability and inhibits glycolysis. Inhibition of mitophagy significantly suppresses BNIP3-induced UM progression and metastasis in vitro and in vivo. Collectively, these observations demonstrate a novel mechanism whereby BNIP3 promotes UM metabolic reprogramming and malignant progression by mediating hypoxia-induced mitophagy and suggest that BNIP3 could be an important therapeutic target to prevent metastasis in patients with UM.Abbreviations: AOD: average optical density; BNIP3: BCL2/adenovirus E1B interacting protein 3; CQ: chloroquine; CoCl2: cobalt chloride; GEPIA: Gene Expression Profiling Interactive Analysis; HIF1A: hypoxia inducible factor 1, alpha subunit; IHC: immunohistochemistry; mtROS: mitochondrial reactive oxygen species; NAC: N-acetylcysteine; OCR: oxygen consumption rate; OXPHOS: oxidative phosphorylation; ROS: reactive oxygen species; TCGA: The Cancer Genome Atlas; UM: uveal melanoma.

Survey of ocular abnormalities in a population of Turkmen horses.

OBJECTIVE: The aim of this study was to detect and describe ocular abnormalities in a population of Turkmen horses. ANIMALS STUDIED: A total of 55 Turkmen horses (33 mares and 22 stallions) from one herd were evaluated in this study. PROCEDURE(S): Demographic data (Age, Sex, Coat color) were recorded. All animals underwent complete ophthalmic examination. The Schirmer tear test -I (STT-I) was performed for all horses prior to other diagnostic tests. Neuro-ophthalmic examinations (menace response, dazzle reflex, pupillary light reflex, maze test, and visual tracking) were carried out in different lighting situations (bright and dim lights). Slit lamp biomicroscopy, direct and indirect ophthalmoscopy, fluorescein staining, and tonometry were performed for each horse. RESULTS: The mean (standard deviation) age of horses was 5.7 (4.6) years (range of 1-17 years). In total, 18 horses (32.7%) had ocular-related lesions. Cataract, iris hyperpigmentation and corneal edema were the most identified conditions in the horses of this study. CONCLUSIONS: About one-third of studied horses had at least one ocular abnormality. No ocular abnormalities attributed to the distinct cream/gold coat color were identified, which the Turkmen horse is known for.

Survival in uveal melanoma patients is linked to genetic variation at HERC2 SNP rs12913832.

PURPOSE: Uveal melanoma (UM) is a rare disease, with the highest incidence in people with a fair skin and light eyes. Eye colour is largely genetically determined and defined by a set of single nucleotide polymorphisms (SNPs). We set out to determine whether we could identify a SNP that is related to prognosis. DESIGN: We sequenced DNA from peripheral blood mononuclear cells of 392 patients with UM and obtained the genotype of six common eye colour-related SNPs. Clinical and histopathologic tumour characteristics, tumour chromosome status, and patient survival were compared among patients with different genotypes. SUBJECTS: 392 patients who underwent enucleation for UM at the Leiden University Medical Center, Leiden, The Netherlands. METHODS: We isolated DNA from peripheral blood leukocytes of 392 patients with UM and performed sequencing, using six eye colour SNPs from the HIrisPlex-S assay. The genotypes extracted from the sequencing data were uploaded onto the Hirisplex webtool (https://hirisplex.erasmusmc.nl/) for eye colour prediction. We tested the association of eye colour SNPs with tumour characteristics and chromosome aberrations using Pearson's chi-square test and Mann-Whitney U test and survival with Kaplan-Meier curves with log-rank test and Cox regression. MAIN OUTCOME MEASURES: UM-related survival. RESULTS: Of the total cohort of 392 patients with analysable genotype data, 307 (78%) were assigned to have blue eyes, 74 (19%) brown eyes and 11 (3%) could not be assigned to either blue or brown. Patients with a genetically-blue eye colour had a worse survival (p = 0.04). This was related to one genotype: patients with the G/G genotype of rs12913832 (HERC2) which codes for blue eye colour had a worse prognosis (p = 0.017), which was related to more often having high-risk tumours (monosomy of chromosome 3, p = 0.04) than patients with an A/G or A/A genotype. CONCLUSION: The G/G genotype of rs12913832 (HERC2), which is related to blue eye colour, is not only a genetic factor related to the risk to develop a UM, but is also linked to a worse prognosis, due to an association with a higher risk of developing a high-risk UM (carrying monosomy of chromosome 3).

Geographic Patterns of Ocular Oncologist Supply and Patient Demand for Uveal Melanoma Treatment in the United States: A Supply and Demand Analysis.

Purpose: To study geographic patterns of supply and demand for uveal melanoma and other ocular oncology healthcare by ocular oncology physicians in the United States. Methods: Google search interest data was obtained through trends.google.com. The combined-state density of ocular oncology physicians was calculated by dividing the number of practicing ocular oncologists in each state and its surrounding states by the state population. Relative search volume (RSV) values were divided by ocular oncology physician density to calculate the Google relative demand index (gRDI) for each state. Medicare (mRDI) and IRIS® Registry (iRDI) relative demand indices were calculated using prevalence data obtained through the Vision and Eye Health Surveillance System (VEHSS). Data from the US Census Bureau and Centers for Disease Control (CDC) databases were also utilized to analyze associations with poverty rates, percent living in urban or rural areas, vision screening rates, and ocular neoplasm rates. Results: Alabama showed the highest RSV (100), while the lowest was reported in New Mexico (20). Vermont had the highest density of combined-state ocular oncology ophthalmologists (1.85 per 100,000 residents). New Mexico had the lowest RDI (0.013 gRDI, 0.015 mRDI, 0.018 iRDI) with 32 combined-state ocular oncologists and a population of 2,114,371. Ocular neoplasm prevalence rates ranged between 1.32% and 5.40% and significantly correlated with RSV. Single-state gRDI correlated with rural status and negatively correlated with urban areas (≥50,000 individuals). Single-state ophthalmologist density correlated positively with percent living in urban areas and vision screening rates, and negatively with rural status. Conclusion: This study uncovered significant heterogeneity in the geographical distribution of ocular oncology physicians and RDI throughout the United States, highlighting potential undersupply scenarios. This may guide efforts to increase ocular oncology physician and surgeon availability in areas of need.

A cuproptosis-related prognostic signature for guiding clinical diagnosis and treatment in uveal melanoma patients.

Background: Cuproptosis, one of the most recently discovered forms of cell death, is induced by the disruption of copper binding to the mitochondrial respiratory acylation components. However, the mechanism underlying cuproptosis in uveal melanoma (UM) has not yet been adequately studied. Methods: RNA and clinical data were obtained from The Cancer Genome Atlas (TCGA) database. Differentially expressed cuproptosis-related genes were identified by R software. A prognostic signature was constructed by applying LASSO regression and Cox regression models. The associations between the signature and the immune microenvironment, overall survival, and drug sensitivity were studied. In addition, qPCR and Western blotting were performed on UM cells and RPE cell lines to verify the expression levels of the genes encoding dihydrolipoamide dehydrogenase (DLD) and dihydrolipoamide S-succinyltransferase (DLST) in UM cases. Results: Using a cuproptosis-related prognostic signature, UM samples were classified into high- and low-risk groups. A significant difference in overall survival between the two risk groups was evident. Receiver operating characteristic curves demonstrated that the signature is a reliable predictor of prognosis. Immune cell infiltration, drug sensitivity, and immune checkpoint expression were analysed. Significant immune difference between the two high-risk groups was found, and the high expression of immune checkpoints in high-risk groups suggests significant immunotherapy potential. In addition, drug sensitivity analysis experiments suggest that erlotinib may be a potential treatment for high-risk patients. The results of in vitro experiments confirmed that DLD and DLST had higher expression levels in UM cell lines. Conclusions: The prognostic signature developed in this study is a reliable biomarker for predicting the prognosis of UM and may serve as a tool for personalised treatment of patients with UM.

Identification of feature genes and molecular mechanisms involved in cell communication in uveal melanoma through analysis of single­cell sequencing data.

Uveal melanoma (UM) is a highly metastatic cancer with resistance to immunotherapy. The present study aimed to identify novel feature genes and molecular mechanisms in UM through analysis of single-cell sequencing data. For this purpose, data were downloaded from The Cancer Genome Atlas and National Center for Biotechnology Information Gene Expression Omnibus public databases. The statistical analysis function of the CellPhoneDB software package was used to analyze the ligand-receptor relationships of the feature genes. The Metascape database was used to perform the functional annotation of notable gene sets. The randomForestSRC package and random survival forest algorithm were applied to screen feature genes. The CIBERSORT algorithm was used to analyze the RNA-sequencing data and infer the relative proportions of the 22 immune-infiltrating cell types. In vitro, small interfering RNAs were used to knockdown the expression of target genes in C918 cells. The migration capability and viability of these cells were then assessed by gap closure and Cell Counting Kit-8 assays. In total, 13 single-cell sample subtypes were clustered by t-distributed Stochastic Neighbor Embedding and annotated by the R package, SingleR, into 7 cell categories: Tissue stem cells, epithelial cells, fibroblasts, macrophages, natural killer cells, neurons and endothelial cells. The interactions in NK cells|Endothelial cells, Neurons|Endothelial cells, CD74_APP, and SPP1_PTGER4 were more significant than those in the other subsets. T-Box transcription factor 2, tropomyosin 4, plexin D1 (PLXND1), G protein subunit α I2 (GNAI2) and SEC14-like lipid binding 1 were identified as the feature genes in UM. These marker genes were found to be significantly enriched in pathways such as vasculature development, focal adhesion and cell adhesion molecule binding. Significant correlations were observed between key genes and immune cells as well as immune factors. Relationships were also observed between the expression levels of the key genes and multiple disease-related genes. Knockdown of PLXND1 and GNAI2 expression led to significantly lower viability and gap closure rates of C918 cells. Therefore, the results of the present study uncovered cell communication between endothelial cells and other cell types, identified innovative key genes and provided potential targets of gene therapy in UM.

Clinical and pathological characterization of tebentafusp-associated skin toxicity: A cohort study with 33 patients.

BACKGROUND: Tebentafusp is a novel treatment for patients with metastatic uveal melanoma and often causes cutaneous side effects. OBJECTIVES: The aim of this study was to better characterize these heterogenous cutaneous side effects. METHODS: This prospective cohort study evaluated all patients from a tertiary hospital center who were treated with tebentafusp between January 2019 and June 2023 clinically and assessed skin biopsies histologically. RESULTS: In total, 33 patients were analyzed. Skin toxicity was observed in 78.8% of patients and was classified into 5 clinical categories: (1) symmetrical erythematous patches (83.8%), (2) hemorrhagic macules (11.8%), (3) urticarial lesions (7.4%), (4) bullous lesions (1.5%), and (5) skin (8.5%) and hair depigmentation (11.4%). Histopathologic features were focal lymphocytic interface dermatitis with epidermal infiltration of CD8-positive lymphocytes. Patients with skin reactions had a significantly longer median overall survival compared to patients without any cutaneous events (34 versus 4 months, P < .001). LIMITATION: Monocentric study with a limited number of patients. CONCLUSION: Tebentafusp frequently induces cutaneous reactions. Pathogenesis is likely due to binding of tebentafusp to stimulated melanocytes in the skin, followed by infiltration and activation of lymphocytes. Development of treatment-induced skin reactions may be associated with survival benefits.