Patients with paroxysmal and persistent AF had a higher prevalence and number of areas of SCI per patient than controls and worse cognitive performance than subjects in sinus rhythm.
Transplantation of human acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) primary cells and cell lines in different strains of immunodeficient mice has led to preclinical models extensively used to investigate acute leukemia stem cells, biology and drug sensitivity. We studied the engraftment kinetics of AML and ALL cell lines and primary cells in 3 strains of NOD.CB17-Prkdc scid (NOD/scid, NS)-related mice (NOD.CgPrkdc scid B2m tm1Unc /J, abbreviated NOD/scid/b2 null, NSB; and NOD.Cg-Prkdc scid Il2rg tm1Wjll /SzJ, abbreviated NOD/scid/IL-2Rc null, NSG). The engraftment of human malignant cells was investigated by means of clinicopathological criteria, flow cytometry, PCR and immunohistochemistry. In NSG mice, we observed a significantly faster development of leukemia-related symptoms and a higher percentage of leukemia cells in the blood, in the marrow and in the spleen. The leukemia-related angiogenic switch (measured as the number of circulating endothelial cells and progenitors) was faster in NSG compared to NS and NSB mice. These models will be instrumental to studies on leukemia-initiating stem cells, leukemia biology, preclinical treatment studies, and to obtain patient-specific preclinical models to design and investigate patient-tailored therapies. ' 2008 Wiley-Liss, Inc.Key words: preclinical models; acute leukemia; circulating endothelial progenitors Different strains of immunodeficient mice have been studied to generate models of human acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) and to investigate AML and ALL stem/initiating cells, biology and drug sensitivity. 1-10 The NOD.CB17-Prkdc scid (NOD/scid, NS) strain has been the most widely used in these studies. However, only a limited amount of AML patient samples exhibit detectable engraftment in this mouse model. Various strategies designed to enhance leukemia cell engraftment in NS mice, including injection of cytokines and cotransplantation of accessory cells, did not significantly improve these results. 11-14 Two NS-related strains, namely NOD.CgPrkdc scid B2m tm1Unc /J, abbreviated NOD/scid/b2 null (NSB; 5,6) and NOD.Cg-Prkdc scid Il2rg tm1Wjll /SzJ, abbreviated NOD/scid /IL2Rg null (NSG; 7,8) mice, have been recently investigated as models to generate a human hematopoiesis in a murine host. Compared to NS, absence of b2 microglobulin in NSB mice leads to a lack of MHC class I expression and decreased NK-cell function. 1,5,6 Compared to NS, the IL-2Rg-chain deficiency in NSG mice impairs the signaling through multiple cytokine receptors blocking NK development and results in additional defects in innate immunity. 1,8 NS and NSB mice develop early thymic lymphomas that in NSB mice determine a markedly shortened life span. 1,8 Previous reports have compared human engraftment of cord blood CD34-positive cells in NS and NSB mice 14 or NS and NSG mice, 8 but not as hosts for leukemia engraftment. Hogge's group presented data suggesting improved engraftment of AML cells in NSB compared to NS mice. 6 However, n...
Purpose: Antigenic overlap among circulating endothelial cells (CEC) and progenitors (CEP), platelets, and other blood cells led to the need to develop a reliable standardized method for CEC and CEP quantification. These cells are emerging as promising preclinical/clinical tools to define optimal biological doses of antiangiogenic therapies and to help stratify patients in clinical trials. Experimental Design: We report the experimental validation of a novel flow cytometry method that precisely dissects CEC/CEP from platelets and other cell populations and provides information about CEC/CEP viability.+ CECs, investigated by electron microscopy, were found to be bona fide endothelial cells by the presence of Weibel-Palade bodies. More than 75% of the circulating mRNAs of the endothelial-specific gene,VE-cadherin, found in the blood were present in the sorted population. CECs were 140 F 171/mL in healthy subjects (n = 37) and 951 F1,876/mL in cancer patients (n = 78; P < 0.0001). The fraction of apoptotic/necrotic CECs was 77 F 14% in healthy subjects and 43 F 23% in cancer patients (P < 0.0001). CEPs were 181 F 167/mL in healthy donors and 429 F 507/mL in patients (P = 0.00019). Coefficients of variation were 4 F 4% (intrareader), 17 F 4% (interreader), and 17 F 7% (variability over 0-72 h), respectively. Parallel samples were frozen by a standardized protocol. After thawing, coefficients of variation were 12 F 8% (intrareader), 16 F 10% (interreader), and 26 F 16% (variability over 0-14 days of frozen storage), respectively. Conclusions: This procedure enumerates a truly endothelial cell population with limited intrareader and interreader variability. It appears possible to freeze samples for large-scale CEC enumeration during clinical trials.This approach could be enlarged to investigate other angiogenic cell populations as well.
Background Medical treatment in Cushing’s disease (CD) is limited due to poor understanding of its pathogenesis. Pathogenic variants of ubiquitin specific peptidase 8 (USP8) have been confirmed as causative in around half of corticotroph tumors. We aimed to further characterize the molecular landscape of those CD tumors lacking USP8 mutations in a large cohort of patients. Methods Exome sequencing was performed on 18 paired tumor–blood samples with wild-type USP8 status. Candidate gene variants were screened by Sanger sequencing in 175 additional samples. The most frequent variant was characterized by further functional in vitro assays. Results Recurrent somatic hotspot mutations in another deubiquitinase, USP48, were found in 10.3% of analyzed samples. Several possibly damaging variants were found in TP53 in 6 of 18 samples. USP48 variants were associated with smaller tumors and trended toward higher frequency in female patients. They also changed the structural conformation of USP48 and increased its catalytic activity toward its physiological substrates histone 2A and zinc finger protein Gli1, as well as enhanced the stimulatory effect of corticotropin releasing hormone (CRH) on pro-opiomelanocortin production and adrenocorticotropic hormone secretion. Conclusions USP48 pathogenic variants are relatively frequent in USP8 wild-type tumors and enhance CRH-induced hormone production in a manner coherent with sonic hedgehog activation. In addition, TP53 pathogenic variants may be more frequent in larger CD tumors than previously reported.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.