Gene network-based and ensemble modeling-based selection of tumor-associated antigens with a predicted low risk of tissue damage for targeted immunotherapy.

BACKGROUND: Tumor-associated antigens and their derived peptides constitute an opportunity to design off-the-shelf mainline or adjuvant anti-cancer immunotherapies for a broad array of patients. A performant and rational antigen selection pipeline would lay the foundation for immunotherapy trials with the potential to enhance treatment, tremendously benefiting patients suffering from rare, understudied cancers. METHODS: We present an experimentally validated, data-driven computational pipeline that selects and ranks antigens in a multipronged approach. In addition to minimizing the risk of immune-related adverse events by selecting antigens based on their expression profile in tumor biopsies and healthy tissues, we incorporated a network analysis-derived antigen indispensability index based on computational modeling results, and candidate immunogenicity predictions from a machine learning ensemble model relying on peptide physicochemical characteristics. RESULTS: In a model study of uveal melanoma, Human Leukocyte Antigen (HLA) docking simulations and experimental quantification of the peptide-major histocompatibility complex binding affinities confirmed that our approach discriminates between high-binding and low-binding affinity peptides with a performance similar to that of established methodologies. Blinded validation experiments with autologous T-cells yielded peptide stimulation-induced interferon-γ secretion and cytotoxic activity despite high interdonor variability. Dissecting the score contribution of the tested antigens revealed that peptides with the potential to induce cytotoxicity but unsuitable due to potential tissue damage or instability of expression were properly discarded by the computational pipeline. CONCLUSIONS: In this study, we demonstrate the feasibility of the de novo computational selection of antigens with the capacity to induce an anti-tumor immune response and a predicted low risk of tissue damage. On translation to the clinic, our pipeline supports fast turn-around validation, for example, for adoptive T-cell transfer preparations, in both generalized and personalized antigen-directed immunotherapy settings.

Threshold Optimization for Tumor Markers S100b and MIA in Uveal Melanoma - A Single Center Analysis.

BACKGROUND/AIM: Uveal melanoma (UM) is the most common malignant tumor of the eye in adults. Metastases develop in 50% of the patients, predominantly in the liver. In UM, the cut-off concentrations of the blood-based tumor markers S100b and MIA are inconclusive. PATIENTS AND METHODS: In this retrospective monocenter study, we statistically evaluated 1,878 S100b and 1,768 MIA measurements in 244 patients with UM from 2011-2020. Threshold optimization was performed using receiver operating characteristic (ROC) curves. RESULTS: A total of 171 patients with non-metastatic UM (nmUM) and 73 patients with metastatic UM (mUM) showed no differences in sex, age at diagnosis or the affected eye. In mUM, 80% of the patients developed metastases to the liver at a median of 46 months after initial diagnosis. The sensitivity and specificity of S100b was 16.10% and 94.52%, and that of MIA was 31.86% and 81.42%, respectively. ROC curves revealed poor values for the area under the curve of 0.57 for S100b and 0.55 for MIA. The optimal cut-off concentration to detect metastases was 0.14 µg/l for S100b and 17.4 ng/ml for MIA. With at least one tumor marker elevated, optimized sensitivity was 20.40% and specificity 96.76%. CONCLUSION: Current thresholds for S100b and MIA in UM are not able to detect early metastatic disease and require additional diagnostics to clarify false positive results. Threshold optimization considering both S100b and MIA results in a better diagnostic validity with an acceptable specificity and a poor sensitivity. Highly sensitive blood-based and imaging methods to detect metastases early in UM are urgently needed.

Liver-directed treatment is associated with improved survival and increased response to immune checkpoint blockade in metastatic uveal melanoma: results from a retrospective multicenter trial.

Metastases of uveal melanoma (UM) spread predominantly to the liver. Due to low response rates to systemic therapies, liver-directed therapies (LDT) are commonly used for tumor control. The impact of LDT on the response to systemic treatment is unknown. A total of 182 patients with metastatic UM treated with immune checkpoint blockade (ICB) were included in this analysis. Patients were recruited from prospective skin cancer centers and the German national skin cancer registry (ADOReg) of the German Dermatologic Cooperative Oncology Group (DeCOG). Two cohorts were compared: patients with LDT (cohort A, n = 78) versus those without LDT (cohort B, n = 104). Data were analyzed for response to treatment, progression-free survival (PFS), and overall survival (OS). The median OS was significantly longer in cohort A than in cohort B (20.1 vs. 13.8 months; P = 0.0016) and a trend towards improved PFS was observed for cohort A (3.0 vs. 2.5 months; P = 0.054). The objective response rate to any ICB (16.7% vs. 3.8%, P = 0.0073) and combined ICB (14.1% vs. 4.5%, P = 0.017) was more favorable in cohort A. Our data suggest that the combination of LDT with ICB may be associated with a survival benefit and higher treatment response to ICB in patients with metastatic UM.

Immune Checkpoint Blockade for Metastatic Uveal Melanoma: Re-Induction following Resistance or Toxicity.

Re-induction with immune checkpoint blockade (ICB) needs to be considered in many patients with uveal melanoma (UM) due to limited systemic treatment options. Here, we provide hitherto the first analysis of ICB re-induction in UM. A total of 177 patients with metastatic UM treated with ICB were included from German skin cancer centers and the German national skin cancer registry (ADOReg). To investigate the impact of ICB re-induction, two cohorts were compared: patients who received at least one ICB re-induction (cohort A, n = 52) versus those who received only one treatment line of ICB (cohort B, n = 125). In cohort A, a transient benefit of overall survival (OS) was observed at 6 and 12 months after the treatment start of ICB. There was no significant difference in OS between both groups (p = 0.1) with a median OS of 16.2 months (cohort A, 95% CI: 11.1-23.8) versus 9.4 months (cohort B, 95% CI: 6.1-14.9). Patients receiving re-induction of ICB (cohort A) had similar response rates compared to those receiving ICB once. Re-induction of ICB may yield a clinical benefit for a small subgroup of patients even after resistance or development of toxicities.

Clinical determinants of long-term survival in metastatic uveal melanoma.

This study aimed to identify prognostic factors in patients with metastatic uveal melanoma (UM) that were associated with long-term survival in a real-world setting. A total of 94 patients with metastatic UM were included from German skin cancer centers and the German national skin cancer registry (ADOReg). Data were analyzed for the response to treatment, progression-free survival, and overall survival (OS). Prognostic factors were explored with univariate Cox regression, log-rank, and χ2-tests. Identified factors were subsequently validated after the population was divided into two cohorts of short-term survival (< 2 years OS, cohort A, n = 50) and long-term survival (> 2 years OS, cohort B, n = 44). A poor ECOG performance status (hazard ratio [HR] 2.0, 95% confidence interval [CI] 1.0-3.9) and elevated serum LDH (HR 2.0, 95% CI 1.0-3.8) were associated with a poor OS, whereas a good response to immune checkpoint blockade (ICB, p < 0.001), radiation therapy (p < 0.001), or liver-directed treatments (p = 0.01) were associated with a prolonged OS. Long-term survivors (cohort B) showed a higher median number of organs affected by metastasis (p < 0.001), while patients with liver metastases only were more common in cohort A (40% vs. 9%; p = 0.002). A partial response to ICB was observed in 16% (12/73), being 21% (8/38) for combined ICB, 17% (1/6) for single CTLA4 inhibition, and 10% (3/29) for single PD1 inhibition. One complete response occurred in cohort B with combined ICB. We conclude that the response to ICB and the presence of extrahepatic disease were favorable prognostic factors for long-term survival.

Immune Checkpoint Blockade for Metastatic Uveal Melanoma: Patterns of Response and Survival According to the Presence of Hepatic and Extrahepatic Metastasis.

BACKGROUND: Since there is no standardized and effective treatment for advanced uveal melanoma (UM), the prognosis is dismal once metastases develop. Due to the availability of immune checkpoint blockade (ICB) in the real-world setting, the prognosis of metastatic UM has improved. However, it is unclear how the presence of hepatic and extrahepatic metastasis impacts the response and survival after ICB. METHODS: A total of 178 patients with metastatic UM treated with ICB were included in this analysis. Patients were recruited from German skin cancer centers and the German national skin cancer registry (ADOReg). To investigate the impact of hepatic metastasis, two cohorts were compared: patients with liver metastasis only (cohort A, n = 55) versus those with both liver and extra-hepatic metastasis (cohort B, n = 123). Data were analyzed in both cohorts for response to treatment, progression-free survival (PFS), and overall survival (OS). The survival and progression probabilities were calculated with the Kaplan-Meier method. Log-rank tests, χ2 tests, and t-tests were performed to detect significant differences between both cohorts. RESULTS: The median OS of the overall population was 16 months (95% CI 13.4-23.7) and the median PFS, 2.8 months (95% CI 2.5-3.0). The median OS was longer in cohort B than in cohort A (18.2 vs. 6.1 months; p = 0.071). The best objective response rate to dual ICB was 13.8% and to anti-PD-1 monotherapy 8.9% in the entire population. Patients with liver metastases only had a lower response to dual ICB, yet without significance (cohort A 8.7% vs. cohort B 16.7%; p = 0.45). Adverse events (AE) occurred in 41.6%. Severe AE were observed in 26.3% and evenly distributed between both cohorts. CONCLUSION: The survival of this large cohort of patients with advanced UM was more favorable than reported in previous benchmark studies. Patients with both hepatic and extrahepatic metastasis showed more favorable survival and higher response to dual ICB than those with hepatic metastasis only.

Intraocular tumor-associated lymphangiogenesis a novel prognostic factor for ciliary body melanomas with extraocular extension?

PURPOSE: To evaluate whether intraocular tumor-associated lymphangiogenesis contributes to prognosis of ciliary body melanomas with extraocular extension and to study its association with other tumor characteristics. DESIGN: Nonrandomized, retrospective case series. PARTICIPANTS: Twenty consecutive patients enucleated for a malignant melanoma of the ciliary body with extraocular extension. METHODS: Lymphatic vessels were identified using lymphatic vascular endothelial-specific hyaluronic acid receptor-1 (LYVE-1) and podoplanin as specific immunohistochemical markers for lymphatic vascular endothelium. Baseline tumor characteristics included intra- and extraocular tumor size, 2009 tumor, node, metastasis (TNM) classification, route of extraocular spread, tumor cell type, mitotic rate, Ki-67 proliferation-index, microvascular patterns and density, tumor-infiltrating lymphocytes and macrophages, and expression of human leukocyte antigen (HLA) class I and insulin-like growth factor-1 receptor. Kaplan-Meier and Cox regression analyses of melanoma-specific survival were performed. MAIN OUTCOME MEASURES: Prevalence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels and association with intraocular tumor characteristics and metastasis-free survival. RESULTS: Intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels could be detected in 12 (60%) of 20 ciliary body melanomas with extraocular extension. Presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels was significantly associated with larger intra- (P = 0.002) and extraocular tumor size (P<0.001), higher TNM categories (P = 0.004), epithelioid cellularity (P = 0.016), higher mitotic rate (P = 0.003), higher Ki-67 proliferation-index (P = 0.049), microvascular networks (P = 0.005), higher microvascular density (P = 0.003), more tumor-infiltrating macrophages (P = 0.002), higher expression of HLA class I (P = 0.046), and insulin-like growth factor-1 receptor (P = 0.033), but not significantly with route of extraocular spread (P = 0.803), and tumor-infiltrating lymphocytes (P = 0.069). Melanoma-specific mortality rates increased significantly with the presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels (P = 0.008). By multivariate Cox regression, tumor size (hazard ratio, 14.40; P = 0.002), and presence of intraocular lymphatic vessels (hazard ratio, 8.09; P = 0.04) were strong prognostic predictors of mortality. CONCLUSIONS: Intraocular peritumoral lymphangiogenesis seems to be associated with an increased mortality risk in patients with ciliary body melanomas and extraocular extension. This association may be primarily because of an association of intraocular lymphangiogenesis with greater tumor size and increased malignancy.

Intraocular lymphangiogenesis in malignant melanomas of the ciliary body with extraocular extension.

PURPOSE: To analyze whether lymphatic vessels can invade the normally alymphatic eye (lymphangiogenesis) in patients with malignant melanoma of the ciliary body with extraocular extension and to correlate these findings with metastasis-free survival. METHODS: Ten enucleated globes with the histopathologically and immunohistochemically (S-100, HMB-45, PNL-2, and Melan-A) confirmed diagnosis of malignant melanoma of the ciliary body with extraocular extension were matched with 10 globes with a ciliary body melanoma without extraocular extension regarding tumor size, cell type, melanin content, mitotic count, vascular networks, and patients' age. In all 20 cases, immunohistochemistry was performed to identify lymphatic vessels by using LYVE-1 and podoplanin as specific markers for lymphatic vascular endothelium. RESULTS: Intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels were detected in 7 of 10 malignant melanomas of the ciliary body with extraocular extension (two of these developed a regional lymph node metastasis). Lymphatic vessels were found only at the tumor periphery directly adjacent to the sclera within the eye, more often in tumors of the epithelioid type (P = 0.017, Mann-Whitney test). Ciliary body melanomas without extrascleral extension revealed no intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels. The presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels was significantly associated with lower metastasis-free survival rates (P = 0.038, log-rank test). CONCLUSIONS: Malignant melanomas of the ciliary body with extraocular extension show intraocular lymphatic vessels. This first evidence of lymphangiogenesis into the normally alymphatic eye may explain the increased risk of lymphatic metastasis in ciliary body melanoma with extraocular extension.

Acute syphilitic chorioretinitis after a missed primary diagnosis: a case report.

INTRODUCTION: Syphilis is well known as an infectious disease which can present with a large variety of symptoms. Clinical diagnosis can be difficult and may be complicated in modern medicine by immunosuppressive treatment and possible side effects of medication. CASE PRESENTATION: We describe a rare case of placoid chorioretinitis due to Treponema pallidum which developed after the primary symptom of proteinuria was not recognized as a rare manifestation of syphilis. Diagnosis of syphilitic chorioretinitis and/or endophthalmitis was made by broad range amplification of the bacterial 16S ribosomal RNA gene obtained from vitreous after diagnostic vitrectomy. CONCLUSION: This case shows that clinicians should be alert in patients with proteinuria and chorioretinitis as they can represent rare manifestations of syphilis. Syphilis should be in the differential diagnosis of any unknown symptom and in the presumed side effects of medication.