ADAMTS1 alters blood vessel morphology and TSP1 levels in LNCaP and LNCaP-19 prostate tumors

<p>Abstract</p> <p>Background</p> <p>Decreased expression of the angiogenesis inhibitor ADAMTS1 (ADAM metallopeptidase with thrombospondin type 1 motif, 1) has previously been reported during prostate cancer progression. The aim of this study was to investigate the function of ADAMTS1 in prostate tumors.</p> <p>Methods</p> <p>ADAMTS1 was downregulated by shRNA technology in the human prostate cancer cell line LNCaP (androgen-dependent), originally expressing ADAMTS1, and was upregulated by transfection in its subline LNCaP-19 (androgen-independent), expressing low levels of ADAMTS1. Cells were implanted subcutaneously in nude mice and tumor growth, microvessel density (MVD), blood vessel morphology, pericyte coverage and thrombospondin 1 (TSP1) were studied in the tumor xenografts.</p> <p>Results</p> <p>Modified expression of ADAMTS1 resulted in altered blood vessel morphology in the tumors. Low expression levels of ADAMTS1 were associated with small diameter blood vessels both in LNCaP and LNCaP-19 tumors, while high levels of ADAMTS1 were associated with larger vessels. In addition, TSP1 levels in the tumor xenografts were inversely related to ADAMTS1 expression. MVD and pericyte coverage were not affected. Moreover, upregulation of ADAMTS1 inhibited tumor growth of LNCaP-19, as evidenced by delayed tumor establishment. In contrast, downregulation of ADAMTS1 in LNCaP resulted in reduced tumor growth rate.</p> <p>Conclusions</p> <p>The present study demonstrates that ADAMTS1 is an important regulatory factor of angiogenesis and tumor growth in prostate tumors, where modified ADAMTS1 expression resulted in markedly changed blood vessel morphology, possibly related to altered TSP1 levels.</p

Endothelial Inflammation and Neutrophil Transmigration Are Modulated by Extracellular Matrix Composition in an Inflammation-on-a-chip Model

Inflammatory diseases are often characterised by excessive neutrophil infiltration from the blood stream to the site of inflammation, which damages healthy tissue and prevents resolution of inflammation. Development of anti-inflammatory drugs is hindered by lack of in vitro and in vivo models which accurately represent the disease microenvironment. In this study, we used the OrganoPlate to develop a humanized 3D in vitro inflammation-on-a-chip model to recapitulate neutrophil transmigration across the endothelium and subsequent migration through the extracellular matrix (ECM). Human umbilical vein endothelial cells formed confluent vessels against collagen I and geltrex mix, a mix of basement membrane extract and collagen I. TNF-α-stimulation of vessels upregulated inflammatory cytokine expression and promoted neutrophil transmigration. Intriguingly, major differences were found depending on the composition of the ECM. Neutrophils transmigrated in higher number and further in geltrex mix than collagen I, and did not require an N-formyl-methionyl-leucyl-phenylalanine (fMLP) gradient for transmigration. Inhibition of neutrophil proteases inhibited neutrophil transmigration on geltrex mix, but not collagen I. These findings highlight the important role of the ECM in determining cell phenotype and response to inhibitors. Future work could adapt the ECM composition for individual diseases, producing accurate models for drug development.AstraZeneca-Cambridge PhD Studentshi

Inhibition of metastasis in a castration resistant prostate cancer model by the quinoline-3-carboxamide tasquinimod (ABR-215050)

BACKGROUND Tasquinimod (ABR-215050) is an orally active quinoline-3-carboxamide analog that has completed phase II clinical trial in patients with castration resistant prostate cancer, showing promising inhibiting effects on the occurrence of metastasis and delayed disease progression. Its mechanism of action is not fully elucidated, but previous studies show anti-angiogenic effects and strong interaction with the S100A9 protein. METHODS This study was performed to evaluate if tasquinimod inhibits prostate cancer metastasis, by using both orthotopic and intratibial xenograft models. Animals were treated with tasquinimod, and tumor growth characteristics as well as molecular markers for metastasis and angiogenesis were analyzed. RESULTS The results show that formation of lung and lymph node metastases from orthotopic castration resistant prostate tumors was inhibited by tasquinimod treatment. Importantly, establishment of tumors in the bone after intratibial implantation was suppressed by tasquinimod. In addition, establishment and growth of subcutaneous tumors were affected. Both in primary tumors and serum from treated mice an upregulation of thrombospondin 1 was observed. Further, downregulation of the hypoxia driven genes VEGF, CXCR4, and LOX was detected in the primary tasquinimod-treated tumors and decreased expression of chemotactic ligand SDF-1 was demonstrated in the lungs. Thus, these molecular changes could contribute to the anti-angiogenic and anti-metastatic effects of tasquinimod. CONCLUSIONS In conclusion, this study and clinical data show that tasquinimod interferes with the metastatic process, presumably by inhibition of tumor establishment. Therefore, tasquinimod is an interesting treatment option for patients with prostate cancer prone to metastasis. Prostate 72:913924, 2012. (C) 2011 Wiley Periodicals, Inc

A multicellular vessel-on-a-chip model reveals context-dependent roles for platelets in inflammation and inflammatory hemostasis

The immune system identifies and destroys invading pathogens. However, chronic inflammation and excessive tissue damage can result if inflammation is not resolved or if the immune system misidentifies a threat. Therefore, the immune system must be tightly controlled. However, the complex cell-cell and cell-microenvironment interactions that regulate immune cell recruitment are challenging to recapitulate in 2D in vitro models, and poorly representative of human physiology in in vivo animal models. Organ-on-a-chip technology has the potential to overcome these limitations and provide powerful pre-clinical models. In this study, we developed a vessel-on-a-chip model to investigate the role of platelets in inflammation and inflammatory hemostasis. Endothelial vessels cultured in the OrganoPlate exhibited physiological barrier function to macromolecules and red blood cells (RBCs), which was enhanced by platelets. Cytokine stimulation increased vessel permeability and induced neutrophil transmigration. Leakage of RBCs occurred at sites of inflammation and/or neutrophil transmigration, depending on the ECM composition. Addition of platelets prevented RBC leakage at these sites, whilst simultaneously increasing permeability and neutrophil transmigration, demonstrating the multifaceted role of platelets in inflammatory hemostasis. In angiogenic neo-vessels, platelets played a protective role, preventing leakage of both small molecules and RBCs. Together, our model successfully recapitulated the modulation of endothelial barrier function and inflammation by platelets, and demonstrated the feasibility of investigating complex cellular interactions in in vitro models

The Combination of Vascular Endothelial Growth Factor A (VEGF-A) and Fibroblast Growth Factor 1 (FGF1) Modified mRNA Improves Wound Healing in Diabetic Mice: An Ex Vivo and In Vivo Investigation

Background: Diabetic foot ulcers (DFU) pose a significant health risk in diabetic patients, with insufficient revascularization during wound healing being the primary cause. This study aimed to assess microvessel sprouting and wound healing capabilities using vascular endothelial growth factor (VEGF-A) and a modified fibroblast growth factor (FGF1). Methods: An ex vivo aortic ring rodent model and an in vivo wound healing model in diabetic mice were employed to evaluate the microvessel sprouting and wound healing capabilities of VEGF-A and a modified FGF1 both as monotherapies and in combination. Results: The combination of VEGF-A and FGF1 demonstrated increased vascular sprouting in the ex vivo mouse aortic ring model, and topical administration of a combination of VEGF-A and FGF1 mRNAs formulated in lipid nanoparticles (LNPs) in mouse skin wounds promoted faster wound closure and increased neovascularization seven days post-surgical wound creation. RNA-sequencing analysis of skin samples at day three post-wound creation revealed a strong transcriptional response of the wound healing process, with the combined treatment showing significant enrichment of genes linked to skin growth. Conclusion: f-LNPs encapsulating VEGF-A and FGF1 mRNAs present a promising approach to improving the scarring process in DFU