Project description:This study aims to investigate differentially expressed proteins in tumor pericytes with or without TCAF2-ovexpression. Tumor pericytes were isolated from tumor of patients with colorectal cancer. Then, tumor pericytes were cultured, transfected with vector or TCAF2 overexpressing plasmid. Top ten cytokines were screened and Wnt5a was the most significant one.
Project description:This study aims to investigate differentially expressed proteins in tumor pericytes derived from colorectal cancer patients with or without liver metastasis. Tumor pericytes were isolated from tumor of colorectal cancer patients with or without liver metastasis. Then, tumor pericytes were cultured and subjected to proteomic analysis. TCAF2 was significantly increased in tumor pericytes from liver metastasis patients.
Project description:Cerebral cavernous malformation (CCM) is caused by loss-of-function mutations in CCM1, CCM2, or CCM3 genes of endothelial cells. It is characterized by pericyte deficiency. However, the role of pericytes in CCMs remains poorly understood. Our study showed that pericytes in Cdh5CreERT2; Ccm1fl/fl (Ccm1ECKO) mice were high expression of PDGFRβ. The inhibition of pericyte function by CP-673451 aggravated the CCM lesion development. RNA-seq analysis revealed the molecular traits of pericytes, such as highly expressed ECM-related genes, especially Fn1. Furthermore, KLF4 coupled with phosphorylated SMAD3 promoted the transcription of fibronectin in pericytes of CCM lesions. RGDS peptide, an inhibitor of fibronectin, decreased the lesion area in the cerebella and retinas of Ccm1ECKO mice. Also, human CCM lesions had abundant fibronectin deposition, and pSMAD3- and KLF4-positive pericytes. The current data demonstrated that pericytes are essential for CCM lesion development, and fibronectin intervention may provide a novel target for therapeutic intervention in such patients.
Project description:The objective of this array was to determine the global gene expression profile of human placental pericytes for comparison with other publicly available arrays of pericytes and mesenchymal stromal cells isolated from various human tissues. Pericytes are critical cellular components of the microvasculature that play a major role in vascular development and pathologies, yet their study has been hindered by lack of a standardized method for their isolation and growth. Here we report a method for culturing human pericytes from a readily available tissue source, placenta, and provide a thorough characterization of resultant cell populations. We developed an optimized protocol for obtaining pericytes by outgrowth from microvessel fragments recovered after enzymatic digestion of human placental tissue. We characterized outgrowth populations by immunostaining, by gene expression analysis, and by functional evaluation of cells implanted in vivo. Our approach yields human pericytes that may be serially expanded in culture and that uniformly express the cellular markers NG2, CD90, CD146, α-SMA, and PDGFR-β, but lack markers of smooth muscle cells, endothelial cells, and leukocytes. When co-implanted with human endothelial cells into C.B-17 SCID/bg mice, human pericytes invest and stabilize developing human endothelial cell-lined microvessels. We conclude that our method for culturing pericytes from human placenta results in the expansion of functional pericytes that may be used to study a variety of questions related to vascular biology. Total RNA from three different pericyte isolations at subculture 1 was collected and examined for relative gene expression.
Project description:Tumor necrosis factor alpha induces vascular permeability, playing an important role in inflammation. Also, TNF-induced vascular leakage is involved in the increased extravasation of nanoparticle formulated chemotherapeutics improving drug delivery and subsequently tumor response, and we found a positive correlation between the presence of pericytes in the tumor-associated vasculature and TNF-induced leakage. RNA sequencing and pathway analysis of TNF-stimulated versus non-stimulated pericytes and endothelial cells show significant upregulation of several pathways involving interferon regulating pathways with a high expression of CXCL10, also known as Interferon gamma-inducible protein 10 (IP-10) in TNF-stimulated pericytes. In addition, CXCL10 protein production was significantly increased in conditioned medium from TNF-exposed pericytes compared to the other conditions. In our animal studies, we observed that tumor types with high pericyte covered vessels show enhanced permeability when exposed to TNF, which can be blocked with a neutralizing CXCL10 antibody. Vice versa, tumors with vessels low in pericyte number do not respond to TNF, i.e., do not express elevated permeability. Importantly, this lack of pericyte coverage can be compensated by co-administration of CXCL10. Our finding reveals a mechanism where TNF induces CXCL10 release from pericytes, being at the basis of increased permeability and thus vascular leakage.
Project description:Pericytes/vascular smooth muscle cells (VSMCs), regulated by platelet-derived growth factor receptor β (PDGFRβ) signaling, play important roles in endothelial survival and vascular stability. Here we report that treatment with imatinib, an inhibitor of PDGFRβ, led to significant tumor growth impairment associated with increased apoptosis in human lymphoma xenografts including Farage, Karpas422 and OCI-Ly7 in SCID mice. Confocal analysis of the tumor tissue showed decreased microvessel density, decreased vascular flow, and increased vascular leak in the imatinib-treated cohorts. Imatinib targeted tumor-associated PDGFRβ+ pericytes in vivo by inducing apoptosis and disruption of the PDGFRβ+ perivascular network, and PDGFRβ+ VSMC in vitro by inhibition of proliferation. FACS analysis of mononuclear cell suspension of tumor tissues revealed decreased mature pericytes and endothelial cells, as well as their progenitors with imatinib treatment. Compared to imatinib, treatment with anti-PDGFRβ monoclonal antibody partially inhibited the growth of Farage lymphomas. Lastly, microarray analysis of differentially expressed genes in PDGFRβ+ VSMC following imatinib treatment showed significant down-regulation of genes implicated in proliferation, survival and angiogenesis, including those within PI3K/AKT and MAPK/ERK1/2 pathways downstream of PDGFRβ signaling. Taken together, targeting PDGFRβ+ pericytes in lymphoma presents a novel and complementary target to endothelial cells for efficacious antiangiogenic therapy. PDGFRb+ murine vascular smooth muscle cells (VSMCs) were treated in 10 uM imatinib for 24 or 48 hours. Gene expression changes in response to imatinib treatment were examined using NimbleGen MM8_60mer gene expression microarrays by comparing expression patterns at 24- and 48-hours treatment to the baseline level (0 hours).