Outcome of older (≥70 years) APL patients frontline treated with or without arsenic trioxide-an International Collaborative Study

Data on outcome in older (≥70 years) patients with acute promyelocytic leukemia after treatment with arsenic trioxide (ATO) compared with standard chemotherapy (CTX) is scarce. We evaluated 433 patients (median age, 73.4 years) treated either with ATO+ all-trans retinoic acid (ATO/ATRA; n = 26), CTX/ATRA + ATO during consolidation (CTX/ATRA/ATO; n = 148), or with CTX/ATRA (n = 259). Median follow-up for overall survival (OS) was 4.8 years. Complete remissions (CR) were achieved in 92% with ATO/ATRA and 82% with CTX/ATRA; induction death rates were 8% and 18%, respectively. For analysis of postremission outcomes we combined the ATO/ATRA and CTX/ATRA/ATO groups (ATO/ATRA ± CTX). Cumulative incidence of relapse (CIR) was significantly lower after ATO/ATRA ± CTX compared with CTX/ATRA (P 10 × 10 9 /l) white blood cell (WBC) counts at diagnosis were associated with higher CIR (P < 0.001) compared with lower WBC in the CTX/ATRA group, but not in the ATO/ATRA ± CTX group (P = 0.48). ATO, when added to ATRA or CTX/ATRA is feasible and effective in elderly patients for remission induction and consolidation, particularly in patients with high WBC at diagnosis

Connexin-43 in the osteogenic BM niche regulates its cellular composition and the bidirectional traffic of hematopoietic stem cells and progenitors

Connexin-43 (Cx43), a gap junction protein involved in control of cell proliferation, differentiation and migration, has been suggested to have a role in hematopoiesis. Cx43 is highly expressed in osteoblasts and osteogenic progenitors (OB/P). To elucidate the biologic function of Cx43 in the hematopoietic microenvironment (HM) and its influence in hematopoietic stem cell (HSC) activity, we studied the hematopoietic function in an in vivo model of constitutive deficiency of Cx43 in OB/P. The deficiency of Cx43 in OB/P cells does not impair the steady state hematopoiesis, but disrupts the directional trafficking of HSC/progenitors (Ps) between the bone marrow (BM) and peripheral blood (PB). OB/P Cx43 is a crucial positive regulator of transstromal migration and homing of both HSCs and progenitors in an irradiated microenvironment. However, OB/P Cx43 deficiency in nonmyeloablated animals does not result in a homing defect but induces increased endosteal lodging and decreased mobilization of HSC/Ps associated with proliferation and expansion of Cxcl12-secreting mesenchymal/osteolineage cells in the BM HM in vivo. Cx43 controls the cellular content of the BM osteogenic microenvironment and is required for homing of HSC/Ps in myeloablated animal

Design and preclinical testing of an anti-CD41 CAR T cell for the treatment of acute megakaryoblastic leukaemia

Funding Information: Adrian Bogdan Tigu and Catalin Constantinescu contributed equally to the current manuscript. Catalin Constantinescu is funded by an internal grant of the Iuliu Hatieganu University – School of Doctoral Studies. David Kegyes is funded by an internal grant of the Iuliu Hatieganu University – School of Medicine. Mareike Peters is funded by a national grant of the Romanian Society for Bone Marrow Transplantation. Ciprian Tomuleasa is also supported by a grant awarded by the Romanian National Ministry of Research, Innovation and Digitalization: PN‐III‐P4‐ID‐PCE‐2020‐1118 within PNCDI IV, Projects for Exploratory Medicine; Projects for Exploratory Medicine—PCE 225/2021; as well as a national grant awarded to Young Research Teams (PN‐III‐PI‐1.1‐TE‐2019‐0271 –‘Supporting a team of young researchers to create an independent research program based on the use of Sleeping Beauty protocol f or the development of CAR T Cells – SEATTLE’). Diana Gulei, Diana Cenariu, Adrian Bogdan Tigu, Jon Thor Bergthorsson and Victor Greiff are supported by an international collaborative grant of the European Economic Space between Romania and Iceland 2021–2023: ‘Cooperation strategy for knowledge transfer, internationalization and curricula innovation in the field of research education at the 3rd level of study –AURORA.’ Publisher Copyright: © 2023 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.Acute megakaryoblastic leukaemia (AMkL) is a rare subtype of acute myeloid leukaemia (AML) representing 5% of all reported cases, and frequently diagnosed in children with Down syndrome. Patients diagnosed with AMkL have low overall survival and have poor outcome to treatment, thus novel therapies such as CAR T cell therapy could represent an alternative in treating AMkL. We investigated the effect of a new CAR T cell which targets CD41, a specific surface antigen for M7-AMkL, against an in vitro model for AMkL, DAMI Luc2 cell line. The performed flow cytometry evaluation highlighted a percentage of 93.8% CAR T cells eGFP-positive and a limited acute effect on lowering the target cell population. However, the interaction between effector and target (E:T) cells, at a low ratio, lowered the cell membrane integrity, and reduced the M7-AMkL cell population after 24 h of co-culture, while the cytotoxic effect was not significant in groups with higher E:T ratio. Our findings suggest that the anti-CD41 CAR T cells are efficient for a limited time spawn and the cytotoxic effect is visible in all experimental groups with low E:T ratio.Peer reviewe

Transforming growth factor β-mediated micromechanics modulates disease progression in primary myelofibrosis.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadPrimary myelofibrosis (PMF) is a Ph-negative myeloproliferative neoplasm (MPN), characterized by advanced bone marrow fibrosis and extramedullary haematopoiesis. The bone marrow fibrosis results from excessive proliferation of fibroblasts that are influenced by several cytokines in the microenvironment, of which transforming growth factor-β (TGF-β) is the most important. Micromechanics related to the niche has not yet been elucidated. In this study, we hypothesized that mechanical stress modulates TGF-β signalling leading to further activation and subsequent proliferation and invasion of bone marrow fibroblasts, thus showing the important role of micromechanics in the development and progression of PMF, both in the bone marrow and in extramedullary sites. Using three PMF-derived fibroblast cell lines and transforming growth factor-β receptor (TGFBR) 1 and 2 knock-down PMF-derived fibroblasts, we showed that mechanical stress does stimulate the collagen synthesis by the fibroblasts in patients with myelofibrosis, through the TGFBR1, which however seems to be activated through alternative pathways, other than TGFBR2. Keywords: TGF-β; fibroblast activation; invasion; micromechanics; myelofibrosis; proliferation.School of Doctoral Studies-Iuliu Hatieganu University Romanian Government Ion Chiricuta Oncology Institute Cluj Napoca international collaborative grant of the European Economic Space between Romania and Iceland 2020-2022 1

Outcome of older (≥70 years) APL patients frontline treated with or without arsenic trioxide—an International Collaborative Study

Leucèmia mieloide aguda; Genètica clínicaLeucemia mieloide aguda; Genética clínicaAcute myeloid leukaemia; Clinical geneticsData on outcome in older (≥70 years) patients with acute promyelocytic leukemia after treatment with arsenic trioxide (ATO) compared with standard chemotherapy (CTX) is scarce. We evaluated 433 patients (median age, 73.4 years) treated either with ATO+ all-trans retinoic acid (ATO/ATRA; n = 26), CTX/ATRA + ATO during consolidation (CTX/ATRA/ATO; n = 148), or with CTX/ATRA (n = 259). Median follow-up for overall survival (OS) was 4.8 years. Complete remissions (CR) were achieved in 92% with ATO/ATRA and 82% with CTX/ATRA; induction death rates were 8% and 18%, respectively. For analysis of postremission outcomes we combined the ATO/ATRA and CTX/ATRA/ATO groups (ATO/ATRA ± CTX). Cumulative incidence of relapse (CIR) was significantly lower after ATO/ATRA ± CTX compared with CTX/ATRA (P 10 × 109/l) white blood cell (WBC) counts at diagnosis were associated with higher CIR (P < 0.001) compared with lower WBC in the CTX/ATRA group, but not in the ATO/ATRA ± CTX group (P = 0.48). ATO, when added to ATRA or CTX/ATRA is feasible and effective in elderly patients for remission induction and consolidation, particularly in patients with high WBC at diagnosis.Open Access funding enabled and organized by Projekt DEAL

32Dcl3 cells with partial <i>Cebpa</i> knockdown retain capacity for nearly complete granulocytic maturation.

<p><b>A</b>) Parental 32Dcl3 cells, pools of 32Dcl3 cells stably transduced with the pLKO.1 vector (Vec) or <i>Cebpa</i> B9 or B11 shRNAs, or subclones of the B9 or B11 pools were subjected to Western blotting for C/EBPα and β-actin. <b>B</b>) Indicated 32Dcl3 lines were subjected to FACS analysis for GCSFR using biotin-G-CSF in the absence (heavy line) or presence (light line) of excess unbiotinylated G-CSF; x-axis is log scale (top). RNAs prepared from indicated 32Dcl3 lines cultured in IL-3 or after one or four days in G-CSF (G1, G4) were subjected to quantitative RT-PCR for <i>Mpo</i> (bottom, n = 3). <b>C</b>) Vector, B11-1, or B9-2 cells cultured in GCSF were subjected to Wright-Giemsa staining on the days of maximal differentiation, G6, G8, and G4 respectively (top row). Vector/GR, B11-1/GR, or B9-2/GR, G14, G14, and G6, respectively, were analyzed similarly (bottom row). <b>D</b>) Pools of vector, B11-1, or B9-2 lines transduced with pBabeNeo or pBabeNeo-GCSFR were subjected to FACS analysis for GCSFR (top). RNAs prepared from these lines in IL-3 or G-CSF were analyzed for <i>Mpo</i> expression (bottom, n = 3).</p

<i>Cebpa</i> knockdown reduces murine granulopoiesis relative to monopoiesis and increases immature blasts in liquid culture.

<p><b>A</b>) Transduced, puromycin selected marrow cells were placed in liquid culture with IL-3, IL-6, and SCF on D0 and viable cell counts were enumerated on days 0, 2, 3, 4, and 7. Representative data is shown. <b>B</b>) Cell cycle analysis was conducted using PI staining on D0 or D3. <b>C</b>) FACS analysis for Mac-1 and Gr-1 on D2. Arrows indicate immature, Mac-1⁻Gr-1⁻ cells (top). FACS analysis of Mac-1⁻Gr-1⁻ cells stained for Sca-1 and c-Kit (middle). FACS analysis of D2 cells for FcγR and CD34, gating on Lin⁻Sca-1⁻c-Kit⁺ progenitors (bottom). Representative data are shown. <b>D</b>) Total cellular RNAs collected on day 3 (D3) after lentiviral transduction with the pLKO.1 vector or with <i>Cebpa</i> shRNAs B9 or B11, puromycin selection, and transfer to IL-3, IL-6, and SCF were subjected to quantitative RT-PCR for indicated mRNAs (n = 3).</p