bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oral Treatment with PBI-1402 Increases Hemoglobin Level and Red Blood Cell Count: A Novel Approach to Treating Chemotherapy-Induced Anemia.
Authors: Gagnon Lyne , Barabe Jean , Penney Christopher , Roy Denis-Claude , Kovcin Vladimir , Bosnjak Snezana , Laurin Pierre 
Published: April 2020

Abstract
Background: PBI-1402 is a novel orally active low molecular weight synthetic compound with erythropoiesis stimulating activity. Furthermore, a clinical phase I study showed that PBI-1402 induced a significant increase (100%, p &lt; 0.0001, compared to placebo) of relative and absolute reticulocyte count in healthy volunteers after 21 days of oral treatment and was devoid of significant side effects.
Outcomes: The objectives of this clinical phase Ib/II trial were to study the safety and tolerability of PBI-1402 and to assess its biological efficacy on hemoglobin (Hb) level and red blood cell (RBC) count in patients with Chemotherapy-Induced Anemia (CIA).
Methods: An open label phase Ib/II trial, monitored by a US CRO (Pharm-Olam International), was conducted in patients developing anemia after chemotherapy treatment. Three cohorts of 6 CIA patients received 8 weeks of treatment with PBI-1402 once a day, at different doses, and were monitored every two weeks for safety, tolerability, Hb level, RBC count and blood chemistry. Patients remained on their chemotherapy during PBI-1402 treatment.
Results: To date, 12 CIA patients have completed their PBI-1402 treatment. 83% of patients demonstrated a significant increase in RBC (p = 0.015) and 66% in Hb (p = 0.038). Among the responders, the mean Hb increase was 1.1 g/dL (p = 0.0007) from a baseline Hb value of 9.8 g/dL. No patient required a blood transfusion and only one patient had an Hb content below 9 g/dL (8.9 g/dL). PBI-1402 was well tolerated and no significant side effects were observed.
Conclusion: PBI-1402, via a mechanism of action distinct from erythropoietin, induced sufficient erythropoiesis to raise the RBC level and Hb in CIA patients. In addition, PBI-1402 is safe and well tolerated. PBI-1402 offers the potential for a novel therapy of the anemia of CIA.
A Unified Mechanism of Tyrosine Kinase Regulation by the Gatekeeper Residue.
Authors: Azam Mohammad , Seeliger Markus , Gray Nathanael S. , Kuriyan John , Daley George Q. 
Published: April 2020

Abstract
Protein kinase inhibitors achieve binding specificity through contact with a hydrophobic pocket within the ATP-binding cleft. Access to the pocket is dictated by an amino acid residue dubbed the “gatekeeper”, which is threonine in many kinases. Drug resistance is often due to substitution of the gatekeeper threonine with a bulkier amino acid residue that sterically hinders the binding of some drugs. Here we show that substituting a bulky hydrophobic residue in place of threonine in the native cellular forms of c-ABL, c-SRC, PDGFRA, PDGFRB, and EGFR activates kinase activity and promotes malignant transformation of BaF3 cells. Structural modelling and crystallographic analysis reveal that a network of hydrophobic interactions characteristic of the active kinase conformation is stabilized by the gatekeeper substitution. In the inactive kinase conformation, this hydrophobic interactions are dismantled. A small molecule inhibitor that maximizes complementarity with the dismantled spine (Compound #14) inhibits the gatekeeper mutation of BCR/ABL (T315I). These results demonstrate that mutation of the gatekeeper threonine is a common mechanism of activation for tyrosine kinases, and provide structural insights to guide the development of novel inhibitors.
Expression of G-CSF Receptor during Embryonic Development in a Csf3r-Cre Knock-In Mouse Model.
Authors: Touw Ivo P. , Valkhof Marijke , Erkeland Stefan J. , Meijers Karel , Danen-van Oorschot Astrid 
Published: April 2020

Abstract
G-CSF is the major regulator of neutrophil development and controls the proliferation, differentiation and survival of myeloid progenitors in both steady state and “emergency” granulopoiesis. More recently however, novel activities of the G-CSF/G-CSF receptor (CSF3R) axis have been suggested, especially after severe forms of tissue damage. For instance, upon myocardial infarction, G-CSF was shown to protect cardiomyocytes from apoptosis, reducing the extent of myocardial damage. Likewise, in ischemic stroke models, G-CSF treatment reduced infarct volumes by promoting neuronal survival and differentiation of neural stem cells in the brain. Finally, G-CSF has been suggested to promote hepatic regeneration after severe liver damage by directly stimulating the proliferation of oval cells. To study whether and to what extent CSF3R expression in damaged tissues reflects reactivation of a normal development program, we generated a csf3r-Cre knock-in model. To this end, the csf3r locus was targeted with a construct containing the cre gene and a puromycin selection cassette flanked by a 2.7 kb fragment of the csf3r 5′UTR and a 4 kb fragment directly downstream of the initiation codon of csf3r. Correct insertion of the cre gene was confirmed by Southern blotting and sequence analysis and subsequent crossing with FLP deleter mice resulted in successful germ line transmission and deletion of the puromycin cassette. These mice were crossed with the R26R LacZ reporter mouse and β-galactosidase (β-gal) activity was examined by FACS and histochemical analysis. At E9.5, no β-gal activity was detected, indicating that csf3r is not expressed at that stage of development. In contrast, in E12.5 embryos, β-gal staining was observed in fetal liver, heart, kidney, brain and intestine. Analysis of adult tissues showed that cardiomyocytes were β-gal positive in a mosaic pattern. A similar mosaicism was observed in liver, kidney and the intestines. In liver both hepatocytes and vascular endothelial cells stained positive, whereas in the kidney β-gal staining was detected in vascular endothelium, glomeruli and afferent and efferent vessels. In ileum and colon, β-gal activity was mainly seen in the stem and progenitor cell-containing crypts and the developing progeny migrating upwards along the villus. In bone marrow, high levels (&gt;40%) of β-gal activity were detected in Gr1+ and CD11b+ myeloid cells, CD19+ (B) and CD3ε+ (T) lymphoid cells, NK cells and CD11c+ dendritic cells, indicating that G-CSFR was expressed in a common progenitor of these cell types. In agreement with this, β-gal activity was also detected in the primitive LSK population. In conclusion, our data indicate that CSF3R is expressed in both hematopoietic and multiple non-hematopoietic organs from embryonic development stage E12.5 onward. This may have important ramifications for a more wide-spread application of G-CSF in tissue regeneration.
Cobblestone Area-Forming Cell (CAFC) Content of Cord Blood Does Not Predict Engraftment in Double Cord Blood Transplantation.
Authors: Robinson Simon N. , de Lima Marcos , Yang Hong , Decker William K. , Xing Dongxia , Steiner David , Ng Jingjing , Thomas Michael W. , Champlin Richard E. , Hosing Chitra M. , Simmons Paul J. , Brouard Nathalie , Kidd Shannon , Cooper Laurence , Zweidler-McKay Patrick A. , Shpall Elizabeth J. 
Published: April 2020

Abstract
INTRODUCTION: Delayed engraftment remains a serious problem following cord blood (CB) transplantation. It may be due, at least in part, to the limited dose of CB hematopoietic stem and progenitor cells (HSPC) transplanted. Limitations associated with HSPC dose may be reduced by the transplantation of 2 CB units. In an accompanying abstract, de Lima et al. report in detail on an ongoing MDACC randomized study in which patients received double CB units as either 2 unmanipulated units (2×UN), or 1 unmanipulated and 1 ex vivo expanded CB unit (UN+EX). This study has revealed that one CB unit ultimately predominates as the source of long-term, sustained hematopoiesis. We hypothesized that the number of primitive HSPC in the CB unit might ultimately predict which CB unit would ultimately prevail. The in vitro cobblestone area-forming cell (CAFC) assay was used to provide a measure of primitive components of the CB HSPC in each unit. A photomicrograph of a typical cobblestone area (CA) derived from a single CB-derived CAFC is shown. (Figure) CA persisting in in vitro culture for ≥6 weeks (derived from CAFCwk6) represent relatively primitive HSPC and their numbers may provide a qualitative profile for CB units. We hypothesized that of the two CB units transplanted, the one with the greater number of CAFCwk6 would ultimately persist long-term in the patient.
METHODS: Clinical samples of 2×UN or UN+EX CB cells were plated in the in vitro CAFC assay.1 The frequency of CAFCwk6 was estimated and total CAFCwk6 numbers transplanted for each CB unit calculated. CAFCwk6 data for each CB unit and engraftment data from patients were analyzed to determine whether the number of CAFCwk6 transplanted was predictive of which CB unit would ultimately be responsible for long-term, sustained engraftment.
RESULTS: Preliminary data was accrued from 10 patients.(Table) Six patients received 2×UN and 4 patients received UN+EX (EX indicated by #). CAFCwk6 content at transplant was predictive of which CB unit would ultimately be responsible for long-term, sustained engraftment in only 6 of the 10 cases (60%).
CONCLUSION: CAFCwk6 represent a relatively primitive component of the HSPC compartment, however, these data suggest that CAFCwk6 numbers, although possibly a qualitative measure, are not a predictor of long-term sustained engraftment.
Figure Figure
Mir-135a Expression Is Associated with Relapse in Hodgkin Lymphoma.
Authors: Navarro Alfons , Gaya Anna , Pons Aina , Urbano-Ispizua Alvaro , Martinez Antonio , Gel Bernat , Balagué Olga , Granell Miquel , Artells Rosa , Abrisqueta Pau , Lopez-Guillermo Armando , Montserrat Emili , Monzo Mariano 
Published: April 2020

Abstract
MicroRNAs (miRNA) are small RNAs that act inhibiting the translation of mRNA to protein by complementary binding to his 3′UTR region. In a previous study we analyze the profile of miRNAs in classical Hodgkin lymphoma (HL) and found a 25 miRNAs signature that allows us to discriminate between HL and reactive lymph nodes. And some of them act inhibiting the translation of key genes in B lymphomagenesis. The aim of the study was to analyze if the expression of this miRNAs in the diagnostic samples predict clinical outcome in HL. Eighty nine adult patients (median age, 29 yrs; range, 13–89; males 47%) diagnosed with HL at a single institution between September 1995 and June 2005 have been studied. Seven patients (7.8%) were HIV+. Distribution according to histological subtypes was: nodular sclerosis (79%) and mixed cellularity (21%). Epstein-Barr Virus (EBV) was present in 28% of the samples. First-line treatment consisted of CMOPP/ABV or ABVD. Total RNA was extracted from formalin-fixed paraffin embedded lymph nodes using RecoverAll Total Nucleic Acid Isolation (Ambion). Mature miRNA expression was analyzed by stem loop RT-PCR and Real Time PCR (TaqMan MicroRNA Assay Protocol) in a 7500 Sequence Detection system(AB). Statistical analysis was performed with BRB Array Tools and SPSS 14.0. The characteristics considered were: age (&lt;45 years vs. &gt;45), ECOG, Hasenclever prognostic index (&lt;1 vs 2–4 vs &gt;5), HIV status, Ann Arbor (I–II vs. III–IV), WHO histological classification, bulky disease, EBV (LMP1+ vs LMP1−), ESR (EORTC criteria), and the expression of above-mentioned miRNAs. Clinical outcomes analyzed were relapse rate, disease-free survival (DFS) and overall survival (OS). Out of 89 patients, 75 (84.3%) achieved CR, 7 (7.8%) partial response, 7 (7.8%) were chemoresistant. After a median follow-up of 43 months (1–128), OS was 83% and DFS 74%. Of the 25 miRNAs, miR-135a appears underexpressed in HL samples versus reactive lymph nodes. Moreover, we found two groups of patients relative to miR-135a expression: patients with low expression (Ct&lt;35.4) and patients without miR-135a expression(Ct=&gt;35.4). In the Kaplan Meier analysis the patients without expression of miR-135a had a higher probability of relapse than the patients with miR-135a expression (Log Rank p=0.045). In the multivariate analysis the miRNA was the only prognostic factor for relapse (RR=6.533 p=0.021). In conclusion, miR-135a has as putative target HIF1A, a transcription factor related with hypoxia state that have been related in other tumors with tumoral growth and relapse when it’s overexpressed. Maybe through this target miR-135a play a role in relapse as prognostic value, but a higher number of patients and a functional analysis will be required to validate this new prognostic factor for HL.
AHOD0321: A COG Phase 2 Study of Weekly Gemcitabine and Vinorelbine for Children with Recurrent or Refractory Hodgkin Disease.
Authors: Cole Peter D. , Trippett Tanya M. , Drachtman Richard A. , de Alarcon Pedro , Chen Lu , Schwartz Cindy L. 
Published: April 2020

Abstract
Introduction: This COG Phase 2 study was conducted to assess the efficacy and toxicity of gemcitabine and vinorelbine (GV) in pediatric patients with heavily pre-treated relapsed/refractory Hodgkin disease. Both agents have significant single-agent response rates in this setting, and preclinical data suggest the combination will be at least additive.
Methods: GV was given on days 1 and 8 of each 21d treatment cycle: vinorelbine 25 mg/m2/dose IV push and gemcitabine 1000 mg/m2/dose IV over 100 minutes. Filgrastim 5 mg/kg/dose was started on Day 9 and continued for a minimum of 7 days, until the post-nadir absolute neutrophil count was greater than 1500/μL. Response was evaluated after every two cycles. Patients with measurable responses after two cycles were given the option of going off protocol therapy for stem cell transplantation (SCT). A minimum of two additional cycles was mandated for those with stable disease after two cycles. The statistical analysis of response used a two-stage minimax rule to test the null hypothesis that the response rate is ≤40% with 5% Type I error against an alternative hypothesis of a response rate &gt;65%, with 80% power.
Results: Thirty-one eligible patients with a median age of 17.8 years (range 10.7 – 29) were enrolled. Fourteen were female (45%). All patients had received at least 2 prior chemotherapy regimens and 17 had prior autologous SCT. Toxicity and response data are currently available for 24 patients who completed at least two cycles and 16 who completed four cycles of GV. Among those who completed two cycles, hematologic toxicity was predominant, including grade 3–4 anemia (50%), leukopenia (71%), neutropenia (79%), and thrombocytopenia (83%). Nonhematologic grade 3–4 toxicity included elevated SGPT (38%) or SGOT (21%) and hyperbilirubinemia (4%). No patients developed non-cardiogenic pulmonary edema. There have been three documented infectious complications, including febrile neutropenia, sinusitis, and a urinary tract infection. One patient, with a history of prior mediastinal irradiation, developed pericardial and pleural effusions following cycles 4 and 5 of GV, consistent with gemcitabine-induced radiation recall. There were no toxic deaths. Response data are available for 24 patients of whom 18 (75%) have had measurable responses: 5 CRs, 10 VGPRs, and 3 PRs. All radiographic evaluations of treatment response are undergoing centralized review and full response data for all enrolled patients will be available for presentation.
Conclusion: GV is an effective and well-tolerated re-induction regimen for children with relapsed or refractory Hodgkin disease.
The Recurrent SET-NUP214 Fusion as a New HOXA Activation Mechanism in Pediatric T-Cell Acute Lymphoblastic Leukemia.
Authors: Van Vlierberghe Pieter , Tchinda Joelle , van Grotel Martine , Lee Charles , Beverloo H. Berna , van der Spek Peter , Stubbs Andrew , Cools Jan , Nagata Kyosuke , Fornerod Maarten , Buijs-Gladdines Jessica , Horstmann Martine , van Wering Elisabeth R. , Soulier Jean , Pieters Rob , Meijerink Jules P.P. 
Published: April 2020

Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is mostly characterized by specific chromosomal abnormalities, some occurring in a mutually exclusive manner possibly delineating specific T-ALL subgroups. One subgroup, including MLL-rearranged, CALM-AF10 or inv(7)(p15q34) cases, is characterized by elevated expression of HOXA genes. Using a gene expression based clustering analysis of 67 T-ALL cases with recurrent molecular genetic abnormalities and 25 samples lacking apparent aberrations, we identified 5 new cases with elevated HOXA levels. Using array-CGH, a cryptic and recurrent deletion, del(9)(q34.11q34.13), was exclusively identified in 3 of these 5 cases. This deletion results in a conserved SET-NUP214 fusion product, that was also identified in the T-ALL cell line LOUCY. SET-NUP214 binds in the promoter regions of specific HOXA genes, where it interacts with CMR1 and DOT1L leading to the transcriptional activation of HOXA genes. Targeted inhibition of SET-NUP214 by siRNA abolished expression of HOXA genes, inhibited proliferation and induced differentiation in LOUCY but not in other T-ALL lines. We conclude that SET-NUP214 contributes to the pathogenesis of T-ALL by enforcing T-cell differentiation arrest.
Imatinib Mesylate Reduces Rituximab-Induced Tumor Growth Inhibition In Vivo on EBV-Associated Human B-Cell Lymphoma.
Authors: Némati Fariba , Mathiot Claire , Grandjean Isabelle , Lantz Olivier , Bordier Vincent , Dewulf Sébastien , Ekue Richard , Di Santo James P. , Poupon Marie-France , Decaudin Didier 
Published: April 2020

Abstract
We previously reported an increase of tumor growth inhibition following chemotherapy combined with concomitantly administration of imatinib mesylate [Decaudin D, et al. Int J Cancer2005;113:849–856; Decaudin D, et al. Anti-Cancer drugs2006;17:685–696; Decaudin D, et al. Impact of STI571 on the pharmacokinetics of etoposide and / or ifosfamide in mice. Cancer Res (AACR Annual Meeting) 2006;abstr:5154]. Inversely, combination of imatinib and rituximab was reported in very few cases of patients and remains controversial. In order to explore this particular combination of targeted therapies, we therefore investigated the in vivo impact of rituximab plus imatinib on a B-cell lymphoproliferation. Combination of the tyrosine kinase inhibitor imatinib mesylate (STI571) and the anti-CD20 monoclonal antibody rituximab was evaluated on an EBV-associated B-cell lymphoproliferative disorder xenografted into SCID or Rag2/gc −/− (B-, T-, and NK-) mice. Using SCID mice, we found that STI571 diminished the efficacy of rituximab to inhibit tumor growth in vivo (Figure 1A). Using alymphoid Rag2/gc −/− mice, we showed that the effect of STI571 was not dependent on the presence of NK cells (Figure 1B).
In contrast, serum complement administered after STI571 treatment reversed this inhibitory effect. Finally, using non immunodeficient mice, we observed an in vivo decrease of CD4-positive T-cells and mature B-cell lymphocytes after imatinib administration. We found that STI571 decreased the in vivo efficacy of rituximab via serum protein components that could influence complement-dependent cytotoxicity. In contrast, this effect was not dependent on the presence of NK cells.
Figure Figure
Tyrosine Kinase Inhibitors Only Partially Inhibit AKT-Dependent Signaling in Cells Expressing Oncogenic KIT, FLT3 or ABL Kinases. A Potential Model for Leukemia Cell Resistance to TKIs.
Authors: Schittenhelm Marcus M. , Kampa Kerstin M. , Shiraga Sharon , Kanz Lothar , Heinrich Michael C. 
Published: April 2020

Abstract
Activating mutations of the KIT, FLT3 and ABL tyrosine kinases (TKs) are found in association with hematologic malignancies including subsets of acute leukemias, systemic mastocytosis, and chronic myelogenous leukemia. TK inhibitors (TKIs) have proven clinical activity for treatment of these diseases, but responses are largely partial or incomplete. We and others have previously demonstrated that the small molecule TKIs imatinib (KIT, BCR/ABL), dasatinib (KIT, BCR/ABL), sunitinib (KIT, FLT3), and tandutinib (KIT, FLT3) are potent inhibitors of oncogenic kinases relevant to hematologic malignancies. We now report that inhibition of TK phosphorylation (a surrogate for kinase activation), potently silences STAT and MAPK1/2 signaling - but incompletely inhibits activation of the AKT pathway: Using mastocytosis, leukemia and hematopoietic cell lines with endogenous or exogenous mutant KIT (V560G, D816V), FLT3 (ITD, D835V) or BCR/ABL isoforms, oncogenic TK-dependent downstream pathways were evaluated by immunoblotting. In addition, we determined the effect of treatment with specific TKIs +/– rapamycin on cellular proliferation and the induction of apoptosis. (Auto)phosphorylation of KIT, FLT3 or BCR/ABL results in activation of downstream pathways important for cell viability and cell survival. This includes the MAP Kinase (MAPK), STAT and PI3K/AKT pathways. All tested TKIs were able to potently decrease phosphorylation of members of the MAPK1/2, STAT3 and AKT pathways in cells harboring a corresponding TKI-sensitive oncogenic kinase. Notably, TKI treatment abolished phosphorylation of AKT at the Ser-473 site, whereas the Thr-308 phospho-site remained constitutively phosphorylated. This partial inhibition of AKT activity was insufficient to completely inhibit downstream kinases, such as p70S6Kinase, a known substrate of mTOR (Target Of Rapamycin). The addition of low nanomolar doses of rapamycin completely abrogated p70S6K phosphorylation alone or in combination with TK-inhibition. To determine the biological effect of more completely inhibiting AKT-dependent signaling, we tested TKI in physiological concentrations in combination with low dosage rapamycin (5–20nM). While rapamycin had only weak anti-proliferative effects when administered as monotherapy, combining rapamycin with each TKI demonstrated a strong additive to synergistic inhibitory potency with an up to 4 fold increase of antiproliferative as well as enhanced pro-apoptotic effects when compared to TKI monotherapy. We conclude that TKI inhibition of mutant KIT, FLT3 or ABL signaling is insufficient to globally silence AKT-driven pathways that may contribute to therapy failure. The addition of inhibitors targeting the AKT pathway, such as rapamycin, may improve clinical efficacy of TKI.