A Significant Regulatory Mutation Burden at a High-Affinity Position of the CTCF Motif in Gastrointestinal Cancers

2016 ◽  
Vol 37 (9) ◽  
pp. 904-913 ◽  
Author(s):  
Husen M. Umer ◽  
Marco Cavalli ◽  
Michal J. Dabrowski ◽  
Klev Diamanti ◽  
Marcin Kruczyk ◽  
...  
Epigenomics ◽  
2020 ◽  
Author(s):  
Qijie Zhao ◽  
Jinan Guo ◽  
Yueshui Zhao ◽  
Jing Shen ◽  
Parham Jabbarzadeh Kaboli ◽  
...  

Background: PD-L1 and PD-L2 are ligands of PD-1. Their overexpression has been reported in different cancers. However, the underlying mechanism of PD-L1 and PD-L2 dysregulation and their related signaling pathways are still unclear in gastrointestinal cancers. Materials & methods: The expression of PD-L1 and PD-L2 were studied in The Cancer Genome Atlas and Genotype-Tissue Expression databases. The gene and protein alteration of PD-L1 and PD-L2 were analyzed in cBioportal. The direct transcription factor regulating PD-L1/ PD-L2 was determined with ChIP-seq data. The association of PD-L1/PD-L2 expression with clinicopathological parameters, survival, immune infiltration and tumor mutation burden were investigated with data from The Cancer Genome Atlas. Potential targets and pathways of PD-L1 and PD-L2 were determined by protein enrichment, WebGestalt and gene ontology. Results: Comprehensive analysis revealed that PD-L1 and PD-L2 were significantly upregulated in most types of gastrointestinal cancers and their expressions were positively correlated. SP1 was a key transcription factor regulating the expression of PD-L1. Conclusion: Higher PD-L1 or PD-L2 expression was significantly associated with poor overall survival, higher tumor mutation burden and more immune and stromal cell populations. Finally, HIF-1, ERBB and mTOR signaling pathways were most significantly affected by PD-L1 and PD-L2 dysregulation. Altogether, this study provided comprehensive analysis of the dysregulation of PD-L1 and PD-L2, its underlying mechanism and downstream pathways, which add to the knowledge of manipulating PD-L1/PD-L2 for cancer immunotherapy.


PLoS ONE ◽  
2018 ◽  
Vol 13 (2) ◽  
pp. e0192194 ◽  
Author(s):  
Aleksandra Borek ◽  
Aleksandra Sokolowska-Wedzina ◽  
Grzegorz Chodaczek ◽  
Jacek Otlewski

Author(s):  
Martin Hagopian ◽  
Michael D. Gershon ◽  
Eladio A. Nunez

The ability of cardiac tissues to take up norepinephrine from an external medium is well known. Two mechanisms, called Uptake and Uptake respectively by Iversen have been differentiated. Uptake is a high affinity system associated with adrenergic neuronal elements. Uptake is a low affinity system, with a higher maximum rate than that of Uptake. Uptake has been associated with extraneuronal tissues such as cardiac muscle, fibroblasts or vascular smooth muscle. At low perfusion concentrations of norepinephrine most of the amine taken up by Uptake is metabolized. In order to study the localization of sites of norepinephrine storage following its uptake in the active bat heart, tritiated norepinephrine (2.5 mCi; 0.064 mg) was given intravenously to 2 bats. Monoamine oxidase had been inhibited with pheniprazine (10 mg/kg) one hour previously to decrease metabolism of norepinephrine.


2019 ◽  
Vol 10 (02) ◽  
pp. 67-67
Author(s):  
Alexander Kretzschmar

Gallengangskarzinome treten selten auf und weisen eine sehr schlechte Prognose auf. In einer auf dem Gastrointestinal Cancers Symposium (GICS) vorgestellten offenen Phase-II-Studie führte die Kombination der BRAF- and MEK-Inhibitoren Dabrafenib und Trametinib zu einer objektiven Responserate (ORR) als primärem Endpunkt von 41 % (13/32; 95 % Konfidenzintervall [KI] 24–59 %), so Prof. Zev A. Wainberg, Los Angeles/USA.


2019 ◽  
Vol 10 (02) ◽  
pp. 60-61
Author(s):  
Ine Schmale

Während bei vielen Tumorentitäten große Fortschritte in der Behandlung zu berichten sind, bleibt das Pankreaskarzinom ein Tumor mit einer schlechten Prognose und wenigen Therapieoptionen. Beim Gastrointestinal Cancers Symposium (ASCO­GI) wurde eine Sitzung der frühen Detektion, der Sequenztherapie resektabler Tumoren und den Therapien der Zukunft beim Pankreaskarzinom gewidmet.


1978 ◽  
Vol 17 (04) ◽  
pp. 161-171
Author(s):  
H.-J. Engel ◽  
H. Hundeshagen ◽  
P. R. Lichtlen

Methodological and technical aspects as well as application and results of the precordial Xenon-residue-detection technique are critically reviewed. The results concern mainly normal flow in various regions of the heart esp. in the free wall of the right and left ventricle, poststenotic flow in patients with coronary artery disease in relation to the degree of proximal nar-rowings as well as wall motion of the corresponding LV segment, bypassgraft flow and flow after drug interventions esp. nitrates, betablockers, the calcium-antagonist Nifedipine and the coronary dilator Dipyridamole. In spite of its serious limitations (high affinity of Xenon for fatty tissue, geometrical problems in the assessment of flow and its relation to anatomy, gas exchange in situations of high flow etc.), the technique is found to be a usefull investigatory tool. Due to its technical display and the related high costs routine application is, however, prohibitive.


1987 ◽  
Vol 26 (05) ◽  
pp. 224-228 ◽  
Author(s):  
Y. Isaka ◽  
H. Etani ◽  
K. Kimura ◽  
S. Yoneda ◽  
T. Kamada ◽  
...  

Tissue-type plasminogen activator (t-PA) which has a high affinity for fibrin in the clot, was labeled with 131I by the iodogen method, and its binding to de-endothelialized lesions in the rabbit was measured to assess the detectability of thrombi. The de-endothelialized lesion was induced in the abdominal aorta with a Fogarty 4F balloon catheter. Two hours after the de-endothelialization, 131I-labeled t-PA (125 ± 46 μCi) was injected intravenously. The initial half-life of the agent in blood (n = 12) was 2.9 ± 0.4 min. The degree of binding of 131I-labeled t-PA to the de-endothelialized lesion was evaluated at 15 min (n = 6) or at 30 min (n = 6) after injection of the agent. In spite of the retention of the biochemical properties of 131I-labeled t-PA and the presence of fibrin deposition at the de-endothelialized lesion, the binding of t-PA to the lesion was not sufficiently strong. Lesion-to-control ratios (cpm/g/cpm/g) were 1.65 ± 0.40 (at 15 min) and 1.39 ± 1.31 (at 30 min), and lesion-to-blood ratios were 1.39 ± 0.32 (at 15 min) and 1.36 ± 0.23 (at 30 min). These results suggest that radiolabeled t-PA may be inappropriate as a radiopharmaceutical for the scintigraphic detection of a pre-existing thrombotic lesion.


1990 ◽  
Vol 63 (02) ◽  
pp. 193-203 ◽  
Author(s):  
John R Shainoff ◽  
Deborah J Stearns ◽  
Patricia M DiBello ◽  
Youko Hishikawa-Itoh

SummaryThe studies reported here probe the existence of a receptor-mediated mode of fibrin-binding by macrophages that is associated with the chemical change underlying the fibrinogen-fibrin conversion (the release of fibrinopeptides from the amino-terminal domain) without depending on fibrin-aggregation. The question is pursued by 1) characterization of binding in relation to fibrinopeptide content of both the intact protein and the CNBr-fragment comprising the amino-terminal domain known as the NDSK of the protein, 2) tests of competition for binding sites, and 3) photo-affinity labeling of macrophage surface proteins. The binding of intact monomers of types lacking either fibrinopeptide A alone (α-fibrin) or both fibrinopeptides A and B (αβ-fibrin) by peritoneal macrophages is characterized as proceeding through both a fibrin-specific low density/high affinity (BMAX ≃ 200–800 molecules/cell, KD ≃ 10−12 M) interaction that is not duplicated with fibrinogen, and a non-specific high density/low affinity (BMAX ≥ 105 molecules/cell, KD ≥ 10−6 M) interaction equivalent to the weak binding of fibrinogen. Similar binding characteristics are displayed by monocyte/macrophage cell lines (J774A.1 and U937) as well as peritoneal macrophages towards the NDSK preparations of these proteins, except for a slightly weaker (KD ≃ 10−10 M) high-affinity binding. The high affinity binding of intact monomer is inhibitable by fibrin-NDSK, but not fibrinogen-NDSK. This binding appears principally dependent on release of fibrinopeptide-A, because a species of fibrin (β-fibrin) lacking fibrinopeptide-B alone undergoes only weak binding similar to that of fibrinogen. Synthetic Gly-Pro-Arg and Gly-His-Arg-Pro corresponding to the N-termini of to the α- and the β-chains of fibrin both inhibit the high affinity binding of the fibrin-NDSKs, and the cell-adhesion peptide Arg-Gly-Asp does not. Photoaffinity-labeling experiments indicate that polypeptides with elec-trophoretically estimated masses of 124 and 187 kDa are the principal membrane components associated with specifically bound fibrin-NDSK. The binding could not be up-regulated with either phorbol myristyl acetate, interferon gamma or ADP, but was abolished by EDTA and by lipopolysaccharide. Because of the low BMAX, it is suggested that the high-affinity mode of binding characterized here would be too limited to function by itself in scavenging much fibrin, but may act cooperatively with other, less limited modes of fibrin binding.


1991 ◽  
Vol 66 (01) ◽  
pp. 049-061 ◽  
Author(s):  
Björn Dahlbäck

SummaryThe protein C anticoagulant system provides important control of the blood coagulation cascade. The key protein is protein C, a vitamin K-dependent zymogen which is activated to a serine protease by the thrombin-thrombomodulin complex on endothelial cells. Activated protein C functions by degrading the phospholipid-bound coagulation factors Va and VIIIa. Protein S is a cofactor in these reactions. It is a vitamin K-dependent protein with multiple domains. From the N-terminal it contains a vitamin K-dependent domain, a thrombin-sensitive region, four EGF)epidermal growth factor (EGF)-like domains and a C-terminal region homologous to the androgen binding proteins. Three different types of post-translationally modified amino acid residues are found in protein S, 11 γ-carboxy glutamic acid residues in the vitamin K-dependent domain, a β-hydroxylated aspartic acid in the first EGF-like domain and a β-hydroxylated asparagine in each of the other three EGF-like domains. The EGF-like domains contain very high affinity calcium binding sites, and calcium plays a structural and stabilising role. The importance of the anticoagulant properties of protein S is illustrated by the high incidence of thrombo-embolic events in individuals with heterozygous deficiency. Anticoagulation may not be the sole function of protein S, since both in vivo and in vitro, it forms a high affinity non-covalent complex with one of the regulatory proteins in the complement system, the C4b-binding protein (C4BP). The complexed form of protein S has no APC cofactor function. C4BP is a high molecular weight multimeric protein with a unique octopus-like structure. It is composed of seven identical α-chains and one β-chain. The α-and β-chains are linked by disulphide bridges. The cDNA cloning of the β-chain showed the α- and β-chains to be homologous and of common evolutionary origin. Both subunits are composed of multiple 60 amino acid long repeats (short complement or consensus repeats, SCR) and their genes are located in close proximity on chromosome 1, band 1q32. Available experimental data suggest the β-chain to contain the single protein S binding site on C4BP, whereas each of the α-chains contains a binding site for the complement protein, C4b. As C4BP lacking the β-chain is unable to bind protein S, the β-chain is required for protein S binding, but not for the assembly of the α-chains during biosynthesis. Protein S has a high affinity for negatively charged phospholipid membranes, and is instrumental in binding C4BP to negatively charged phospholipid. This constitutes a novel mechanism for control of the complement system on phospholipid surfaces. Recent findings have shown circulating C4BP to be involved in yet another calcium-dependent protein-protein interaction with a protein known as the serum amyloid P-component (SAP). The binding sites on C4BP for protein S and SAP are independent. SAP, which is a normal constituent in plasma and in tissue, is a so-called pentraxin being composed of 5 non-covalently bound 25 kDa subunits. It is homologous to C reactive protein (CRP) but its function is not yet known. The specific high affinity interactions between protein S, C4BP and SAP suggest the regulation of blood coagulation and that of the complement system to be closely linked.


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