bluuebunny/crossref_metadata_2025_split huggingface dataset:
EUTOS Score Predicts Long-Term Outcome in Chronic Myeloid Leukemia Patients Transitioning from Pre-Imatinib Era to Imatinib upon Availability
Authors: Deb Pratik , Nath Uttam , Aich Rajarshi , Ray Siddhartha Sankar , Chakrabarti Prantar 
Published: October 2019

Abstract
Background: The introduction of Tyrosine Kinase Inhibitors (TKI) in the management of Chronic Myeloid Leukemia (CML) has been a paradigm shifting phenomenon, yet the prognosis of CML still relies on pre-TKI era methods. Recently, European Treatment and Outcome Study (EUTOS) for CML has proposed a novel scoring system to prognosticate the outcome of treatment with TKIs that only relies on spleen size and basophil count. Although the validity of the newly proposed score has been tested in various populations worldwide, such a study is yet to be performed in the Indian population. We have looked at all three prognostic scores, namely Sokal score, Hasford/Euro score and EUTOS score, in 377 patients initiated with Hydroxyurea but later transitioned to Imatinib when it was available in India.
Methods: A cohort of 377 patients who were diagnosed as Philadelphia chromosome positive CML over the period of 5 years (Jan, 2003 - Dec, 2008) in Institute of Hematology and Transfusion Medicine, Medical College, Kolkata had been included in the study. All the patients were primarily treated with Hydroxyurea but received Imatinib Mesylate at a later time point. All patients received Hydroxyurea for 6 months or more and received Imatinib for at least 1 year at the time of final follow-up. No patient was treated with second generation tyrosine kinase inhibitors. We divided the patients using all three scores: Sokal, Hasford and EUTOS. The prognostic power of each of the scores were tested based on Overall Survival (OS) and Event Free Survival (EFS). Survival probabilities were estimated by the Kaplan-Meier method and compared by pair-wise log rank, Breslow (Generalized Wilcoxon) test and Tarone-Ware test. The pair-wise method was applied in order to detect distinguishing capacity of each test among different groups.
Results: Only EUTOS score stood out as informative as it was able to distinctly separate high and low risk group patients significantly (p < 0.01). The other two scores, namely Sokal and Hasford could not discriminate between the low and intermediate risk group of patients in terms of OS. When we considered EFS instead of OS for the same analysis, the superiority of EUTOS score over its counterparts again became obvious (p < 0.01).
Conclusion: EUTOS score was able to significantly discriminate between high and low risk patients both in terms of 5 year OS and EFS, while Sokal and Hasford/Euro score failed to discriminate between low and intermediate risk patients. We found EUTOS score to be valid in terms of predicting the outcome of CML patients who transitioned from the pre-imatinib era to Imatinib therapy in our population.

Disclosures
No relevant conflicts of interest to declare.
The JAK1/2 Inhibitor Momelotinib Does Not Inhibit Thiamine Uptake in Vitro
Authors: Giacomini Marilyn , Hao Jia , Liang Xiaomin , Chandrasekhar Jayaraman , Twelves Jolyn , Whitney Andy , Lepist Irene , Ray Adrian 
Published: October 2019

Abstract
The clinical development of a selective JAK2 inhibitor, fedratinib, was terminated due to cases of Wernicke's encephalopathy, a disease related to thiamine insufficiency. Furthermore, a recent publication reported potent inhibition of the thiamine transporter 2 (THTR2; SLC19A3) by fedratinib1. This study aimed to determine the potential for other JAK inhibitors to inhibit thiamine transport and to better elucidate the structural basis for inhibition. The effect of the aminopyrimidine containing JAK inhibitors fedratinib, AZD1480, momelotinib, and XL-019 on thiamine transport in Caco-2 cells and HEK293 cells transfected with human THTR1 (SLC19A2) and 2 was assessed. Consistent with the prior publication, fedratinib inhibited thiamine uptake in Caco-2 cells (IC50=0.94 ± 0.08 μM) and THTR2 transfected cells (IC50=1.6 ± 0.52 μM). We also observed inhibition of THTR1 by fedratinib (IC50=7.9 ± 0.97 μM). Another JAK inhibitor, AZD1480, also inhibited thiamine transport, but to a lesser degree (Caco-2, IC50=8.1 ± 0.1 μM). In contrast, momelotinib and XL-019 did not inhibit thiamine transport in any of the systems tested. A pharmacophore model derived from the minimized structure of thiamine suggests that the 2,4-diaminopyrimidine containing JAK inhibitors fedratinib and AZD1480 can adopt a conformation matching several key features of thiamine, while inhibitors lacking the 4-amino group and/or an additional hydrogen bond donor poorly align with thiamine. In summary, these results suggest that not all JAK inhibitors have the potential to inhibit thiamine transport. In particular, momelotinib, currently in Phase 3 clinical trials for the treatment of pancreatic cancer and myelofibrosis, showed no potential to affect thiamine levels.

Disclosures
Giacomini: Gilead Sciences: Employment. Hao:Gilead Sciences: Employment. Chandrasekhar:Gilead Sciences: Employment. Twelves:Gilead Sciences: Employment. Whitney:Gilead Sciences: Employment. Lepist:Gilead Sciences: Employment. Ray:Gilead Sciences: Employment.
A New Prognostic Model for Multiple Myeloma Patients in the Era of Novel Agents
Authors: Cho Hyungwoo , Yoon Dok Hyun , Kim Kihyun , Yoon Sung-Soo , Min Chang-Ki , Eom HyeonSeok , Kim Jin Seok , Lee Je-Jung , Lee Jae Hoon , Suh Cheolwon 
Published: October 2019

Abstract
Introduction
The prognosis of multiple myeloma (MM) is heterogeneous and survival varies from a few months to more than 10 years. Numerous prognostic factors have been identified and several prognostic models were developed to stratify patients into various risk groups. Currently, the international staging system (ISS) is the most widely accepted prognostic model. However, since ISS was established using data collected from 1981 through 2002, only a small portion of patients treated with novel agents (e.g., thalidomide, bortezomib, and lenalidomide) were included in the analysis. Therefore its validity is being challenged in the era of novel agents. We aimed to develop an alternative prognostic model based on easily obtained clinical and laboratory data in the era of novel agents.
Patients and methods
Clinical and laboratory data were collected between January 2000 and April 2013 from 8 tertiary hospitals in Korea. Among 2893 newly diagnosed patients with MM, 1338 were treated with novel agents including thalidomide, bortezomib and lenalidomide at least once. Half of these 1338 patients were randomly selected as a training sample and the other half as a validation sample. A new prognostic model was developed in the training sample, based on significant adverse prognostic factors in univariate and multivariate analysis. This model was then validated in the validation sample.
Results
With a median follow-up duration of 50.8 months (range, 47.1- 54.5) in surviving patients, the median overall survival (OS) in the training sample (669 patients) was 67.8 months. The median OS of patients according to ISS 1, 2, and 3 were 118.0, 67.8, and 50.5 months, respectively. There were no significant difference in the median OS between ISS stage 2 and 3 patients (Figure 1). We identified four independent adverse prognostic factors in the training sample; Serum beta2-microglobulin (Sβ2M) ≥ 3.5 mg/L, elevated serum lactate dehydrogenase (LDH), Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 2 and bone marrow plasma cell percentage (BMPC) ≥ 60%. We used these four adverse prognostic factors to develop a new prognostic model and stratified the patients into three groups; Group 1, no adverse factor; Group 2, 1 adverse factor; Group 3, ≥ 2 adverse factors. We found that there were significant differences in median OS among these three groups (Not reached, 73.0, 40.6 months for group 1,2, and 3, respectively) (Figure 2). This new prognostic model was further validated in the validation sample (Median OS was 128.7, 68.4, and 38.5 months for group 1, 2, and 3, respectively) (Figure 3)
Conclusion
Our study suggests that this new prognostic model based on easily obtainable clinical and laboratory data (Sβ2M, LDH, ECOG PS, BMPC) might be a simple and useful tool to predict prognosis of patients with MM in the era of novel agents.

Disclosures
Kim: CELLTRION, Inc,: Research Funding.
Deletion of Pleiotrophin (PTN), a Vascular Niche Paracrine Factor, Abrogates Chronic Myeloid Leukemia Pathogenesis In Vivo
Authors: Himburg Heather A , Zhao Liman , Chute John P 
Published: October 2019

Abstract
Tyrosine kinase inhibitor (TKI) therapy revolutionized the treatment of patients with chronic myeloid leukemia (CML), but TKI therapy alone is not curative. Leukemic stem cells (LSCs) are considered to be resistant to TKI therapy in CML, although the mechanisms which confer LSC resistance to TKI-mediated eradication remain poorly understood. Our laboratory has previously described the role of PTN, a paracrine factor which is secreted by bone marrow endothelial cells (BM ECs) and is necessary for the self-renewal and regeneration of normal hematopoietic stem cells (HSCs) in vivo. We hypothesized that PTN signaling in the BM vascular niche might also be important in CML pathogenesis and perpetuation of LSCs. In order to test our hypothesis, we crossed SCL-tTA/BCR-ABL mice, which develop CML over time under the control of doxycycline-treatment, with either PTN-/- or PTN+/+ mice, and compared CML pathogenesis in vivo. SCLtTA/BCR-ABL;PTN+/+ mice displayed evolution of chronic phase CML (splenomegaly, increased WBCs, left-shifted myelopoiesis, decreased survival) within 90-120 days. In contrast, SCLtTA/BCR-ABL;PTN-/- mice displayed normal range WBCs, decreased splenomegaly and significantly increased survival over the same time period. At 300 days post-induction of BCR-ABL, 33% percent of SCLtTA/BCR-ABL;PTN-/- mice remain alive compared to only 7% of SCLtTA/BCR-ABL;PTN+/+ mice (p<0.0001). Importantly, treatment of human CML cells with a specific anti-PTN antibody (BD Biosciences) significantly decreased CML colony formation in methylcellulose (P=0.02), whereas normal human CD34+ cells were unaffected. This result suggested the novel possibility that human CML cells may produce PTN in an autocrine manner as a means to propagate disease. These studies suggest that genetic or pharmacologic antagonism of PTN signaling is a potent strategy to inhibit CML pathogenesis. Ongoing studies will determine if PTN-targeted therapy, with or without TKIs, can mediate the eradication of LSCs which are responsible for perpetuation of this disease.

Disclosures
Himburg: Duke University: Patents & Royalties: Patent Application for use of Pleiotrophin as a hematopoietic stem cell growth factor. Chute:C2 Regenerate: Equity Ownership; Duke University: Patents & Royalties: Application to use PTN as growth factor as hematopoietic stem cell growth factor.
Outcomes of Low-Molecular-Weight Heparintreatment for Venous Thromboembolism in Patients with Primary and Metastatic Brain Tumors
Authors: Chai-Adisaksopha Chatree , ALKindi Said Y. , Cheah Matthew , Iorio Alfonso , Crowther Mark A. , Linkins Lori Ann 
Published: October 2019

Abstract
Background: Venous thromboembolism (VTE) is one of the most common complications of patients with brain tumors. There is limited data available in the literature on VTE treatment in these patients compared to other cancer types. We evaluated the efficacy and safety of low-molecular weight heparin treatment for newly diagnosed VTE in patients with primary and metastatic brain tumours at a tertiary care centre.
Methods: We conducted a matched retrospective cohort study of patients with primary or metastatic brain cancer who were diagnosed with cancer-associated VTE. Cases were selected after completion of a retrospective chart review of consecutive patients who were diagnosed with cancer-associated VTE between January 2010 and January 2014 at the Juravinski Thrombosis Clinic, Hamilton, Ontario, Canada. Controls were age- and gender-matched patients with cancer-associated VTE from the same cohort, but without brain tumours. The primary outcome was first recurrent VTE and secondary outcomes were major bleeding and clinically relevant bleeding.
Results: A total of 364 patients with cancer-associated thrombosis were included (182 with primary or metastatic brain tumors and 182 controls). The median follow-up duration was 6.7 (inter quartile range 2.5-15.8) months. The incidence rate of recurrent VTE was 11.0 per 100 patient-year (95% confidence interval [CI]; 6.7-17.9) in patients with brain tumors and 13.5 per 100 patient-year (95% CI; 9.3-19.7) in controls, incidence rate ratio [IRR]; 0.8 (95% CI; 0.4-1.5, p-value=0.43). There was no significant difference in the rate of recurrent VTE in the two groups (log-rank p-value=0.26, Figure 1). The incidence of major bleeding was 8.9 per 100 (95% CI; 5.2-15.4) patient-year in patients with brain tumors versus 6.0 per 100 patient-year (95% CI; 3.4-10.9) in controls, IRR; 0.8 (95% CI; 0.4-1.5, p-value=0.51). There were no significant differences in the risk of major bleeding (Figure 2) and clinical relevant bleeding between the two groups, log-rank p-value 0.9 and 0.8, respectively. When compared to controls, the rate of major gastrointestinal bleeding was lower in patients with brain tumours (0.6% versus 6.0%, p-value=0.003) whereas the rate of intracranial bleeding was higher (4.4% versus 0%, p-value=0.004). Subgroup analysis revealed that the incidence of intracranial bleeding in patients with primary brain tumors was higher than those with metastatic brain tumors, but did not reach statistical significant (6.0% vs 3.5%, p=0.008).
Conclusions: Recurrent VTE, major bleeding and clinical relevant bleeding were not significantly different in patients with cancer-associated VTE in the setting of primary or metastatic brain tumours compared with controls. However, intracranial bleedings occurred more frequently in patients with brain tumours.

Disclosures
Linkins: Pfizer: Honoraria; Bayer: Honoraria, Research Funding.
Time until Transfusion Independence in Haplo-Cord Transplant Is Comparable to Matched Unrelated Stem Cell Transplant, a Single Institution Experience
Authors: Tsang Hamilton C. , Bachegowda Lohith S. , Goel Ruchika , Koshy Nebu V. , Gergis Usama , Hsu Yen-Michael S. , Mayer Sebastian A. , Shore Tsiporah B. , van Besien Koen , Cushing Melissa M. , Vasovic Ljiljana V. 
Published: October 2019

Abstract
Introduction: Stem cell transplant (SCT) is a curative therapy for several advanced hematologic malignancies. In the peri-transplant period, red blood cell (RBC) and platelet (PLT) transfusions are often necessary until engraftment. Time until transfusion independence (TI) is influenced mainly by time to engraftment. Haplo-cord (HC) transplant combines an umbilical cord blood unit graft with a CD34 selected adult haplo-identical graft for the purpose of establishing long term cord engraftment. No prior studies have compared TI between HLA matched related donors (MRD), unrelated donors (MUD) and HC allotransplant recipients.
Methods: Patient demographics, ASBMT disease risk classification, relapse and mortality data for Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS) patients undergoing MRD, MUD, and HC SCT between 1/2012-1/2015 were included. Time until TI for RBC and PLT was defined as the day of the last transfusion with no transfusions in the following 30 days (d). The cohorts were followed for 180d post-transplant. Kaplan-Meier survival method was used to compare time until RBC and PLT transfusion independence between different transplant types and ASBMT risk categories. Data were censored on disease relapse or death. Log-rank test was used to compare the survival probabilities. Statistical analyses were performed using SAS 9.4.0 (SAS Institute, Cary, NC).
Results: A total of 194 AML/MDS patients received MRD (n=63, 32%), MUD (n=76, 39%), and HC (n=55, 28%) SCT. TI was achieved for RBC transfusion in 84%, 74%, and 67% of patients, and for PLT transfusion in 84%, 91%, and 85% of patients for MRD, MUD, and HC respectively. The time to attain RBC and PLT TI was not statistically different between HC and MUD transplants (log-rank p=0.16 and 0.09 respectively) (Fig. 1: A, C). Within the ASBMT high risk strata, no statistical differences in the time to attain RBC (log-rank p=0.15) and PLT (log-rank p=0.55) TI between any transplant types could be detected (Fig. 1: B, D).
Conclusion: Recipients of SCT often have substantial transfusion requirements. No statistically significant difference in time to TI was seen between HC and MUD recipients. No statistically significant differences in time to TI were seen between HC, MUD and MRD recipients in the ASBMT high risk strata. Time until transfusion independence in haplo-cord transplant is comparable to matched unrelated stem cell transplant.
Figure 1. Figure 1.

Disclosures
van Besien: Miltenyi Biotec: Research Funding.
Modular Domains within a Super Enhancer Determine Drug Resistance in Leukemia
Authors: Ohtani Yumi , Xu Shuquan , Petrovic Jelena , Xu Lanwei , Aster Jon C , Pear Warren S. 
Published: October 2019

Abstract

Notch plays roles in T cell development and is a common oncogenic driver in T cell acute lymphoblastic leukemia. Myc is a critical target of Notch in normal and malignant pre-T cells. We and others identified a distal enhancer located >1 Mb 3' of human and murine Myc that binds Notch transcription complexes and physically interacts with the Myc proximal promoter (1, 2). Deletion of a 1 kb region surrounding this enhancer resulted in a block in T cell development and inhibited Notch induced T-ALL induction and maintenance (2). Nevertheless, this 1 kb region contains binding sites for multiple transcription factors; thus, the requirement for specific transcription factors has not been resolved. To determine the precise sequences required for function of the distal enhancer, we used CRISPR/CAS9 to specifically mutate transcription factor binding sites in the Notch-dependent Myc enhancer (NDME). Specific mutation of the RBPj binding site blocked Notch/RBPj binding and inhibited Myc expression and T-ALL cell growth/survival. Acute changes in Notch activation produce rapid changes in H3K27 acetylation across the entire enhancer (a region spanning >600 kb) that correlate with Myc expression. This broad Notch-influenced region comprises an enhancer region containing multiple domains, recognizable as discrete H3K27 acetylation peaks. Specifically mutating the single RBPj binding site abrogated H3K27Ac across this entire 600 kb region. Thus, Notch binding at a single site in the NDME is required for enhancer function and H3K27Ac across a very broad region. Furthermore, the Notch-regulated distal enhancer is comprised of individual enhancers that are uniquely sensitive to Notch or BET domain inhibitors. By selecting tumor cells resistant to each inhibitor, we show that the change in drug sensitivity results from selective use of these individual enhancers that are located within the broad Notch regulated region. These data not only provide insights into enhancer function but suggest strategies to treat T-ALL, including drug resistance, by therapeutically targeting these enhancers.
References:
1. Ohtani et al., Proc Natl Acad Sci USA 111:E4946, 2014, PMID: 25369933
2. Herranz et al., Nature Med, 20:1130, 2014, PMID: 25194570

Disclosures
Pear: Rockefeller University: Patents & Royalties; Pfizer: Equity Ownership; Amgen: Equity Ownership.
Identification of Activity Enhancement Residue of Human FVIII and Novel Factor VIII Variant for Human Gene Therapy
Authors: Firrman Jenni A. , Wang Qizhao , Xiao Weidong 
Published: October 2019

Abstract
Gene therapy for Hemophilia A using the recombinant Adeno-associated virus (rAAV) offers an alternative to FVIII protein infusions; However, due to limitations associated with rAAV and the FVIII protein itself, the end result is transgene expression below therapeutic limits. One approach to improving the therapeutic value of rAAV gene therapy for HA is to engineer a more active FVIII protein through genetic modifications. Preliminary testing revealed that canine FVIII Light Chain (kLC) enhances human FVIII coagulation activity. Through the process of engineering, evaluation, positive and negative selection of kLC, key amino acids in canine factor VIII were identified. These amino acids were incorporated into human factor VIII and a new version of human factor VIII, hFVIII.JF12, was engineered.
The hFVIII.JF12 is a human FVIII B-domain deleted construct containing 12 amino acid changes in the light chain that work together to enhance coagulation activity. In vitro, hFVIII.JF12 resulted in a 4.3 fold increase in clotting activity, but no increase in protein production. CD4KO/HA mice injected with rAAV vector carrying the hFVIII.JF12 gene produced an average 4.6 fold increase in clotting activity compared to those injected with hFVIIIBDD. An ELISA revealed no significant difference in protein production between these two groups of injected mice. In order to determine the mechanism of enhancement, the hFVIIIBDD and hFVIII.JF12 proteins were purified and functional properties analyzed. Results demonstrated that the hFVIII.JF12 protein produced a specific activity of 39,153.69 Units/m. This is a 6.28 fold increase over hFVIIIBDD specific activity, which was 6,237.92 Units/mg. Measurement of conversion from FX to FXa revealed that the hFVIII.JF12 protein generated a higher amount of FXa at a quicker rate.
The hFVIII.JF12 construct is novel because it enhances FVIII activity both in vitro and in vivo through modifications to the light chain based on the kLC. This will be beneficial in the context of both gene and protein therapy because the protein is more specifically active. This research is also innovative because it demonstrates a novel method of enhancing transgene expression of FVIII delivered by an AAV vector through modifications to the gene itself.

Disclosures
No relevant conflicts of interest to declare.
Heat Shock Factor 1 Promotes NF-Kb and B-Cell Signaling in a Preclinical Model of Chronic Lymphocytic Leukemia
Authors: Rao Rekha , Home Trisha , Yacoub Abdulraheem , Shi Huidong , Saluja Ashok , McGuirk Joseph , Ganguly Siddhartha 
Published: October 2019

Abstract
Recent studies have shown that overexpression of Heat Shock Factor (HSF) 1 in aneuploid tumor cells can overcome deficiencies in heat shock protein (HSP) 90-mediated protein folding and restore protein homeostasis. In this study we determined the mechanisms by which HSF1 promotes HSP90 function and CLL pathogenesis using CLL as model system. We report that HSF1 is overexpressed in CLL and treatment with triptolide (a small molecule inhibitor of HSF1) induces apoptosis in cultured and primary CLL B-cells. Mechanistically, we demonstrate that knockdown of HSF1 or its inhibition with triptolide results in the reduced association of HSP90 with its kinase co-chaperone cell division cycle 37 (CDC37), leading to the partial depletion of HSP90 client kinases, Bruton's Tyrosine Kinase (BTK), c-RAF and cyclin-dependent kinase 4 (CDK4). RNA-sequencing of control and HSF1-knockdown CLL cells revealed that HSF1 regulates the transcription of upstream modulators of the NF-kB pathway including MYD88 and TLR1. Consequently, treatment with triptolide or knockdown of HSF1 inhibits NF-kB signaling in CLL cells. In an in vivo model of CLL, tail vein injection of luciferase-expressing Mec-1 cells into Rag2-/-IL2Rγc-/- mice followed by daily intraperitoneal injection of minnelide (a pro-drug of triptolide) for 28 days reduced in vivo disease burden and conferred significant survival advantage (p<0.0003) to treated mice compared to vehicle controls. Minnelide treatment also attenuated NF-kB and BTK signaling in vivo. In conclusion, our study provides a strong rationale to target HSF1 in CLL and test the activity of minnelide against human CLL.

Disclosures
Saluja: Minneamrita Therapeutics: Equity Ownership.