Project description:In the past decade, the relevance of tumor-induced lymphangiogenesis for the metastatic spread of tumor cells has been demonstrated, thus indicating the potential of targeting tumor lymphangiogenesis to treat cancer. Whereas numerous preclinical studies demonstrated that blocking angiogenesis or lymphangiogenesis could inhibit tumor metastasis, the scarcity of highly selective targeting candidates hampers their translation to the clinic. We employed a new approach consisting of immuno-laser capture microdissection (i-LCM) and transcriptional profiling by means of microarrays in order to identify novel tumor-specific endothelial markers. By using short immunostainings prior to microdissection, specific identification of lymphatic (LECs) and blood (BECs) endothelial cells was allowed. For the subsequent gene expression profiling, a single round of the Ribo-Spia amplification method in combination with the Affymterix microarray platform was used. Comparison of gene expression profiles of tumor-associated and normal LECs resulted in the identification of differentially expressed genes in tumor-associated lymphatic vasculature.
Project description:This is an investigation of whole genome gene expression level in tissues of mice stimulated by LPS, FK565 or LPS + FK565 in vivo and ex vivo. We show that parenteral administration of a pure synthetic Nod1 ligand, FK565, induces site-specific vascular inflammation in mice, which is prominent in aortic root including aortic valves, slight in aorta and absent in other arteries. The degree of respective vascular inflammation is associated with persistent high expression of proinflammatory chemokine/cytokine genes in each tissue in vivo by microarray analysis, and not with Nod1 expression levels. The ex vivo production of proinflammatory chemokine/cytokine by Nod1 ligand is higher in aortic root than in other arteries from normal murine vascular tissues, and also higher in human coronary artery endothelial cells (HCAEC) than in human pulmonary artery endothelial cells (HPAEC), suggesting that site-specific vascular inflammation is at least in part ascribed to an intrinsic nature of the vascular tissue/cell itself.
Project description:Trafficking of leukocytes (dendritic cells, memory T cells, neutrophils) and tumor cells through the lymphatic network is a key process in inflammation and immunity and an important mechanism in metastatic spread of human cancers (1-3). Such trafficking involves both communication with and passage across lymphatic endothelium, the distinct endothelium that lines lymphatic vessels within the peripheral tissues and forms the lymphatic sinuses within lymph nodes. However, in comparison with blood vascular endothelium, there is only a rudimentary understanding of the molecular phenotype of lymphatic endothelium, and only a basic knowledge of the glycoconjugates that regulate leukocyte-endothelial and tumor cell-endothelial interactions in the lymphatic compartment. We would anticipate that changes in glycosylation of LEC cell surface proteins following activation might affect important functions associated withy LEC including eg. interactions with leukocytes and/or sequestration of GAG-binding chemokines. We already have shown that ligand binding to the lymphatic endothelial hyaluronan receptor LYVE-1 is reversibly masked by terminal sialation in LEC and that functional regulation of LYVE-1 is likely to be important in inflammation. An advantage of our proposal is that we can routinely isolate primary LEC in relatively large numbers, and have the necessary ethical approval to do so from human tissue. Glycan analysis of primary human lymphatic endothelial cells (LEC) in their resting and activated states, in normal and tumour tissues and a comparison of the LEC glycan structures with those from blood vessel endothelial cells
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from Mus musculus tissues (Heart, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
Project description:Invasion of lymphatic vessels is a key step in the metastasis of primary tumour cells to draining lymph nodes. Recent evidence indicates that such metastasis can be facilitated by tumour lymphangiogenesis, although it remains unclear whether this is a consequence of increased lymphatic vessel numbers or alteration in the properties of the vessels themselves. Here we have addressed this important question by comparing the RNA profile of normal dermal lymphatic endothelial cells (LEC) with those isolated from tumours of murine T-241/VEGF-C metastatic fibrosarcoma. Our findings reveal significant changes in the expression of some 792 genes in tumour lymphatics (≥ 2 fold up/downregulation, p ≤ 0.05), involving particularly transcripts associated with junctional adhesion, immunomodulation, extracellular matrix and vessel growth/patterning, several of which we have confirmed by RT-PCR and/or immunohistochemistry. Interestingly, this altered phenotype could not be attributed solely to VEGF-C induced lymphoproliferation, as no similar change in gene expression was reported when human LEC were cultured with VEGF-C in vitro. Moreover, we show that a key protein upregulated in the mouse model, namely the tight junction protein Endothelial Cell Specific Adhesion Molecule (ESAM), is similarly upregulated in tumour lymphatic vessels from 2/2 patients with head and neck squamous cell carcinoma and 4/4 patients with aggressive bladder carcinoma. These findings demonstrate a previously unrecognized influence of tumour environment on lymphatic gene expression and identify candidate tumour specific vessel markers that may prove valuable for either prognosis or therapy. Keywords: Tumor, Metastasis, Lymphatic endothelium, comparative transcriptional profiling
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from seven Mus musculus tissues (Heart, Brain, Liver, Lung, Kidney, Skeletal Muscle, Thymus)