A deeper understanding of the parameters driving response and resistance to immunotherapy is needed to improve the low response rates observed in breast cancer patients. Research into immunotherapy... Show moreA deeper understanding of the parameters driving response and resistance to immunotherapy is needed to improve the low response rates observed in breast cancer patients. Research into immunotherapy response has predominantly focused on T cells, however effective immune responses require tightly regulated crosstalk between innate and adaptive immune cells. By combining profiling of blood and tumors from metastatic breast cancer patients with mechanistic studies in mouse models, we uncovered the critical role of eosinophils in immunotherapy response, and we provide proof-of-principle for eosinophil engagement to enhance immunotherapy efficacy. Focusing on resistance mechanisms to immunotherapy, we demonstrate that neoadjuvant immunotherapy triggers persistent and systemic regulatory T cell activation which blunts therapeutic efficacy against metastatic spread of breast tumors. In addition, we demonstrate that neutrophils in the tumor microenvironment pose a barrier to immunotherapy response through T cell suppression. Lastly, we demonstrate that combining the immunomodulatory agent PD1-IL2v with cisplatin is a powerful approach to induce a broad activation of systemic and intratumoral adaptive and innate immunity, resulting in effective immunotherapy responses. Overall, this work identifies several key players and their interconnectivities in anti-tumor immunity and tumor-induced immunosuppression that may be therapeutically exploited to improve immunotherapy responses for breast cancer patients. Show less
This thesis represents a comprehensive investigation into the control of cancer stemness and metastatic initiation using a combination of advanced zebrafish xenograft models and in vitro assays.... Show moreThis thesis represents a comprehensive investigation into the control of cancer stemness and metastatic initiation using a combination of advanced zebrafish xenograft models and in vitro assays. The discoveries made and the evaluation of drug efficacy provide valuable insights for the development of novel therapeutic approaches in the fight against metastatic cancer. Show less
Prostate cancer (PCa) is one of the most prevalent cancer in males. Although the majority of the patients can benefit from the present clinical treatments, 20%-30% of the patients who originally... Show moreProstate cancer (PCa) is one of the most prevalent cancer in males. Although the majority of the patients can benefit from the present clinical treatments, 20%-30% of the patients who originally respond to the therapy still develop incurable, castration-resistance bone metastases, which is a main cause of death in PCa . In this thesis, I combined an advanced zebrafish xenograft model with in vitro cellular approaches and mice xenografts to study the early stage of PCa metastasis. Using this comprehensive esearch platform, I identified multiple key signaling pathways that play essential roles in promoting the onset of PCa metastatis. The pathways I discovered include Cripto-associated EMT plasticity, CDC-42-N-Wasp-Cortactin associated mechanosensing and mechanotransduction, microenvironment dependent NF-ĸB-Activin A signaling pathway, and AMPK-Autophagy dependent metabolic stress coping pathway. Show less
In het proefschrift van Martine van Miltenburg wordt het onderzoek naar de rol van FAK en annexine A1 in borstkankerontwikkeling en uitzaaiing (metastasering) beschreven. E__n van de... Show moreIn het proefschrift van Martine van Miltenburg wordt het onderzoek naar de rol van FAK en annexine A1 in borstkankerontwikkeling en uitzaaiing (metastasering) beschreven. E__n van de sleutelprocessen bij de metastasering is de verandering van het rustige fenotype van kankercellen naar het beweeglijke fenotype. Een belangrijke ontdekking is dat het eiwit annexine A1 een belangrijke rol speelt in metastasering van basale borstkanker. Verhoogde expressie van annexine A1 draagt bij aan beweeglijkheid en daarmee agressief gedrag van tumorcellen. Hoe hoger de expressie van annexine A1, hoe meer uitzaaiingen, simpel gezegd. Wanneer annexine A1 wordt uitgeschakeld in deze cellen verandert de cel van het agressieve gedrag naar een ___rustige___ tumorcel, en ontstaan er beduidend minder uitzaaiingen. Ondanks de veelbelovende resultaten is het geen optie om remming van annexine A1 als anti-kanker therapie te gebruiken omdat annexine A1 ook in gezonde lichaamscellen een belangrijke functie heeft. Maar de onderzoekers denken wel dat annexine A1 een ___marker___ voor basale borstkanker kan worden. Doordat annexine A1 specifiek in basale borstkanker verhoogd tot expressie komt zou het als marker wellicht goed gebruikt kunnen worden om dit relatief agressieve type borstkanker type te bepalen bij pati__nten. Show less
Cutaneous and uveal melanoma are malignant tumours with no treatment available once the metastases occur. Despite both melanomas are highly immunogenic, and often despite the presence of potent... Show moreCutaneous and uveal melanoma are malignant tumours with no treatment available once the metastases occur. Despite both melanomas are highly immunogenic, and often despite the presence of potent anti-tumour immune cells in patients__ blood, in more than 95% of patients, tumour growth remains unaffected. Hereby we investigate the mechanisms that help melanomas to escape from the spontaneous or activated by vaccination cytotoxicity of T lymphocytes and discuss the impact of local microenvironment created by melanoma, focusing on the role of immunomodulatory dendritic cells. Show less
