bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vascular Endothelial Growth Factor Contributes to Adverse Patient Outcome in Acute Myeloid Leukemia by Promoting Cell Growth and Survival and by Reducing the Sensitivities of Leukemic Cells to Drug-Induced Apoptosis.
Authors: Brunhoff Cecilia , Ekblad Jenny , Persson Jenny Liao 
Published: April 2020

Abstract
Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that contributes to the regulation of hematopoietic stem cell development, extracellular matrix modelling and inflammatory cytokine generation. To study the potential role of VEGF in proliferation and apoptosis in acute myeloid leukemia, we evaluated the VEGF protein expression and its association with disease characteristics and patient outcome in 42 patients with acute myeloid leukemia (AML). In contrast to its weak expression in myeloid progenitors in normal bone marrows, high levels of VEGF expression was detected in 22 of the AML patients. Interestingly, VEGF expression significantly correlated with the expression of several major cell cycle regulatory proteins including cyclin A1, cyclin A2, cyclin E, CDK2 and p27. Log-rank test stratified by levels of VEGF expression revealed a clear trend with worse overall survival for patients with high levels of VEGF compared to those with low levels. Treatment of U-937 cells with recombinant VEGF protein resulted in an increased rate of proliferation. This suggested that VEGF may promote cell growth by mediating the cell cycle regulatory pathways. We further demonstrated that induced expression of VEGF promoted survival of leukemic cells and protected the cells from ATRA-induced apoptosis. Taken together, our studies demonstrated that increased expression of VEGF in AML patients was associated with worse patient outcome. Elevated levels of VEGF may contribute to the adverse outcome by promoting cell growth and survival of leukemic cells and reducing the sensitivity of leukemic cells to drug-induced apoptosis in AML patients.
Poly-Glutamine Induces Bax-Mediated Cell Death by Dissociating Ku70 from Bax through Ku70-Acetylation.
Authors: Gama Vivian , Yoshida Tomoyuki , Cohen Haim , Sinclair David , Yokota Takanori , Distelhorst Clark , Matsuyama Shigemi 
Published: April 2020

Abstract
Poly-glutamine (PolyQ) diseases (e.g. Huntington’s disease and Machado-Joseph disease) are caused by the amplification of CAG repeats in the genes of proteins normally expressed in the cell. PolyQ induces caspase-independent cell death associated with vacuolization in the cytoplasm that is distinct from the previously known cell death types such as apoptosis and necrosis. PolyQ-induced cell death is considered a new type of cell death and the elucidation of its mechanism is being awaited. At present, there is no effective treatment to rescue cells from polyQ’s toxicity. Previously, we developed cell permeable cytoprotective peptides designed form Bax-inhibiting domain of Ku70, and these peptides were named Bax Inhibiting Peptides (BIPs). We found that BIP (50 – 200 uM range) blocked polyQ-induced cell death in human epithelial kidney (HEK) 293T cells and human neuroblastoma cell line (Neuro2). PolyQ was expressed by plasmid transfection and cell death was detected by trypan blue exclusion and the release of Lactose Dehydrogenease (LDH) from dead cells into the medium. BIP almost completely suppressed polyQ-induced cell death and vacuolization while caspase-inhibitor (z-VAD-fmk) did not. In Bax-deficient human prostate cancer cell (Du145), polyQ did not induce cell death, but the expression of sub-lethal level of Bax restored the toxicity of polyQ in Du145. Bax changes its conformation when it is activated to mediate cell death and the “active” Bax can be detected by a specific monoclonal antibody (6A7 antibody). By immunohistochemistry Bax activation was confirmed in the neurons of human patients suffering from PolyQ disease as well as in the neurons of a transgenic mouse model of the disease. Previously we found that Ku70 binds and inhibits Bax activation, and that the acetylation of Ku70 releases Bax from Ku70. We found that polyQ binds Ku70 and a Histone Acetyl-Transferase (Creb Binding Protein-CBP), and thus polyQ mediates Ku70 acetylation in the cells. We confirmed that Ku70 overexpression protects cells from polyQ expression whereas Ku70 mutants mimicking acetylated Ku70 did not. Based on these in vivo and in vitro studies, we propose that Bax plays a key role in polyQ-induced cell death and that BIP and Ku70 may be utilized to rescue cells from this kind of death in patients suffering from polyQ diseases.
Outcomes after HLA-Identical Sibling Allogeneic Peripheral Blood Stem Cell Transplantation Using Reduced Intensity Conditioning Compared to Autologous Peripheral Blood Stem Cell Transplantation for Elderly Patients with De Novo Acute Myeloid Leukemia.
Authors: Herr Andree-Laure , Labopin Myriam , Blaise Didier , Potter Mike , Ferrara Felicetto , Carreras Enric , Arcese William , Nagler Arnon , Gorin Norbert C. , Frassoni Francesco , Rocha Vanderson 
Published: April 2020

Abstract
Results of allogeneic hematopoietic stem cell transplantation (HSCT) in elderly patients are associated to high TRM mainly due to toxic effects of myeloablative preparative regimen allogeneic and GVHD. Therefore, chemotherapy or autologous (auto) HSCT are often treatment alternatives. Recently, allogeneic peripheral blood SCT (PBSCT) with reduced-intensity conditioning (RIC) has emerged as an alternative to decrease TRM and to add a GVL effect. We have conducted a registry-based retrospective risk-adjusted comparative analysis of outcomes of 204 RIC-PBSCT to those of 954 auto-PBSCT in adult patients aged 50 years or older with de novo AML. Transplants were performed from 1997 until 2003 and reported to the EBMT. Median age was similar in both groups (58 y in RIC and 57y auto PBST), however RIC patients were transplanted more recently, had more advanced disease at time of transplant and poorer cytogenetics compared to the auto-PSCT group (p&lt;0.05). The majority of conditioning regimens used in the RIC group was fludarabine-based associated to low dose TBI or Busulfan (&lt;8mg/kg). Median follow-up was 13 months in both groups. Median time to engraftment was 16 days in the RIC group and 12 days in the auto group (p &lt;0.0001). Unadjusted one-year probability of TRM was 15 ±3% in RIC and 8±1% in auto (p=0.002) and one-year probability of relapse were 34 ±3% in the RIC group versus 40 ±2% in the auto group (p = 0.31). However after adjustment, multivariate analysis showed a lower risk for relapse (RR 0.75, p = 0.04) but a trend for a higher TRM (RR 1.57, p = 0.07) for RIC patients. Major causes of non leukemic death in the RIC group were infections and graft-versus-host disease; and in the auto group, infections. Unadjusted one-year probabilities of leukemia-free survival (LFS) and overall survival (OS) were not statistically different in both groups: LFS of 50±4% in the RIC group versus 52±2% in the auto group (p = 0.31), and OS of 62±4% versus 66±2% (p = 0.23), respectively. In a multivariate analysis, OS and LFS were not statistically different for both groups. In the subgroup analysis, unadjusted one-year probability of LFS was 62±8% for patients in 2nd complete remission receiving RIC transplants compared to 43±6% (p=0.02). Conclusion: Allogeneic HLA identical RIC PBSCT is an effective treatment option for older patients with AML, with acceptable overall survival and decreased relapse incidence compared to autologous PBSCT. These results suggest that RIC PBSCT are feasible in a high risk population and should be evaluated in prospective trials in elderly AML.
Properties of MSC Derived Stromal Cell Lines Developed from Bone Marrow of TNF Knockout Mice.
Authors: Nifontova Irina N. , Rosov Fedor N. , Beliavsky Alexander V. , Drize Nina J. 
Published: April 2020

Abstract
Mesenchymal stem cells (MSC) forming adherent stromal cell lines have been revealed in suspension fraction (SF) of 70+ weeks old long-term bone marrow culture (LTBMC) of TNF knockout mice.
The proportion of CD45+ cells in such old cultures decreased significantly while cellularity of SF increased, accompanied by the first successful generation of cell lines. More than 100 cell lines were established.
Almost all cell lines were Sca1 positive, expressed SDF1, had fibroblast-like morphology and expressed collagens type II and IV. Most of cell lines could maintain hematopoiesis (CFU-S, CFU-GM and CAFC production) for 10 weeks. Some of the cell lines were able to maintain growth without differentiation of murine ES cells and some expressed LIF or LIF-receptor, VEGF and FGF1. All cell lines produced hematopoietic growth factors - their supernatants stimulated growth of CFU-GM in semisolid media. The expression of SCF was revealed in all cell lines tested for growth factors production.
Quantitative RT-PCR analysis revealed that the expression of hematopoietic growth factors - M-CSF, G-CSF and TPO increased sometimes up to 6 times in comparison with the expression of these factors in adherent cell layer (ACL) of LTBMC. The expression of N-cadherin - one of the main regulators of hematopoietic stem cells (HSC) in niche - increased 7–32 fold in 7 tested cell lines regarding the expression of this RNA in ACL of LTBMC. Whereas the expression level of N-cadherin was lower in wild type bone marrow, NIH3T3 fibroblasts and MS5 cells, maintaining the hematopoiesis and CAFC growth, showed the expression on the higher level than in ACL. The expression of ICAM 1, the molecule also regulating HSC, was reduced in all cell lines. The expression level of genes participating in activating of hematopoietic stem cells in niche such as Jagged, Dll 1 and Ang1 more than halved in 5 out of 7 tested lines. The production of Wnt 5a RNA fluctuated from 0,5 to 12 fold and did not correlate with any other changes in gene expression and the ability of cell lines to maintain hematopoiesis. The level of Ihh, Shh was downregulated in cell lines.
The cell line 26dD3 developed in the media containing dexamethasone demonstrated 70 fold increased expression of Kirre - gene supporting HSC but there was no difference in maintaining hematopoiesis and ES cells. High expression of human homolog of this gene (NEPH2) was known to be detected in brain only. At the same time this cell line expressed tubulin b3. These data support a model of lineage specification in which unilineage commitment is prefaced by a “promiscuous” phase of multilineage locus activation. Thus the developed stromal cell lines are not terminally differentiated and use different pathways to maintain hematopoiesis. The TNF deficiency leads to dramatic alterations in regulation of MSC. Mechanisms of this regulation should be scrutinized.
Regeneration of Hematopoietic Microenvironment (Bone Marrow) Using Adipose-Derived Stem Cells - The 2nd Report.
Authors: Ogawa Rei , Fujimura Juri , Mizuno Hiroshi , Hyakusoku Hiko , Shimada Takashi 
Published: April 2020

Abstract
Backgrounds: We have reported bone marrow regeneration using adipose-derived stem cells (ASCs) since 2003. In our study using mice, we showed that not only bone matrix but also bone marrow could be regenerated subcutaneously in vivo. Transplanted ASCs proliferated and differentiated into osteoblasts in micropores on the surface of scaffolds made of hydroxyapatites (HA). We have not yet obtained incontrovertible proof that the ASCs differentiated into hematopoietic cells. However, we could regenerate a subcutaneous microenvironment in which hematopoietic cells survived, which may lead to new treatments for fibrotic bone marrow diseases, such as idiopathic myelofibrosis and osteopetrosis.
Purposes: In this report, we examined the optimal shapes of scaffolds for bone and bone marrow regeneration using ASCs.
Methods: Taking advantage of homogeneously marked cells from green fluorescent protein (GFP) transgenic mice, ASCs were isolated from the inguinal fat pads of GFP transgenic mice. ASCs were cultured in vitro and after three passages were seeded into the small pores of scaffolds of various shapes made of HA. The ASC-containing scaffolds were then subsequently implanted into immunocompetent mice subcutaneously. Two months later, the scaffolds were extirpated for histological, immunohistochemical and flow cytometry analyses.
Results: Histological examination showed that the pores were filled with bone matrix and that the bone marrow was composed of adipocytes, hematopoietic cells, and vasculatures. Bone marrow regeneration on small, thin scaffolds of high porosity was better than on other scaffolds. Immunohistochemical analysis confirmed that the GFP+ ASCs that had differentiated into osteoblasts were composed of bone matrix. Flow cytometry analyses showed that the bone marrow was composed of blood cells, including populations of monocytes, lymphocytes and granulocytes.
Conclusions: Bone marrow engineering has great potential for hematopoietic disease therapy. The regeneration of the hematopoietic system using ASCs might be useful in the future for treating hematopoietic stem cell diseases such as leukemia as well as fibrotic bone marrow diseases. We plan to continue looking for suitable scaffolds and methods for bone and bone marrow regeneration using ASCs.
A Novel Method of Isolation of Mesenchymal Stem Cells from Human Umbilical Cord Tisssues.
Authors: Lu Lulu , Liu Yong-jun , Xu Zhen-shu , Fan Cun-gang , Wang Han , Gong Wei , Han Zhi-bo , Lu Yong-xin , Liu Delong , Chen Zhi-zhe , Han Zhong-chao 
Published: April 2020

Abstract
Mesenchymal stem cells (MSCs) have been isolated from venous endothelia and subendothelia of the human umbilical cord using a tedious procedure. We established a simple method to isolate abundant MSCs from human umbilical cord tissues (UC). 36 full-term umbilical cords were obtained. MSCs were isolated after enzyme digestion of minced cord fragments. The mean nucleated cells isolated from UC was 1.13±0.37×106/cm UC. A total of 1×10e10 MSCs was obtained after several passages over 4 weeks. CFU-F frequency is 1:1609. The population doubling time was approximately 28.02±10.53 h in passage 2 cells. The MSC cells were positive for CD13, CD29, CD44, SH-2, SH-3, CD166 and HLA class I (A, B, C), but were negative for CD34, CD38, CD45, CD31 and HLA-DR. More than 80% cells were in G0-G1 phase, whereas a small population of cells was engaged in proliferation (S+G2+M=9.16%). Under specified culture conditions, the MSC cells differentiated into adipocytes, osteoblasts and neural cells. The MSCs were also found to express cytokines of SCF, LIF, M-CSF, Flt3-ligand, IL-6, GM-CSF, G-CSF, VEGF, and SDF-1. When co-cultured with CD34+ cells from UC blood, the UC-derived MSCs were able to support the hematopoiesis of long-term culture-initiating cells. These findings suggested that abundant MSCs can be isolated simply and effectively from the whole cord tissue. Umbilical cords may be an attractive source of MSCs for tissue engineering, cord blood expansion and cord blood transplantation.
Mesenchymal Stem Cells from Bone Marrow of Children with Malignant and Non Malignant Hematological Disorders Are Not Quantitatively and Qualitatively Affected.
Authors: Dimitriou Helen , Linardakis Emmanouela , Martimianaki Georgia , Stiakaki Eftichia , Fillipidi Anthi , Kaparou Maria , Kalmanti Maria 
Published: April 2020

Abstract
Mesenchymal Stem Cells (MSCs) are multipotent progenitor cells within the bone marrow (BM) capable of differentiating into various tissue specific cells including adipocytes (A), osteoblasts (O), chondrocytes (C), myoblasts, hepatocytes and possibly neuronal tissue. MSCs form an integral part of the BM stroma, have immunomodulatory functions and play an important role in the support of hematopoeisis. Their multipotentiality and ease of ex vivo expansion has raised great interest in the clinical use of MSCs for tissue repair and gene therapy. In order to evaluate if malignant and non malignant hematological diseases quantitatively and qualitatively affect BM derived MSCs, bone marrow from children with Acute Lymphoblastic Leukemia (ALL diagnosis n=9, different stages of treatment n=14, end of therapy n=9), Idiopathic Thrombocytopenic Purpura (ITP, n=12), autoimmune neutropenia (n= 9) and control patients (solid tumors without bone marrow involvement, n=19) was harvested and the mononuclear cell (MNC) fraction isolated. MSCs were expanded in aMEM supplemented with 10% selected FCS, characterized and compared in terms of their phenotypic characteristics, clonogenicity and ability to differentiate into A, O and C lineages. MNCs at day 0 of culture expressed high levels of CD34, CD45, CD29 and CD44, and very low levels of CD14, CD105 and CD90. Expression of hematopoietic markers (CD34, CD45 and CD14) on cells at passage 1 (P1) and thereafter progressively diminished while expression of CD29, CD44, CD90 and CD105 increased approaching 100%. High clonogenicity was observed in all samples at all passages as shown by the presence of CFU-F colonies (&gt;50 cells) with the exception of ALL samples at diagnosis which showed impaired proliferation and clonogenicity that returned to normal at the following stages of treatment till the end of therapy. At P2 or P3, MSCs were differentiated towards the A, O, and C lineages by using specific induction media. Differentiation was assessed by histochemistry (Oil red O for A, von Kossa and Alkaline phosphatase (ALP) for O and Alcian Blue for C) and RT-PCR (LPL and aP2 for A, osteoprotegerin, osteocalcin and ALP for O, aggrecan and Col II for C). P2 or P3 MSCs from all groups exhibited bi- or tri-lineage differentiation. These results indicate that blood diseases of childhood do not affect the characteristics of MSCs and therefore could have clinical uses particularly in hematopoietic reconstitution following allotransplantation.
A Comparison of Mesenchymal Cells from Different Tissues To Suppress T-Cell Activation.
Authors: Keyser Kirsten A. , Beagles Karen E. , Kiem Hans-Peter 
Published: April 2020

Abstract
Graft failure and graft-versus-host-disease (GvHD) remain significant complications of allogeneic stem cell transplantations. To reduce the risk of GvHD, patients often receive a graft that has been depleted of T-cells, which in turn increase the risk of graft failure. Studies have suggested that co-transplantation of ex vivo expanded marrow derived mesenchymal stem cells (MSCs) with allogeneic hematopoietic stem cells (HSC) reduces the risk of GvHD and graft rejection. Additionally, it has been shown that infusion of expanded marrow derived MSCs improves ongoing acute GvHD and facilitates engraftment across MHC-barriers. The effect of MSCs is thought to be due to their ability to suppress T-cell activation. Here we wished to examine whether inhibition of T-cells could be enhanced by MSCs from different tissues. We were particularly interested in MSCs derived from adipose tissue, because of its abundance and accessibility, which is especially important for repeat applications. We investigated and compared the immunosuppressive potential of MSCs derived from multiple mesenchymal tissues of different origins, such as adipose tissue, muscle tissue, omentum, and bone. Cells from the different tissues were enriched for MSCs and cultured and expanded for two to three weeks to deplete hematopoietic cells. MSCs from all tissues differentiated into multiple lineages and stained positive using antibodies against common MSC markers (CD29, CD44, CD105, CD106) and negative for hematopoietic markers (CD3, CD14, CD34, CD45). Mixed lymphocyte reactions (MLRs) using either a mitogen (Concanavalin A) or allogeneic T-cells as inducers of T-cell activation were performed in the presence or absence of MSCs from the different tissues. Mitogen-induced T-cell activation, as well as allogeneic T-cell responses were significantly reduced in MLRs with MSCs compared to MLRs without MSCs. The most pronounced effects were observed with MSCs from muscle tissue (90% reduction) in the mitogen-induced MLR and with MSCs from adipose tissue (85% reduction) in the allogeneic MLRs. These results suggest that MSCs from adipose tissue, which is easily optained and abundantly available, could be used to modulate GvHD and facilitate engraftment across MHC barriers. In conclusion our data demonstrate that MSCs from multiple tissues efficiently reduce T-cell activation and suggest that MSCs from adipose tissue can serve as an alternative source for MSCs to modulate GvHD or facilitate engraftment across MHC barriers. In vivo studies to test the effects on GvHD are currently under way.
Mesenchymal Cancer Cells Can Arise from Ex Vivo Modified Mesenchymal Stem Cells.
Authors: Tolar Jakub , Osborn Mark J. , Panoskaltsis-Mortari Angela , McElmurry Ron T. , Bell Scott , Xia Lily , Riddle Megan , Schroeder Tania M. , Westendorf Jennifer J. , McIvor R. Scott , Oseth LeAnn , Hirsch Betsy , Yant Stephen R. , Kay Mark A. , Peister Alexandra , Prockop Darwin J. , Blazar Bruce R. 
Published: April 2020

Abstract
Mesenchymal stem cells (MSCs) can differentiate into non-hematopoietic cell types, including adipocytes, chondrocytes and osteocytes. MSCs have been isolated from multiple species, including humans, and multiple organs, including bone marrow, adipose tissue and umbilical cord blood. The beneficial effects of MSCs are being tested clinically in attempts to: improve hematopoietic engraftment, to treat osteogenesis imperfecta, graft-versus-host disease and autoimmune diseases, and as antitumor agents to deliver therapy for malignancies. Phase I clinical studies have not been associated with toxicities. We aimed to investigate the capacity of MSCs to aid in tissue healing after radiation induced injury in irradiated bone marrow transplant (BMT) recipients. To study the biodistribution of MSCs, we labeled adult murine C57BL/6 MSCs with firefly luciferase and DsRed2 fluorescent protein using non-viral Sleeping Beauty transposons, and co-infused them with allogeneic bone marrow into irradiated reipients. Using in vivo whole body bioluminenscent imaging luciferase signals were shown to be increased between weeks 3 and 12 indicating expansion of MSCs. Unexpectedly, some mice (N=8/17) with the highest luciferase signals died and all surviving mice (N=9/17) developed foci of ectopic ossification in lungs. Two of mice also developed osteosarcomas in their extremities. This prompted us to characterize the transformed MSCs that originated from the donor MSCs. The transformed cells were aneuploid, lost their capacity to differentiate into mesenchyme-derived adipocytes and chondrocytes, and histologically identified as osteosarcomas. In addition, infusion of tumor cells resulted in malignant lesions in secondary recipients. Mapping of transposition sites in the genome and karyotype analysis indicated that the critical transformation event(s) occurred before infusion of the MSCs. Even though we have not encountered a transformation event in &gt;100 mice infused with MSC manipulated with transposons, we speculated that mutation by transposition was the inciting event. None of the identifiable transposition events occurred in a known proto-oncogene or tumor suppressor gene. This does not discount the possibility of insertional mutagenesis as the genomic lesion may have occurred on the chromosome which was subsequently disrupted or lost. Alternatively, genomic instability could have been a result of spontaneous unrepaired chromosomal lesion(s) that preceded the transposon insertion and resulted in osteosarcoma. These findings provide evidence of evolution of MSCs with osteogenic capacity into osteosarcoma in vivo and are clinically relevant as they document the potential of ex vivo manipulated MSCs for transformation into malignant disease.