3,972 research outputs found
Expression site of P2RY12 in residential microglial cells in astrocytomas correlates with M1 and M2 marker expression and tumor grade
The role of resident microglial cells in the pathogenesis and progression of glial tumors is still obscure mainly due to a lack of specific markers. Recently P2RY12, a P2 purinergic receptor, was introduced as a specific marker for microglial cells under normal and pathologic conditions. Here we analyzed the expression of P2RY12 in astrocytomas of various malignancy grades in relation to markers for M1 and M2 macrophage activation profiles by using two web-based glioma datasets and confocal immunohistochemistry to 28 astrocytoma samples grades II-IV. In the gliomas, P2RY12 immunoreactivity delineated CD68 negative cells with otherwise microglial features from CD68 positive tumor associated macrophages (TAMs). The presence of P2RY12 positive cells correlated positively with overall survival. P2RY12 mRNA levels and membrane-bound localization of P2RY12 were inversely correlated with increasing malignancy grade, and the expression site of P2RY12 shifted from cytoplasmic in low-grade gliomas, to nuclear in high-grade tumors. The cytoplasmic expression of P2RY12 was associated with the expression of M1 markers, characteristic of the pro-inflammatory macrophage response. In contrast, the nuclear localization of P2RY12 was predominant in the higher graded tumors and associated with the expression of the M2 marker CD163. We conclude that P2RY12 is a specific marker for resident microglia in glioma and its expression and localization correspond to tumor grade and predominant stage of M1/M2 immune response
Cardiorenal disease connection during post-menopause: The protective role of estrogen in uremic toxins induced microvascular dysfunction
Female gender, post-menopause, chronic kidney disease (CKD) and (CKD linked) microvascular disease are important risk factors for developing heart failure with preserved ejection fraction (HFpEF). Enhancing our understanding of the interrelation between these risk factors could greatly benefit the identification of new drug targets for future therapy. This review discusses the evidence for the protective role of estradiol (E2) in CKD-associated microvascular disease and related HFpEF. Elevated circulating levels of uremic toxins (UTs) during CKD may act in synergy with hormonal changes during post-menopause and could lead to coronary microvascular endothelial dysfunction in HFpEF. To elucidate the molecular mechanism involved, published transcriptome datasets of indoxyl sulfate (IS), high inorganic phosphate (HP) or E2 treated human derived endothelial cells from the NCBI Gene Expression Omnibus database were analyzed. In total, 36 genes overlapped in both IS- and HP-activated gene sets, 188 genes were increased by UTs (HP and/or IS) and decreased by E2, and 572 genes were decreased by UTs and increased by E2. Based on a comprehensive in silico analysis and literature studies of collected gene sets, we conclude that CKD-accumulated UTs could negatively impact renal and cardiac endothelial homeostasis by triggering extensive inflammatory responses and initiating dysregulation of angiogenesis. E2 may protect (myo)endothelium by inhibiting UTs-induced inflammation and ameliorating UTs-related uremic bleeding and thrombotic diathesis via restored coagulation capacity and hemostasis in injured vessels
CECR1-mediated cross talk between macrophages and vascular mural cells promotes neovascularization in malignant glioma
Glioblastomas (glioblastoma multiforme, GBM) are most malignant brain tumors characterized by profound vascularization. The activation of macrophages strongly contributes to tumor angiogenesis during GBM development. Previously, we showed that extracellular adenosine deaminase protein Cat Eye Syndrome Critical Region Protein 1 (CECR1) is highly expressed by M2-like macrophages in GBM where it defines macrophage M2 polarization and contributes to tumor expansion. In this study, the effect of CECR1 in macrophages on tumor angiogenesis was investigated. Immunohistochemical evaluation of GBM tissue samples showed that the expression of CECR1 correlates with microvascular density in the tumors, confirming data from the TCGA set. In a three-dimensional co-culture system consisting of human pericytes, human umbilical vein endothelial cells and THP1-derived macrophages, CECR1 knockdown by siRNA and CECR1 stimulation of macrophages inhibited and promoted new vessel formation, respectively. Loss and gain of function studies demonstrated that PDGFB mRNA and protein levels in macrophages are modulated by CECR1. The proangiogenic properties of CECR1 in macrophages were partially mediated via paracrine activation of pericytes by PDGFB–PDGFRβ signaling. CECR1–PDGFB–PDGFRβ cross-activation between macrophages and pericytes promoted pericyte migration, shown by transwell migration assay, and enhanced expression and deposition of periostin, a matrix component with proangiogenic properties. CECR1 function in (M2-like) macrophages mediates cross talk between macrophages and pericytes in GBM via paracrine PDGFB–PDGFRβ signaling, promoting pericyte recruitment and migration, and tumor angiogenesis. Therefore, CECR1 offers a new portent target for anti-angiogenic therapy in GBM via immune modulation.Oncogene advance online publication, 22 May 2017; doi:10.1038/onc.2017.145
Altered purinergic signaling in uridine adenosine tetraphosphate-induced coronary relaxation in swine with metabolic derangement
We previously demonstrated that uridine adenosine tetraphosphate (Up4A) induces potent and partially endothelium-dependent relaxation in the healthy porcine coronary microvasculature. We subsequently showed that Up4A-induced porcine coronary relaxation was impaired via downregulation of P1 receptors
Endothelial loss of Fzd5 stimulates PKC/Ets1-mediated transcription of Angpt2 and Flt1
Aims: Formation of a functional vascular system is essential and its formation is a highly regulated process initiated during embryogenesis, which continues to play important roles throughout life in both health and disease. In previous studies, Fzd5 was shown to be critically involved in this process and here we investigated the molecular mechanism by which endothelial loss of this receptor attenuates angiogenesis. Methods and results: Using short interference RNA-mediated loss-of-function assays, the function and mechanism of signaling via Fzd5 was studied in human endothelial cells (ECs). Our findings indicate that Fzd5 signaling promotes neovessel formation in vitro in a collagen matrix-based 3D co-culture of primary vascular cells. Silencing of Fzd5 reduced EC proliferation, as a result of G0/G1 cell cycle arrest, and decreased cell migration. Furthermore, Fzd5 knockdown resulted in enhanced expression of the factors Angpt2 and Flt1, which are mainly known for their destabilizing effects on the vasculature. In Fzd5-silenced ECs, Angpt2 and Flt1 upregulation was induced by enhanced PKC signaling, without the involvement of canonical Wnt signaling, non-canonical Wnt/Ca2+-mediated activation of NFAT, and non-canonical Wnt/PCP-mediated activation of JNK. We demonstrated that PKC-induced transcription of Angpt2 and Flt1 involved the transcription factor Ets1. Conclusions: The current study demonstrates a pro-angiogenic role of Fzd5, which was shown to be involved in endothelial tubule formation, cell cycle progression and migration, and partly does so by repression of PKC/Ets1-mediated transcription of Flt1 and Angpt2
Meta-analysis of genome-wide association studies from the CHARGE consortium identifies common variants associated with carotid intima media thickness and plaque
Carotid intima media thickness (cIMT) and plaque determined by ultrasonography are established measures of subclinical atherosclerosis that each predicts future cardiovascular disease events. We conducted a meta-analysis of genome-wide association data in 31,211 participants of European ancestry from nine large studies in the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. We then sought additional evidence to support our findings among 11,273 individuals using data from seven additional studies. In the combined meta-analysis, we identified three genomic regions associated with common carotid intima media thickness and two different regions associated with the presence of carotid plaque (P < 5 × 10 -8). The associated SNPs mapped in or near genes related to cellular signaling, lipid metabolism and blood pressure homeostasis, and two of the regions were associated with coronary artery disease (P < 0.006) in the Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) consortium. Our findings may provide new insight into pathways leading to subclinical atherosclerosis and subsequent cardiovascular events
The Sheer Stress of Shear Stress: Responses of the Vascular Wall to a Haemodynamic Force
Studies in the hemodynamic field point to a strong relation between shear stress and
the onset to vascular diseases such as atherosclerosis. Data from in vitro studies using
sheared endothelial cells have provided insight into the possible mechanisms
involved. However, the lack of an appropriate in vivo model to introduce pro-
atherogenic shear stress parameters has hampered investigation of the effects of this
hemodynamic force on the vessel wall. In this thesis, we developed and validated a
new shear stess model to be applied in vivo. We studied the effects of low, high and
oscillatory shear stress on the pathology of atherosclerosis
Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas
Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN
Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images
Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images
of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL
maps are derived through computational staining using a convolutional neural network trained to
classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and
correlation with overall survival. TIL map structural patterns were grouped using standard
histopathological parameters. These patterns are enriched in particular T cell subpopulations
derived from molecular measures. TIL densities and spatial structure were differentially enriched
among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial
infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic
patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for
the TCGA image archives with insights into the tumor-immune microenvironment
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
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