bluuebunny/crossref_metadata_2025_split huggingface dataset:
Benzene-Induced Leukemogenesis: Irreversible Inhibition of PTPN2 and Subsequent STAT1 Signaling Alteration By the Hematotoxic Metabolite Benzoquinone
Authors: Duval Romain , Bui Linh-Chi , Mathieu Cécile , Petit Emile , Dupret Jean-Marie , Cools Jan , Guidez Fabien , Chomienne Christine , Rodrigues-Lima Fernando 
Published: October 2019

Abstract
Benzene (BZ) is a chemical compound of industrial and toxicological interest classified as a class I human carcinogen. Environmental and occupational exposure to BZ lead to bone marrow malignancies such as leukemia. The leukemogenic effects of BZ relies on its metabolization in bone marrow cells into reactive metabolites, in particular benzoquinone (BQ) that can react with macromolecules (arylation) and/or induce oxidative stress. Although BZ is well recognized as a leukemogenic chemical, most of the key molecular and cellular mechanisms underlying its hematotoxicity are not fully understood.
PTPN2 is a protein tyrosine phosphatase (PTP) mainly expressed in hematopoietic cells and playing a key role in the homeostasis of the hematopoietic system. In particular, this PTP is an important modulator of growth factors and JAK/STAT signaling pathways. Loss of function analyses in patients with mutation/deletion of the PTPN2 gene and knock-out mouse models indicate that PTPN2 acts as a tumor suppressor in haematologic disorders such as leukemia.
We found that BQ, the prime hematotoxic metabolite of BZ, is an irreversible inhibitor of human PTPN2. Kinetic and biochemical analyses using purified PTPN2 indicated that the irreversible inhibition of the enzyme by BQ is mainly due to arylation of its active site cysteine. Exposure of immortalized human hematopoietic cells (Jurkat T and THP-1 lines) to BQ leads to the irreversible inhibition of endogenous PTPN2 activity with a concomitant over activation of JAK/STAT signaling pathway. Irreversible BQ-dependent inhibition of PTPN2 in cells was found to be mainly due to overoxydation of its catalytic cysteine into sulfinic and/or sulfonic forms.
In Vivo experiments conducted in mice confirmed that exposure to BZ leads to irreversible inhibition of PTPN2 in bone marrow and spleen cells.
Our data provide the first mecanistic evidence that irreversible inhibition of PTPN2, a tumor suppressor tyrosine phosphatase, may contribute to benzene-dependent leukemogenesis.

Disclosures
No relevant conflicts of interest to declare.
Leukemia Related Co-Stimulation / Co-Inhibition Predict T-Cell Attack of Acute Lymphoblastic Leukemia Mediated By Blinatumomab
Authors: Feuchtinger Tobias , Feucht Judith , Kayser Simone , Gorodezki David , Döring Michaela , Blaeschke Franziska , Bösmüller Hans , Quintanilla-Fend Leticia , Schlegel Patrick , Ebinger Martin , Lang Peter J. , Handgretinger Rupert 
Published: October 2019

Abstract
Refractory B-precursor acute lymphoblastic leukemia (ALL) remains an unsolved therapeutic challenge. Various T-cell immunotherapies are promising options in relapsed/refractory B-ALL, like the CD19/CD3-bispecific T-cell engaging antibody Blinatumomab. Until now it has not been possible to determine critical factors for T-cell attack against leukemia that decide on in vivo response or non-response to treatment. Immune-checkpoint molecules regulate immune escape of malignant cells and antibody blockade of these inhibitory pathways enhances antitumor immune responses. Therefore, we investigated the role of co-stimulatory and co-inhibitory molecules for effector-target cell interactions and influence on T-cell attack against leukemia. CD19+ lymphoblast lines, primary pediatric B-ALL bone marrow blasts (n=10) and physiologic CD19+ CD10+ pre-B bone marrow precursors from healthy bone marrow were screened for surface expression of 20 different co-signaling molecules. Surface expression of PD-L1, PD-1, LAG3, CD40, CD86, CD27, CD70 and HVEM revealed differences in stimulatory and inhibitory profiles of pediatric ALL blasts as compared to physiologic cells. Pediatric ALL patients refractory to Blinatumomab-treatment (n=4) as well as patients with relapsed leukemia (n=7) showed increased expression of PD-L1 on blasts. Expression of exhaustion markers PD-1 and TIM-3 was significantly higher on patients' T cells as compared to healthy donors and is induced by T-cell attack against blasts. Blinatumomab-mediated T-cell function was examined in healthy donors as compared to pediatric patients with ALL through analysis of proliferation and effector function. Significant differences in Blinatumomab-induced T-cell function were found to be target-cell dependent and correlated to expression of co-signaling molecules on target cells. Blockade of inhibitory PD-1-PD-L and CTLA-4-CD80/CD86 interactions could further enhance effector T-cell function of healthy donors and patients whereas blockade of co-stimulatory CD28-CD80/86 interactions resulted in reduced T-cell effector and proliferation potential. Combined treatment with Blinatumomab and PD-1 blocking antibody Pembrolizumab was feasible and induced an anti-leukemic immune response in a 12 year old patient with refractory ALL. In conclusion, we show that regulation of T-cell activation and inhibition by co-signaling molecules guides the efficacy of T-cell attack against ALL. Inhibitory interactions between leukemia-induced checkpoint molecules on T cells and their counterparts on ALL regulate in vivo resistance to T-cell immunotherapy and will guide future therapeutic interventions.

Disclosures
Off Label Use: Pembrolizumab.
Phase II Trial Daily Pulse Interleukin-2 Therapy with Famotidine during Marrow and Lymphocyte Recovery in Acute Myeloid Leukemia: LJCC 0605
Authors: Friend Reed , Juskevicius Ridas , Salmon Lauren , Murthy Hemant S. , Xenakis James , Asch Adam S. , Walker Paul 
Published: October 2019

Abstract
Background: Therapeutic advances in treating Acute Myelogenous Leukemia (AML) have been limited in the past two decades. The outcome in patients over the age of 60 and those with high risk cytogenetics remains particularly poor with less than 10% of patients in this age group being cured. High dose Interleukin-2 (IL2) alone in relapsed AML has been shown to induce complete remissions. In this study we report the overall survival (OS), event free survival (EFS), responses and tolerability with IL2 therapy administered during marrow/lymphocyte recovery during induction, re-induction or consolidation.
Methods: Eligibility criteria included confirmed hematopathology diagnosis of AML according to WHO classification (not including acute promyelocytic leukemia) receiving marrow suppressive treatment, a total WBC count above 500 mm3, supported platelet count above 20,000, serum creatinine ≤ 2.0 mg/dl, total bilirubin and AST < 3x upper limit of normal and hemodynamic stability. Famotidine 20 mg IV push daily was administered just prior to the IL2. IL2 therapy was infused at 18 million IU/m2 in 50ml 5% D5 or NS IVPB over 15-30 minutes daily for 5 days. Pre-medication prior to each pulse IL2 dose included acetaminophen 650 mg PO, odansetron 8mg IV, and meperidine 25 mg IV.
Results: 18 pts enrolled with 12 receiving IL2 infusion. The median age was 57.5 (range 32-72). 67% women, 33% men. 8 of 12 patients had AML with myelodysplasia-related changes (including complex cytogenetics), 2 AML with inv(16), 1 AML with 11q23 translocation and 1 therapy-related AML. Median bone marrow blast percentage at diagnosis was 62% (range 32-96). 3 pts received IL2 during induction recovery, 1 during re-induction recovery, 8 during consolidation recovery. 2 pts subsequently underwent allogeneic stem cell transplantation in remission. Median follow up was 328 days (range 99-3207). Estimated 18 month overall and event free survival was 42% (CI 0.15-0.67). Of the 4 pts alive past 4 years, 3 had complex cytogenetics, 2 were greater than age 60. IL2 infusion was well tolerated without any grade 4 toxicities or hemodynamic instability requiring ventilator or hemodynamic support.
Conclusion: IL-2 therapy administered during marrow/lymphocyte recovery after standard induction/consolidation chemotherapy in AML treatment achieved a 33% 4 year overall and event free survival.

Disclosures
No relevant conflicts of interest to declare.
Proteomic Analysis of Reprograming of Mesenchymal Stem/Stromal Cells (MSC) Following Interferon Gamma Identifies Pathways That Are Upregulated in Suppression
Authors: Guan Qingdong , Shpiruk Tanner , Ezzati Peyman , Krokhin Oleg , Gilpin Scott , Doerksen James , Spicer Victor , Bhagwat Swaroop , Wilkins John , Wall Donna A. 
Published: October 2019

Abstract
Assessing potency of mesenchymal stem/stromal cells (MSC) used for immunologic applications such as the treatment of GVHD or other inflammatory disorders has been a challenge. Expression of PD-L1 or production of indoleamine-pyrrole 2,3-dioxygenase (IDO-1) has been proposed as potential potency markers. To screen for other pathways involved with suppression we undertook proteomic analysis of IFN-γ stimulated MSC. MSC isolated and expanded from normal healthy donors to 70-80% confluence were treated overnight with human rIFN-γ (30ng/ml). MSC were harvested using TrypLE Select and then immunologic and proteomic studies were performed. IFN-γ exposure increased a) MSC expression of IDO-1 and PD-L1, b) MSC suppression of 3rd party T lymphocyte proliferation, c) MSC inhibition of development of IFN-γ producing T lymphocytes, and d) MSC promotion of Treg expansion. Cellular proteomic changes that occur with IFN-γ exposures were studied in paired samples of control and IFN-γ treated MSC. Samples were prepared using a modified Filter Aided Sample Prep (FASP) and digests were separated using 2D liquid chromatography and analysed by tandem mass spectrometry. Data was processed with the Global Proteome Machine and only proteins with at least two confident peptides were reported. A total of 7621 proteins were identified of which 5575 were seen in all samples and 232 proteins were significantly upregulated in the IFN-γ treated cells relative to their controls. The proteomic analysis identified constitutive proteins seen in MSC. The upregulated proteins were significantly enriched (p<10-17) for GO processes such as "response to IFN-γ" and "cytokine mediated signaling pathway". Known inhibitory mediators (such as IDO-1, PD-L1, PGE2, galectin-9) were upregulated. Interestingly adhesion molecules (ICAM-1, VCAM-1, and CCL9) were increased. Other proteins with increased expression include Bone Marrow Stromal 2 (BST2). Conclusion: Proteomic analysis of response of MSC to IFN-γ has identified a signature of proteins upregulated with the activation of immune suppressive functions of MSC. Once confirmed these findings will support the development of a potency test for immunosuppressive potential of given MSC preparations - something that is sorely needed in the clinical manufacturing of MSC products.
Acknowledgments: Q.D. is holding a postdoctoral fellowship from MS Society of Canada. This research was supported by The Bihlers' Professorship in Stem Cell Research to D.W.

Disclosures
No relevant conflicts of interest to declare.
Number of Circulating t(14;18) Tumor Cells at Diagnosis Is Related to, but Add to the Prognostic Value of Metabolic Tumor Burden in Follicular Lymphoma
Authors: Delfau-Larue Marie-Helene , Nel Isabelle , VAN Der Gucht Axel , Laboure Gaelle , Verret Benjamin , Hamdane Salma , Gaulard Philippe , Meignan Michel , Haioun Corinne , Copie-Bergman Christiane , Dupuis Jehan , Itti Emmanuel 
Published: October 2019

Abstract
Beside the rare true leukemic forms of follicular lymphoma (FL), low levels of circulating tumor cells (CTC) are detected by PCR in the vast majority of FL patients at diagnosis. By a regular recirculating process, those CTC could reflect the total solid tumor mass. Alternatively, they could represent a subpopulation of tumor cells with distinct molecular profile including adhesion molecules and, as such, could add to the prognostic value of solid tumoral mass previously reported in FL (Dupuis, JCO 2013). In order to address these issues, we retrospectively selected FL patients treated in our institution between 2007 and 2014 who were simultaneously evaluated for both t(14;18) cells in peripheral blood (PB) and FDG-PET/CT tumor mass at diagnosis or at relapse. Absolute quantification of t(14;18) positive cells was performed using quantitative droplet digital PCR (ddPCR). Total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) were calculated from FDG-PET/CT, and baseline clinical characteristics and outcomes were collected. One hundred fourteen patients fulfilled the inclusion criteria. Using a routine 10-4 sensitive biomed 2 t(14;18) PCR assay, 75 had a positive PCR, either in peripheral blood alone (n=37), in peripheral blood and tumor biopsy (n=27) or in tumor biopsy but not PB (n= 11). Absolute quantitative ddPCR was performed for the 56 t(14;18) MBR+ patients. Clinical characteristics are given in Table 1. Median CTC value (number of t(14;18) positive cells out of total peripheral blood nucleated cells) was 1.6 10-3 (range 0-0.96), with only 5 CTC (-) patients and 13 patients with >10% CTC . Median TMTV was 267 cm3 (range 4.61-1900) and median TLG was 1473 (range 10.24-5912). A positive correlation was found between number of CTC and TMTV (R2 = 0.49; P<0.001; Fig.1) and to a lesser extend with TLG (R2 = 0.38; P<0.001). With a median follow-up of 32 months, OS of FLIPI 0-2 patients was 100% vs 87% for FLIPI 3-4 patients (p=0.003). A number of CTC > 6%, TMTV > 432 cm3 and TLG > 2717 tend to be associated with poorer OS (Fig. 2). The combined presence of > 6% CTC and TLG > 2717 allowed to identify a group of patients with 3-year OS of 71%, compared with 100% when both criteria were negative or dissociated (P= 0.01) (Fig. 2). In the subset of 42 patients with an untreated and untransformed FL, incremental prognostic value of circulating mass and metabolic tumor burden remained significant (P=0.03).

Disclosures
Dupuis: ABBVIE: Membership on an entity's Board of Directors or advisory committees; ROCHE: Speakers Bureau.
The Clinical Outcome of Newly Diagnosed Patients >60 Years of Age with Diffuse Large B-Cell Lymphoma (DLBCL) Treated with Standard or Liposomal Chemotherapies
Authors: Ahmed Mohamed Amin , Oki Yasuhiro , Noorani Mansoor , Nastoupil Loretta , Fayad Luis E. , Hagemeister Fredrick B. , Rodriguez Alma , Davis Richard Eric , Westin Jason R 
Published: October 2019

Abstract
Background:
Effective and safe treatment approaches are needed for diffuse large B-cell lymphoma (DLBCL) in the elderly. One approach is to substitute a chemotherapeutic agent with liposomal formulation, expecting greater anti-tumor activity and less toxicity. We have previously conducted two phase II studies using this approach: DRCOP (Clin Lymphoma Myeloma Leuk 2015), utilizing pegylated liposomal doxorubicin in place of conventional doxorubicin in RCHOP, and RCHMP (Brit J Haematol 2013), utilizing liposomal vincristine in place of conventional vincristine in RCHOP. We sought to compare the outcome of patients who are > 60 years of age with newly diagnosed DLBCL, and received DRCOP, RCHMP and RCHOP. This retrospective analysis was in part supported by Spectrum.
Methods:
The outcome of patients with DLBCL who were > 60 years old were analyzed from the study of DRCOP (DLBCL, n=79) and RCHMP (DLBCL elderly, n=32). In addition, we collected the outcome of patients > 60 years old who received standard RCHOP therapy in 2012 (n=39) from our Lymphoma Outcome Database. The baseline clinical characteristics including age adjusted IPI score (aaIPI), determined by stage, LDH and performance status were collected, along with progression free survival (PFS) and overall survival (OS). The retrospective study of patients with this population has been approved by the institutional review board.
Results:
The baseline characteristics were slightly different in all three groups, though statistically not significant; patients with aaIPI 2/3 were 40/79 (51%), 13/32 (40%) and 12/39 (31%) in DRCOP, RCHMP and RCHOP group, respectively (p=0.13). The 3-year PFS rates in aaIPI 0/1 group were 74%, 83% and 81%, respectively. The 3-year PFS rates in aaIPI 2/3 group were 52%, 67% and 48%, respectively. The 3-year OS rates in aaIPI 0/1 were 84%, 94% and 80%, respectively. The 3-year OS rates in aaIPI 2/3 were 63%, 77% and 65%, respectively. None of the survival differences were statistically significant. Kaplan-Meyer curves are shown in Figure.
Conclusion:
In summary, our data showed that liposomal formulation of chemotherapeutic agents produced similar survival outcome to standard therapy. The number of patients analyzed here is small, but these data support the idea of a randomized evaluation of RCHMP against standard RCHOP therapy in a prospective study in patients with DLBCL.
Figure 1. Figure 1.

Disclosures
Off Label Use: Doxil and Marquibo are both not approved for diffuse large B-cell lymphoma but are discussed.. Nastoupil:Celgene: Honoraria; Genentech: Honoraria; TG Therapeutics: Research Funding; Janssen: Research Funding; AbbVie: Research Funding. Rodriguez:Orthobiotech: Research Funding. Westin:Spectrum: Research Funding.
Bispecific T-Cell Engager Antibody Construct Blinatumomab Shows Durable Response in a Long-Term Follow-up Analysis of 38 NHL Patients Treated in a Phase I Trial
Authors: Dufner Vera , Goebeler Maria-Elisabeth , Sayheli Cyrus , Bargou Ralf C. 
Published: October 2019

Abstract
Introduction: Treatment of relapsed/refractory (rr) Non-Hodgkinxs lymphoma of B-cell type (B-NHL) is still challenging and new and more effective therapies are urgently warranted. Blinatumomab, a bispecific T-cell engager (BiTE®) antibody construct, engages CD3+ cytotoxic T cells, resulting in T-cell expansion and lysis of CD19+ B cells. In a prior phase I study, blinatumomab treatment resulted in an overall response rate (ORR) of 69% and 55% in diffuse large B-cell lymphoma (DLBCL), respectively for patients treated at 60 μg/m2/d. Based on this study we here present a single-center analysis on long-term outcome of patients with B-NHL after treatment with blinatumomab. We here report first preliminary data on long-term follow-up of patients with rr NHL after blinatumomab treatment.
Methods: Patients with rr B-NHL who achieved an objective response (PR or CR) upon blinatumomab treatment were eligible for long-term follow-up analysis. Kaplan-Meier estimates for progression free survival (PFS) probability were calculated from first infusion to relapse or death. Patients without an event were censored at last follow-up. This study was conducted in accordance with the Declaration of Helsinki.
Results: Out of 38 treated patients (17 follicular lymphoma (FL), 14 mantle cell lymphoma (MCL), 4 DLBCL, 3 others) 22 received the effective target dose of 60/90 μg/m²/d. 47,4% (CR/PR=28,9%/18,4%, n=38) and 68,2% (CR/PR=40,9%/27,3%, n=22) of the patients experienced response, respectively, whereas only 18,8% of the patients who were not treated with the effective target dose responded to blinatumomab (CR/PR=12,5%/6,3%, n=16). 6 patients are still in ongoing remission.
Median overall survival (OS) of all 38 patients was 1560 days, median PFS 204 days and treatment free survival (TFS) 233 days. Median OS in the 22 patients treated with the target dose was 1793 days, median PFS 492 and TFS 752 days, compared to only 412 days median OS, 46 days PFS and 82 days TFS in the patients, who did not receive blinatumomab in an effective dosage.
Conclusion: Blinatumomab has the potential to induce durable remissions in patients with rr NHL. Our data suggests that treatment at target dose of 60 μg/m²/d is an important prerequisite to achieve long-term remission.
Figure 1. Kaplan Meier analysis shows significantly longer PFS in patients on target dose Figure 1. Kaplan Meier analysis shows significantly longer PFS in patients on target dose

Disclosures
No relevant conflicts of interest to declare.
Pharmacokinetics and Pharmacodynamics after Subcutaneous Dosing of the iNKT Cell Depleting Antibody NKTT120
Authors: Schaub Robert , Thariath Abraham , Scheuplein Felix , Mashal Robert 
Published: October 2019

Abstract
The iNKT cell (invariant Natural Killer T cell) is a unique immune cell that has been shown to be associated with chronic inflammation in sickle cell disease. One approach to reducing iNKT mediated inflammation would be to reduce the number of iNKT cells in the tissue of SCD patients. NKTT120 is a humanized monoclonal antibody directed to the unique T cell receptor of invariant NKT cells that can deplete iNKT cells by antibody dependent cellular cytotoxicity. It recently completed a first in man Phase 1 study that demonstrated that intravenous single doses in adults with SCD specifically reduced iNKT cells without dose limiting toxicity in the therapeutic range of 0.3 and 1.0 mg/kg.
Although intravenous dosing was found to be effective and safe, the ability to dose patients by subcutaneous administration would be an asset to a chronic treatment strategy and patient compliance. The purpose of this study was to assess the bioavailability and the efficacy of NKTT120 administered subcutaneously (SC) to cynomolgus monkeys. Female adult cynomolgus monkeys were administered NKTT120 as a single subcutaneous dose of 0.03, 0.1, 0.3 mg/kg (n=3 each) or as a single intravenous (IV) dose of 0.3 mg/kg (n=3). Animals were monitored for iNKT cell depletion of peripheral blood by FACS analysis and NKTT120 concentration was monitored by ELISA.
All doses resulted in complete depletion of blood iNKT cells without any change in other blood cells. The return of measureable peripheral blood iNKT cells occurred in each group when the plasma concentration was ≤ 100 ng/mL. The time to recovery was dose dependent with measureable iNKT cells found at 4-6 weeks with the 0.03 mg/kg dose and 8-14 weeks with the 0.3 mg/kg IV and SC doses. NKTT120 was dose proportional with time to maximum plasma concentration of 48 hours following SC dosing. Bioavailability of NKTT120 after SC dosing was ~60% and T1/2 was 15 days for the IV dose group and ranged from 11-19 days for the SC dose groups. The duration of iNKT cell depletion and time to recovery for the 0.3 mg/kg SC dose was similar to that observed for the 0.3 mg/kg IV dose group.
The results support a SC dosing strategy for NKTT120 and suggest that similar pharmacodynamic responses could be expected when a therapeutic intravenous dose (0.3 mg/kg) is administered by the subcutaneous route in SCD patients every 3-4 months.
Plasma Concentration vs. Time for NKTT120 Following IV or SC doses to Cynomolgus Monkeys
Figure 1. Figure 1. Figure 2. Figure 2.

Disclosures
Schaub: NKT Therapeutics: Employment, Equity Ownership. Thariath:NKT Therapeutics: Employment, Equity Ownership. Scheuplein:NKT Therapeutics: Equity Ownership. Mashal:NKT Therapeutics: Employment, Equity Ownership.