One of the major limitations in culturing complex tissues or organs is the lack of vascularization in the cultured tissue. Development of a functional capillary bed could overcome this problem.... Show moreOne of the major limitations in culturing complex tissues or organs is the lack of vascularization in the cultured tissue. Development of a functional capillary bed could overcome this problem. The zebrafish is a promising model for in vitro vasculogenesis and angiogenesis studies, as a replacement for currently used mammalian models. However, the culture of endothelial cells from this species is not well characterized. Here, we test different culture strategies, medium supplementations and culture substrates for their effect on the generation of putative endothelial (fli:GFP+ and kdrl:GFP+) cells and vascular morphogenesis in zebrafish blastocyst cell derived embryoid body culture. we have also developed a perfused culture model, using microfluidic technology, to culture zebrafish vascular networks. This study is a step forward to the development of zebrafish vascular networks in vitro. Show less
This thesis describes the role of 14q32 microRNAs in vascular remodelling. The 14q32 microRNA cluster contains 54 microRNAs in humans and is highly conserved in mammals. In part I of this thesis,... Show moreThis thesis describes the role of 14q32 microRNAs in vascular remodelling. The 14q32 microRNA cluster contains 54 microRNAs in humans and is highly conserved in mammals. In part I of this thesis, we describe the role of 14q32 microRNAs in several processes of vascular remodelling. We have shown that inhibition of several 14q32 microRNAs, miR-329, miR-494 and miR-495, results in increased neovascularisation after hindlimb ischemia in mice. In addition, inhibition of the same microRNAs reduced atherosclerotic plaque formation and restenosis in experimental mouse models under hypercholesterolemic conditions. In part II of this thesis, we zoom in to the post-transcriptional regulation of 14q32 microRNAs through RNA binding proteins. The third and last part of this thesis studies the expression of microRNAs in subcutaneous adipose tissue of critical limb ischemia patients and discusses the potential use of microRNAs as biomarker to predict the risk of amputation in these patients. In conclusion, this thesis provides novel insights in the role of 14q32 microRNAs in processes of vascular remodelling. Experimental studies have identified 14q32 microRNAs as potential therapeutic targets for treatment and prevention of atherosclerosis, restenosis and peripheral arterial disease. Show less
This thesis describes the respective contribution of the expression of Tissue factor isoforms full length Tissue Factor (flTF) and alternatively spliced Tissue Factor (asTF) as well as Factor... Show moreThis thesis describes the respective contribution of the expression of Tissue factor isoforms full length Tissue Factor (flTF) and alternatively spliced Tissue Factor (asTF) as well as Factor VII by tumor cells to promote cancer progression. Cohorts of breast, colon, and bone cancer specimens and a multitude of in vitro and in vivo models were used to explore the mechanism behind enhanced cell proliferation and metastasis in in vitro and in vivo models, as well as decreased patient survival associated with TF and FVII expression in cancer patients. Show less
The studies included in this thesis demonstrated a preclinical murine model to study neovascularization in vivo and subsequently a number of potential targets to stimulate therapeutic... Show moreThe studies included in this thesis demonstrated a preclinical murine model to study neovascularization in vivo and subsequently a number of potential targets to stimulate therapeutic neovascularization. This thesis contributes to a better insight into mechanisms underlying post-ischemic neovascularization and offers new therapeutic perspective to current treatment strategies for patients with critical limb ischemia. Whether stagnated blood flow recovery after an occlusive event is due to restricted pre-existing collateral bed or due to decreased collateral remodeling, we are now closer to a tailor made treatment available for each patient with peripheral arterial disease. Show less
In dit proefschrift worden studies besproken naar de rol van de TGF-β signaleringsroute in de tumor micro-omgeving in colorectaal kanker. Deze studies hebben zich voornamelijk gefocust op de rol... Show moreIn dit proefschrift worden studies besproken naar de rol van de TGF-β signaleringsroute in de tumor micro-omgeving in colorectaal kanker. Deze studies hebben zich voornamelijk gefocust op de rol van kanker-geassocieerde fibroblasten (CAFs) in kanker. Wij hebben aangetoond dat een co-receptor voor TGF-β, endoglin, een grote rol speelt in het CAF-gemedieerd uitzaaien van darmkanker en dat de expressie van endoglin op CAFs een prognostische marker is voor metastase-vrije overleving in vroeg stadium darmkankerpatienten. Daarnaast werd een nieuwe muizenstam ontwikkeld om specifiek op fibroblasten endoglin uit te schakelen, zodat de rol hiervan in het ontstaan van darmkanker bestudeerd kon worden in een chemisch geinduceerd model voor darmkanker. Samengevat laten de studies in dit proefschrift zien dat endoglin expressie op CAFs een belangrijke rol speelt in het metastaseren van colorectaalkanker en opent het deuren naar therapeutische toepassingen. Show less
