Cancer immunotherapies utilizing immune checkpoint blockade (ICB) therapy targeting CTLA-4 and PD-1/PD-L1 relieve tumor-induced immune suppression and induce durable tumor regression. The use of... Show moreCancer immunotherapies utilizing immune checkpoint blockade (ICB) therapy targeting CTLA-4 and PD-1/PD-L1 relieve tumor-induced immune suppression and induce durable tumor regression. The use of ICB therapy have demonstrated remarkable therapeutic efficacy in a proportion of patients with melanoma. However, still a substantial percentage of patients does not respond (durable) to ICB treatment and many questions remain. Therefore, in this thesis, the aim is to improve our understanding of ICB efficacy. We demonstrate the promise of neoadjuvant ICB therapy (approach in which ICB therapy is applied before surgery) and analyze different cohorts of melanoma patients. This results in the identification of several markers that are associated with prognosis, including IFN-y related gene signature score, Batf3 dendritic cell associated gene signature score, tumor mutational burden and systemic LRG1 expression. These markers can potentially be targeted and might facilitate rational combination therapies that can boost the efficacy of ICB therapy. For this purpose, we perform a repurposing compound screen that targets antigen cross-presentation. Togethers, this work increases our understanding of factors that determine ICB therapy efficacy and toxicity, with the goal to identify novel strategies to improve outcome of melanoma patients in a rationale and personal manner. Show less
Background: The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune... Show moreBackground: The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune responses. Furthermore, in trials using fecal microbiota transplantation (FMT) to treat melanoma patients unresponsive to immune checkpoint inhibitors (ICI), complete responses (CR), partial responses (PR), and durable stable disease (SD) have been observed. However, the underlying mechanism determining which patients will or will not respond and what the optimal FMT composition is, has not been fully elucidated, and a discrepancy in microbial taxa associated with clinical response has been observed between studies. Furthermore, it is unknown whether a change in the microbiome itself, irrespective of its origin, or FMT from ICI responding donors, is required for reversion of ICI-unresponsiveness. To address this, we will transfer microbiota of either ICI responder or nonresponder metastatic melanoma patients via FMT. Methods: In this randomized, double-blinded phase Ib/IIa trial, 24 anti-PD1-refractory patients with advanced stage cutaneous melanoma will receive an FMT from either an ICI responding or nonresponding donor, while continuing anti-PD-1 treatment. Donors will be selected from patients with metastatic melanoma treated with anti-PD-1 therapy. Two patients with a good response (& GE; 30% decrease according to RECIST 1.1 within the past 24 months) and two patients with progression (& GE; 20% increase according to RECIST 1.1 within the past 3 months) will be selected as ICI responding or nonresponding donors, respectively. The primary endpoint is clinical benefit (SD, PR or CR) at 12 weeks, confirmed on a CT scan at 16 weeks. The secondary endpoint is safety, defined as the occurrence of grade & GE; 3 toxicity. Exploratory endpoints are progression-free survival and changes in the gut microbiome, metabolome, and immune cells. Discussion: Transplanting fecal microbiota to restore the patients' perturbed microbiome has proven successful in several indications. However, less is known about the potential role of FMT to improve antitumor immune response. In this trial, we aim to investigate whether administration of FMT can reverse resistance to anti-PD-1 treatment in patients with advanced stage melanoma, and whether the ICI-responsiveness of the feces donor is associated with its effectiveness. Show less
Single-agent Talimogene Laherparepvec (T-VEC) was developed for treatment of unresectable and injectable stage III-IV melanoma. Since its approval and reimbursement, studies have reported varying... Show moreSingle-agent Talimogene Laherparepvec (T-VEC) was developed for treatment of unresectable and injectable stage III-IV melanoma. Since its approval and reimbursement, studies have reported varying response rates. The purpose of this systematic review and meta-analysis was to investigate the efficacy and safety of T-VEC. Of 341 publications that were identified, eight studies with a total of 642 patients were included. In patients with stage IIIB-IVM1a, the pooled complete-and overall response rate (CRR and ORR) were 41% and 64%, respectively. In patients with stage IIIB-IVM1c, the pooled CRR and ORR were 30% and 44%, respectively. In patients with stage IVM1b and IVM1c, the pooled CRR and ORR were 4% and 9%, respectively. Adverse events (AEs) were seen in 41-100% of all patients and 0-11% of AEs were severe. In conclusion, single agent T-VEC achieves the highest response rates in patients with early metastatic melanoma and is well-tolerated with generally only mild toxicities. Show less
Death in all types of melanomas is generally caused by metastasis. Uveal melanoma (UM) is the most common intraocular melanoma, there are currently no (patient-derived) animal models that... Show moreDeath in all types of melanomas is generally caused by metastasis. Uveal melanoma (UM) is the most common intraocular melanoma, there are currently no (patient-derived) animal models that faithfully recapitulate metastatic dissemination of UM. Here we generate embryonic zebrafish models for both the primary and disseminated stage of ocular melanoma. In doing so we can recapitulate the etiology of cancer in its totality. Subsequently, we developed a patient-derived zebrafish xenograft (zf-PDX) model, using spheroid cultures generated from metastatic and primary UM tissues. Harnessing this versatile model, we reveal high sensitivity of circulating UM cells to ferroptosis induction in vivo by Erastin and RSL3, implicating ferroptosis as a new potential therapy in metastatic UM.Increased melanin levels in cutaneous melanoma are associated with decreased patient survival. Melanin levels in primary uveal melanoma patient cells positively correlate with their metastatic potential in zebrafish. Modulation of melanin levels of pan-melanoma cells results in enhanced/reduced metastatic potential upon increased or decreased melanin levels, respectively. Melanin depletion sensitizes melanoma cells to ferroptosis inducers in zebrafish leading to a decreased metastatic burden. Collectively, our data identify melanin biosynthetic enzymes as potential future target to treat melanoma and show that melanin protects metastasizing melanoma cells from ferroptosis. Show less
Background: Recent reports suggest the limited efficacy of immune checkpoints inhibitors in advanced acral melanoma (AM). This study aims to investigate the clinical outcomes of immune checkpoint... Show moreBackground: Recent reports suggest the limited efficacy of immune checkpoints inhibitors in advanced acral melanoma (AM). This study aims to investigate the clinical outcomes of immune checkpoint inhibitors in patients with stage III and IV AM and compare them to cutaneous melanoma (CM). Methods: We included patients with advanced AM and CM treated with first-line anti -programmed cell death (PD)-1 monotherapy or ipilimumab-nivolumab registered in the prospective nationwide Dutch Melanoma Treatment Registry. Objective response rates, progression free survival (PFS) and overall survival (OS) were calculated. A Cox proportional hazard model was used to assess the prognostic factors with PFS and OS. Results: In total, 2058 patients (88 AM and 1970 CM) with advanced melanoma were included. First-line objective response rates were 34% for AM versus 54% for CM in the advanced anti-PD-1 cohort and 33% for AM versus 53% for CM in the advanced ipilimumab-nivolumab cohort. The Median PFS was significantly shorter for anti-PD-1 treated AM patients (3.1 months; 95%CI: 2.8-5.6) than patients with CM (10.1 months; 95%CI: 8.5-12.2) (P < 0.001). In patients with advanced melanoma, AM was significantly associated with a higher risk of progression (HRadj 1.63; 95%CI: 1.26-2.11 ; P < 0.001) and death (HRadj 1.54; 95%CI: 1.15-2.06; P Z 0.004) than CM. Conclusions: This study shows lower effectiveness of anti-PD-1 monotherapy and ipilimumab-nivolumab in AM, with lower response rates, PFS and OS than CM. This group of patients should be prioritised in the development of alternative treatment strategies. 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Show less
Ocular melanoma is a rare disease that originates from melanocytes in the eye. It is the most prevalent primary ocular malignancy in adults, and has a high metastatic rate. Two important questions... Show moreOcular melanoma is a rare disease that originates from melanocytes in the eye. It is the most prevalent primary ocular malignancy in adults, and has a high metastatic rate. Two important questions for good patient care are: 1) How to differentiate between (benign) nevi, and (malignant) melanoma?, and 2) How to treat this tumor best, particularly in cases with metastases?This thesis addresses two types of ocular melanoma: melanoma of the internal parts of the eye (uveal melanoma) and melanoma of the mucous membrane covering the eye (conjunctival melanoma). This thesis combines patient-related projects with projects from the lab.With new imaging techniques we demonstrate that oxygen values differ in eyes with melanoma compared to other eyes including those with a nevus. We use OCT-angiography to depict tumour vessels non-invasively in conjunctival and iris lesions. These two techniques may be used in the future to differentiate lesions, and to monitor patients after treatment.With studies in the lab we show that new drugs (immunotherapy) that are recently used in cutaneous melanoma, can also be used to treat conjunctival melanoma. We show that vascular growth in uveal melanoma is related to other (genetic and immunologic) characteristics, providing new clues for therapy. Show less
Although clinical aspects of melanoma have been extensively studied, the literature largely concerns relatively healthy 20-70 years old patients. Special populations, such as the elderly, children,... Show moreAlthough clinical aspects of melanoma have been extensively studied, the literature largely concerns relatively healthy 20-70 years old patients. Special populations, such as the elderly, children, patients with multiple primary melanoma and those with familial melanoma, are frequently excluded from clinical studies. The studies presented in this thesis were aimed to assess prognostic factors and management of patients with clinically localized melanoma, in particular among the aforementioned special populations. Show less
Melanoma is the most aggressive and lethal type of skin cancer since it has the ability to spread to other organs in the body making it harder to control the disease.In this thesis, we aim to... Show moreMelanoma is the most aggressive and lethal type of skin cancer since it has the ability to spread to other organs in the body making it harder to control the disease.In this thesis, we aim to explore the degree to which epigenetics play a role in melanoma, namely, inherited and acquired epigenetic alterations in melanoma susceptibility and development. Show less
Background: Checkpoint inhibitors have changed overall survival for patients with advanced melanoma. However, there is a lack of data on health-related quality of life (HRQoL) of long-term advanced... Show moreBackground: Checkpoint inhibitors have changed overall survival for patients with advanced melanoma. However, there is a lack of data on health-related quality of life (HRQoL) of long-term advanced melanoma survivors, years after treatment. Therefore, we evaluated HRQoL in long-term advanced melanoma survivors and compared the study outcomes with matched controls without cancer.Material and methods: Ipilimumab-treated advanced melanoma survivors without evidence of disease and without subsequent systemic therapy for a minimum of two years following last administration of ipilimumab were eligible for this study. The European Organization for Research and Treatment of Cancer quality of life questionnaire Core 30 (EORTC QLQ-C30), the Multidimensional Fatigue Inventory (MFI), the Hospital Anxiety and Depression Scale (HADS), and the Functional Assessment of Cancer Therapy-Melanoma questionnaire (FACT-M) were administered. Controls were individually matched for age, gender, and educational status. Outcomes of survivors and controls were compared using generalized estimating equations, and differences were interpreted as clinically relevant according to published guidelines.Results: A total of 89 survivors and 265 controls were analyzed in this study. After a median follow-up of 39 (range, 17-121) months, survivors scored significantly lower on physical (83.7vs. 89.8, difference (diff) = -5.80,p=.005), role (83.5vs.90, diff = -5.97,p=.02), cognitive (83.7vs.91.9, diff = -8.05,p=.001), and social functioning (86.5vs.95.1, diff = -8.49,p= <.001) and had a higher symptom burden of fatigue (23.0vs.15.5, diff = 7.48,p=.004), dyspnea (13.3vs.6.7, diff = 6.47p=.02), diarrhea (7.9vs.4.0, diff = 3.78,p=.04), and financial impact (10.5vs.2.5, diff = 8.07,p=.001) than matched controls. Group differences were indicated as clinically relevant.Discussion: Compared to matched controls, long-term advanced melanoma survivors had overall worse functioning scores, more physical symptoms, and financial difficulties. These data may contribute to the development of appropriate survivorship care. Show less
In summary, this thesis focused on the understanding the underlying mechanisms driving TNBC metastatic progression. We established DUB activity profiling methods and identified UCHL1 as a candidate... Show moreIn summary, this thesis focused on the understanding the underlying mechanisms driving TNBC metastatic progression. We established DUB activity profiling methods and identified UCHL1 as a candidate oncoprotein that promotes TGFβ-induced breast cancer metastasis. Importantly, we found UCHL1 activity inhibitor as a potential drug for TNBC therapy and developed UCHL1 activity-based probe. For vemurafenib-resistance melanoma, we provided insights that targeting TGFβ signaling may help to overcome drug resistant phenotype. Show less
Epidemiologic studies have reported inconsistent results regarding an association between Parkinson disease (PD) and cutaneous melanoma (melanoma). Identifying shared genetic architecture between... Show moreEpidemiologic studies have reported inconsistent results regarding an association between Parkinson disease (PD) and cutaneous melanoma (melanoma). Identifying shared genetic architecture between these diseases can support epidemiologic findings and identify common risk genes and biological pathways. Here, we apply polygenic, linkage disequilibrium-informed methods to the largest available case-control, genome-wide association study summary statistic data for melanoma and PD. We identify positive and significant genetic correlation (correlation: 0.17, 95% CI 0.10-0.24; P = 4.09 x 10(-06)) between melanoma and PD. We further demonstrate melanoma and PD-inferred gene expression to overlap across tissues (correlation: 0.14, 95% CI 0.06 to 0.22; P = 7.87 x 10(-04)) and highlight seven genes including PIEZO1, TRAPPC2L, and SOX6 as potential mediators of the genetic correlation between melanoma and PD. These findings demonstrate specific, shared genetic architecture between PD and melanoma that manifests at the level of gene expression. Show less
The aim of the research described in this thesis was to gain a better understanding of the role of the different immune cells and the different FcR on their cell surface, in antibody therapy and... Show moreThe aim of the research described in this thesis was to gain a better understanding of the role of the different immune cells and the different FcR on their cell surface, in antibody therapy and to investigate whether the effectiveness of the tumor-killing mechanisms, activated by the antibodies, can be improved. First, we investigated the role of FcR in various immune responses using a genetically modified mouse, in which all FcR were missing. After defining that role, we studied antibody therapy in a mouse model for melanoma in two different ways: on the one hand, after vaccination using a viral vector that expressed a melanoma antigen, on the other hand, by injecting a melanoma-specific antibody in combination with other substances that activate the immune system. Show less
Christodoulou, E.; Visser, M.; Potjer, T.P.; Stoep, N. van der; Rodriguez-Girondo, M.; Doorn, R. van; Gruis, N. 2019
Carriers of pathogenic variants in CDKN2A have a 70% life-time risk of developing melanoma and 15-20% risk of developing pancreatic cancer (PC). In the Netherlands, a 19-bp deletion in exon 2 of... Show moreCarriers of pathogenic variants in CDKN2A have a 70% life-time risk of developing melanoma and 15-20% risk of developing pancreatic cancer (PC). In the Netherlands, a 19-bp deletion in exon 2 of CDKN2A (p16-Leiden mutation) accounts for most hereditary melanoma cases. Clinical experience suggests variability in occurrence of melanoma and PC in p16-Leiden families. Thereby, the risk of developing cancer could be modified by both environmental and genetic contributors, suggesting that identification of genetic modifiers could improve patients' surveillance. In a recent genome-wide association study (GWAS), rs36115365-C was found to significantly modify risk of PC and melanoma in the European population. This SNP is located on chr5p15.33 and has allele-specific regulatory activities on TERT expression. Herein, we investigated the modifying capacities of rs36115365-C on PC and melanoma in a cohort of 283 p16-Leiden carriers including 29 diagnosed with PC, 171 diagnosed with melanoma, 21 diagnosed with both PC and melanoma and 62 with neither PC nor melanoma. In contrast to previously reported findings, we did not find a significant association of PC risk with risk variant presence as determined by Generalized Estimating Equations (GEE) modelling. Interestingly, carrier-ship of the risk variant had a significant protective effect for melanoma (OR - 0.703 [95% CI - 1.201 to - 0.205], p = 0.006); however, the observed association was no longer significant after exclusion of probands to assess possible influence of ascertainment. Collectively, genetic modifiers for the prediction of PC and melanoma risk in p16-Leiden carriers remain to be determined. Show less
Meijer, T.S.; Burgmans, M.C.; Fiocco, M.; Geus-Oei, L.F. de; Kapiteijn, E.; Leede, E.M. de; ... ; Vahrmeijer, A.L. 2019
Malignant melanoma is an aggressive cancer associated with a poor prognosis in patients with metastatic disease. As in many other cancers, the incidence of melanoma rises with age; and combined... Show moreMalignant melanoma is an aggressive cancer associated with a poor prognosis in patients with metastatic disease. As in many other cancers, the incidence of melanoma rises with age; and combined with the longer life expectancy, this led to an increasing prevalence of melanoma in the older population. Recently, immune checkpoint inhibitors significantly improved the treatment of melanoma given their efficacy and tolerability profile. Two major classes of agents include the anti-cytotoxic T lymphocyte-associated protein 4 (CFLA-4) inhibitors, such as ipilimumab, and the anti-programmed death-ligand 1 (PD-1) inhibitors, such as nivolumab and pembrolizumab. Treatment of metastatic disease with immune checkpoint inhibitors demonstrated improved efficacy and better safety profiles compared to cytotoxic drugs and appears to be an attractive treatment option. Nevertheless, there is a need for tools designed to better predict which older patients will benefit from its use and who will experience toxicities related to the treatment. Current data do not show a major increase in toxicity rates in older patients. However, patients above 75 are often under-represented and those who are included are not representative of the general population of older patients, thereby also stressing the need for real-life data. Ongoing research is aiming at maximizing the potential treatment efficacy and developing novel immune-targeting modalities. Future studies should include older patients and assess geriatric domains in these older patients to better guide decision-making. This review discusses published clinical trials and where known, the efficacy and toxicity in older patients. Moreover, the clinical implications and future perspectives are discussed, with current recommendations for older patients, management of toxicities, and a proposal for an initial approach to the treatment of older patients with metastatic melanoma. (C) 2018 Elsevier Ltd. All rights reserved. Show less
Teulings, H.E.; Tjin, E.P.M.; Willemsen, K.J.; Kleij, S. van der; Meulen, S. ter; Kemp, E.H.; ... ; Luiten, R.M. 2018
The focus of this thesis is uveal melanoma (UM) which, once metastasized, is lethal due to lack of effective treatment options. To repress p53 activity approximately 65% of UM tumors express high... Show moreThe focus of this thesis is uveal melanoma (UM) which, once metastasized, is lethal due to lack of effective treatment options. To repress p53 activity approximately 65% of UM tumors express high levels of the p53 inhibitory proteins MDMX or MDM2. The aim of this thesis is to unravel the oncogenic function of MDMX and provide new treatment options for patients with metastasized UM. Chapter 2 describes the regulation of the transcriptome by MDMX in UM and proposes novel p53-independent effects of MDMX, i.e. FOXO inhibition. In chapter 3 the opportunities of a combined targeting of two common signaling pathways as therapeutic intervention for metastasized UM patients is investigated. Genetic interference with either MDMX or PKC δ expression or activity showed that beneficial effects can already be achieved by a more specific targeting, which is presumable less toxic to the patient. In chapter 4 it is described, opposed to what has been reported before, that enhancer of zeste homolog 2 (EZH2) inhibition poses a valuable novel therapeutic invention for UM. In chapter 5 it is shown that combining two clinically approved drugs, Quisinostat and Flavopiridol, could serve as an effective therapeutic intervention for UM patients. Show less
This thesis focused on different aspects of melanoma treatment with immunotherapy and targeted therapy. In chapter 2 we search for biomarkers that could be associated with overall survival in... Show moreThis thesis focused on different aspects of melanoma treatment with immunotherapy and targeted therapy. In chapter 2 we search for biomarkers that could be associated with overall survival in patients treated with ipilimumab. In chapter 3 we describe diarrea, a commonly seen side effect of immunotherapy. Here we show that there is no significant correlation between grade of diarrhea and severity of colitis as seen during endoscopy. Chapters 4 and 5 describe patients with brain metastases and/or leptomeningeal metastases. In chapter 4 we show the difference in overall survival in patients treated with vemurafenib, dabrafenib or the combination of dabrafenib + trametinib. Chapter 5 focusses on the treatment of leptomeningeal metastases. Here a significant difference in overall survival was noted between treated and untreated patients. Furthermore LDH was a predictive biomarker for overall survival. In chapter 6 we show that treating patients with vemurafenib beyond progression of disease has a significant impact on overall survival. Lastly in chapter 7 we review the past, present and future of treating patients with different kinds of cancer with tumor-infiltrating lymphocytes. Show less
