Hepatic and Overall Progression-Free Survival After Percutaneous Hepatic Perfusion (PHP) as First-Line or Second-Line Therapy for Metastatic Uveal Melanoma.

BACKGROUND: Uveal melanoma often metastasizes to the liver, portending a poor prognosis. Melphalan/hepatic delivery system (HDS) via percutaneous hepatic perfusion (PHP) is a minimally invasive means of circulating high-dose chemotherapy through the affected liver. This study evaluated melphalan/HDS use as either first-line or second-line treatment to guide treatment sequencing. PATIENTS AND METHODS: A retrospective review included patients with hepatic-dominant metastatic uveal melanoma who underwent melphalan/HDS treatment via PHP from 2008 to 2023. RESULTS: A total of 30 patients were identified; 53.3% female, with a median age of 63.5 years (37-78 years). Median follow-up time was 14.5 months. First-line therapies included melphalan/HDS (n = 17), liver-directed (n = 7), and immunotherapy (n = 6). Second-line therapies included melphalan/HDS (n = 6), immunotherapy (n = 5), and liver-directed (n = 3). Median hepatic progression-free survival (hPFS) for first-line melphalan/HDS, immunotherapy, and liver-directed therapy was 17.6/8.8/9.2 months, respectively (P = 0.002). Median hPFS for second-line melphalan/HDS, immunotherapy, and liver-directed therapy was not reached/14.7/7.5 months, respectively (P < 0.001). Median overall PFS for first-line melphalan/HDS, immunotherapy, and liver-directed therapy was 15.4/8.8/9.2 months, respectively (P = 0.04). Median overall PFS for second-line melphalan/HDS, immunotherapy, and liver-directed therapy was 22.2/14.7/7.5 months, respectively (P = 0.001). CONCLUSIONS: Melphalan/HDS via PHP for metastatic uveal melanoma to the liver was found to have significantly improved hPFS and overall PFS when used as first-line therapy compared with immunotherapy or liver-directed therapy. PHP continued to demonstrate improved hPFS and PFS when used as second-line therapy compared with second-line immunotherapy or liver-directed therapy.

TRP channel-related LncRNAs, AC092535.4 and LINC01637, as novel prognostic biomarkers for uveal melanoma.

Introduction: Transient receptor potential (TRP) channels function as cellular sensors with a broad impact, and their dysregulation is linked to numerous cancers. The influence of TRP channel-related long noncoding RNAs (TCRLs) on uveal melanoma (UM) remains poorly understood. Methods: We employed bioinformatics to examine the RNA-seq data and relevant clinical information of UM in the TCGA databases. By implementing coexpression analysis, we identified differentially expressed TCRLs. Using univariate Cox regression analysis, selection operator (LASSO) algorithm and stepwise regression, five key prognostic biomarkers were chosen. The high- and low-risk groups were divided based on the risk scores. Afterwards, the prediction performance of the signature was evaluated by receiver operating characteristic (ROC) curve and Kaplan-Meier (K-M) survival analysis. The functional enrichment analysis of TCRLs was also investigated. Following that, we examined immune cell infiltration, immune checkpoint expression, and tumor immune microenvironment between patients in high and low risk groups. TCRLs were validated using Random forests and multifactor Cox analysis. Candidate biomarkers were identified and screened. Finally, the effects of the candidate biomarkers on the proliferation, migration and invasion of UM cells were detected by CCK-8 assay, migration assay and perforation invasion assay. Results: The risk score generated by five TCRLs demonstrated robust predictive power. The high-risk group exhibited a poorer prognosis, increased immune cell infiltration, and an active tumor immune microenvironment compared to the low-risk group. Furthermore, two TCRLs of risk score, AC092535.4 and LINC01637, were screened to multiplex modelling. The in vitro experiments demonstrated that UM cells were suppressed following AC092535.4 or LINC01637 knockdown. Discussion: Two TCRLs, AC092535.4 and LINC01637, serve as novel prognostic biomarkers for uveal melanoma and may present potential therapeutic targets.

Genome-Wide Methylation Patterns in Primary Uveal Melanoma: Development of MethylSig-UM, an Epigenomic Prognostic Signature to Improve Patient Stratification.

Despite studies highlighting the prognostic utility of DNA methylation in primary uveal melanoma (pUM), it has not been translated into a clinically useful tool. We sought to define a methylation signature to identify newly diagnosed individuals at high risk for developing metastasis. Methylation profiling was performed on 41 patients with pUM with stage T2-T4 and at least three years of follow-up using the Illumina Infinium HumanMethylation450K BeadChip (N = 24) and the EPIC BeadChip (N = 17). Findings were validated in the TCGA cohort with known metastatic outcome (N = 69). Differentially methylated probes were identified in patients who developed metastasis. Unsupervised consensus clustering revealed three epigenomic subtypes associated with metastasis. To identify a prognostic signature, recursive feature elimination and random forest models were utilized within repeated cross-validation iterations. The 250 most commonly selected probes comprised the final signature, named MethylSig-UM. MethylSig-UM could distinguish individuals with pUM at diagnosis who develop future metastasis with an area under the curve of ~81% in the independent validation cohort, and remained significant in Cox proportional hazard models when combined with clinical features and established genomic biomarkers. Altered expression of immune-modulating genes were detected in MethylSig-UM positive tumors, providing clues for pUM resistance to immunotherapy. The MethylSig-UM model is available to enable additional validation in larger cohort sizes including T1 tumors.

Shear-wave elastographic imaging in choroidal melanomas: clinical and hemodynamic correlations.

PURPOSE: This study evaluated the role of shear wave elastography imaging (SWEΙ) in uveal melanomas and the associations between SWEI and clinical and hemodynamic findings. STUDY DESIGN: Prospective, clinical study METHODS: Twelve patients with uveal melanomas, scheduled to undergo Ru-106 brachytherapy, were prospectively recruited from the Department of Ophthalmology of the University Hospital of Heraklion (September-December 2022). B-mode, hemodynamic and SWEI ultrasonography examinations were performed with the HiScan (OPTIKON 2000) and the LOGIQ E9 (GE Healthcare) sonographic systems, respectively. Differences in SWEI scores (kPa) between tumor (TS) and adjacent non-affected choroid (CS), as well as between TS and orbital fat (FS) were examined. Correlations between SWEI and intra-tumoral hemodynamic parameters, including peak systolic and end diastolic velocities and resistivity index (RI) were also examined. RESULTS: TS was significantly correlated with intra-tumoral RI (Pearson's bivariate correlation coefficient 0.681, p=0.015) and with maximal tumor height (Pearson's bivariate correlation coefficient 0.620, p=0.031). TS was significantly higher than both FS and CS scores (paired-samples t-test, p=0.003 and p=0.006, respectively). CONCLUSIONS: SWEI score is applicable as a quantitative biomechanical marker in the assessment of choroidal melanoma. Choroidal melanomas are stiffer than both adjacent choroid and orbital fat. Moreover, choroidal melanomas with higher RI as well as those with higher apical elevations display higher SWEI scores.

Senescent endothelial cells promote liver metastasis of uveal melanoma in single-cell resolution.

BACKGROUND: Uveal melanoma (UM), the most common adult intraocular tumor, is characterized by high malignancy and poor prognosis in advanced stages. Angiogenesis is critical for UM development, however, not only the role of vascular endothelial dysfunction in UM remains unknown, but also their analysis at the single-cell level has been lacking. A comprehensive analysis is essential to clarify the role of the endothelium in the development of UM. METHODS: By using single-cell RNA transcriptomics data of 11 cases of primary and liver metastasis UM, we analyzed the endothelial cell status. In addition, we analyzed and validated ECs in the in vitro model and collected clinical specimens. Subsequently, we explored the impact of endothelial dysfunction on UM cell migration and explored the mechanisms responsible for the endothelial cell abnormalities and the reasons for their peripheral effects. RESULTS: UM metastasis has a significantly higher percentage of vascular endothelial cells compared to in situ tumors, and endothelial cells in metastasis show significant senescence. Senescent endothelial cells in metastatic tumors showed significant Krüppel-like factor 4 (KLF4) upregulation, overexpression of KLF4 in normal endothelial cells induced senescence, and knockdown of KLF4 in senescent endothelium inhibited senescence, suggesting that KLF4 is a driver gene for endothelial senescence. KLF4-induced endothelial senescence drove tumor cell migration through a senescence-associated secretory phenotype (SASP), of which the most important component of the effector was CXCL12 (C-X-C motif chemokine ligand 12), and participated in the composition of the immunosuppressive microenvironment. CONCLUSION: This study provides an undesirable insight of senescent endothelial cells in promoting UM metastasis.

[Epigenetic markers of choroidal melanoma]. / Epigeneticheskie markery melanomy khorioidei.

MicroRNAs (miRNAs) are short non-coding RNAs (18-25 nucleotides in length) that are important participants in the regulation of gene expression. In 2003, their active role in oncogenesis was demonstrated. In 2008, the first report on the isolation of miRNAs from uveal melanoma (UM) tissue was published. Four years later (2012), the presence of miRNAs in the plasma of patients with this category was shown. To date, changes in the expression level of 100 miRNAs in the plasma of cancer patients (with cancer of various localizations) out of the 2654 miRNAs described in mirbase.org have been proven. In the plasma of patients with UM, changes in the expression of only 13 miRNAs have been confirmed. As a rule, studies were conducted in patients at the stage of hematogenous metastasis of UM. PURPOSE: This study analyzed the expression pattern of miRNA-223 and miRNA-126 in patients with localized choroidal melanoma (CM) taking into account biometric parameters in the absence of metastases. MATERIAL AND METHODS: Blood plasma of 84 patients with M0N0 CM aged 35-86 years (mean age 63.4±1.2 years) was investigated. The basis for the diagnosis of CM was the results of ophthalmological examination, optical coherence tomography, and ultrasound scanning. In all cases, the absence of metastases was proven (using computed tomography or magnetic resonance imaging). Control - plasma of 28 volunteers (mean age 62.9±1.42 years, age range 45-78 years), who did not have tumoral, autoimmune, or chronic inflammatory processes. The expression levels of miRNAs circulating in blood plasma were determined by real-time polymerase chain reaction. RESULTS: An increase in the expression levels of miRNA-223 and miRNA-126 in the plasma of all 84 patients with CM was confirmed compared to the control group. Features of the miRNA expression pattern that emerged with changes in the tumor's quantitative parameters were identified. CONCLUSION: Evaluation of the levels of miRNA-223 and miRNA-126 in the blood plasma of patients with CM can be used in clinical practice to clarify the diagnosis of CM, as well as to predict the development of hematogenous metastases.

Ultrasensitive detection of uveal melanoma using [18F]AlF-NOTA-PRGD2 PET imaging.

BACKGROUND: Uveal melanoma (UM) is the most common primary intraocular tumor in adults, and early detection is critical to improve the clinical outcome of this disease. In this study, the diagnostic effectiveness of [18F]AlF-NOTA-PRGD2 (an investigational medicinal product) positron emission tomography (PET) imaging in UM xenografts and UM patients were evaluated. The cell uptake, cell binding ability and in vitro stability of [18F]AlF-NOTA-PRGD2 were evaluated in 92-1 UM cell line. MicroPET imaging and biodistribution study of [18F]AlF-NOTA-PRGD2 were conducted in 92-1 UM xenografts. Then, UM patients were further recruited for evaluating the diagnostic effectiveness of [18F]AlF-NOTA-PRGD2 PET imaging (approval no. NCT02441972 in clinicaltrials.gov). In addition, comparison of [18F]AlF-NOTA-PRGD2 and 18F-labelled fluorodeoxyglucose ([18F]FDG) PET imaging in UM xenografts and UM patients were conducted. RESULTS: The in vitro data showed that [18F]AlF-NOTA-PRGD2 had a high cell uptake, cell binding ability and in vitro stability in 92-1 UM cell line. The in vivo data indicated that 92-1 UM tumors were clearly visualized with the [18F]AlF-NOTA-PRGD2 tracer in the subcutaneous and ocular primary UM xenografts model at 60 min post-injection. And the tumor uptake of the tracer was 2.55 ± 0.44%ID/g and 1.73 ± 0.15%ID/g at these two tissue locations respectively, at 7 days after animal model construction. The clinical data showed that tumors in UM patients were clearly visualized with the [18F]AlF-NOTA-PRGD2 tracer at 60 min post-injection. In addition, [18F]AlF-NOTA-PRGD2 tracer showed higher sensitivity and specificity for PET imaging in UM xenografts and UM patients compared to [18F]FDG tracer. CONCLUSION: [18F]AlF-NOTA-PRGD2 PET imaging may be a more preferred approach in the diagnosis of primary UM compared to [18F]FDG PET imaging. Additionally, due to the high tumor-to-background ratio, [18F]AlF-NOTA-PRGD2 PET imaging seems also to be applicable for the diagnosis of UM patients with liver metastasis. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02441972, Registered 1 January 2012, https://clinicaltrials.gov/study/NCT02441972 .

Radiation and systemic immunotherapy for metastatic uveal melanoma: a clinical retrospective review.

Introduction: Metastatic uveal melanoma (mUM) is a difficult to treat disease. The liver is the primary site of metastasis in most patients, though uveal melanoma spreads widely in advanced disease. The only FDA approved immunotherapy medication for metastatic uveal melanoma is the HLA-A02:01 restricted bispecific T cell engager drug, Tebentafusp. Checkpoint inhibitor strategies and combination approaches have been tried with some limited success. We describe our experience treating patients at the University of Minnesota. Methods: Patients were included if they had biopsy-confirmed mUM. Twenty-five (25) patients meeting the criteria were identified. Medical records were reviewed and data extracted for patient baseline characteristics and response to treatments. Results: Median time to metastasis from the time of local therapy to the eye was 14.2 months (IQR; 9.3-22.0), and first site of metastasis was liver in 92% of patients. Two patients (8%) did not receive systemic therapy or radiation therapy for metastatic disease. Twenty-three (92%) patients received systemic therapy, 13 patients (52%) received ipilimumab-nivolumab as the first-line, while 4 patients (16%) received pembrolizumab. Landmark survival analysis by receipt of systemic therapy and radiation therapy treatments within 6 months of biopsy confirmed diagnosis is shown. Twenty patients (80%) received systemic therapy within 6 months of mUM diagnosis. Thirteen patients (52%) received liver directed radiation therapy within 6 months of mUM diagnosis. Discussion: Within our cohort, there was no overall survival benefit for patients receiving treatment of metastatic disease within 6 months of mUM diagnosis, versus those electing later or no treatment at all. There was remarkable clinical activity of ipilimumab and nivolumab in a subset of patients with mUM, in agreement with prior studies, and metastatic PD-L1 positive tumors were associated with a prolonged survival.

Single cell RNA-sequencing in uveal melanoma: advances in heterogeneity, tumor microenvironment and immunotherapy.

Uveal melanoma (UM) is a highly aggressive and fatal tumor in the eye, and due the special biology of UM, immunotherapy showed little effect in UM patients. To improve the efficacy of immunotherapy for UM patients is of great clinical importance. Single-cell RNA sequencing(scRNA-seq) provides a critical perspective for deciphering the complexity of intratumor heterogeneity and tumor microenvironment(TME). Combing the bioinformatics analysis, scRNA-seq could help to find prognosis-related molecular indicators, develop new therapeutic targets especially for immunotherapy, and finally to guide the clinical treatment options.

Uveal melanoma distant metastasis prediction system: A retrospective observational study based on machine learning.

Uveal melanoma (UM) patients face a significant risk of distant metastasis, closely tied to a poor prognosis. Despite this, there is a dearth of research utilizing big data to predict UM distant metastasis. This study leveraged machine learning methods on the Surveillance, Epidemiology, and End Results (SEER) database to forecast the risk probability of distant metastasis. Therefore, the information on UM patients from the SEER database (2000-2020) was split into a 7:3 ratio training set and an internal test set based on distant metastasis presence. Univariate and multivariate logistic regression analyses assessed distant metastasis risk factors. Six machine learning methods constructed a predictive model post-feature variable selection. The model evaluation identified the multilayer perceptron (MLP) as optimal. Shapley additive explanations (SHAP) interpreted the chosen model. A web-based calculator personalized risk probabilities for UM patients. The results show that nine feature variables contributed to the machine learning model. The MLP model demonstrated superior predictive accuracy (Precision = 0.788; ROC AUC = 0.876; PR AUC = 0.788). Grade recode, age, primary site, time from diagnosis to treatment initiation, and total number of malignant tumors were identified as distant metastasis risk factors. Diagnostic method, laterality, rural-urban continuum code, and radiation recode emerged as protective factors. The developed web calculator utilizes the MLP model for personalized risk assessments. In conclusion, the MLP machine learning model emerges as the optimal tool for predicting distant metastasis in UM patients. This model facilitates personalized risk assessments, empowering early and tailored treatment strategies.

Prognostic value of clinical and radiomic parameters in patients with liver metastases from uveal melanoma.

Approximately every second patient with uveal melanoma develops distant metastases, with the liver as the predominant target organ. While the median survival after diagnosis of distant metastases is limited to a year, yet-to-be-defined subgroups of patients experience a more favorable outcome. Therefore, prognostic biomarkers could help identify distinct risk groups to guide patient counseling, therapeutic decision-making, and stratification of study populations. To this end, we retrospectively analyzed a cohort of 101 patients with newly diagnosed hepatic metastases from uveal melanoma by using Cox-Lasso regression machine learning, adapted to a high-dimensional input parameter space. We show that substantial binary risk stratification can be performed, based on (i) clinical and laboratory parameters, (ii) measures of quantitative overall hepatic tumor burden, and (iii) radiomic parameters. Yet, combining two or all three domains failed to improve prognostic separation of patients. Additionally, we identified highly relevant clinical parameters (including lactate dehydrogenase, thrombocyte counts, aspartate transaminase, and the metastasis-free interval) at first diagnosis of metastatic disease as predictors for time-to-treatment failure and overall survival. Taken together, the risk stratification models, built by our machine-learning algorithm, identified a comparable and independent prognostic value of clinical, radiological, and radiomic parameters in uveal melanoma patients with hepatic metastases.

Clinical Characteristics and Special Considerations in the Management of Rare Melanoma Subtypes.

Rare histologic subtypes of melanoma, including acral, mucosal, uveal, and desmoplastic melanomas, only make up 5% of all diagnosed melanomas and are often underrepresented in large, randomized trials. Recent advancements in systemic therapy have shown marked improvement in pathologic response rates, improving progression-free and overall survival among cutaneous melanoma patients, but there are limited data to demonstrate improved survival among rarer subtypes of melanoma. Acral melanoma has a poor response to immunotherapy and is associated with worse survival. Mucosal melanoma has a large variability in its presentation, a poor prognosis, and a low mutational burden. Uveal melanoma is associated with a high rate of liver metastasis; recent adoption of infusion and perfusion therapies has demonstrated improved survival among these patients. Desmoplastic melanoma, a high-risk cutaneous melanoma, is associated with high locoregional recurrence rates and mutational burden, suggesting this melanoma may have enhanced response to immunotherapy. While these variants of melanoma represent distinct disease entities, this review highlights the clinicopathologic characteristics and treatment recommendations for each of these rare melanomas and highlights the utility of modern therapies for each of them.

Erdafitinib promotes ferroptosis in human uveal melanoma by inducing ferritinophagy and lysosome biogenesis via modulating the FGFR1/mTORC1/TFEB signaling axis.

Uveal melanoma (UM) is a rare yet lethal primary intraocular malignancy affecting adults. Analysis of data from The Cancer Genome Atlas (TCGA) database revealed that FGFR1 expression was increased in UM tumor tissues and was linked to aggressive behavior and a poor prognosis. This study assessed the anti-tumor effects of Erdafitinib, a selective pan-FGFR inhibitor, in both in vitro and in vivo UM models. Erdafitinib exhibited a robust anti-cancer activity in UM through inducing ferroptosis in the FGFR1-dependent manner. Transcriptomic data revealed that Erdafitinib mediated its anti-cancer effects via modulating the ferritinophagy/lysosome biogenesis. Subsequent research revealed that Erdafitinib exerted its effects by reducing the expression of FGFR1 and inhibiting the activity of mTORC1 in UM cells. Concurrently, it enhanced the dephosphorylation, nuclear translocation, and transcriptional activity of TFEB. The aggregation of TFEB in nucleus triggered FTH1-dependent ferritinophagy, leading to lysosomal activation and iron overload. Conversely, the overexpression of FGFR1 served to mitigate the effects of Erdafitinib on ferritinophagy, lysosome biogenesis, and the activation of the mTORC1/TFEB signaling pathway. In vivo experiments have convincingly shown that Erdafitinib markedly curtails tumor growth in an UM xenograft mouse model, an effect that is closely correlated with a decrease in FGFR1 expression levels. The present study is the first to demonstrate that Erdafitinib powerfully induces ferroptosis in UM by orchestrating the ferritinophagy and lysosome biogenesis via modulating the FGFR1/mTORC1/TFEB signaling. Consequently, Erdafitinib emerges as a strong candidate for clinical trial investigation, and FGFR1 emerges as a novel and promising therapeutic target in the treatment of UM.

Efficacy and safety of tebentafusp in patients with metastatic uveal melanoma: A systematic review and meta-analysis.

Patients with metastatic uveal melanoma (mUM) have a poor prognosis, and few appropriate medications are available. Tebentafusp is approved by the Food and Drug Administration for mUM recently. However, the real efficacy and safety of tebentafusp are still unclear. We searched PubMed, Embase, and Cochrane Library from inception to March 20, 2024. The research was reported based on the preferred reporting items for systematic reviews and meta-analysis guidelines. We used random effects models to aggregate data on the response rates and adverse events of tebentafusp therapy. Six studies met the inclusion criteria with a total sample of 589 participants. The pooled objective response rate was 0.08 (95% CI: 0.05-0.12), and pooled disease control rate was 0.51 (95% CI: 0.44-0.57). The overall incidence was 0.99 (95% CI: 0.95-1.00) for any grade adverse events, 0.50 (95% CI: 0.41-0.59) for grade 3-4 adverse events, and 0.01 (95% CI: 0-0.03) for discontinuation due to adverse events. Tebentafusp exhibits promising treatment outcomes for mUM patients. Although accompanied with a common occurrence of adverse events, which can typically be managed and controlled. Future research is necessary for substantiating these findings and refining guidelines for management of mUM.

Electroporation with Calcium or Bleomycin: First Application in an In Vivo Uveal Melanoma Patient-Derived Xenograft Model.

Uveal melanoma (UM) represents a rare tumor of the uveal tract and is associated with a poor prognosis due to the high risk of metastasis. Despite advances in the treatment of UM, the mortality rate remains high, dictating an urgent need for novel therapeutic strategies. The current study introduces the first in vivo analysis of the therapeutic potential of calcium electroporation (CaEP) compared with electrochemotherapy (ECT) with bleomycin in a patient-derived xenograft (PDX) model based on the chorioallantoic membrane (CAM) assay. The experiments were conducted as monotherapy with either 5 or 10 mM calcium chloride or 1 or 2.5 µg/mL bleomycin in combination with EP or EP alone. CaEP and ECT induced a similar reduction in proliferative activity, neovascularization, and melanocytic expansion. A dose-dependent effect of CaEP triggered a significant induction of necrosis, whereas ECT application of 1 µg/mL bleomycin resulted in a significantly increased apoptotic response compared with untreated tumor grafts. Our results outline the prospective use of CaEP and ECT with bleomycin as an adjuvant treatment of UM, facilitating adequate local tumor control and potentially an improvement in metastatic and overall survival rates.

Association Between Uveal Melanoma and Allostatic Load.

BACKGROUND/AIM: Allostatic load (AL) is a measure of chronic stress that is associated with worse cancer outcomes. The purpose of this retrospective cohort study was to investigate the relationship between AL and uveal melanoma (UM) clinical features. PATIENTS AND METHODS: AL score was calculated as a composite of ten biomarkers in 111 patients with UM from the University of Illinois Hospital. One point was assigned to an AL score for each biomarker based on predetermined cutoff values. Linear and logistic regression analyses evaluated the relationship between AL score and several tumor clinical characteristics. RESULTS: High AL score had a significant relationship with extraocular extension (p=0.015). There was also a significant difference in mean blood glucose levels between the different tumor size groups (p=0.029). Higher AL scores also had a trend of being associated with a smaller tumor size (p=0.069). CONCLUSION: AL score was significantly associated with the presence of extraocular extension for uveal melanoma, while the smallest tumor size group was associated with the highest blood glucose level. No other significant correlations were found between AL and other clinical features of UM. The relationship between AL score and extraocular extension warrants further investigation. Additional research is needed to evaluate socioeconomic factors and their effect on the relationship between chronic stress and the clinical features of UM.

Impact of Driver Mutations on Metastasis-Free Survival in Uveal Melanoma: A Meta-Analysis.

The prognosis of uveal melanoma is significantly influenced by the risk of metastasis, which varies according to clinical and genetic features. Driver mutations can predict the likelihood of disease progression and survival, although the data in the literature are inconsistent. This meta-analysis aimed to evaluate the prognostic significance of driver mutations, including GNAQ, GNA11, BAP1, and SF3B1, in the advancement of uveal melanoma. A comprehensive search of databases yielded relevant studies, and data from 13 studies (848 eyes) were synthesized to assess the impact of these mutations on metastasis-free survival. The BAP1 mutation and negative immunohistochemistry were associated with a higher risk of metastasis (logHR = 1.44, 95% CI 1.05-1.83). GNAQ, GNA11, and SF3B1 mutations did not show a significant increase in risk. In summary, BAP1 has proven to reliably predict the likelihood of disease progression in uveal melanoma, while further studies are needed to establish the significance of other driver mutations.

The elusive BAP1 mutation in pediatric melanocytic tumors.

Cutaneous BAP1-inactivated melanocytomas (BIM) are melanocytic proliferations defined histopathologically by an epithelioid, predominantly dermal melanocytic proliferation with loss of BAP1, and have been largely characterized in adult patients but less well-described in pediatric cohorts. BIM share overlapping histological features with those seen in Spitz nevi; however, unlike Spitz nevi, the majority of BIM carry both BAP1 and BRAFV600E mutations. This study investigated the potential overlap of BIMs with pediatric Spitz nevi by performing immunohistochemical staining of BAP1 and BRAFV600E on pediatric melanocytic tumors with banal Spitz and dermal features. None of the stained tumors in our study exhibited the concurrent BAP1 loss and BRAFV600E positivity that are characteristic of adult BIM, suggesting that this is a low-frequency mutation among banal tumors in the pediatric population.

Condensation domain editing of the FR900359 assembly line yields a novel analog amenable to late-stage functionalization.

The natural product FR900359 (FR) has generated significant attention lately, due to its characteristics as potent and selective inhibitor of Gq/11 mediated signal transduction of associated G protein-coupled receptors (GPCRs). This makes FR both a widely used pharmacological tool compound and a lead molecule for targeted cancer therapy. The exploration of structure-activity-relationship (SAR) of the scaffold by total synthesis has been complicated by its structural complexity and its incompatibility with standard approaches of solid-phase peptide synthesis. Options for late-stage functionalization of FR are limited due to a lack of tractable functional groups. Here we present a mixed approach combining i) genetic engineering of the FR-assembly line in Chromobacterium vaccinii, to obtain a novel FR analog featuring a primary amine, with ii) its subsequent synthetic modification and biological profiling for further SAR exploration of the FR scaffold.

Geometrical accuracy of magnetic resonance imaging for ocular proton therapy planning.

Background & purpose: Magnetic resonance imaging (MRI) is increasingly used in treatment preparation of ocular proton therapy, but its spatial accuracy might be limited by geometric distortions due to susceptibility artefacts. A correct geometry of the MR images is paramount since it defines where the dose will be delivered. In this study, we assessed the geometrical accuracy of ocular MRI. Materials & methods: A dedicated ocular 3 T MRI protocol, with localized shimming and increased gradients, was compared to computed tomography (CT) and X-ray images in a phantom and in 15 uveal melanoma patients. The MRI protocol contained three-dimensional T2-weighted and T1-weighted sequences with an isotropic reconstruction resolution of 0.3-0.4 mm. Tantalum clips were identified by three observers and clip-clip distances were compared between T2-weighted and T1-weighted MRI, CT and X-ray images for the phantom and between MRI and X-ray images for the patients. Results: Interobserver variability was below 0.35 mm for the phantom and 0.30(T1)/0.61(T2) mm in patients. Mean absolute differences between MRI and reference were below 0.27 ± 0.16 mm and 0.32 ± 0.23 mm for the phantom and in patients, respectively. In patients, clip-clip distances were slightly larger on MRI than on X-ray images (mean difference T1: 0.11 ± 0.38 mm, T2: 0.10 ± 0.44 mm). Differences did not increase at larger distances and did not correlate to interobserver variability. Conclusions: A dedicated ocular MRI protocol can produce images of the eye with a geometrical accuracy below half the MRI acquisition voxel (<0.4 mm). Therefore, these images can be used for ocular proton therapy planning, both in the current model-based workflow and in proposed three-dimensional MR-based workflows.