Immunotherapy for Uveal Melanoma - Current Knowledge and Perspectives

Multifaceted roles of PD-1 in tumorigenesis: From immune checkpoint to tumor cell-intrinsic function

Programmed cell death 1 (PD-1), a key immune checkpoint receptor, has been extensively studied for its role in regulating immune responses in cancer. However, recent research has unveiled a complex and dual role for PD-1 in tumorigenesis. While PD-1 is traditionally associated with immune cells, this article explores its expression in various cancer cells and its impact on cancer progression. PD-1's functions extend beyond immune regulation, as it has been found to both promote and suppress tumor growth, depending on the cancer type. These findings have significant implications for the future of cancer treatment and our understanding of the immune response in the context of cancer. This article calls for further research into the multifaceted roles of PD-1 to optimize its therapeutic potential and improve patient outcomes in the fight against cancer.

IL-6-Driven Autocrine Lactate Promotes Immune Escape of Uveal Melanoma

Purpose

Early metastasis, in which immune escape plays a crucial role, is the leading cause of death in patients with uveal melanoma (UM); however, the molecular mechanism underlying UM immune escape remains unclear, which greatly limits the clinical application of immunotherapy for metastatic UM.

Methods

Transcriptome profiles were revealed by RNA-seq analysis. TALL-104 and NK-92MI-mediated cell killing assays were used to examine the immune resistance of UM cells. The glycolysis rate was measured by extracellular acidification analysis. Protein stability was evaluated by CHX-chase assay. Immunofluorescence histochemistry was performed to detect protein levels in clinical UM specimens.

Results

Continuous exposure to IL-6 induced the expression of both PD-L1 and HLA-E in UM cells, which promoted UM immune escape. Transcriptome analysis revealed that the expression of most metabolic enzymes in the glycolysis pathway, especially the rate-limiting enzymes, PFKP and PKM, was upregulated, whereas enzymes involved in the acetyl-CoA synthesis pathway were downregulated after exposure to IL-6. Blocking the glycolytic pathway and lactate production by knocking down PKM and LDHA decreased PD-L1 and HLA-E protein, but not mRNA, levels in UM cells treated with IL-6. Notably, lactate secreted by IL-6-treated UM cells was crucial in influencing PD-L1 and HLA-E stability via the GPR81-cAMP-PKA signaling pathway.

Conclusions

Our data reveal a novel mechanism by which UM cells acquire an immune-escape phenotype by metabolic reprogramming and reinforce the importance of the link between inflammation and immune escape.

From Molecular Biology to Novel Immunotherapies and Nanomedicine in Uveal Melanoma

Molecular biology studies of uveal melanoma have resulted in the development of novel immunotherapy approaches including tebentafusp-a T cell-redirecting bispecific fusion protein. More biomarkers are currently being studied. As a result, combined immunotherapy is being developed as well as immunotherapy with bifunctional checkpoint inhibitory T cell engagers and natural killer cells. Current trials cover tumor-infiltrating lymphocytes (TIL), vaccination with IKKb-matured dendritic cells, or autologous dendritic cells loaded with autologous tumor RNA. Another potential approach to treat UM could be based on T cell receptor engineering rather than antibody modification. Immune-mobilizing monoclonal T cell receptors (TCR) against cancer, called ImmTAC TM molecules, represent such an approach. Moreover, nanomedicine, especially miRNA approaches, are promising for future trials. Finally, theranostic radiopharmaceuticals enabling diagnosis and therapy with the same molecule bring hope to this research.

Identification and validation of an immune-relevant risk signature predicting survival outcome and immune infiltration in uveal melanoma

PURPOSE

The current study aimed to reveal a novel immune-related signature to evaluate immune infiltration status and the survival outcome for patients with uveal melanoma (UM).

METHODS

Based on 80 UM samples from the Cancer Genome Atlas, the transcriptome gene expression and clinical characteristics were analyzed to identify immune-related genes that contributed most to prognosis based on LASSO Cox regression. By combining the gene expression level with the corresponding regression coefficient, a risk score was calculated and all patients were divided into high- and low-risk groups. Survival, tumor-infiltrating immune cell abundance, dysregulated signaling pathways, immunophenoscore and tumor mutation burden were compared between two groups. Validation of the risk signature was performed in GSE22138 and GSE44295 cohort. For evaluating the immunotherapy efficacy, 348 advanced urothelial cancer patients treated with immune checkpoint inhibitor (ICI) were used for external validation.

RESULTS

Nine immune-related prognostic genes were identified under the LASSO Cox regression in the TCGA cohort; they are ACKR2, AREG, CCL5, CLEC11A, IGKV1-33, IL36B, NROB1, TRAV8-4 and TRBV28. Better prognosis, elevated immune cell infiltration, decreased immune-suppressive cell infiltration, immune response-related pathways and higher immunophenoscore were found in low-risk patients, with better ICI treatment response rate.

CONCLUSION

The identified immune risk signature was demonstrated to be associated with the favorable immune infiltration, prognosis and immunotherapeutic efficacy, which may provide clues for survival evaluation and immune treatment.

Genetic and Epigenetic Features of Uveal Melanoma-An Overview and Clinical Implications

Uveal melanoma (UM) is rare, but it is the most common primary intraocular malignancy among adults. This review represents the molecular, genetic, and immunobiological mechanisms involved in UM carcinogenesis and progression, as well as data about the association of chromosomal changes, genetic mutations, selective proteins, and biochemical biomarkers with the clinical implications of UM. Genetic analysis has the potential to identify patients with a high risk of UM metastasis, enabling management that is more effective and allowing for the follow-up of patients. Advancements in molecular characterization of UM offer opportunities to develop targeted therapeutic strategies by focusing on relevant signaling pathways. Changes in miRNA expression could be useful in the diagnosis and prognosis of UM, due to unique miRNA profiles in melanoma cells or tissue and its association with metastasis. Although liver function tests do not provide enough data on the prognosis of UM, due to the high frequency of liver metastasis, liver function tests (LFTs) might be useful indicators; however, the absence of rising LFT values cannot lead to the exclusion of liver metastases. Molecular analysis of tumor tissue will allow us to identify patients with the added benefit of new therapeutic agents and provide a better insight into melanoma pathogenesis and its biological behavior.

Nuclear PD-L1 promotes EGR1-mediated angiogenesis and accelerates tumorigenesis

Targeting programmed cell death protein ligand 1 (PD-L1) remains one of the most essential immunotherapies in cancer^1,2. PD-L1 has been detected in the nucleus in multiple malignancies, playing an oncogenic role independent of immune checkpoint regulation^3-5. Howbeit, the regulatory function of nuclear PD-L1 (nPD-L1) remains to be fully understood. Here, we report that nPD-L1 is an endogenous accelerator for cancer angiogenesis. First, we found that an abundant proportion of PD-L1 was distributed within the nucleus of uveal melanoma samples, which is associated with an unfavorable outcome. Moreover, the capacity of promoting angiogenesis was largely attenuated in the nPD-L1-deficient cells both in vivo and in vitro. Mechanistically, nPD-L1 facilitates p-STAT3 binding to the promoter of early growth response-1 (EGR1), resulting in the activation of EGR1-mediated angiogenesis. Therapeutically, the inhibition of histone deacetylase 2 restores the normal acetylation level of PD-L1, blocking its nuclear translocation and thereby attenuating tumor angiogenesis. Conclusively, we reveal that nPD-L1 promotes angiogenesis in malignancies, and provide a novel anti-vascularization strategy through blocking aberrant PD-L1 nuclear translocation for tumor therapy.

Immune-related toxicity and soluble profile in patients affected by solid tumors: a network approach

BACKGROUND

Immune checkpoint inhibitors (ICIs) have particular, immune-related adverse events (irAEs), as a consequence of interfering with self-tolerance mechanisms. The incidence of irAEs varies depending on ICI class, administered dose and treatment schedule. The aim of this study was to define a baseline (T0) immune profile (IP) predictive of irAE development.

METHODS

A prospective, multicenter study evaluating the immune profile (IP) of 79 patients with advanced cancer and treated with anti-programmed cell death protein 1 (anti-PD-1) drugs as a first- or second-line setting was performed. The results were then correlated with irAEs onset. The IP was studied by means of multiplex assay, evaluating circulating concentration of 12 cytokines, 5 chemokines, 13 soluble immune checkpoints and 3 adhesion molecules. Indoleamine 2, 3-dioxygenase (IDO) activity was measured through a modified liquid chromatography-tandem mass spectrometry using the high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) method. A connectivity heatmap was obtained by calculating Spearman correlation coefficients. Two different networks of connectivity were constructed, based on the toxicity profile.

RESULTS

Toxicity was predominantly of low/moderate grade. High-grade irAEs were relatively rare, while cumulative toxicity was high (35%). Positive and statistically significant correlations between the cumulative toxicity and IP10 and IL8, sLAG3, sPD-L2, sHVEM, sCD137, sCD27 and sICAM-1 serum concentration were found. Moreover, patients who experienced irAEs had a markedly different connectivity pattern, characterized by disruption of most of the paired connections between cytokines, chemokines and connections of sCD137, sCD27 and sCD28, while sPDL-2 pair-wise connectivity values seemed to be intensified. Network connectivity analysis identified a total of 187 statistically significant interactions in patients without toxicity and a total of 126 statistically significant interactions in patients with toxicity. Ninety-eight interactions were common to both networks, while 29 were specifically observed in patients who experienced toxicity.

CONCLUSIONS

A particular, common pattern of immune dysregulation was defined in patients developing irAEs. This immune serological profile, if confirmed in a larger patient population, could lead to the design of a personalized therapeutic strategy in order to prevent, monitor and treat irAEs at an early stage.

Diagnostic utility of immunohistochemistry in concordance with mRNA analysis of PRAME in the stratification of high-risk uveal melanoma patients

Existing clinical indicators for metastatic risk classification and patient treatment of uveal melanoma (UM) in the Asian population are limited. Preferentially expressed antigen in melanoma (PRAME) has gained attention in the prognosis of cancers and considered as a potential biomarker in many tumors including UM. Therefore, this study investigated the expression of PRAME and its association with loss of nuclear BAP1 (nBAP1) as well as its correlation with clinicopathological parameters and patient outcome. Immunohistochemical expression of PRAME and BAP1 proteins were assessed in 66 prospective cases of UM. mRNA expression level was measured by quantitative real-time PCR. Kaplan-Meier curves and Cox proportional hazard models were used to analyze the correlation of protein expression with clinicopathological parameters, metastasis-free survival and overall survival. Nuclear PRAME (nPRAME) expression and loss of nBAP1 were observed in 24 and 62% cases, respectively. PRAME mRNA expression level was found to be upregulated in 64% (7/11) of metastatic patients. mRNA and immunoexpression of nPRAME were statistically significant with many clinicopathological high-risk factors. On univariate and multivariate analyses, high mitotic activity, extraocular invasion and presence of nPRAME expression were statistically significant (p < 0.05). On Kaplan-Meier survival analysis, patients expressing PRAME had significantly reduced metastasis-free survival (MFS) and overall survival (OS). MFS and OS were also reduced in patients expressing PRAME along with loss of nBAP1. Our data show that nPRAME expression, in combination with loss of nBAP1, could be a useful predictive biomarker in the therapeutic management of UM patients at high risk.

Actualities in the Morphology and Immunohistochemistry of Cutaneous and Ocular Melanoma: What Lies Ahead? A Single-Centre Study

Melanoma is the most aggressive melanocytic tumor whose incidence is continuously increasing worldwide.

METHODS

We highlight the morphological, immunohistochemistry, and particularities of various melanoma types based on the cases diagnosed in our department from 2017 to 2021.

RESULTS

We present 100 melanoma cases and one capsular nevus case. The most common type was nodular melanoma. The immunohistochemistry markers used were SRY-box transcription factor 10 (SOX10), S100 protein, human melanoma black 45 (HMB45), and melanoma antigen recognized by T cells 1 (Melan-A). Uveal melanoma and conjunctival melanoma represent particular tumors with independent prognostic factors. Uveal melanoma requires assessment of macrophages, microvascularisation, and mitoses. Sentinel lymph node metastases are essential targets that provide staging tools. Conjunctival melanoma and capsular nevi are diagnostic pitfalls.

CONCLUSION

Melanoma can appear in various forms, and sometimes the diagnosis might be unclear. Today, immunohistochemistry remains the most important tool in confirming the diagnosis and prognosis for this type of neoplasia.

Clinicopathologic features and survival outcomes of ocular melanoma: a series of 31 cases from a tertiary university hospital

Background

We aimed to determine the effect of clinicopathologic features on overall survival among Caucasian ocular melanoma patients in the Central Anatolia region of Turkey.

Methods

This single-center study included conjunctival (n = 12) and uveal (n = 19) melanoma patients diagnosed between January 2008 and March 2020. Clinicopathologic features and outcomes were reviewed retrospectively. Five cases were tested for BRAF V600 mutations with real-time polymerase chain reaction, and one case was tested with next-generation sequencing. Survival was calculated using the Kaplan-Meier method.

Results

Thirty-one patients had a mean initial age of 58.32 years (median, 61 years; range 25 to 78 years). There were 13 male and 18 female patients. The median follow-up time was 43.5 months (range, 6 to 155 months) for conjunctival melanoma and 35 months (range, 8 to 151 months) for uveal melanoma. When this study ended, eight of the 12 conjunctival melanoma patients (66.7%) and nine of the 19 uveal melanoma patients (47.4%) had died. The presence of tumor-infiltrating lymphocytes was related to improved overall survival in conjunctival melanoma (p = .014), whereas the presence of ulceration (p = .030), lymphovascular invasion (p = .051), tumor in the left eye (p = .012), tumor thickness of > 2 mm (p = .012), and mitotic count of >1/mm² (p = .012) reduced the overall survival in conjunctival melanoma. Uveal melanoma tumors with the largest diameter of 9.1–15 mm led to the lowest overall survival among subgroups (p = .035). Involvement of the conjunctiva (p=.005) and lens (p = .003) diminished overall survival in uveal melanoma. BRAF V600 mutation was present in one case of conjunctival melanoma, GNAQ R183Q mutation was present in one case of uveal melanoma. Patients with uveal melanoma presented with an advanced pathological tumor stage compared to those with conjunctival melanoma (p = .019).

Conclusions

This study confirmed the presence of tumor-infiltrating lymphocytes as a favorable factor in conjunctival melanoma and conjunctival and lens involvement as unfavorable prognostic factors in uveal melanoma for overall survival, respectively.

Contribution of the STAT Family of Transcription Factors to the Expression of the Serotonin 2B (HTR2B) Receptor in Human Uveal Melanoma

Uveal melanoma (UM) remains the most common intraocular malignancy among diseases affecting the adult eye. The primary tumor disseminates to the liver in half of patients and leads to a 6 to 12-month survival rate, making UM a particularly aggressive type of cancer. Genomic analyses have led to the development of gene-expression profiles that can efficiently predict metastatic progression. Among these genes, that encoding the serotonin receptor 2B (HTR2B) represents the most discriminant from this molecular signature, its aberrant expression being the hallmark of UM metastatic progression. Recent evidence suggests that expression of HTR2B might be regulated through the Janus kinase/Signal Transducer and Activator of Transcription proteins (JAK/STAT) intracellular signalization pathway. However, little is actually known about the molecular mechanisms involved in the abnormally elevated expression of the HTR2B gene in metastatic UM and whether activated STAT proteins participates to this mechanism. In this study, we determined the pattern of STAT family members expressed in both primary tumors and UM cell-lines, and evaluated their contribution to HTR2B gene expression. Examination of the HTR2B promoter sequence revealed the presence of a STAT putative target site (5′-TTC (N)3 GAA3′) located 280 bp upstream of the mRNA start site that is completely identical to the high affinity binding site recognized by these TFs. Gene profiling on microarrays provided evidence that metastatic UM cell lines with high levels of HTR2B also express high levels of STAT proteins whereas low levels of these TFs are observed in non-metastatic UM cells with low levels of HTR2B, suggesting that STAT proteins contribute to HTR2B gene expression in UM cells. All UM cell lines tested were found to express their own pattern of STAT proteins in Western blot analyses. Furthermore, T142 and T143 UM cells responded to interleukins IL-4 and IL-6 by increasing the phosphorylation status of STAT1. Most of all, expression of HTR2B also considerably increased in response to both IL-4 and IL-6 therefore providing evidence that HTR2B gene expression is modulated by STAT proteins in UM cells. The binding of STAT proteins to the −280 HTR2B/STAT site was also demonstrated by electrophoretic mobility shift assay (EMSA) analyses and site-directed mutation of that STAT site also abolished both IL-4 and IL-6 responsiveness in in vitro transfection analyses. The results of this study therefore demonstrate that members from the STAT family of TFs positively contribute to the expression of HTR2B in uveal melanoma.

Identification of Immune Cell Infiltration Landscape and Their Prognostic Significance in Uveal Melanoma

Uveal melanoma (UVM) is the most common primary intraocular cancer in adults. Increasing evidence has demonstrated that immune cell infiltration (ICI) is crucial in predicting patient outcomes and therapeutic efficacy. Thus, describing the immune cell infiltrative landscape of UVM tumors may yield a novel prognostic marker and provide direction for immunotherapeutic selection. In this study, the gene expression data and clinical information of UVM patients were obtained from the cancer genome atlas (TCGA) and gene expression omnibus (GEO) databases. The ICI landscape of UVM was analyzed using the CIBERSORT and ESTIMATE algorithms. Two ICI phenotypes were defined, and the ICI scores were calculated by using principal component analysis algorithms. We found that a subtype with high ICI scores had poorer prognosis and increased expression levels of immune checkpoint-related genes. This study demonstrates that ICI scores are an independent prognostic biomarker and highlights their value in predicting immunotherapeutic outcomes.

(-)-4-O-(4-O-β-D-glucopyranosylcaffeoyl) quinic acid exerts anti-tumour effects against uveal melanoma through PI3K/AKT pathway

PURPOSE

Uveal melanoma is the most common primary intraocular tumour in adults. There is no standard adjuvant treatment to prevent metastasis and no effective therapy in the metastatic setting. (-)-4-O-(4-O-β-D-glucopyranosylcaffeoyl) quinic acid (QA) is a new compound isolated from the endophytic fungus Penicillium sp.FJ-1 of Avicennia marina, with potent activities to inhibit the PI3K. Our work further investigated effects of QA against uveal melanoma and explored its underlying mechanisms.

METHODS

MP65 cells were treated with QA at different concentrations. CCK-8 assay was used to detect effects of QA on cell viability. PI staining was used to detect cell cycle arrest. Tumour model was established by injecting MP65 cells into nude mice subcutaneously. Tumour-bearing mice were divided into three groups (5 mice per group). Mice were treated with QA (5 or 10 mg/kg) or saline by intraperitoneal injection five times per week. RT-qPCR and western blot were used to detect the expression of genes and proteins, respectively.

RESULTS

QA significantly inhibited the proliferation of uveal melanoma cells and induced the cell cycle arrest as well as autophagy. Moreover, QA treatment significantly slowed tumour growth of uveal melanoma, shown by decreased tumour volume and weight. Furthermore, QA treatment markedly decreased the protein expression of p-PI3K and p-AKT in tumour tissues.

CONCLUSIONS

Our data provided scientific rationale to develop QA as a promising anti-tumour agent against uveal melanoma.

Anti-tumour drugs of marine origin currently at various stages of clinical trials (review)

Oncological diseases for a long time have remained one of the most significant health problems of modern society, which causes great losses in its labour and vital potential. Contemporary oncology still faces unsolved issues as insufficient efficacy of treatment of progressing and metastatic cancer, chemoresistance, and side-effects of the traditional therapy which lead to disabilities among or death of a high number of patients. Development of new anti-tumour preparations with a broad range of pharmaceutical properties and low toxicity is becoming increasingly relevant every year. The objective of the study was to provide a review of the recent data about anti-tumour preparations of marine origin currently being at various phases of clinical trials in order to present the biological value of marine organisms – producers of cytotoxic compounds, and the perspectives of their use in modern biomedical technologies. Unlike the synthetic oncological preparations, natural compounds are safer, have broader range of cytotoxic activity, can inhibit the processes of tumour development and metastasis, and at the same time have effects on several etiopathogenic links of carcinogenesis. Currently, practical oncology uses 12 anti-tumour preparations of marine origin (Fludarabine, Cytarabine, Midostaurin, Nelarabine, Eribulin mesylate, Brentuximab vedotin, Trabectedin, Plitidepsin, Enfortumab vedotin, Polatuzumab vedotin, Belantamab mafodotin, Lurbinectedin), 27 substances are at different stages of clinical trials. Contemporary approaches to the treatment of oncological diseases are based on targeted methods such as immune and genetic therapies, antibody-drug conjugates, nanoparticles of biopolymers, and metals. All those methods employ bioactive compounds of marine origin. Numerous literature data from recent years indicate heightened attention to the marine pharmacology and the high potential of marine organisms for the biomedicinal and pharmaceutic industries.

Immune marker signature helps to predict survival in uveal melanoma

The detailed molecular function of tumor microenvironment (TEM) in uveal melanoma (UVM) remains unclear. This study generated the immune index and the stromal index scores by ESTIMATE algorithm based on RNA-sequencing data with 80 UVM patients. There was no correlation between the immune stromal index and clinical parameters. The differentially expressed genes related to the immune stromal index were calculated and were described by functional annotations and protein-protein interaction network diagrams. After univariate and multivariate Cox regression analyses, there were four genes (HLA-J, MMP12, HES6, and ADAMDEC1) with significant prognostic significance. The prognostic model was constructed using these four characteristic genes, and the KM curve and tROC curve were described to show that the model had a better ability to predict survival outcomes and prognosis. The verification results in GSE62075 showed that HLA-J and HES6 were expressed differently in the cancer group than in the non-cancer group. This study indicates that the risk signature based on the immune index can be used as an indicator to evaluate the prognosis of patients with UVM.

Research Progress of Cancer Stem Cells in Uveal Melanoma

Uveal melanoma is the most common malignant tumor in adult eyes, mostly in the choroid, but also in the iris and ciliary body. Distant metastasis is found in nearly half of the patients. Cancer stem cells are a kind of cells with the ability of self-renewal and multidirectional differentiation, which are related to tumor invasion and metastasis. Although the concept of cancer stem cells is relatively mature in other tumors, its existence and verification methods in uveal melanoma are still uncertain. A more in-depth understanding of cancer stem cells and their mechanism may reveal new strategies to treat uveal melanoma. This article reviews the concept of cancer stem cells and their research progress in uveal melanoma, including identification, probable markers, cancer stem cell targeted drug therapy and the controversies and prospects in this field.

Publication trends of research on uveal melanoma during 2000-2020: a 20-year bibliometric study

Uveal melanoma (UM) is the most prevalent primary intraocular malignancy in adults. Despite a high rate of success in controlling it as a local disease, it is prone to distant metastasis, and its mechanism of metastasis has not been elucidated. This study analyzes trends in UM research and compares contributions from different countries, regions, institutions and authors. We collected all publications related to UM published from 2000 to 2020 from the Web of Science database. GraphPad Prism 6 was used to collect publication data and analyze publication trends. VOSviewer was used for data visualization. A total of 1,710 publications were considered. The United States contributed the most publications [668] and citations (19,605 times) as of 2020 with the highest H-index value [67]. Keywords were classified into three clusters, namely, clinical study, tumor-related study and gene mutation-related study. Average appearing years (AAY) of keywords were calculated. BAP1 (AAY of 2016.3), SF3B1 (AAY of 2015.8) and GNA11 (AAY of 2015.5) were identified as major focuses of this field. We conclude that the United States, Germany, England and the Netherlands have been the most productive regions in terms of UM research over the past two decades. Gene mutations such as GNAQ, GNA11 and BAP1 mutations are identified as potential research focuses.