Publications by authors named "Joost A P Rens"

Unlabelled: Drugs that kill tumors through multiple mechanisms have the potential for broad clinical benefits. Here, we first developed an in silico multiomics approach (BipotentR) to find cancer cell-specific regulators that simultaneously modulate tumor immunity and another oncogenic pathway and then used it to identify 38 candidate immune-metabolic regulators. We show the tumor activities of these regulators stratify patients with melanoma by their response to anti-PD-1 using machine learning and deep neural approaches, which improve the predictive power of current biomarkers.

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Although melanoma progression and staging is clinically well characterized, a large variation is observed in pathogenesis, progression, and therapeutic responses. Clearly, intrinsic characteristics of melanoma cells contribute to this variety. An important factor, in both progression of the disease and response to therapy, is the tumor-associated vasculature.

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Aims: Malignant melanoma is the most aggressive form of skin cancer, and metastatic dissemination to regional and visceral sites is responsible for the majority of melanoma-related mortalities. In a recent study by our group, we observed reduced expression of tissue inhibitor of metalloproteinase-3 (TIMP3) in the majority of stage III melanoma samples studied. TIMP3 has been reported as a tumour suppressor in several human malignancies, with reduced expression correlating with poor clinical outcome.

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Therapy of melanoma using T-cells with genetically introduced T-cell receptors (TCRs) directed against a tumor-selective cancer testis antigen (CTA) NY-ESO1 demonstrated clear antitumor responses in patients without side effects. Here, we exploited the concept of TCR-mediated targeting through introduction of single-chain variable fragment (scFv) antibodies that mimic TCRs in binding major histocompatibility complex-restricted CTA. We produced scFv antibodies directed against Melanoma AntiGEn A1 (MAGE A1) presented by human leukocyte antigen A1 (HLA-A1), in short M1/A1, and coupled these TCR-like antibodies to liposomes to achieve specific melanoma targeting.

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Background And Purpose: We demonstrated previously that the administration of tumor necrosis factor alpha (TNF-α) for the treatment of solid tumors enhanced the response to chemotherapy by augmenting intratumoral drug accumulation. TNF-α changes the integrity of the endothelial cell monolayer in combination with interferon gamma (IFN-γ), which is further enhanced by the addition of peripheral blood mononuclear cells (PBMCs). The improved effect of PBMCs was mostly induced by the endogenous production of interleukin-1beta (IL-1ß) after TNF-α stimulation.

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The angiogenic potential of solid tumors, or the ability to initiate neovasculature development from pre-existing host vessels, is facilitated by soluble factors secreted by tumor cells and involves breaching of extracellular matrix barriers, endothelial cell (EC) proliferation, migration and reassembly. We evaluated the angiogenic potential of human melanoma cell lines differing in their degree of aggressiveness, based on their ability to regulate directionally persistent EC migration. We observed that conditioned-medium (CM) of the aggressive melanoma cell line BLM induced a high effective migratory response in ECs, while CMs of Mel57 and 1F6 had an inhibitory effect.

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Inactivation of the tumor suppressor E-cadherin is an important event during breast tumorigenesis, as its decreased expression is linked to aggressiveness and metastasis. However, the relationship between the different modes of E-cadherin inactivation (mutation versus promotor hypermethylation) and breast cancer cell behavior is incompletely understood. The high correlation between E-cadherin inactivation status and cell morphology in vitro suggests different biological roles for the two inactivation modes during breast tumorigenesis.

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Objective: In cardiovascular regulation, heme oxygenase-1 (HO-1) activity has been shown to inhibit vascular smooth muscle cell (VSMC) proliferation by promoting cell cycle arrest at the G1/S phase. However, the effect of HO-1 on VSMC migration remains unclear. We aim to elucidate the mechanism by which HO-1 regulates PDGFBB-induced VSMC migration.

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Endothelial monocyte-activating polypeptide-II (EMAP-II), a proinflammatory cytokine with antiangiogenic properties, renders tumours sensitive to tumour necrosis factor-alpha (TNF) treatment. The exact mechanisms for this effect remain unclear. Here we show that human endothelial cells (EC) are insensitive to TNF-induced apoptosis but after a short pre-treatment with EMAP-II, EC quickly undergo TNF-induced apoptosis.

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Cell migration is crucial in virtually every biological process and strongly depends on the nature of the surrounding matrix. An assay that enables real-time studies on the effects of defined matrix components and growth factors on cell migration is not available. We have set up a novel, quantitative migration assay, which enables unharmed cells to migrate along a defined matrix.

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Tumour necrosis factor-alpha (TNF) has been used in the clinic for more than 10 years in an isolated limb perfusion (ILP). However, intra-tumoural expression of TNF receptor-1 (TNF-R1) and TNF-R1 upregulating factors are unknown. We determined the expression of TNF-R1, proEMAP and endothelial monocyte-activating polypeptide-II (EMAP-II) before and after ILP and evaluated this against clinical response.

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