bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing Notification Of Hospital Admission: A Fellow-Led Quality Initiative
Authors: Kasi Loknath Kumar Anup Kumar , Satyan Megha Teeka , Pal Aroop , Sarah Taylor
Published: October 2019

Background

There is increasing attention nationally to improve the continuum of care for patients. The advent of hospitalists has created significant challenges in effective communication of patient care. The quality and reliability of hospital admission notification of patients to primary hematologists/oncologists, including fellows, anecdotally was a concern.

Objective

To determine the current level of satisfaction for University of Kansas Cancer Center practice (faculty and fellows) with notification of admission to University of Kansas Hospital and determine desired means of notification by Cancer Center practice. Based on a survey, an intervention would be developed to improve quality and satisfaction.

Methods

A pre-intervention survey was administered to determine the desired means and satisfaction of KU Cancer Center faculty and fellows. Based on the results of the survey, an intervention was devised with the use of the Electronic Medical Records (EMR) to generate an inbasket message with desired details. A post-intervention survey will be administered to evaluate the intervention.

Results

Pre-intervention survey was completed by 23 of 51 (45%) invited participants. 16 of 23 (70%) who completed the survey were not notified of admissions. The remaining 7 (30%) participants were notified of admissions but there were no standard means of notification [Fig 1]. Only 4 (17%) of the participants were satisfied and 12 (52%) of the participants were dissatisfied and very dissatisfied with admission notification [Fig 2]. Only 3 (13%) were satisfied and 14 (60%) were dissatisfied and very dissatisfied with the timeliness of admission notification [Fig 3]. The top 3 preferred means of admission notification desired by participants included in-basket message in EMR (n=18), email (n=18), text page (n=14) [table 1]. The top 2 preferred content of the notification desired by participants included Admission Date (n=20) and Diagnosis (n=20) [table 2]. Post-intervention survey is yet to be completed but preliminary results are promising, and will be reported at the time of poster presentation.

Conclusion

A key component of the continuity of care for patients is good, timely communication, including the notification of the admission of patients. A fellow-led intervention highlights opportunities for fellows to participate and execute quality initiatives that meet both educational and professional needs. Utilization of the EMR and technology can improve communication, as demonstrated by this initiative. We achieved great improvement in the provider satisfaction with the quality and timeliness of notification, which should facilitate better care for patients.

Disclosures:

No relevant conflicts of interest to declare.
Prognostic Implication Of Circulating Vascular Endothelial Growth Factor In Patients With Diffuse Large B-Cell Lymphoma
Authors: Lee Hyewon , Eom Hyeon-Seok , Kim Min Kyeong , Kim Hyun-Ju , Park Weon Seo , Kong Sun-Young
Published: October 2019

Background

Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis and progression of cancer, and blood level of VEGF has been known to predict of outcome in several types of cancer. However, the impact of blood VEGF levels on prognosis of diffuse large B-cell lymphoma (DLBCL) has not been fully elucidated. Here we investigated the prognostic implication of circulating VEGF levels in patients with DLBCL.

Patients and Methods

The study involved 127 DLBCL patients treated by rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) at National Cancer Center, Korea. Both serum and plasma of the patients were obtained at diagnosis. VEGF were measured using ELISA kit (R&D systems) according to manufacturer’s guidance. We investigated the correlation between clinical parameters and blood VEGF levels. Survival rates and hazard ratios (HRs) in terms of risk for overall survival were determined using Kaplan-Meier method and Cox proportional hazard regression analysis.

Results

The median patient age was 56 years, and 75 (59%) patients were men. Clinical characteristics and international prognostic index (IPI), including age, performance, lactate dehydrogenase (LDH), Ann Arbor stage and extranodal involvement were evaluated. The mean (±SD) value of serum and plasma VEGFs were 713 (±599.8) and 107 (±164.4) pg/mL, and they were correlated as r=0.61 (p<0.001). Both serum and plasma VEGF showed the significant (p<0.01) correlation with serum LDH level, Ann Arbor stage and multiple extranodal involvement, but not with age, gender nor performance. IPI showed strong prediction for prognosis in our data set (HR 3.80, 95%CI 1.64-8.81, p=0.02), and the VEGF levels of high/high-intermediate IPI group were significantly higher than those of low/low-intermediate group [serum VEGF 1088(±838.0) and 557(±377.2), p<0.001 and plasma VEGF 79(±131.6) and 176(±212.2), p=0.002]. With the median follow-up of 44 months, high serum VEGF levels (higher than the median) were significantly associated with short survival (HR 2.74, 95%CI 1.13-6.60, p=0.025), though the plasma VEGF levels did not show the association similar to the serum samples (HR 1.40, 95%CI 0.63-3.12, p=0.414). The patients with higher serum VEGF than the median value showed significantly lower survival rate compared to the low group (3-year survival rates, 68.6% vs. 85.6%, p=0.019).

Conclusion

These findings suggest that high serum VEGF levels can predict poor clinical outcome in patients with DLBCL. This study also represents the different type of specimen for VEGF measurement affected the results. We might have to select adequate specimen type for VEGF measurement, although further validation in large cohort and mechanism studies for this data are warranted.

Disclosures:

No relevant conflicts of interest to declare.
The Prognostic Significance Of DUSP3 In DLBCL
Authors: Fang Rachel R. , Xu Yulian , Qi Chen-feng , Morse Herbert , Zhou Jeff Xiwu
Published: October 2019

DUSP3 (also called VHR) is a member of the dual-specificity protein phosphatase family which can dephosphorylate target proteins at phosphoserine/threonine and phosphotyrosine residuals. There are evidences that DUSP3 is highly expressed in cervical and prostate cancers, and may exert its function in inhibiting apoptosis. By analyzing publicly available data on diffuse large B-cell lymphoma (DLBCL), we found that the expression levels of DUSP3 mRNA were inversely associated with overall survival (OS) in DLBCL. Patients with low levels of DUSP3 mRNA had significant longer OS than did those with high levels of DUSP3 (P=0.0002) (Figure 1). The association between the levels of DUSP3 mRNA and clinical outcome was confirmed using an independent DLBCL cohort. To decipher the role of DUSP3 in DLBCL, we used lentiviral system to stably express shRNA against DUSP3 in the DLBCL cell line, OCI-Ly01. Reduced expression of DUSP3 was associated with significantly decreased proliferation of cells as compared to the control group (P<0.001) (Figure 2). Because the standard chemotherapy for DLBCL depends largely on induction of DNA damage, we were interested in examining possible effects of DUSP3 on the DNA damage response. We found that the levels of phosphorylated H2A.X, a marker for DNA damage response, were significantly increased in cells with reduced levels of DUSP3 (P<0.01) (Figure 3). This may suggest that low levels of DUSP3 in tumor tissues render cells more vulnerable to therapy-induced DNA damage, leading to increasing efficacy of chemotherapy. More molecular and animal studies are underway to determine if DUSP3 can serve as a prognostic biomarker for DLBCL and to identify the underlying molecular mechanisms.

Disclosures:

No relevant conflicts of interest to declare.
Improved Risk Stratification With Addition Of Male Sex (S) To The Elderly International Prognostic Index (S-EIPI) For DLBCL Patients > 60 Years Treated With R-CHOP: An International Collaboration Of The US Intergroup, German High-Grade Non-Hodgkin Lymphoma Study Group and Groupe d’Etude De Lymphome d’Adultes
Authors: Advani Ranjana H. , Hong Fangxin , Habermann Thomas M. , Li Hailun , Kahl Brad S. , Morrison Vicki A. , Weller Edie A. , Varma Gaurav , Fisher Richard I , Peterson Bruce A. , Cheson Bruce D. , Gascoyne Randy D. , Horning Sandra J. , Bousetta Sami , Coiffier Bertrand , Ziepert Marita , Pfreundschuh Michael
Published: October 2019

Background

We have previously reported and validated that the E-IPI, provided better discrimination of overall survival (OS) than the IPI for DLBCL patients > 60 years of age treated with R-CHOP (Advani et al., BJH 2010 and 12-ICML 2013 Abstract 222). Recent reports suggest that males > 60 years treated with R-CHOP have worse outcomes likely related to differences in rituximab clearance (Muller et al., Blood 2012). In this study, we explored if the addition of male sex to the E-IPI further improved risk stratification.

Methods

DLBCL patients > 60 years treated with R-CHOP on the E4494, RICOVER-60 and GELA 98-5 trials were included. A multivariate analysis was performed to assess whether male sex is an independent prognostic factor for OS in addition to the five E-IPI risk factors, E-IPI score, and E-IPI risk group. Male sex (S) was added as an additional risk factor to the E-IPI (S-EIPI, 0-6) and patients regrouped according to the number of risk factors: low (L)=0-1, low intermediate (LI)=2, high intermediate (HI)=3 and high (H)=4-6 based on the observed OS using Kaplan-Meier curves. C-statistic was used to compare the discrimination ability. The 5 year OS was estimated using the Kaplan-Meier method.

Results

1079 patients (E4494, n=267; RICOVER-60, n=610; GELA 98-5, n=202) with a median follow-up of 8.9 years were included. In multivariate analyses, male sex was a significant independent predictor for OS adjusting for all five E-IPI factors, (HR 1.5, p < 0.0001), E-IPI score (HR 1.42, p < 0.001), and E-IPI risk group (HR 1.42, p < 0.001) (Table 1). C-statistic was 0.66 for S-EIPI and 0.64 for EIPI. Incorporation of sex into the E-IPI shifted 35% patients to higher risk groups, including 110 patients into the highest risk group (Table 2). The estimated 5 year OS for the S-EIPI L, LI, HI, and H risk groups was 87%, 70%, 58%, and 40%, respectively (Table 3). Compared to E-IPI, the 95% C.I. did not overlap among S-EIPI risk groups.

Conclusion

For DLBCL patients >60 years treated with R-CHOP, our results suggest the addition of male sex to the E-IPI may improve categorization of patients into well-defined clinically relevant risk groups. Patients with low risk S-EIPI have an excellent outcome (5 year OS 87%). Patients with high risk S-EIPI have a 5 year OS of only 40% and therapies beyond standard R-CHOP need to be explored.

Disclosures:

Horning: Genentech: Employment; Roche: Equity Ownership.
Significant Activity Of The mTOR Inhibitor Sirolimus and HDAC Inhibitor Vorinostat In Heavily Pretreated Refractory Hodgkin Lymphoma Patients
Authors: Janku Filip , Garrido-Laguna Ignacio , Velez-Bravo Vivianne , Falchook Gerald S. , Subbiah Vivek , Hong David S. , Oki Yasuhiro , Westin Jason R. , Nunez Cesar A. , Fayad Luis E , Kwak Larry W. , Shpall Elizabeth J , Wheler Jennifer J. , Liang Winnie , Salhia Bodour , Meric-Bernstam Funda , Kurzrock Razelle , Fanale Michelle
Published: October 2019

Background

Preclinical models have suggested that HDAC and mTOR inhibitors have synergistic antineoplastic activity in Hodgkin lymphoma and other cancers by reducing the activity of AKT, mTOR and HDAC.

Methods

We designed a phase I study to determine the safety of the mTOR inhibitor sirolimus (1mg-5mg PO daily q 28 days) and HDAC inhibitor vorinostat (100mg-400mg PO daily q 28 days) in advanced cancers with an expansion cohort at the recommended phase 2 dose (RP2D) of sirolimus 4mg and vorinostat 300mg for patients with refractory classical Hodgkin lymphoma. The expansion cohort included optional pre- and post-treatment tumor biopsies, peripheral blood mononuclear cells (PBMCs), plasma/serum collections for pharmacodynamic (PD) and pharmacokinetic (PK) endpoints.

Results

A total of 16 patients (men, n=8; women, n=8), median age 33 years, median of 6.5 prior therapies (including autologous SCT [n=15], autologous and allogeneic SCT [n=4]) were enrolled in dose escalation (n=1) or RP2D (n=15) cohorts. At the median follow-up of 3.2 months, 15 (94%) patients demonstrated decreased FDG uptake including 2 CRs (13%) and 5 PRs (31%) using CHESON criteria, with a total CR+PR rate of 44%. The median reduction of tumor was -27% (-100% to +20%, Figure). The estimated median time-to-treatment failure has not been reached and 63% of the patients continued on therapy with further improvement in their level of disease response. Major grade 3-4 treatment-related toxicities included grade 3 thrombocytopenia (4 patients, 25%), grade 4 thrombocytopenia (6, 38%), grade 3 anemia (1, 6%), febrile neutropenia (1, 6%) and led to treatment interruptions and/or dose modifications in 10 (63%) patients. Five (31%) patients had archival tissue available for targeted next-generation sequencing and one patient had a loss of TSC2, an abnormality that putatively activates mTOR. This patient has had a continuing response to therapy (-56%) for 8.4+ months. PD studies in pre- and post-treatment tumor biopsies, PBMCs and plasma as well as PK analysis continue.

Conclusion

The combination of sirolimus and vorinostat is well tolerated with encouraging activity in very heavily pretreated patients with Hodgkin lymphoma refractory to standard therapies. Enrollment continues.

Disclosures:

Off Label Use: sirolimus - mTOR inhibitor vorinostat - HDAC inhibitor.
Pomalidomide Augments Fetal Hemoglobin Production In Primary Erythroid Cells By a Novel Mechanism Modulating BCL11A But Not KLF-1
Authors: Appiah-Kubi Abena O. , Blanc Lionel , Singh Sharon A. , Didier Sebastien , Dsilva Sehba , Chan Kyle W.H. , Lipton Jeffrey Michael , Liu Johnson M.
Published: October 2019

Fetal hemoglobin (HbF) is a known modifier of sickle cell disease (SCD) severity. KLF-1 is a regulator of the globin switch. It does so by increasing beta-globin production and up-regulating BCL11A, a repressor of HbF synthesis. Pomalidomide, a second generation immunomodulatory drug (IMiD), regulates HbF and F-cell production during erythropoiesis in human CD34+ cells. The mechanism by which pomalidomide enhances F-cell production is not well understood. In this study, CD34+ cells were obtained after purification of peripheral blood and positive selection and cultured using a three-phase in vitro liquid culture system which recapitulates erythropoiesis, including terminal differentiation and enucleation, in the presence of no drug, pomalidomide, hydroxyurea, or dimethyl sulfoxide (DMSO; vehicle control). Erythroid differentiation was assessed morphologically and by flow cytometry using the transferrin receptor and glycophorin A as markers of erythroid maturation. Flow cytometry was used to quantify F-cells. RT-qPCR was used to quantify mRNA expression of BCL11A, KLF-1, and gamma-globin. Western blot was used to measure the total expression levels of BCL11A. In this culture system pomalidomide increased F-cells more than hydroxyurea in both SCD and normal control erythroid cultures. There was a significant decrease in BCL11A expression levels, a repressor of HbF synthesis, with pomalidomide but not with hydroxyurea. This decrease was seen in both SCD and normal samples. KLF-1 was not affected by pomalidomide. These findings suggest a very different mechanism of action for pomalidomide versus hydroxyurea in increasing F-cell production. Pomalidomide appears to target the erythroid specific BCL11A but not the more pleiotropic transcription regulator KLF-1. Since the F-cell production was augmented in the presence of pomalidomide in controls as well as SCD erythroid cultures this study suggests a role for pomalidomide in the pharmacologic augmentation of fetal hemoglobin levels, perhaps in addition to hydroxyurea, not only in SCD but in any beta-hemoglobinopathy.

Disclosures:

Chan: BioTheryX Inc: Employment.
Aberrant Expression Of miRNA and mRNA Of Cell Cycle and Adhesion-Related Genes In Bone Marrow Stroma Cells Derived From Patients With Multiple Myeloma
Authors: Berenstein Rimma , Wolfgang Blau Igor , Nogai Axel , Wächter Marlies , Pezzutto Antonio , Dörken Bernd , Blau Olga
Published: October 2019

Multiple myeloma (MM) is a B-cell malignancy characterized by accumulation of malignant plasma cells (PC) within the bone marrow. The bone marrow microenvironment such as bone marrow stroma cells (BMSC) supports MM disease progression, resistance to chemotherapy, protects the tumor cells against apoptosis and causes osteolytic bone disease and angiogenesis.

The aim of this study was to identify constitutive genetic alterations in BMSC derived from patients with MM (MM-BMSC) in comparison to BMSC from healthy donors. For BMSC selection, mononuclear cells were isolated from fresh bone marrow aspirates and were further expanded in cell culture. We studied 25 MM patients and 5 healthy donors. Senescence status was determined in passage 1 of cell cultures. MM-BSMC displayed a considerably higher percentage of senescence cells (p<0,05). We investigated the expression of cell cycle and adhesion-associated genes (CCNE1, CCND1, CDKN1B, VCAM, ICAM, IKK-alpha) in BMSC (passage 4) using SYBR-Green Real-Time PCR and relative quantification by linear regression.

A downregulation of CCNE1 (p=0,05), CDKN1B (p=0,29), and an upregulation of CCND1 (p=0,05), VCAM-1 (p=0,33), ICAM-1 (p=0,33), and IKK-alpha (p=0,05) was demonstrated. Furthermore, the expression profile of miRNAs, targeting the analyzed mRNA genes or correlating with senescence, was studied (miR-16, miR-221, miR-126, miR-223, miR-485-5p and miR-519d). For miRNA detection treatment with Poly(A)-Polymerase and cDNA-Synthesis with a Poly(T)VN-Adaptor primer were carried out following an amplification with an universal reverse primer corresponding to the adaptor sequence and a miRNA-specific primer. miR-16, miR-223, miR-485-5p and miR-519d were significantly upregulated, (p=0,02; p=0,004; p=0,02; and p=0,002, respectively), whereas miR-221 and miR-126 showed no considerable differences to BMSC obtained from healthy donors. Next we investigated incubation of immunmodulatory drug Lenalidomid in BMSC cultures. Cells were treated with 10 µM Lenalidomid over 72 hours and expression was normalized to a 0,01 % DMSO control. Significant difference in gene expression were visible for ICAM-1 (p=0,01). For CDKN1B (p=0,16) and VCAM-1 (p=0,12) we demonstrated changes in gene expression.

Our results indicate aberrant expression of cell cycle and adhesion-related genes, such as CCNE1, CCND1 and CDKN1B VCAM-1, ICAM-1 and IKK-alpha in MM-BMSC as compared with healthy donors. Furthermore, we found significant upregulation of miR-16, miR-223, miR-485-5p and miR-519d. Further investigation are needed to determine molecular mechanisms in MM-BMSC and PC interaction that lead to constitutive changes in BMSC characteristics and gene expression patterns.

Disclosures:

No relevant conflicts of interest to declare.
Monitoring Minimum Residual Disease In Multiple Myeloma Patients By LC-MS/MS
Authors: Bergen H. Robert , Murray David L , Jelinek Diane F. , Tschumper Renee C. , Barnidge David R , Ramirez-Alvarado Marina , Dasari Surendra
Published: October 2019

Proteomics with great sensitivity and specificity effectively analyzes proteins by prior tryptic digestion and subsequent analysis by LC-MS/MS of the tryptic digest. We have utilized this approach in the development of a LC-MS/MS method to characterize minimum residual disease in multiple myeloma. The abundant antibodies produced by multiple myeloma plasma cells are identical and appear as a spike (M-spike) upon protein electrophoresis. The M-spike and histological examination of the bone marrow constitute part of the myeloma diagnostic repertoire. Upon treatment, myeloma cells and the antibodies they produce are reduced in number and amount and become increasingly hard to detect. The bone marrow biopsy serves as the “gold standard” test for clinical remission.

We have developed a sensitive test for the presence of the monoclonal antibody produced by the plasma cells which may serve as a substitute for invasive bone marrow biopsy. We have focused on tryptic peptides comprising the variable CDR regions of the Ig light chains that are unique to each patients antibody clone. Utilizing 2-5 µL of patient plasma/serum from the initial M-spike sample we have utilized SDS-PAGE to yield a crudely purified immunoglobulin light chain. The light chain band is isolated, reduced, alkylated and trypsin digested with subsequent LC-MS/MS analysis to identify CDR specific tryptic peptide(s). These can be identified as variable peaks (elution time and mass) in a base peak ion chromatogram where constant region peptides of either lambda or kappa light chains (clone dependent) serve as “internal standards” for identifying the CDR tryptic peptides. The peptide’s mass and its corresponding MS/MS spectra are unique to this CDR tryptic peptide and this patient’s clone. The unique diagnostic peptide is isolated in subsequent samples by immunoaffinity purification of the target kappa/lambda clone, SDS-PAGE separation and LC-MS/MS analysis of the light chain gel band. An extracted ion chromatogram is generated based upon the CDR peptides identified in the initial analysis of the M-spike sample. In patients in clinical remission the presence of a significant signal from the targeted peptides indicates that targeting a CDR peptide from the M-spike protein is more sensitive than currently available diagnostic tools including immunofixation. Comparison of this test to the gold standard bone marrow biopsy will be examined.

Disclosures:

Barnidge: Mayo Foundation: provisional patent application for technology, provisional patent application for technology Patents & Royalties.
Impact Of Dialysis-Dependent Renal Failure At Time Of Myeloma Diagnosis On Overall Survival - a 15-Year Single Centre Analysis
Authors: Murphy Philip T , Baldeo Cherisse , O'Kelly Patrick , Sargant Jeremy , Thornton Patrick , McCloy Mary , Conlon Peter , Magee Colm , Denton Mark , Quinn John
Published: October 2019

In myeloma, the use of autologous stem cell transplantation in younger patients as well as the introduction of thalidomide, lenalidomide and bortezomib has resulted in improvement in long-term survival of both younger and older patients. Bortezomid and high dose dexamethasone is currently recommended to treat newly diagnosed myeloma patients presenting with renal impairment and may lead to varying degrees of improvement in renal function. We have assessed not only survival trends for all patients diagnosed at our centre over the past 18 years but also the survival of the subset of patients with severe renal impairment who required dialysis at diagnosis.

All patients diagnosed with myeloma at our centre between January 1995 and December 2012 were included. We constructed Kaplan-Meier curves and used the Breslow generalised Wilcoxon test to evaluate overall survival (OS) patterns (diagnosed in three calendar periods: 1995-2000; 2001-2006; 2007-2012) for our total patient population as well as the subset of patients who required dialysis within 4 weeks of diagnostic bone marrow test.

262 patients (60.3% males) were diagnosed between 1995 and 2012. For all patients, median OS significantly increased from 13.2 months in period 1995-2000 to 27 months in period 2001-2006 with median OS not yet reached in period 2007-2012 (p=0.0001). In patients 70 years old or less, median OS significantly increased from 25.4 months in period 1995-2000 to 46.7 months in period 2001-2006 with median OS not yet reached in period 2007-2012 (p=0.0482). Improved median OS was also seen in patients > 70 years old: 4.4 months in period 1995-2000, 17.4 months in period 2001-2006 and 25.1 months in period 2007-2012 (p<0.0001). In contrast, patients requiring dialysis at diagnosis (n = 44) had much worse outcomes: median OS in the period 1995-2000 was 2.8 months and although there was a slight improvement in median OS in the period 2001-2006 (p=0.0318), there has been no further improvement in median OS in the period 2007-2012.

In our overall myeloma patient population, median OS has continued to increase over the time periods 1995-2000, 2001-2006 and 2007-2012, both for younger patients 70 years old or less and older patients >70 years old. Patients requiring dialysis at diagnosis, however, continue to have much poorer median OS, despite the use of bortezomib and dexamethasone containing regimens in recent years. The possible benefit of improved supportive measures and the early use of other emerging novel agents in this poor prognostic subgroup should be explored in the clinical trial setting.

Disclosures:

No relevant conflicts of interest to declare.
Deletion Of Fanca Or Fancd2 Dysregulates Treg Activity and Exacerbates Gvhd In Mice
Authors: Du Wei , Erden Ozlem , Wilson Andrew , Sipple Jared , Schick Jonathan , Mehta Parinda A. , Davies Stella M. , Steinbrecher Kris , Pang Qishen
Published: October 2019

Fanconi anemia (FA) is a genetic disorder associated with bone marrow failure and leukemia. Recent studies demonstrate fundamental immune defects in FA. However, the mechanisms that are critical for FA immunodeficiency are not known. Here we report that deletion of Fanca or Fancd2 dysregulates the suppressive activity of regulatory T cells (Tregs) and exacerbates graft-versus-host disease (GVHD) in mice. Recipient mice of Fanca-/- or Fancd2-/- bone marrow chimeras exhibited severe acute GVHD after allogeneic bone marrow transplantation (BMT). Further study showed that T cells from Fanca-/- or Fancd2-/- mice induced higher GVHD lethality than those from WT littermates. Mechanistically, FA Tregs possessed lower proliferative suppression potential compared to WT Tregs, as demonstrated by in vitro proliferation assay and BMT. Analysis of CD25+Foxp3+ Tregs indicated that loss of Fanca or Fancd2 dysregulated Foxp3 transcriptional activity. Additionally, CD25+Foxp3+ Tregs of Fanca-/- or Fancd2-/- mice were less efficient in suppressing the production of GVHD-associated inflammatory cytokines. Consistently, incremental NF-kB transcriptional activity was observed in infiltrated T cells from FA GVHD mice. Conditional deletion of p65 in FA Tregs desreased GVHD mortality. Our study uncovers an essential role for the FA proteins in maintaining Treg homeostasis and suggests that targeted blocking NF-kB signaling within T cells represents an attractive therapeutic strategy to ameliorate GVHD in FA.

Disclosures:

No relevant conflicts of interest to declare.
Differential Regulation Of Chemokine Receptor Expressions On T Lymphocyte Subsets In Healthy Donors After Mobilization With Rhg-CSF and Its Correlation With Acute GvHD
Authors: Ren Han-Yun , Wang Meng , Ma Xiang-Juan , Dong Yu-Jun , Qiu Zhi-Xiang , Liu Wei
Published: October 2019

Introduction

This study is aimed to investigate chemokine receptors (CCR5, CCR6, CCR7, CCR9, CXCR3 and CCR2) expression on T cell subsets in healthy donors after mobilization with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and analyze its correlation with acute graft-versus-host disease (aGVHD) and to understand the possible mechanisms underlying rhG-CSF-induced immune tolerance.

Methods

Sixty-eight healthy donor and their recipient pairs of family donor allogeneic hematopoietic stem cell transplantation (allo-HSCT) were included in this study. The expressions of chemokine receptors on CD4+ and CD8+ T cells in the peripheral blood (PB) before and after mobilization was detected using flow cytometry (FCM) respectively. Six chemokine receptors (CCR2, CCR5, CCR6, CCR7, CCR9 and CXCR3) were detected on T cell subsets in all the donors, and CCR5 and CCR7 were detected only in eighteen of all the donors. The expressions of chemokine receptor before and after mobilization was compared and its correlation with II-IV aGVHD were analyzed.

Results

After rhG-CSF mobilization, the expression of CCR9 on CD4+ T cells and CCR7 on CD8+ T cells were significantly upregulated compared with that before mobilization (p<0.05). However, the mean value of CCR5, CCR6 and CXCR3 expression on CD4+ and CD8+ T cell subsets in PB after mobilization didn’t differ significantly compared with that before mobilization(p>0.10). However, different individuals showed apparent inconsistencies. According to the changes of chemokine receptor expression on CD4+ and CD8+ T cell subsets, the evaluable donors and their relevant recipients were divided into the down-regulated group and the non-down-regulated (unchanged or up-regulated ) group. The incidence of grade II to IV aGVHD in the two groups were compared in their corresponding recipients. In the univariate analysis, mismatched HLA (p=0.046), down-regulation of CCR7 expression on donor CD4+ T cell subsets (p=0.010), unchangeableness or up-regulation of CCR5 expression on donor CD4+ T cell subsets (p=0.032) and CCR6 down-regulation on donor CD8+ T cells (p=0.045) were risk factors for recipients to develop II-IV aGVHD. In the multivariate analysis, down-regulation of CCR7 expression on donor CD4+ T cells after rhG-CSF was independent risk factor for II-IV aGVHD [RR=3.5, 95% CI (1.3-9.4), p=0.012], while CCR5 down-regulation on CD4+ T cells could reduce the incidence of II-IV aGVHD [RR=0.3, 95% CI (0.1-0.8), p=0.031].

Conclusions

rhG-CSF mobilization could lead to differential regulation of chemokine receptors expression on T cell subsets, which might cause different effects on the migration of T cells in vivo, and decrease T cells trafficking towards GVHD target organs, and thus reduce the incidence of aGVHD after transplantation.

Disclosures:

No relevant conflicts of interest to declare.
Allogeneic Stem Cell Transplantation In Philadelphia Negative Myeloproliferative Or Myelodysplastic/Myeloproliferative Neoplasms: A Retrospective Analysis From The Societe Française De Greffe De Moelle Et De Therapie Cellulaire (SFGM-TC)
Authors: Cahu Xavier , Chevallier Patrice , Clavert Aline , Suarez Felipe , Michallet Mauricette , Fegueux Nathalie , Vigouroux Stephane , Blaise Didier , Socié Gérard , Mariette Clara , Bilger Karin , Yakoub-Agha Ibrahim , Peffault de Latour Regis , Mohty Mohamad
Published: October 2019

Background

Philadelphia negative myeloproliferative or myeloproliferative/myelodysplastic neoplasms may evolve towards secondary acute myeloid leukemia (AML). The prognosis of such secondary leukemia is very poor. At present, there are only a few reports assessing the outcome of adult patients with a philadelphia negative myeloproliferative or myeloproliferative/myelodysplastic neoplasm in blast phase (MPN-BP) who received allogeneic stem cell transplantation (allo-SCT).

Patients and Methods

in this retrospective study, inclusion criteria were: (i) adult patients with a MPN-BP (ii) who received first allo-SCT (iii) between 2000 and 2010 (iv) irrespective of the stem cell source or conditioning regimen. MPN with <20% blasts in blood/bone marrow and AML secondary to myelodysplastic syndromes were excluded from this analysis.

Results

60 patients were included. MPN, AML and allo-SCT characteristics are described in table 1. Median age at allo-SCT was 57 (range, 30-68). Patients received allo-SCT in first complete remission (CR1), CR2 or in advanced disease in 22 (37%), 4 (7%) and 34(57%) of cases, respectively. Engraftment was achieved in 55 cases (92%). With a median follow-up of 31 months (range, 25-44), the 3-year overall survival (OS) and Leukemia-Free-Survival (LFS) were respectively 18% and 9%. The 3-year transplant-related mortality (TRM) was 24% whereas relapse incidence was 68%. The 3-year LFS of patients grafted in CR (n=26) was 18% whereas the 3-year LFS of patients allografted in advanced disease (n=34) was only 3% (p=0.008). In the CR group, the 3-year TRM was 24% whereas relapse incidence was 61%. Intermediate or good AML karyotype (3-year LFS of 33% versus 10% for adverse AML karyotype, p=0.03) and the absence of a previous thrombotic event (3-year LFS of 24% versus 0, p=0.02) were associated with an improved LFS in patients allografted in CR.

Conclusion

These results suggest that the outcome of patients with a MPN-BP is dismal despite allo-SCT due to a high relapse incidence even in patients transplanted in CR. Outside a clinical trial, allo-SCT should be mainly proposed to patients in CR. New strategies are mandatory to improve the outcome of patients in blast phase.

Disclosures:

No relevant conflicts of interest to declare.
Iron Chelation For Diseases Of Regional Siderosis
Authors: Cabantchik Zvi Ioav , Moreau Caroline , Devos David
Published: October 2019

The traditional role of iron chelation therapy has been the reduction of body iron burden via chelation of excess metal from organs and fluids and its excretion via biliary-fecal and/or urinary routes. While that approach is applicable to systemic iron overload, as seen in various forms of hemosiderosis, it might not be suited for treating disorders of iron maldistribution that are characterized by discrete islands of siderosis that appear in a context background of normal or subnormal iron levels (as in sideroblastic anemias, cardiosiderosis in Friedreich ataxia-FRDA and neurosiderosis in Parkinson’s disease-PD).

With the aim of clearing siderotic regions from labile (toxic) metal without interfering with essential local functions or with hematological iron-associated indices, we assessed here a conservative modality of iron chelation based on redeploying tissue chelated metal to physiological transferrin ( Sohn et al Blood 111:1690-9). As test redeployment agent we used deferiprone (DFP), a chelator with clinical proven record for correcting cardiac siderosis in systemic iron overload and in FRDA regional siderosis and for neuroprotection in a translational model of regional (brain) siderosis (that simulate key features of PD)( Moreau et al Am. J. Hematol. 2013;88:E5-E243). As part of a placebo-controlled randomized clinical trial of DFP in early stage PD patients (n=40) already stabilized with dopamine/dopaminergic regimens, we assessed whether a up to 18 month treatment (DFP 30 mg/kg/d in 2 daily syrup servings of Ferriprox) that significantly decreased substantia nigra-pars compacta siderosis (by T2* MRI) and showed neuro-functional benefits (UPDRS score), affected adversely hematological parameters. With the exception of 2 neutropenia patients that were withdrawn early in the trial (and resolved spontaneously) all others on DFP maintained steady plasma iron (80-115 ug/L), Tf- Sat (17-33%) hemoglobin levels (13.8-14.4 g/dL) and hematocrit (40-42 %) throughout the entire study, with just traces of daily sideruria but with serum ferritin that significantly dropped from 95±35 ng/ml to 30 ± 10 ng/ml during the first 12 months but not thereafter. We conclude that to the extent that iron chelation might have beneficial effects for treating neurodegenerative disorders that have a component of neurosiderosis, the modality of the DFP-based therapy provides a paradigm for treating regional siderosis without affecting hematological parameters. Supported by PHRC grants from the French Ministry of Research and the Adelina and Massimo DellaPergola Chair, HUJI, Jerusalem, Israel

Disclosures:

Cabantchik: Aferrix: Consultancy; Apopharma: invited speaker, invited speaker Other; Novartis: Speakers Bureau. Off Label Use: Deferiprone for Parkinson's Disease.
Heme Oxygenase 1 Plays a Role In The Pathophysiology Of β-Thalassemia
Authors: Santos Daniel Garcia , Mikhael Marc , Rivella Stefano , Horvathova Monika , Ponka Prem
Published: October 2019

Thalassemias are a heterogeneous group of red blood cell disorders ranging from a clinically severe phenotype requiring life-saving transfusions (thalassemia major) to a relatively moderate symptomatic disorder, sometimes requiring transfusions (thalassemia intermedia). Thalassemia minor, the least severe form of the disorder, is characterized by minimal to mild symptoms. While thalassemia minor and intermedia are vastly more prevalent than thalassemia major, the latter is often fatal when not treated. Though considered a major cause of morbidity and mortality worldwide, there is still no universally available cure for this severe form of thalassemia. A reason for this is at least in part due to the lack of full understanding of pathophsyiology of thalassemia. The underlying cause of pathology in thalassemia is the premature apoptotic destruction of erythroblasts causing ineffective erythropoeisis. Normally, the assembly of adult hemoglobin (consisting of a tetramer of two α- and two β-globin chains) features a very tight coordination of α- and β-globin chain synthesis. However, in β-thalassemia, β-globin synthesis is decelerated causing α-globin accumulation; while in α-thalassemia the opposite scenario occurs. Unpaired globin chains that accumulate in thalassemic erythroblasts are bound to heme. In addition, in β-thalassemia an erythroid specific protease destroys excess α-globin chains, likely leading to the generation of a pool of “free” heme in erythroblasts. “Free” heme is toxic, but this toxicity will likely be augmented, if heme oxygenase 1 (HO-1) can release iron from heme. To date, virtually no information about the expression of HO-1 in erythroblasts has been produced; however, we have recently provided unequivocal evidence that this enzyme is present in several model erythroid cells1. Based on this novel and important finding, we hypothesize that in β-thalassemic erythroblasts HO-1 mediated release of iron from heme is the major culprit responsible for cellular damage. To test this hypothesis we exploited the mouse model of β-thalassemia, th3/+. Thus far, our data indicates that HO-1 expression is increased in liver, spleen and kidney of β-thalassemic mice compared to wild type mice. Importantly, we observed that Epo-mediated erythroid differentiation of fetal liver (FL) cells isolated from β-thalassemic fetuses, display increased levels of HO-1 as well as decreased phosphorylated eiF2-α. These results indicate that β-thalassemic erythroblasts have inappropriately high levels of unbound heme that is continuously degraded by HO-1. Further research is needed to determine whether HO-1 liberated iron is responsible for the damage of β-thalassemic erythroblasts.

1Garcia Santos D, Schranzhofer M, Bogo Chies JA, Ponka P. Heme Oxygenase 1 plays an unexpected role during erythroid differentiation. Blood (ASH Annual Meeting Abstracts) 118: 344, 2011.

Disclosures:

No relevant conflicts of interest to declare.
Stop-Codon Mutation In The Extracellular Part Of G-CSFR Leading To G-CSF Unresponsiveness Due To Defects In Erk1/2 Phopsphorylation In a Patient With Severe Congenital Neutropenia
Authors: Klimenkova Olga , Zeidler Cornelia , Skokowa Julia , Welte Karl
Published: October 2019

We identified a 10 year old female severe congenital neutropnia patient who did not respond to the treatment with G-CSF (Filgrastim) up to 100 µg/kg/day, s.c. By search of possible reasons of G-CSF unresponsiveness, we detected by deep sequencing of the CSF3R (SOLID 5500xl, 3125 reads) a novel mutation within the extracellular part of CSF3R. The mutation was also confirmed by convential Sanger sequencing. It is a heterozygous stop-codon mutation C1641T (NM_000760), p.W547* (NP_000751) which is localized proximal to the cell membrane in the fifth fibronectin type III domain of the CSF3R. This is a first report describing a stop-codon mutation in the extracellular part of CSF3R in severe congenital neutropenia. FACS analysis revealed severely diminished surface expression levels of G-CSFR on CD33+ bone marrow myeloid progenitor cells of this patient as compared to G-CSFR levels on CD33+ cells of healthy individuals. In line with reduced expression of G-CSFR, we found disturbed G-CSFR-triggered intracellular signaling pathways activated by G-CSFR. MAPK/Erk1/2 activation by phosphorylation is known to be crucial for G-CSF- induced myeloid differentiation and STAT5 signaling is important for proliferation and survival of myeloid cells upon stimulation with G-CSF. We demonstrated abrogated phosphorylation of ERK1/2 and of STAT5 in bone marrow CD33+ myeloid cells of CN patient treated with G-CSF in vitro for 2, 5, 10 and 15 minutes, comparing with healthy donor. Since this patient has no known inherited CN-associated mutations (e.g. ELANE, HAX1, G6PC3), it may represent a new subgroup of CN patients characterized by non-responsiveness to G-CSF due to lack of binding of G-CSF to its receptor. Since the majority of investigations on CSF3R mutations are targeting the cytoplasmic part of the receptor only, we suggest that CN patients who do not respond to G-CSF treatment should be tested also for mutations within the extracellular part of the CSF3R.

Disclosures:

No relevant conflicts of interest to declare.
Ratios Of FcγRIIa and FcγRIII Binding Affinities Govern The Efficacy Of PMN-Mediated Cytotoxicity – Implications For Fc-Engineering Approaches Of Therapeutic Antibodies
Authors: Derer Stefanie , Glorius Pia , Schlaeth Martin , Lohse Stefan , Muchhal Umesh , Desjarlais John , Humpe Andreas , Valerius Thomas , Peipp Matthias
Published: October 2019

Introduction

Antibody-dependent cell-mediated cytotoxicity (ADCC) has been suggested to be an essential effector mechanism for the in vivo activity of tumor-targeting therapeutic monoclonal antibodies (mAbs). Thus, enhancing the affinity of human IgG1 mAbs to NK cell-expressed FcγRIIIa by glyco- or protein-engineering of their Fc moiety has been demonstrated to improve NK cell-mediated ADCC and represents a promising strategy to improve antibody therapy. However, human polymorphonuclear (PMN) cells express the homologous FcγRIIIb isoform, which does not trigger ADCC. The aim of the present study was to analyze a panel of distinct IgG1 mAbs, displaying different affinities for FcγRIIa and FcγRIII, with respect to PMN recruitment for tumor cell destruction.

Methods

Affinities of analyzed mAbs to distinct FcγR were determined by surface plasmon resonance technology. Induction of ADCC was assessed by 51Cr release experiments in the absence or presence of FcγRIII- or FcγRII-blocking agents to unravel the contribution of both receptors in these assays.

Results

Non-fucosylated or protein-engineered IgG1 variants with optimized FcγRIII binding capacities demonstrated the expected benefit in triggering NK cell- mediated ADCC but did not mediate ADCC by PMN, which could be restored by FcγRIIIb blockade. Additionally, eosinophils as well as PMN from paroxysmal nocturnal hemoglobinuria (PNH) patients – expressing no or low levels of FcgRIIIb – mediated effective ADCC with FcgRIII-optimized mAbs. Additional experiments with Fc variants displaying enhanced FcγRIIa binding or with double FcγRIIa/FcγRIII-optimized constructs demonstrated enhanced PMN-mediated ADCC compared to control mAbs. Statistical analyses revealed that FcγRIIa/FcγRIIIb affinity ratios correlated with the extent of human PMN-mediated ADCC.

Conclusions

To conclude, the present study represents novel findings concerning recruitment of PMN for tumor cell destruction by Fc-engineered antibodies. While PMN-mediated ADCC was completely abolished by FcγRIII-optimized antibodies through predominant FcγRIIIb binding, it was potently enhanced by optimization of FcγRIIa binding affinity. Importantly, functional analyses unraveled the ratio between FcγRIIa and FcγRIII binding affinities to control PMN-mediated ADCC activity and therefore opened new alleys in engineering of therapeutic antibodies.

Disclosures:

Muchhal: Xencor Inc.: Employment. Desjarlais:Xencor Inc.: Employment.
Identification Of Factors That Can Predict a Response To Intravenous Immunoglobulin Treatment In Children With Immune Thrombocytopenic Purpura
Authors: Yoshida Nao , Morimoto Yoshihito , Kawashima Nozomu , Matsumoto Kimikazu , Kato Koji
Published: October 2019

Immune thrombocytopenic purpura (ITP) is a common benign bleeding disorder characterized by isolated thrombocytopenia caused by the immune-mediated destruction of platelets. The 2004 Japanese Guidelines for Childhood ITP recommended intravenous immunoglobulin (IVIG) as first-line therapy for children with ITP, because this strategy results in more rapid increases in platelet counts when compared with oral steroid therapy. However, predictive markers of the response to IVIG have not been well defined. The present study therefore evaluated whether clinical and laboratory findings before treatment could predict the response to IVIG and progression to chronic ITP.

We reviewed the clinical data of 49 newly diagnosed patients (< 18 years) with ITP who were given IVIG as initial treatment at Japanese Red Cross Nagoya First Hospital from 1997 to 2011, and evaluated the short-term response to IVIG as outcomes at 2 weeks after IVIG and the long-term response to IVIG as thrombocytopenia-free survival (TFS). TFS was defined as the probability of survival without treatment failure (death, relapse, disease progression requiring other therapeutic intervention, or progression to chronic ITP) after initial IVIG and was estimated by the Kaplan-Meier method.

Short-term response to IVIG was observed in 40 patients (82%), and long-term treatment response, defined as 1-year TFS, was 65%. At 6 months after initial IVIG treatment, seven patients (14%) progressed to chronic ITP. In multivariate analysis, lower white blood cell (WBC) count at diagnosis was identified as the only independent risk factor for the short- or long-term response to IVIG (P=0.007 or P=0.043, respectively) and the progression to chronic ITP (P=0.034). Patients with WBC count<7.0×109/L had a lower probability of TFS (41% vs. 77%, P=0.003) and a higher rate of progression to chronic ITP (29% vs. 6%, P=0.040) than those with WBC count ≥7.0×109/L. None of the other variables, including gender, age at diagnosis, season of onset, initial platelet count, initial hemoglobin level, preceding infection, fever at diagnosis, H. pylori infection, total and daily dose of IVIG, product of IVIG, and laboratory findings including CRP, TP, T-bil, LDH, AST, ALT or BUN, were significantly associated with the response to IVIG and the progression to chronic ITP in multivariate analysis.

In conclusion, this study showed that WBC count at onset of ITP is a strong predictor of short- and long-term treatment response to IVIG and the development of chronic ITP in pediatric patients with ITP. For patients with low WBC count, the addition of other agents, such as steroids, to IVIG at the time of initial diagnosis might improve the treatment outcomes.

Disclosures:

No relevant conflicts of interest to declare.