Suchergebnisse

Zebrafish, an amenable small teleost fish with a complex mammal-like circulatory system, is being increasingly used for drug screening and toxicity studies. It combines the biological complexity of in vivo models with a higher-throughput screening capability compared with other available animal models. Externally growing, transparent embryos, displaying well-defined blood and lymphatic vessels, allow the inexpensive, rapid, and automatable evaluation of drug candidates that are able to inhibit neovascularisation. Here, we briefly review zebrafish as a model for the screening of anti(lymph) angiogenic drugs, with emphasis on the advantages and limitations of the different zebrafish-based in vivo assays. ; Our experimental work was supported by grants BIO2014-56092-R (Spanish Ministry of Economy and Competitiveness and FEDER), and PIE P12-CTS-1507,CVI-6585 and funds from group BIO-267 (Andalucian Government and FEDER). CIBER de Enfermedades Raras and CIBER de Bioingenierı´a, Biomateriales y Nanomedicina are initiatives from the ISCIII (Spain). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.

In the course of a screening program for the inhibitors of angiogenesis from marine sources, AD0157, a pyrrolidinedione fungal metabolite, was selected for its angiosupressive properties. AD0157 inhibited the growth of endothelial and tumor cells in culture in the micromolar range. Our results show that subtoxic doses of this compound inhibit certain functions of endothelial cells, namely, differentiation, migration and proteolytic capability. Inhibition of the mentioned essential steps of in vitro angiogenesis is in agreement with the observed antiangiogenic activity, substantiated by using two in vivo angiogenesis models, the chorioallantoic membrane and the zebrafish embryo neovascularization assays, and by the ex vivo mouse aortic ring assay. Our data indicate that AD0157 induces apoptosis in endothelial cells through chromatin condensation, DNA fragmentation, increases in the subG1 peak and caspase activation. The data shown here altogether indicate for the first time that AD0157 displays antiangiogenic effects, both in vitro and in vivo, that are exerted partly by targeting the Akt signaling pathway in activated endothelial cells. The fact that these effects are carried out at lower concentrations than those required for other inhibitors of angiogenesis makes AD0157 a new promising drug candidate for further evaluation in the treatment of cancer and other angiogenesis-related pathologies. [Our experimental work is supported by grant P12-CTS-1507 (Andalusian Government and FEDER) and funds from group BIO-267 (Andalusian Government). The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain). This communication has the support of a travel grant "Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech"]. ; Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

BACKGROUND AND PURPOSE Lymphangiogenesis is an important biological process associated with the pathogenesis of several diseases, including metastatic dissemination, graft rejection, lymphoedema and other inflammatory disorders. The development of new drugs that block lymphangiogenesis has become a promising therapeutic strategy. In this study, we investigated the ability of toluquinol, a 2-methyl-hydroquinone isolated from the culture broth of the marine fungus Penicillium sp. HL-85-ALS5-R004, to inhibit lymphangiogenesis in vitro, ex vivo and in vivo. EXPERIMENTAL APPROACH We used human lymphatic endothelial cells (LECs) to analyse the effect of toluquinol in 2D and 3D in vitro cultures and in the ex vivo mouse lymphatic ring assay. For in vivo approaches, the transgenic Fli1:eGFPy1 zebrafish, mouse ear sponges and cornea models were used. Western blotting and apoptosis analyses were carried out to search for drug targets. KEY RESULTS Toluquinol inhibited LEC proliferation,migration, tubulogenesis and sprouting of new lymphatic vessels. Furthermore, toluquinol induced apoptosis of LECs after 14 h of treatment in vitro, blocked the development of the thoracic duct in zebrafish and reduced the VEGF-C-induced lymphatic vessel formation and corneal neovascularization in mice. Mechanistically, we demonstrated that this drug attenuates VEGF-C-induced VEGFR-3 phosphorylation in a dose-dependentmanner and suppresses the phosphorylation of Akt and ERK1/2. CONCLUSIONS AND IMPLICATIONS Based on these findings, we propose toluquinol as a new candidate with pharmacological potential for the treatment of lymphangiogenesis-related pathologies. Notably, its ability to suppress corneal neovascularization paves the way for applications in vascular ocular pathologies. ; Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work has been supported by personal funding by FP7-PEOPLE-2013-IEF Marie Curie Postdoctoral Fellowship (MGC). Acknowledged are the supporting grants from the Action de Recherche Concertée (ARC) (Université de Liège), the Fonds de la Recherche Scientifique-FNRS (F.R.S.-FNRS), the Foundation Against Cancer (foundation of public interest), the Centre Anticancéreux près l'Université de Liège, the Fonds Léon Fredericq (University of Liège), the Interuniversity Attraction Poles Programme-Belgian Science Policy (all from Belgium) and the Plan National Cancer (« Service Public Federal » from Belgium). Research in the lab of A.R.Q. and M.A.M. was supported by grants BIO2014-56092-R (MINECO and FEDER) and P12-CTS-1507 (Andalusian Government and FEDER).

The tropical plant Annona muricata has been widely used for traditional ethnobotanic and pharmacologic applications. Extracts from different parts of this plant have been shown to have a wide range of biological activities. In the present study, we carry out a metabolomic study of both aqueous and DMSO extracts from Annona muricata leaves that has allowed us to identify 33 bioactive compounds. Furthermore, we have shown that aqueous extracts are able to inhibit endothelial cell migration and both aqueous and DMSO extracts inhibit the formation of tubule-like structures by endothelial cells cultured on Matrigel. We conclude that extracts of Annona muricata leaves have great potential as anti-angiogenic natural combinations of bioactive compounds. ; Funding for open access charge: Universidad de Málaga / CBUA. This work was supported by grants PID2019-105010RB-I00 (Spanish Ministry of Science, Innovation and Universities), UMA18-FEDERJA220, UMA18-FEDERJA-267 and PY20_00257 (Andalusian Government and FEDER) and funds from group BIO 267 (Andalusian Government). The "CIBER de Enfermedades Raras" and "CIBER de Enfermedades Vasculares" are initiatives from the ISCIII (Spain). The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript.

Tumor vessel co-option is poorly understood, yet it is a resistance mechanism against anti-angiogenic therapy (AAT). The heterogeneity of co-opted endothelial cells (ECs) and pericytes, co-opting cancer and myeloid cells in tumors growing via vessel co-option, has not been investigated at the single-cell level. Here, we use a murine AAT-resistant lung tumor model, in which VEGF-targeting induces vessel co-option for continued growth. Single-cell RNA sequencing (scRNA-seq) of 31,964 cells reveals, unexpectedly, a largely similar transcriptome of co-opted tumor ECs (TECs) and pericytes as their healthy counterparts. Notably, we identify cell types that might contribute to vessel co-option, i.e., an invasive cancer-cell subtype, possibly assisted by a matrix-remodeling macrophage population, and another M1-like macrophage subtype, possibly involved in keeping or rendering vascular cells quiescent. ; L.-A.T., L.D., S.V.L., and P.V. are supported by Fonds Oncologie Augustinus-Koning Boudewijnstichting and GZA Ziekenhuizen; A.C., K.R., N.V.C., L.P.M.H.d.R., and L.T. by the Fonds Wetenschappelijk Onderzoek (FWO); S.J.D. by a Marie Curie-IEF fellowship; V.G. by Strategisch Basisonderzoek FWO (SB-FWO); Y.L. by BGI-Research, Danish Research Council for Independent Research (DFF-1337-00128), Sapere Aude Young Research Talent Prize (DFF-1335–00763A), and Aarhus University Strategic Grant (AU-iCRISPR); and P.C. by Methusalem funding (Flemish government), Fund for Scientific Research-Flanders (FWO-Vlaanderen), Foundation Against Cancer (2016-078), Kom op tegen Kanker (Stand up to Cancer, Flemish Cancer Society), European Research Council (ERC Proof of Concept grant ERC-713758 and Advanced ERC Research grant EU-ERC743074), and a NNF Laureate Research Grant from Novo Nordisk Foundation (NNF19OC0055802). ; Yes