bluuebunny/crossref_metadata_2025 huggingface dataset:
Statin Use Improves Overall Survival and Time to Treatment Failure in Patients with Primary CNS Lymphoma.
Authors: Ciminello Lauren , Toomey Christiana , Cobert Julien , Hochberg Fred H , Abramson Jeremy S. , Hochberg Ephraim
Published: October 2019

Abstract 2496

Poster Board II-473

Background:

HMG-CoA reductase inhibitors (statins) have been used to treat hypercholesterolemia and hyperlipidemia for over 20 years. Statins competitively inhibit HMG-CoA reductase thereby blocking the synthesis of mevalonate. They directly inhibit synthesis of steroid hormones and cholesterol but also indirectly inhibit prenylation and ubiqitination. As all currently marketed statins are lipophillic, with the exception of Pravachol (pravastatin), several therapeutic trials have attempted to exploit these indirect actions to treat both neoplastic (glioblastoma, anaplastic astrocytoma) and degenerative (Alzheimer's, Parkinson's) neurologic disease. We studied the impact of incidentally prescribed statins on high-risk patients with primary central nervous system diffuse large B cell lymphoma (PCNSL).

Methods:

We used an IRB-approved clinicopathologic database, derived from comprehensive tumor registry data at the Massachusetts General Hospital, to identify all patients diagnosed with primary central nervous system lymphoma (PCNSL) between 1991 and 2007 (n=118). We excluded pediatric patients, patients who did not receive curative treatment and patients who failed to achieve a CR with initial therapy. Automated analysis of billing and medication administration records was used to identify the administration of statins to these patients. We compared the outcome of patients who were receiving statins to controls with PCNSL who did not receive statins. We excluded patients who did not receive statins within the time interval from 6 months prior to 2 years after their PCNSL diagnosis. As only a single statin pt was less than 50 we excluded all pts below this age from the cases and controls. All patients received high dose MTX based therapy. Overall survival (OS) was calculated from the date of first methotrexate.

Results:

Median age of statin patients was 66 yrs (range 52 – 76); median age of controls was 66 years (range 50 - 86). Nine patients were on atorvastatin, 9 were on simvastatin, 1 each were on pravastatin, rosuvastatin and fluvastatin. At a median follow-up of 47.5 months, concurrent statin therapy was associated with improved OS (62% vs. 37%)(p=0.04 Log-rank test). The median OS for all statin patients > 50 years old (n=21) was 60 months versus 37 months for all other patients > 50 years old (n=67) (p=<0.005 t-test two tailed).

Conclusions:

Concurrent prescription of HMG-CoA reductase inhibitors is associated with improved outcome in patients with high risk PCNSL compared to controls. Prospective controlled trials will be required to validate this observation.

Disclosures:

Hochberg: Amgen: Speakers Bureau; Biogen-Idec: Speakers Bureau; Genentech: Speakers Bureau; Enzon: Speakers Bureau.
Treatment Does Not Correlate with Quality of Life in Children with Immune Thrombocytopenic Purpura: Results From the KIT International Cross-Cultural Validation Study.
Authors: Klaassen Robert , Grainger John D. , Riedlinger Arne , Blanchette Victor S. , Burke Tricia , Citrin Estela , Alvarez Gustavo Dufort y , Rachieru Petronella , Rakotonjanahary Josué , Gaedicke Gerhard , Wakefield Cindy D. , Young Nancy L.
Published: October 2019

Abstract 2501

Poster Board II-478

Introduction:

There is considerable controversy surrounding whether or not children with Immune Thrombocytopenic Purpura (ITP) should be treated if they present without bleeding. One of the potential benefits of treatment would be to improve the child's health-related quality of life (HRQoL).

Patients and Methods:

Variables including age, sex, type of ITP(acute versus chronic), treatment (observation, IVIG, Anti-D, and prednisone), platelet count and country of origin were analysed by multiple regression to determine their relationship to HRQoL as measured by the Kid's ITP Tools (KIT) child self-report version.

Results:

77 children from Uruguay (n=15), France (n=25), Germany (n=13) and the UK (n=24) self-completed the KIT. Mean platelet counts were: 6 for acute ITP patients (mean age 8.6 yrs) and 30 for chronic patients (mean age of 10.8 years). KIT scores by type of ITP and country are shown in the Figure. Multiple regression found that only the type of ITP (p=0.04) and the country of origin (p=0.029) were significantly associated with the KIT scores. Age, sex, platelet count and treatment were not correlated with KIT scores (p>0.16).

Conclusion:

The method of treatment did not have a significant impact on child-reported HRQoL. However, differences in HRQoL scores were found between acute and chronic groups and by country of origin.

Disclosures:

Klaassen: Cangene : Research Funding. Blanchette:Cangene: Research Funding. Young:Cangene: Research Funding.
Conditional Knockout of Sox4 Markedly Affects B Lymphopoiesis in Adult Mice.
Authors: Sun Baohua , Mallampati Saradhi , Gong Yun , Wang Donghai , You M. James , Amin Hesham M. , Ma Yupo , Rajewsky Klaus , Lefebvre Veronique , Sun Xiaoping
Published: October 2019

Abstract 2524

Poster Board II-501

B cells constitute an integral part of the immune system. The development of mature B cells from hematopoietic stem cells is a complex process that is regulated in a hierarchical order by various proteins, particularly transcription factors. Sox4 is a SRY-related HMG box containing transcription factor and is known to be involved in B cell development. However, the role of Sox4 in various stages of B cell development has not been systematically investigated. In this study we used a conditional knockout mouse strain and studied the effect of Sox4 deletion in B lymphopoiesis in adult mice. We crossed the Sox4-floxed mice with different Cre mouse strains that were expected to delete the floxed Sox4 gene at different B cell developmental stages. These Cre strains included Vav-iCre (expressed in hematopoietic stem cell stage, starting from early embryos), MX1-Cre (expression in hematopoietic stem cells, induced by pIpC injection in adults), MB1-Cre (expressed in B cells, starting from early progenitor cells in embryos), and CD21-Cre (expressed in mature B cells). We demonstrated that deletion of Sox4 caused an arrest of B lymphopoiesis at the transition from pre-pro-B cell (fraction A) stage to pro-B cell stage (fraction B): fraction A cells are slightly reduced in number whereas fraction B and later stage cells are nearly absent. The pre-pro-B cells from the Sox4 knockout mice retain a population of AA4.1+ cells, which are considered to be developed into B cells. Deletion of Sox4 in early embryonic stage (Vav-iCre) or in adults (Mx1-Cre) results in a similar phenotype on B lymphopoiesis, except that peritoneal B1 cells appear to be affected with Vav-iCre, but not with Mx1-Cre. MB1-Cre gave rise to similar results as did Vav-iCre, but the arrest was not as dramatic as with Vav-iCre. CD21-Cre produced no significant difference in B cell phenotype. These data suggested that Sox4 is required for early B cell development at the transition from pre-pro-B cells to pro-B cells and is not required for mature B cells. We are currently investigating the transcription program of this transcription factor in B cell development.

Disclosures:

No relevant conflicts of interest to declare.
A Recessive Embryonic Screen for Genes Regulating Hematopoietic Stem Cell and Blood Cell Generation and Function.
Authors: Papathanasiou Peter , Tunningley Robert , Pattabiraman Diwakar Ram , Ye Ping , Gonda Thomas J , Perkins Andrew Charles
Published: October 2019

Abstract 2527

Poster Board II-504

Identifying the genes that regulate the development, self-renewal and differentiation of stem cells is of vital importance for understanding normal organogenesis, tailoring tissue engineering for regenerative medicine, cellular reprogramming and cancer. A forward genetic screen for aberrant long-term hematopoietic stem cells and progenitors provides an unbiased and tractable approach to finding genes responsible for stem cell homeostasis and differentiation. Here we demonstrate that chemical mutagenesis of mice combined with advances in hematopoietic stem cell reagents and genome/mapping resources can identify genes essential for mammalian stem cells and blood development. A pilot flow cytometry-based recessive screen comprehensively analyzed nine subsets of hematopoietic stem, progenitor, and red cells in over one thousand mouse embryos at embryonic day (E) 14.5 from 34 pedigrees and recovered five strains with defects in early hematopoiesis. One mutant strain (Booreana - an Australian Aboriginal name meaning white) which has excess long-term hematopoietic stem cells and platelets but reduced myelo-erythroid progenitors was outcrossed and the genetic mutation mapped and identified as a novel mis-sense mutation in the transcription factor c-Myb. The mutation in the trans-activation domain (TA) completely ablates transcriptional activation in a reporter assay which contrasts with other TA domain mutants which are partly dysfunctional[TJG1] . Moreover, the Booreana (Boo) mutation completely abrogates interaction with the transcriptional co-activator, CBP. Boo/Boo homozygous mutant mice survive into adulthood, albeit with severe anemia and massively increased platelet counts, whereas c-Myb−/− mice die by E15.5 of development, suggesting c-Myb has essential functions in vivo which are independent of transcriptional activation. This ENU-generated mutation provides another allele of c-Myb with a phenotype in between the complete loss-of-function allele and previously identified mutant alleles from other ENU screens. ENU-generated point mutants such as the Booreana mutation can provide novel informative insights into key functional domains of proteins, and protein interactions and networks, which are missed in gene knockout mice. Other phenodeviants generated in our screen are currently being mapped and will be presented.

[TJG1]Not so in our hands, at least -– the Sandberg M303V is just as dead.

Disclosures:

No relevant conflicts of interest to declare.
Brain Imaginig in SCD Adults Patients: Correlation to TCD Image and Atoxic Contrast ( Microbubbles).
Authors: Bahia Paulo , Leite Ana , Veloso Orlando , Lobo Clarisse LOPES , Marcondes Jorge
Published: October 2019

Abstract 2555

Poster Board II-532

The purposes of this study were to evaluate the intracranial lesions in adults patients with sickle cell disease (SCD) using magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). The patients were selected from the main hematological hospital of Rio de Janeiro state (HEMORIO). About 187 patients underwent neurological examination and Transcranial Doppler image (TCDi) with microbubbles. Eighty patients were chosen by an aleatory way to perform MRI and MRA, including those symptomatic and asymptomatic ones. MRI and the MRA were evaluated by two different neuroradiologists, in a blind way about the clinical aspects and TCD results. The middle age was 29 years and 81.3% of the patients had the homozygous form of the SCD. In the MRI, 50% of the patients showed intraparenchymatous lesions. Leukoencephalopathy was the most frequent abnormality in 47.5%, encephalomalacia in 16%, lacunar infarctation in 12.5% and atrophy in 12.5%. Of the encephalomalacia cases, the frontal and parietal lobes were the most affected in 85%. In the MRA study, 34% of the patients presented abnormalities, 26% with vascular stenosis and 19% with vascular occlusions. The anterior circulation was the most compromised in the stenotic cases and the carotid was the main affected artery in the occlusions cases. The silent lesions were observed in 45% of the MRI and 24% of the MRA. The prevalence of parenchymatous lesions and vascular stenosis in cases with genotype SS was significant. There was significant statistic relation between the leukoencefalophalopathy and the vascular stenosis with the medium basal hematocrit.

CONCLUSIONS:

The use of both methods (MRI and TCD image) demonstrated a powerful tool to study vascular lesions in SCD adults patients. The prevalence of silent infarcts in SCD adults patients was higher than previously estimated in literature (55%). This finding reinforces the prophylactic intervention study with TCD Imagining and prophylactic transfusion therapy in early stage of life.

Disclosures:

No relevant conflicts of interest to declare.
Relapsed Childhood High Hyperdiploid Acute Lymphoblastic Leukemia: Genome-Wide Screening Reveals the Presence of Preleukemic Ancestral Clones and the Secondary Nature of Microdeletions and RTK-RAS Mutations.
Authors: Davidsson Josef , Paulsson Kajsa , Lindgren David , Lilljebjörn Henrik , Chaplin Tracy , Forestier Erik , Andersen Mette K , Nordgren Ann , Rosenquist Richard , Fioretos Thoas , Young Bryan D , Johansson Bertil
Published: October 2019

Abstract 2591

Poster Board II-567

Although childhood high hyperdiploid acute lymphoblastic leukemia is associated with a favorable outcome, 20% relapse. This makes it important to identify these patients already at diagnosis to ensure proper risk-stratification. To identify changes associated with relapse and ascertain the genetic evolution patterns, SNP array and mutation analyses of FLT3, KRAS, NRAS, and PTPN11 were performed on 11 paired diagnostic/relapse samples. The “triples trisomies” +4, +10, and +17 were detected in 64%, a frequency similar to the one generally observed at diagnosis, thus questioning their favorable prognostic impact. Structural changes, mainly cryptic hemizygous deletions, were significantly more common at relapse (P<0.05). No single aberration was linked to relapse, but four deletions, involving IKZF1, PAX5, CDKN2A/B or AK3, were recurrent. Based on the genetic relationship between the paired samples, three groups were delineated: 1) identical genetic changes at diagnosis and relapse (18%), 2) clonal evolution with all changes at diagnosis being present at relapse (18%), and 3) clonal evolution with some changes conserved, lost or gained (64%), suggesting the presence of a preleukemic clone. This ancestral clone was characterized by numerical changes only, with structural changes and RTK-RAS mutations being secondary to the high hyperdiploid pattern and perhaps necessary for overt leukemia.

Disclosures:

No relevant conflicts of interest to declare.
The AML Prognostic Marker, AF1q, Is Directly Regulated by MiR-29b.
Authors: Xiong Yin , Li Zejuan , Tan Aik Choon , Bemis Judson , Xie Xiuyan , Bunting Kevin D. , Chen Jianjun , Bemis Lynne , Tse William
Published: October 2019

Abstract 2603

Poster Board II-579

We have consistently shown that elevated expression of AF1q, an MLL fusion partner, is a poor prognostic biomarker for pediatric acute myeloid leukemia (AML), adult AML with normal cytogenetics (NC-AML), and adult myelodysplastic syndrome (MDS). However, the underlying mechanism of how AF1q is regulated in normal and abnormal hematopoiesis is still unclear. Our previous studies suggest that AF1q is highly regulated during hematopoietic cell differentiation and development and it is known that genes related to cell development and differentiation are likely to be regulated by various microRNAs. We used a variety of the web based programs to identify microRNA candidates that may potentially regulate AF1q based on the predicted targeting efficiency. We found the strongest predicted binder to the AF1q 3′untranslated region (3′UTR) was miR-29b, a member of the miR-29 family which has recently been characterized to regulate a member of the Bcl-2 family protein, Mcl-1 and other leukemia related oncogenes. We found that MiR-29b expression had a significantly inverse correlation (p<0.05) with AF1q expression in a cohort of more than 60 AML patients. This relationship is consistent with microRNA/AF1q regulation. In order to determine if miR-29b directly regulates AF1q, we chose H157 and SKMES1 lung cancer cell lines which were known to have high AF1q expression and high transfection efficiency to test if transfection of miR-29b into cells can suppress its endogenous AF1q expression. Our data showed that transfection of miR-29b into these two cell lines could indeed significantly suppress the AF1q expression both in H157 (p=0.001) and SKMES1 (p=0.004) cells. Then we wanted to determine if the miR-29b binding domain is specific in the AF1q 3′UTR region. Two reporter plasmids that contained the germline AF1q 3'UTR (GFP-A3U) and mutant AF1q 3′UTR in its microRNA binding site (GFP-A3U-Mutant) were constructed. We found that GFP readout was significantly suppressed in a stable transfection with native AF1q 3′UTR (GFP-A3U); in contrast, the GFP readout was not suppressed in a stable transfection with GFP-A3U-Mutant, suggesting that miR-29b is able to bind to the germline AF1q 3′UTR but not to the mutated 3′UTR (GFP-A3U-Mutant). These observations proved that miR-29b specifically regulates AF1q expression through its binding to the AF1q 3′UTR. Taking these observations together, we conclude that miR-29b directly regulates the leukemia associated gene AF1q. Elevated AF1q expression was found to have clinical significance in AML, thus, these findings warrant further investigation to determine if miR-29b will be able to serve as a prognostic biomarker for AML patients.

Disclosures:

No relevant conflicts of interest to declare.
Correlation of Altered Expression of RIZ1 to Diagnosis, Risk Stratification, and Disease Progression in 56 Acute Leukemia Patients.
Authors: Li Qiubai , Zhu Xiaojian , Li Xiaoqing , Chen Xiangjun , You Yong , Huang Shi , Huang Shiang , Zou Ping , Chen Zhichao
Published: October 2019

Abstract 2627

Poster Board II-603

RIZ1 expression is altered in a variety of human cancers and is now considered to be a candidate tumor suppressor in many types of human tumors, including breast cancer, liver cancer, colon cancer, neuroblastoma, melanoma, lung cancer, and osteosarcoma. Previous studies indicate that suppression of RIZ1 expression may have an important role in leukemogenesis and RIZ1 is downregulated during CML progression and displays tumor suppressor properties in CML cell lines. To deeply investigate the expression of RIZ1 and its correlation to diagnosis, risk stratification, and disease progression in human acute leukemia, we analysed the differential expression of RIZ1 by quantitative real-time reverse-transcription polymerase chain reaction assay in 56 acute patients with or without complete remission and in 9 healthy donors. Our results showed that the expression of RIZ1 was significantly decreased in both de novo acute leukemia patients and patients with no remission (n = 35) (P = 0.009, compared with healthy donors) and significantly increased in acute leukemia patients with complete remission (P = 0.001, compared with de novo acute leukemia patients and patients with no remission). When compared with healthy donors, acute leukemia patients with complete remission (n = 21) owned the statistically same expression of RIZ1 (P = 0.595). The expression of RIZ1 was significantly higher in acute myeloid leukemia (AML, n = 17) than acute lymphoblastic leukemia (ALL, n =15) (P = 0.009), with a good correlation to diagnosis of AML or ALL (r = 0.514). The patients (n = 16) with high-risk leukemia had significantly higher expression of RIZ1 than the patients with standard-risk (n = 18) (P = 0.031), with the correlation (r = 0.431) of RIZ1 expression to disease risk-stratification. In addition, the weak correlations of RIZ1 expression were shown to both age and gender ( r = 0.158 and 0.003, respectively). This relatively simple analysis provides an important role of RIZ1 expression in acute leukemia. Taken together, our results suggest the potential for using RIZ1 expression in predication of disease progression or recovery in acute leukemia. We demonstrate that RIZ1 expression can contribute to the diagnosis of AML or ALL and the evaluation of risk-stratification in acute leukemia.

Disclosures:

No relevant conflicts of interest to declare.
Glucocorticoid-Induced TNFR-Related Protein (GITR) Ligand Mediates Tumor Immunoediting in Chronic Lymphocytic Leukemia and Impairs Direct and Rituximab-Induced NK Cell Anti-Leukemia Reactivity.
Authors: Buechele Corina , Baessler Tina , Schmiedel Benjamin J , Kanz Lothar , Salih Helmut R
Published: October 2019

Abstract 4403

Members of the TNF/TNF receptor (TNFR) family of proteins govern differentiation, proliferation, activation, and death of both tumor and immune effector cells and thus play an important role in tumor immunoediting, the reciprocal interaction of tumor cells and anti-tumor immunity. Activation of the TNFR family member GITR has recently been shown to stimulate T cell-mediated anti-tumor immunity in mice. However, available data suggest that GITR mediates different effects in mice and men, and may impair anti-tumor immunity of human NK cells. Here we studied the expression and function of GITR ligand (GITRL) in patients with chronic lymphocytic leukemia (CLL) and the consequences of GITR-GITRL interaction for NK cell reactivity against CLL cells. Substantial GITRL expression was detected on primary B-CLL cells in 38 of 48 (79%) investigated patients. Upon interaction with its cognate receptor, GITRL induced the release of immunoregulatory cytokines like TNF by the leukemia cells, which demonstrated that CLL-expressed GITRL is functional and capable to transduce bidirectional signals. Moreover, disruption of GITR-GITRL interaction in cultures of allogenic NK cells with patient CLL cells by addition of blocking antibody caused a significant increase in NK cell granule mobilization, cytotoxicity and IFN-γ production. The inhibitory effect of tumor-expressed GITRL on the reactivity of human NK cells was also confirmed in cocultures of C1R lymphoma cells transfected to express GITRL with mock transfectants serving as control. In addition, blocking GITR-GITRL interaction also considerably augmented both antibody-dependent cellular cytotoxicity (ADCC) and antibody-induced IFN-γ production of NK cells in cultures with allogenic CLL cells upon Rituximab exposure. Of note, GITR blockade also significantly enhanced anti-leukemia reactivity of autologous NK cells among PBMC of B-CLL patients, and this reinforcement of NK cell effector functions was observed both regarding the direct and, more pronounced, Rituximab-induced anti-leukemia reactivity (both n=10, p<0.01, Student's T test). Thus, expression of functional GITRL by CLL cells potently influences tumor immunoediting and impairs anti-tumor immunity by diminishing both direct and Rituximab-dependent anti-leukemia reactivity of NK cells. Modulation of the GITR-GITRL system might therefore serve to enhance the efficacy of therapeutic approaches in CLL which, like Rituximab-induced ADCC or stem cell transplantation, rely on a sufficient NK cell anti-tumor response.

Disclosures:

No relevant conflicts of interest to declare.
Lymphoplasmacytic Differentiation Associated with Lenalidomide Therapy in Patients with Chronic Lymphocytic Leukemia.
Authors: Veliz Marays , Moscinski Lynn C. , Zhang Ling , Sotomayor Eduardo M. , Pinilla-Ibarz Javier
Published: October 2019

Abstract 4412

Background

Due to significant activity of lenalidomide in chronic lymphocytic leukemia (CLL), research is ongoing to better characterize its mechanism of action. Recent laboratory studies of cells from CLL patients have shown that lenalidomide could exert its antiproliferative activity by decreasing the presence of survival-promoting cytokines. It has also been shown to facilitate immune-mediated ADCC by restoring the defective ability of T- and NK-cells to form immune synapses with tumor B-cells (Ramsay et al JCI 2008). However, no direct cytotoxic effect of lenalidomide has yet been demonstrated in CLL cells. Here, we suggest a new potential mechanism of action based on morphologic evaluation of bone marrow samples from patients with CLL receiving treatment with lenalidomide.

Methods

Bone marrow biopsy and aspirations from 13 patients with relapsed or refractory CLL, who are participating in a phase II clinical trial of lenalidomide and rituximab, and 1 patient who received lenalidomide outside of study, were reviewed before initiation of therapy and every 2 months thereafter.

Results

Of 14 CLL samples evaluated, 3 samples contained cells with lymphoplasmacytoid features in both bone marrow (figure 1) and peripheral blood, which had not been present prior to initiation of treatment. Of the 3 samples containing lymphocytes with plasmacytoid features, 2 were obtained from patients who received more than 6 months of therapy with the lenalidomide/rituximab combination, and 1 was taken from the patient receiving lenalidomide, after one month of therapy. Long term morphologic effects of lenalidomide therapy on lymphocytes from patients with CLL remain unknown. However, we hypothesize that the observed changes in morphology after lenalidomide treatment could represent either a differentiation phenomenon, as a potential antitumor mechanism in CLL cells, or perhaps represent just a selection effect.

Conclusions

An exact direct antitumor mechanism of lenalidomide on CLL cells remains unknown. Our observations suggest that lenalidomide may promote terminal differentiation of lymphocytes thus proposing an additional mechanism by which lenalidomide exerts its anti-tumor activity in CLL.

Disclosures:

No relevant conflicts of interest to declare.
IL-27 Induced Apoptosis and Promoted Antitumor Cytokines Secretion in Human Monocytic Leukemic Cell Line U937.
Authors: Liu Bin-Bin , Fan Rui-Fang , Zheng Yong-Jiang , Guo Xiao-Yan , Lin Dong-Jun
Published: October 2019

Abstract 4418

IL-27 acts as a critical regulator in many pathological processes. Although IL-27 has been studied in many solid tumors, its effect on leukemia remains elusive. Here, we investigated expression of IL-27 receptor (WSX-1 and gp130) on bone marrow mononuclear cells (BM-MNCs) of 31 patients with acute myeloid leukemia (AML) and 8 controls (including patients with IDA, ITP and non-hematological diseases) by RT-PCR, exploring IL-27's property in malignant hematological diseases. In addition, we detected the secretion of antitumor cytokines, cell proliferation and apoptosis in human monocytic leukemic cellline (U397 cells) treated with IL-27. We found that expression rate of IL-27 receptor subunits in AML patients was significantly higher than those with benign hematological diseases, especially on the acute monocytic leukemia subtype (AML-M5 subtype). ELISA assay revealed that antitumor cytokines, including TNF-α and IL-12, were produced by IL-27 stimulated-U937 cells, with an optimal concentration of IL-27 at 60ng/mL and an optimal time at 24h. U937 cells' growth inhibition and apparent apoptosis was induced by IL-27 in a dose dependent manner. U937 cells displayed apparent apoptosis when treated by IL-27 over 40ng/ml. The apoptosis rate of U937 tumor cells reached peak level while the stimulation concentration was 100ng/ml. Hoechst 33258 staining also presented typical apoptotic bodies in U937 cells treated with IL-27. Based on the high expression of IL-27 receptor in BM-MNCs of AML patients, our data provided the first evidence that IL-27 functioned as an anti-leukemia cytokine, suppressing cell growth and inducing apoptosis, offering a new anticancer agent in leukemia therapy.

Disclosures:

No relevant conflicts of interest to declare.
Prognostic Significance of Gelsolin and MMP12 in Langerhans Cell Histiocytosis.
Authors: Kim Sun Young , Kim Hee Jin , Bae Keun Wook , Im Ho Joon , Kim Ji Yoon , Jeong Dae-Chul , Lee Mee Jeong , Park Eun Sil , Seo Jong Jin
Published: October 2019

Abstract 4431

Background

Langerhans cell histiocytosis (LCH) pathogenesis is hypothesized a genetic change may have a significant effect on the cellular mechanisms controlling proliferation and apoptosis of LCs. In LCH, the expression of MMP12 was observed most abundantly in multi-system disease, which has the poor prognosis, and high expression of GSN was reported but the clinical significance of GSN was unveiled until now. We will investigate the association between these proteins and clinical outcomes in patients diagnosed with LCH.

Methods

Archival paraffin block were retrieved from children diagnosed with LCH and followed up at Asan medical center and Chungnam National University Hospital between 1998 and 2008. Available formalin-fixed, paraffin-embedded specimens from these patients will be used for GSN, MMP12 immunohistochemistry. We will analyze the correlations between protein expression states and clinical features.

Results

The medical records of the patients with LCH was analyzed for the factors that affect relapse and overall survival. The specimens from 49 patients were available for immunohistochemistry. Of these, 2 slides were not suitable because the quality of staining was not good for evaluation or the tumor cells are too difficult to be differentiated. The median age of 49 patients was 9.5 years, range 5 months to 22 years with a definite diagnosis of LCH based on CD1a positivity. The gelsolin and MMP12 were expressed in various degrees except eight specimens and overexpression had a tendency of correlation with multisystem and risk organ involvement.

Conclusion

Gelsoin and MMP12 might be associated with the pathogenesis of LCH and the high expressions in LCH have a possibility of playing a role in the progression of LCH.

Disclosures:

No relevant conflicts of interest to declare.
Safety and Efficacy of Plasma Derived Factor IX in Patients with Hemophilia B Undergoing Surgical Intervention: A Single Institution, Retrospective Analysis.
Authors: Logan Laurence , Quon Doris V.
Published: October 2019

Abstract 4438

Introduction

Hemophilia B patients often require orthopedic surgical intervention for the improvement of function and quality of life. In these patients, coagulation factor replacement is essential, but the safety and efficacy of plasma-derived factor IX in controlling bleeding during surgeries has been little studied. Issues of particular concern for surgical intervention include appropriate dosing of factor concentrate, pharmacokinetics, and safety considerations.

Objective

The purpose of this study was to examine outcomes in patients with hemophilia B following surgical intervention and treatment with plasma-derived factor IX.

Method

Following IRB approval, 22 patients who underwent 31 surgical procedures at the Hemophilia Treatment Center at Orthopedic Hospital or its affiliates in Los Angeles, CA, during the period 1996 to present, were identified. Once identified, inpatient charts for these patients were reviewed and abstracted. Outcomes of interest included pre- and post operative dosing of factor IX, perioperative blood loss and use of blood products, pharmacokinetics factors, and hemostatic response.

Results

For identified patients, 9.1% were diagnosed with mild hemophilia B (factor IX levels > 5%), 13.6% had moderate hemophilia B (factor IX levels between 1% - 5%), and 77.3% had severe hemophilia B (factor IX < 1%). The mean age at surgery was 48.0 years old. All but 3 surgical procedures were orthopedic (90.3%) and most frequently involved the knee (38.7%), elbow (16.1%), hip (12.9%), or shoulder (9.6%). All surgeries were completed under general anesthesia and average time in surgery was 3:15 hours. Dose of factor IX averaged 238 IU/kg on the day of surgery and was adjusted over the course of the hospital stay. Selection of replacement factor IX was by patient choice and AlphaNine® SD was the most common factor IX concentrate used (94% of procedures). Mean perioperative blood loss was 283ccs (range 0-1000) and blood replacement was required in only 2 surgeries (6.5%). Pharmacokinetic analysis performed pre-operatively related well to factor IX levels obtained peri- and post-operatively. Average hospital length of stay was 10.7 days and all patients were discharged to home.

Conclusion

The results of this study demonstrated that patients with Hemophilia B undergoing major surgery who were treated with plasma derived factor IX had little unexpected blood loss perioperatively, seldom required blood replacement, and had no bleeding related surgical complications. These results suggest that pre- and postoperative treatment with plasma derived factor IX is both safe and effective for patients with hemophilia B undergoing surgical intervention.

Disclosures:

Logan: Grifols, S.A.: Consultancy. Quon:NovoNordisk: Speakers Bureau; Grifols, S.A.: Honoraria.
FactorVIII Gene Modifications Observed in Acquired Hemophilia.
Authors: Hwang Sung Ho , Kim Hugh C , Lim Jeonga , Lee Hyun Woo , Jeong Seong Hyun , Park Joon Seong , Kim Hye Sun
Published: October 2019

Abstract 4450

Acquired hemophilia is a rare bleeding disorder caused by autoantibodies directed against the coagulation factor VIII (FVIII). Usually acquired hemophilia is found in the elderly person, autoimmune disorder or women in the postpartum. Incontrast to alloantibody inhibitors of hereditary hemophilia, acquired inhibitor is presumably due to a spontaneous autoimmune disorder in which patients with previously normal hemostasis develop autoantibodies against FVIII. However, the precise cause of the antibody formation remains obscure and the possibility of abnormal FVIII protein derived from the FVIII gene mutation might have caused the antibody formation was investigated by direct FVIII gene sequencing method. Blood samples were obtained from a 72 year old male who initially presented with a large hematoma in the Rt. Shoulder, and had a prolonged aPTT (46 sec), FVIII level of 14%, and VIII inhibitor titer 2∼5 BU/ml. Direct sequencing of FVIII was performed via amplification for all 26 exons, including the 5′-UTR and 3′-UTR region, using the 35 synthesized primers. Sequencing was conducted using BigDye Terminator cycle sequencing kit on an ABI 3730XL DNA analyzer (Applied Biosystems, Foster City, CA). Sequence variations were analyzed with CLC main workbench program (CLC, Aarhus. Denmark). Firstly, we analyzed translational region of FVIII gene. But we couldn't find any sequence variation. Then we analyzed the sequence of untranslationed region, 5′-UTR and 3′-UTR. As a result, we identified gene variation of substitution to c.8889G>A in the 3′-UTR. We speculate that this variation may have affected the RNA processing or mRNA stability. Thus we need to study about the relationship between this sequence variation and FVIII function. Also, we will investigate whether this gene variation is functional mutation. The cause of acquired hemophilia remains obscure. Variations in FVIII molecules including in untranslatable 5′- or 3′-region should be studied further to delineate the cause of antibodies in acquired HA. We expect that the accumulation of sequence variation can help to understand the cause of acquired hemophilia through this study.

Disclosures:

No relevant conflicts of interest to declare.
An in-Vivo Model of T Cell-Mediated Rejection of Human Hematopoietic CD34+ Stem Cells Using NOD/SCID γnull (NOG) Mice.
Authors: Nicolini Benedetta , Mahmud Dolores , Mahmud Nadim , Nucifora Giuseppina , Rondelli Damiano
Published: October 2019

Abstract 4474

We have previously demonstrated that human CD34+ cells include subsets of antigen presenting cells capable of stimulating anti-stem cell T cell alloreactivity in-vitro. In this study we transplanted human CD34+ cells and allogeneic T cells in a NOD/SCID γnull (NOG) mouse model and evaluated the occurrence of stem cell rejection as well as xenogeneic graft-versus-host disease (GVHD) following the infusion of different doses of T cells. After sublethal irradiation NOG mice were cotransplanted with 2×105 CD34+ cells and HLA mismatched CD4+CD25- T cells at 1:0 (control), 1:2 or 1:10 CD34+ cell: T cell ratio (n=5-10 mice per group). Hematopoietic stem cell and T cell engraftment was assessed in the bone marrow and in the spleen 6 weeks following transplantation or earlier in case the animals died. Control mice transplanted with CD34+ cells alone showed a high level of stem cell engraftment (huCD45+ cells: 60±10%) in the bone marrow, encompassing CD19+ B cells (64±4%), CD34+ cells (18±1%), CD33+ myeloid cells (7±1%), CD14+ monocytes (3±1%), and no T cells within huCD45+ cells. In contrast, mice that were transplanted with CD34+ cells and 4×105 (1:2 ratio) or 2×106 (1:10 ratio) T cells had only 9±2% and 3±1% huCD45+ cells, respectively, in the bone marrow (p=0.01). Moreover, marrow samples of mice cotransplanted with CD34+ cells and T cells at 1:2 or 1:10 ratio included >98% huCD3+ T cells and no CD34+ cells. Spleen engraftment of huCD45+ cells was lower (25±8%) in control mice (1:0 ratio) as compared to 66±10% and 36±11% in 1:2 and 1:10 groups, respectively (p=0.05). As observed in the marrow, also the spleen of animals receiving CD34+ and T cells included >98% CD3+ T cells. Among the T cells, both in the marrow and in the spleen of mice in the 1:2 and 1:10 ratio groups, 60-70% were CD4+CD8- cells, 22-25% CD8+CD4- cells, 1-3% CD56+ cells, and 2-5% CD4+CD25+ cells. In mice receiving 4 ×105 T cells (1:2 ratio), on average 12±6% of the T cells in the bone marrow and spleen were CD4+CD8+. Only mice receiving 2×106 T cells (1:10 ratio) showed GVHD. This was demonstrated by fur changes, reduced survival (p=0.02) and weight loss (p=0.0001) compared to control mice or mice receiving a lower dose of T cells (1:2 ratio). The marrow engraftment of CD3+ cells with disappearance of CD34+ cells in mice receiving low doses of allogeneic T cells, in the absence of evident xenogeneic GVHD, suggests that NOG mouse model represents a useful tool to study human stem cell rejection. This model will be also utilized to investigate new strategies of immunosuppressive cell therapy applied to stem cell transplantation in an HLA mismatched setting.

Disclosures:

No relevant conflicts of interest to declare.
Natural Killer (NK) Cell Recovery After Bone Marrow Transplantation in Mice: Early Emergence of a Novel Ly49+ Stage in Differentiation Independent of MHC Haplotype.
Authors: Murphy William , Redelman Doug , Barao Isabel
Published: October 2019

Abstract 4477

NK cells play critical roles in resistance to viral infections and in cancer. NK cells exist as subpopulations of cells that bear inhibitory and/or activating receptors to MHC. In mice, these are the Ly49+ subsets which have been shown to play a role in the rejection of bone marrow allografts as well as resistance to CMV. These Ly49 receptors also play a central role in the “education”, “arming” or “licensing” of NK cells. NK cell recovery after bone marrow transplantation is thought to proceed quickly but the acquisition of the Ly49 receptors has been incompletely characterized. NK cell differentiation has for the most part been characterized through in vitro models. We therefore examined the recovery of NK cells after syngeneic BMT in mice and assessed the effects of MHC on the recovery of the Ly49+ subsets using congenic recipients. NK cells were rapidly detected in mice as early as 14 days after BMT. Interestingly, the dominant population observed had a mature NK cell phenotype based on the expression of CD94, CD43, CD11b, etc. However, the majority of NK cells had a unique expression of Ly49G2 single positive NK cells with median fluorescence intensity (MFI) approximately twice as high as on NK cells from normal animals. This phenotype was not observed in untreated normal mice and occurred in B6 and B10 (H2b) as well as B10.D2 (H2d) strain mice showing independence from MHC. When these cells were sorted and assessed for cytotoxic activity, the cells had comparable killing efficiency as NK cells from untreated mice. Over time, NK cells with normal Ly49 subset distribution and phenotype were observed with the disappearance of this earlier subset. However, total splenic NK cell numbers remained significantly reduced in the BMT recipients as long as 120 days after BMT and despite normal recovery and numbers of T cells. These results demonstrate the existence of novel stage(s) in NK cell differentiation that occur independently of MHC and that can be characterized by sole expression of Ly49G2 at high levels. However, deficits in NK cell numbers persist in mice for extended periods of time. These findings suggest that NK cell recovery may occur in waves with some inhibitory receptors programmed to repopulate first and that surface expression intensity also needs to be assessed. Furthermore, the long-term deficits in total numbers suggest that overall activity may be compromised for extended periods clinically post-BMT.

Disclosures:

No relevant conflicts of interest to declare.
CFU-GEMM Infused Influences Immunologic Recovery in Children Older Than 7 years After Hematopoietic Stem Cell Transplantation.
Authors: Drabko Katarzyna , Choma Marta , Zaucha-Prazmo Agnieszka , Wojcik Beata , Winnicka Dorota , Kowalczyk Jerzy
Published: October 2019

Abstract 4483

Introduction

Reconstitution of immunity is considered as one of the most important factors predicting outcome after hematopoietic stem cell transplantation (HSCT). Age of the recipient as well as graft quality reflect on this process however this influence is not completely understood yet. In this study we aimed to evaluate the influence of graft quality on recovery of lymphocyte subpopulation.

Patients and Methods

The total number of 63 patients who underwent allogeneic transplantation in one center between May 2002 and November 2008, were included into the study. Median age of the patient was 8,6 (range 0.2-18) yrs. Patients were divided into 2 age groups: group 1 (n=26) children age 0,2-7 and group 2 (n=37) children >7 yrs. In all cases quality of graft were assessed by counting WBC, CD34 cells and CFU-GEMM. 45 patients (21 in group 1 and 24 in group 2) were available for evaluation of immune reconstitution: in those patients the absolute number of lymphocytes CD3/CD19 (B) cells, CD3/CD4 (T helper) cell, CD3/CD8 (T suppressor) cells and CD3/CD16+56 (NK) cells were measured 3 and 6 months after transplantation.

Results

Younger children (group 1) received higher median number of transplanted nucleated cells (4.9×108 vs 2.5×108, p=0.008), CD34 cells (5.6×106 vs 2.1×106, p=0.02) and CFU-GEMM (2.25×104 vs 1.17×104, p=0.01) than older ones (group 2). No differences were found in absolute values of B, T-helper, T-suppressor and NK cells at 3 and 6 months after transplantation (Table 1). In older children (group 2), but not in younger ones, the number of GFU-GEMM transplanted negatively correlated with number of T-suppressor cells 3 months post HSCT (p<0,05; r=-0,7) and positively with number of T-helper cells 6 moths after HSCT (p<0,05; r=0,73).

Conclusions

Number of CFU-GEMM infused influences immunologic recovery in children older than 7 years after HSCT. Graft quality correlates with number of T-suppressor cells and T-helper cells during first 6 months after HSCT and these changes may contribute to post transplant complications.

Supported by grant MNiSW of Poland N407 117 35

Disclosures:

No relevant conflicts of interest to declare.
Idiopathic Pneumonia Syndrome in Mice After Allogeneic Bone Marrow Transplantation: Association Between Idiopathic Pneumonia Syndrome and Acute Graft-Versus-Host Disease.
Authors: Liu Qifa , Ning Juan , Zhang Yu , Luo Xiaodan , Fan Zhiping , Wu Xiuli
Published: October 2019

Abstract 4502

Objective

To explore the association between idiopathic pneumonia syndrome (IPS) and acute graft-versus-host disease (aGVHD) in allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Methods

An aGVHD model was established using a mouse transplant (C57BL/6□BALB/c). Chest computed tomography (CT) scans were dynamically performed and histopathology and cytokine levels in lung tissues were kinetically detected using the Linchip system in three experimental groups: mice receiving simple irradiation, syngeneic transplants and allogeneic transplants.

Results

The incidence of aGVHD was 100% in allogeneic transplant mice. CT revealed bilateral diffuse infiltrates in the lungs of most mice with aGVHD vs normal lung tissue in syngeneic transplant mice. Histopathology confirmed mice with aGVHD had acute pneumonitis. Immunohistochemistry showed that during aGVHD onset the infiltrates were mainly CD4+ T cells whereas the domination of CD4+ T-cell was replaced by CD8+ T-cell during aGVHD progression. TNF-α and IFN-γ levels within lung tissues of the three groups were higher than in normal controls on day +3 and +7 post-transplant. On day +7, TNF-α levels were higher in allogeneic than in syngeneic transplant mice, but there was no statistical difference in IFN-γ levels. On day +12 and +16, TNF-α levels were significantly higher in allogeneic than in syngeneic transplant mice, but IFN-γ levels were lower in allogeneic than in syngeneic transplant mice.

Conclusions

The aGVHD is the underlying cause of IPS. T cells and TNF-α may play a role in the pathogenesis of aGVHD-induced IPS. IPS progression may be associated with decreasing levels of IFN-γ within the lung tissues.

Disclosures:

No relevant conflicts of interest to declare.
Defining Outcomes in Hispanic Aggressive Non-Hodgkin Lymphoma Patients.
Authors: Paraskos Lara M , Blum Mariela A. , Escalon Maricer , Ferrell Annapoorna , Kobetz Erin , Rosenblatt Joseph
Published: October 2019

Abstract 4542

Background

Multiple studies evaluating outcomes for oncology patients have demonstrated inferior overall survival rates among African-Americans. Hispanics comprise the largest ethnic minority in the United States. Surprisingly outcomes for Hispanic aggressive non-Hodgkin lymphoma (NHL) patients have not been evaluated and are therefore largely unknown. We aim to identify differences in epidemiology, treatment modalities and outcomes of Hispanic patients treated for aggressive NHL at our institution between the years 2000-2004.

Methods

We reviewed the medical records of 82 patients with aggressive type NHL who were identified using the tumor registry. Exclusion criteria include indolent and highly aggressive lymphomas per WHO classification as well as lymphomas related to AIDS or organ transplantation. Standard statistical analyses, including Kaplan-Meier survival estimates and Chi-squared analysis for group comparisons were used. P value of <0.05 was considered statistically significant.

Results

Of the 82 patients, 46 were self-reported Hispanic in origin; 36 were non-Hispanic. There were no significant differences with respect to age at diagnosis, LDH level, stage, or complete remission rate. Kaplan-Meier estimate of median overall survival (OS) of the cohort was 3.8 years with no statistically significant differences observed between the Hispanic and non-Hispanic ethnic groups. (P = 0.816).

Conclusion

Ethnic patterns of disease occurrences have been reported, but responses to treatment and outcome for Hispanic patients have not been established. Interestingly from our preliminary analysis, there appears to be no statistically significant difference in overall survival between Hispanic and non-Hispanic patients. Further evaluation is warranted.

Disclosures:

No relevant conflicts of interest to declare.