bluuebunny/crossref_metadata_2025 huggingface dataset:
Cost Comparison of Hematopoietic Stem Cell Transplantation and Conventional Therapy for Patients with Thalassemia Major in China
Authors: Tan Wanxia , Li Chunfu , Wu Xuedong , He Yuelin , Feng Xiaoqin , Liao Jianyun , Liu Huaying , Xu Wenfeng , Ren Yuqiong
Published: October 2019

Background: The conventional treatment (CT) for beta- thalassemia major (TM) includes regular transfusion accompanied by iron-chelating therapy. However, this laborious treatment by given desferrioxamine (DFO) subcutaneously for 8 to12 hours per days, at least 5 days per week with/without deferiprone (DFP) has led to poor compliance, even though, the new medicine named deferasirox (DFX) has been introduced in China recent years. Nevertheless, the high cost makes it difficult to use widely for many families. Hematopoietic stem cell transplantation (HSCT) provides an alternative curative option for TM patients. To our knowledge, data from China has not been available in the literature on cost comparison between HSCT and CT.

Aims: The principal aim of our study is to compare the lifetime undiscounted mean cost (UMC) of hematopoietic stem cell transplantation (HSCT) with UMC of conventional therapy (CT) in beta-thalassemia major (TM) patients and to investigate the relationship of the clinical features to cost outcomes of HSCT.

Methods: We estimated UMC of 93 TM-HSCTs between 2011 and 2012 with a median age of 6 years (range, 3-16) and a median follow-up time of 3 years (range, 2.4 -3.8). The relationship between the UMC of HSCT and patient characteristics were analyzed. The UMC of 93 TM-HSCTs was compared with UMC of CT based on total 1526 TM patients. Age was used as matching variant, and the mean cost of each age was calculated, then cumulative cost was further adjusted for age in patients.

Results: UMC of TM-HSCT was CNY (Chinese Yuan) 235,254/USD 37,664 (95% confidence interval (CI) CNY208, 081-262,719/USD 33,293-42,035) with mean hospital stay of 60.5 days (95% CI 49-71). UMC of 20 years of follow-up and total undiscounted lifetime (55 years) for patients underwent HSCT were CNY 345,317/USD55, 251 and CNY 465,975/USD 74,602 respectively. However, the corresponding costs of patients undergoing CT were CNY 2,101,488/ USD336, 238 and CNY 7,489,519/ USD1, 198,323 respectively. Patient characteristics were helpless to predict the costs. HLA-mismatched transplants increased significantly UMC of HSCT than matched transplants (USD 35,818 vs. USD 52,771; p<0.001). The development of GVHD were associated with higher costs (USD 63,933 vs. USD 44,547; p = 0.001).

Conclusions: Cost comparison of HSCT and CT suggests that HSCT is an efficient and high cost-effective treatment for TM patients. Mismatched donor transplant increases the cost of HSCT.

Keywords: hematopoietic stem cell transplantation, iron overload, cost analysis

Figure 1. Cumulative lifetime treatment cost of CT and HSCT (USD) Figure 1. Cumulative lifetime treatment cost of CT and HSCT (USD)

Disclosures

No relevant conflicts of interest to declare.
Hodgkin Lymphoma Variant of Richter Transformation: Morphology, EBV Status, Clonality and Survival Analysis a Retrospective Study of 77 Patients
Authors: Xao Wenbin , Chen Wayne , Sorbara Lynn , Davies-Hill Theresa , Pittaluga Stefania , Raffeld Mark , Jaffe Elaine S
Published: October 2019

The classical Hodgkin lymphoma variant of Richter transformation (CHL-RT) occurs rarely in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). Two morphological patterns have been described: type I with Hodgkin/Reed-Sternberg (HRS) cells scattered in a CLL background, and type II with typical CHL morphology. HRS cells are frequently positive for EBV and can be clonally related or unrelated to CLL. The clinical significance of the different morphological patterns is unclear. What factors dictate the cellular derivation of the HRS cells remains elusive.

We retrospectively reviewed 77 cases of CHL-RT submitted to our consultation service. Clinicopathological characteristics were summarized, EBV status was examined, and clonality was analyzed after microdissection of HRS-cells and CLL cells.

Patients with the type I pattern (N=26) had a significantly shorter time to progression from CLL to CHL-RT than those with type II pattern (N=51, 15 vs. 49 months, p<0.0001, see Figure 1A). Consistent with these data, 27% of patients with the type I pattern had a prior CLL history as compared to 73% with the type II pattern. 12% (6/51) of type II cases had extranodal involvement (sites other than bone marrow) while none of type I cases did. Three patients with sequential biopsies progressed from type I to II and 2 had an aggressive clinical course. HRS cells were positive for EBV in 71% (55/77) of patients. Clonality analysis was performed in 33 cases: HRS cells were clonally related to the underlying CLL in 14 cases and unrelated in 19 cases. Among all the features examined, ZAP-70 expression of the CLL cells, but not EBV status or morphological pattern, was strongly correlated with clonal relationship: all 14 clonally related cases were negative for ZAP-70 while 74% (14/19) of the clonally unrelated cases were positive for ZAP-70. Overall median survival after the diagnosis of CHL-RT was 44 months. Advanced age was an adverse risk factor for survival (p<0.05, see Figure 1B).

In conclusion, we provide evidence that type I morphology is more likely an early stage of CHL-RT and can progress to type II. The majority of CHL-RT cases are EBV positive. Clonal relationship in RT is determined by ZAP-70 and thus likely IGHV mutational status. Advanced age is associated with inferior survival.

Figure 1. A, Time to progress from CLL to CHL-RT. B, Kaplan-Meier analysis of overall survival. Figure 1. A, Time to progress from CLL to CHL-RT. B, Kaplan-Meier analysis of overall survival.

Disclosures

No relevant conflicts of interest to declare.
LRPAP1 Is a Frequent B-Cell Receptor Antigen in Mantle Cell Lymphoma (MCL)
Authors: Thurner Lorenz , Hartmann Sylvia , Preuss Klaus-Dieter , Fadle Natalie , Kemele Maria , Regitz Evi , Pott Christiane , Bohle Rainer-Maria , Hansmann Martin-Leo , Pfreundschuh Michael
Published: October 2019

Introduction: Chronic antigenic stimulation may play an important role in the pathogenesis of malignant lymphomas. Although most MCL cases are believed to have an antigen-naive B cell as cell of origin, overrepresentation of certain VH genes has been reported. Therefore we screened BCRs from MCLs for possible antigens.

Methods: BCRs were expressed as recombinant Fabs based on corresponding pairs of functional variable region heavy and light chain genes, which had been amplified from isolated genomic DNA of snap-frozen MCL specimens and established MCL cell lines. The purified BCR-Fabs were checked for binding to proteins expressed on macroarrays of human cDNA expression libraries and on bacterial lysates. In addition, sera from patients with MCL were screened for antibodies against respective BCR antigens.

Results: The recombinant MCL-BCR derived Fabs from 9 patients and of four established MCL cell lines were tested on protein arrays. Recombinant lymphoma-BCR-derived Fabs from 4/9 patients and from 1/4 MCL cell lines reacted with human low density lipoprotein receptor-related protein associated protein 1 (LRPAP1). Specific secondary modifications of LRPAP1 explaining its autoimmunogenicity were not found. 8/30 patients with MCL had anti-LRPAP1-antibodies in their serum, which was the case in only 1/200 healthy controls. Finally, LRPAP1 specifically induced proliferation of Maver1 cells that express a BCR with specificity for LRPAP1.

Conclusions: LRPAP1 is the first molecularly defined antigenic target of MCL-BCRs. The high frequency of LRPAP1-reactive BCRs in MCL suggests a role of LRPAP1 in the pathogenesis of MCL, even in cases with unmutated VH genes. The prevalence of LRPAP1-antibodies in MCL patients and healthy controls identifies LRPAP1-antibody as the first serologic risk factor for MCL (odds ratio: 72.36)

Supported by Wilhelm-Sander-Stiftung

Disclosures

No relevant conflicts of interest to declare.
Central Nervous System Involvement By Chronic Lymphocytic Leukemia
Authors: Strati Paolo , Uhm Joon , Kaufmann Timothy , Parikh Sameer A. , Hanson Curtis A. , Chaffee Kari , Achenbach Sara , Call Timothy G. , Shanafelt Tait D.
Published: October 2019

INTRODUCTION. Although uncommon, involvement of the central nervous system (CNS) is the most common extramedullary manifestation of Chronic Lymphocytic Leukemia (CLL). Nonetheless, a broad array of conditions can lead to neurologic symptoms in CLL patients and distinguishing between clinically significant CLL involvement of the CNS and other etiologies can be challenging. The actual prevalence of CNS involvement by CLL is unknown, the only available data being case reports and small case series.

METHODS. Between 01/1995 and 11/2014, 186 of the 4317 (4%) patients with CLL followed at our center underwent an MRI of the CNS (e.g. brain, spine) and/or a lumbar puncture (LP) with cerebral spinal fluid (CSF) analysis to evaluate neurologic symptoms. As the mere presence of CLL cells in the CSF is not diagnostic of clinically significant CNS disease, a final diagnosis of clinically significant CNS involvement by CLL was established by the collaborative review of the pathologist, neurologist and treating hematologist based on comprehensive work-up and multi-disciplinary evaluation.

RESULTS. After evaluation, the etiology of neurologic symptoms was clinically significant involvement of the CNS by CLL in 19 (10%) patients, CNS Richter Syndrome (RS) in 15 (8%), infection in 42 (23%), autoimmune conditions in 31 (17%), other cancer in 9 (5%), and another etiology in 70 (37%). The sensitivity of LP to detect clinically significant CNS involvement by CLL was 89%, however its specificity was only 42% where CLL cells were also frequently observed in the CSF in concomitance with inflammatory processes, such as infections and autoimmune disease. Factors associated with clinically significant CNS involvement by CLL/RS were mutated IGHV (p=0.04), low CSF glucose (p=0.02), elevated CSF total nucleated cells (TNC)(p=0.004), lymphocytes (p=0.02) and CLL cells, both as absolute count (p=0.05) and percentage of TNC (p=0.02). Median OS among patients with clinically significant CNS involvement by CLL or RS were 21 and 11 months, respectively. Median OS for patients with neurological symptoms secondary to infection was 6 months, to autoimmune process was 63 months, to other cancers was 19 months, and to other non-CLL related etiologies was 37 months.

CONCLUSIONS. Clinically significant CNS involvement by CLL and RS are rare conditions. Neurologic symptoms in patients with CLL are attributable to non-CLL-related etiologies in the majority of cases, even when CLL B-cells are present in the CSF. Analysis of the CSF has high sensitivity but limited specificity to distinguish clinically significant CNS involvement by CLL from other etiologies. Comprehensive evaluation is required before attributing neurologic symptoms to CLL.

Disclosures

No relevant conflicts of interest to declare.
Management of T-Cell Large Granular Lymphocyte Leukemia with Methotrexate or Cyclophosphamide
Authors: Kovacs Matthew R. , Hsia Cyrus C. , Lazo-Langner Alejandro , Kovacs Michael J.
Published: October 2019

Background. T-Cell Large Granular Lymphocyte Leukemia (T-LGL Leukemia) is an extremely rare lymphoproliferative disorder which can originate from either mature T cells (CD3+) or natural killer cells (CD3-). T-LGL leukemia is a slowly progressing disease, rarely presenting with an aggressive course and in general patients have prolonged survival. Treatment is commonly monotherapy with methotrexate (with or without prednisone), cyclosporine, or cyclophosphamide. Herein we review our experience with the management of T-LGL in the last 15 years.

Patients and Methods. We conducted a retrospective cohort study of all patients diagnosed with T-LGL at our center between 2000 and 2015. Patients were included if they had a positive study for T-Cell Receptor gene rearrangement. Response was evaluated using the criteria of Loughran et al (Leukemia 2015). Data was analyzed using descriptive statistics.

Results. We included 23 patients, (16 male). All of the patients were caucasian with the exception of two. The average age at diagnosis is 65.1 years. Patients were treated for symptomatic cytopenias or splenomegaly with transfusions and/or chemotherapy. Six patients did not need any treatment. Fourteen of the 23 patients were treated with oral methotrexate monotherapy. The methotrexate dose ranged from 5mg/week to 15mg/week orally. Seven patients had a complete response, 2 had a partial response, 3 patients failed treatment, 1 patient was not evaluable, and 1 was stable. Four patients were treated with methotrexate and prednisone. Two patients obtained a complete response, with 1 partial response, and 1 patient was not evaluable due to the short duration of the prescription. Nine patients were treated with oral cyclophosphamide at doses of 50mg or 100mg po daily. Four patients achieved a complete response, 2 patients achieved a partial response, while the other 3 patients did not respond. Only 2 patients were treated with oral cyclosporine, at 400mg/day and at 500mg/day. One patient failed treatment while the other is still on therapy. Two patients died while on the study at 22 and 42 months, both deaths were due to other illnesses not associated with T-LGL Leukemia. The median time since diagnosis for the remaining patients is 41 months.

Conclusion. T-LGL is a rare lymphoproliferative disorder. Most patients responded to simple oral therapy with methotrexate or cyclophosphamide and patients generally have prolonged survivals.

Disclosures

Lazo-Langner: Bayer: Honoraria; Pfizer: Honoraria. Kovacs:Daiichi Sankyo Pharma: Research Funding; LEO Pharma: Honoraria; Bayer: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding.
Clinicopathological Analysis of CNS Involvement in Multiple Myeloma
Authors: Togano Tomiteru , MINE Sohtaro , Miwa Akiyoshi , Hagiwara Shotaro
Published: October 2019

Background

Extramedullary disease (EMD) is often observed in end stage of multiple myeloma (MM).However, central nervous system (CNS) involvement is very rare. Thus, little is known about CNS involvement of MM. We conducted clinicopathological analysis.

Methods

We reviewed medical records and pathological specimens of multiple myeloma cases between 1979 and 2015 at the National Center for Global Health and Medicine in Tokyo, Japan. Patient information and duration of illness, clinical finding including type of monoclonal protein, Durie & Salmon's (DS) staging, treatment and pathological findings were collected. CNS involvement was diagnosed pathologically.

Results

We found 15 cases of CNS involvement multiple myeloma. In 15 cases, 66.6 % was male. Mean age and the duration of illness were 56 years old and 35.7 months, respectively. DS stage was 3A (46 %), 2A (20 %), 2A (20 %), 1A (13 %). Monoclonal protein was IgG (46 %), IgA (33 %), BJP (0.6 %) and non-secretary (13 %). Lambda chain was 62 %. Manifestation at diagnosis CNS involvement was disturbance of consciousness (40 %), visual disturbance (20 %), dysphagia (13%), paresthesia of extremities (20 %), vomiting or nausea (13 %). Other organ involvement was spleen (60 %), pancreas (53 %), liver (53 %), adrenal gland (46 %), testis (31 %) and plasma cell leukemia (40 %). In two cases, peripheral nerve involvement was found. Seven of 15 patients were previously treated with novel agents such as bortezomib, thalidomide, and lenalidomide. Recent 5 years, the frequency of CNS involvement increased more than threefold (1.0 case/year), compared to 1979-2010 (0.3 case/year). In all cases, myeloma cells infiltrated dura mater or subarachnoid cavity. Infiltration in parenchyma of brain was seen in only 2cases. Myeloma cells were seen at loose section of connective tissue around vascular in most cases. Interestingly, myeloma cells were often infiltrated at peripheral nerve, spinal cord cavity and central canal without spinal cord.

Conclusions

In the era of novel agents, the incidence of CNS involvement in patients with multiple myeloma has increased. We found myeloma cells were often infiltrated at peripheral nerve, spinal cord cavity and central canal without spinal cord. Our study revealed that exposure to novel agents, lambda type MM, multi-organ involvement and plasma cell leukemia were associated with CNS involvement.

Disclosures

Hagiwara: Celgene Corporation: Membership on an entity's Board of Directors or advisory committees.
IgM Multiple Myeloma Presenting As Hyperviscosity Syndrome with Isolated Skin Manifestation
Authors: Ghelani Ghanshyam , Thomas Lisa , Shi Qi , Jecmenica Midaen
Published: October 2019

Background:

Immunoglobulin M-producing multiple myeloma (IgM MM) accounts for less than 1% of all myeloma cases. Because the disorder is rare,its clinical characteristics and long-term prognosis remain unknown. Hyperviscosity occurs from pathologic changes of either cellular or protein fractions of the blood such as are found in MM (particularly IgA and IgG3) and other diseases.

Case Presentation

A 65-year-old male smoker presented to emergency room (ER) with headache, dizziness, shortness of breath, symmetrical finger pain, nose bleeds, and blood in stool. On lab work hemoglobin was 7.9 gm/dl. Review of the peripheral blood smear showed atypical lymphocytes. CT chest showed left axillary and supraclavicular lymphdenopathy. Serum protein was 13 gm/dl, Serum protein electrophoresis showed a monoclonal IgM kappa gammopathy with UIEP confirming the bence jones proteinuria. A bone marrow biopsy showed about 80% cellularity with diffuse and solid neoplastic plasma cell infiltrates that were CD138+, CD20- and CD3-. Flow cytometric analysis of the bone marrow aspirate demonstrated a small fraction of clonal plasma cell population that were CD38+, CD138+, CD45-, and CD56-, Fluorescent in Situ Hybridization confirmed neoplastic plasma cells with kappa light chain restriction, and cyclinD1-. On examination, the patient had a erythematous skin changes and edematous bilateral symmetrical finger findings.

Discussion:

MM with IgM gammaglobulin is a rather distinct subtype of MM displaying clinical and pathologic features of both MM and WM. The clinical presentation of WM is similar to that of MM except that organomegaly is common in WM but is uncommon in MM and lytic bone disease and renal disease are uncommon in WM but are common in MM.

The criteria for diagnosis of IgM myeloma (and its differentiation from WM) requires the presence of either lytic bone lesions and/or evidence of the t(11;14) translocation. It is also characterized by negative CD20, D56 and CD117 phenotype. All the reported cases of IgM myeloma had been treated with melphalan and prednisolone with suboptimal results. Some patients were treated with VAD (vincristine, adriamycin and dexamethasone) regimen, others with CTD protocol. The results were similar to the MP regimen. Radiotherapy was mainly used as palliative measure.

Conclusion:

Our case suggests that IgM multiple myeloma can presents as hyperviscosity syndrome with isolated skin manifestation and may have unique clinical characteristics.

Disclosures

No relevant conflicts of interest to declare.
Homozygous Mutation of the ETS DNA-Binding Domain of FLI1 Causes a Bleeding Disorder with Giant Alpha Granules Similar to Paris-Trousseau Thrombocytopenia
Authors: Stevenson William S , Rabbolini David John , Brighton Timothy , Mackay Joel , Ward Christopher M , Morel-Kopp Marie-Christine
Published: October 2019

Deletion of a variable region on chromosome 11q containing FLI1 causes a platelet-related bleeding disorder in Paris-Trousseau thrombocytopenia and Jacobsen syndrome. We report a kindred with the autosomal recessive inheritance of an ETS domain mutation of FLI1, c.970C>T, that causes macrothrombocytopenia with large alpha granule fusion similar to that observed in Paris-Trousseau thrombocytopenia but with no other syndromal features of Paris-Trousseau or Jacobsen syndromes. Affected individuals are moderately thrombocytopenic (mean = 71 x109/L), have absent collagen-induced platelet aggregation and a lifelong mucosal bleeding history. Platelet MYH10 levels were increased in affected members of the kindred consistent with previous reports of elevated MYH10 in Paris-Trousseau thrombocytopenia. Luciferase reporter assays in HEK293 cells demonstrate that the mutant FLI1 transcript is associated with decreased transcription at the FLI target genes GP6, GP9 and ITGA2B compared to the wild-type transcript (23 vs 31, n=9, P<0.01; 3.8 vs 6.5, P<0.01, n=12; 11 vs 14, n=9, P=0.01, respectively). This transcriptional change was consistent with reduced expression of GPVI (P<0.01), GPIbIX (P<0.01) and GPIIbIIIa (P=0.04) observed on western blotting of platelet lysates from affected family members. This mutation replaces the conserved Arg324 with a tryptophan in the DNA-binding loop between the alpha-2 and alpha-3 helices of the FLI1 ETS domain. Protein modelling suggests that Arg324 does not directly bind DNA but may instead make direct contact with an N-terminal autoinhibitory domain of FLI1 that is considered to regulate DNA-binding affinity through a transition between a folded and unfolded state. This mutation may disrupt this important conformational change. These data suggest abnormalities of FLI1 function may be responsible for the complex platelet defect observed in Paris-Trousseau thrombocytopenia and Jacobsen Syndrome and confirm the role of FLI1 as an important transcriptional regulator of normal platelet development.

Disclosures

No relevant conflicts of interest to declare.
In vivo Stem Cell Clonal Dynamics
Authors: Camargo Fernando D.
Published: October 2019

Tremendous progress has been achieved in the characterization of the hematopoietic system over the past two decades. Historically, the main experimental approach used to elucidate and define these cellular relationships in the bone marrow (BM) has been the transplantation assay. For this reason, most of our knowledge about the in vivo properties of hematopoietic stem cells (HSCs) and progenitor cells has been derived from studies in the transplant context. Because of the lack of tractable systems, the mechanistic nature of non-transplant hematopoiesis has remained largely unexplored. Over the past several years, my laboratory has developed novel genetic tools for the clonal tracing and imaging of hematopoietic populations in the unperturbed niche that aim to bring insight into the biology of stem and progenitor cells in situ. Our work using a transposon-mediated cellular tagging approach indicated that progenitors, and not the classical long-term HSCs, are the cells mainly responsible for the day-to-day production of blood cells in the adult. Our data also suggested that lineage restricted progenitors are the main contributors to hematopoiesis at steady state. These data represent the first systematic analysis of clonal fate in an unperturbed hematopoietic niche and revealed a novel cellular mechanism for homeostatic blood regeneration. We have now utilized this clonal tracing model to bring insight into the dynamics of stem and progenitor biology during embryonic hematopoiesis and in the severely aged hematopoietic system. These data will be discussed at the meeting.

Disclosures

Camargo: Cell Signaling Technologies: Consultancy; Vital Therapies: Consultancy.
Hypoxia Drives AML Proliferation in the Bone Marrow Microenvironment Via Macrophage Inhibitory Factor
Authors: Abdul-Aziz Amina M , Shafat Manar S , Zaitseva Lyubov , Lawes Matthew J , Rushworth Stuart A , Bowles Kristian M
Published: October 2019

Introduction

Hypoxia is an important component of the bone marrow microenvironment and the hematopoietic stem cell niche. Studies have shown that hypoxia contributes to the development and maintenance of acute myeloid leukemia (AML) cells within the bone marrow microenvironment. Hypoxia is principally maintained by members of the hypoxia-inducible factor (HIF), in particular HIF1a and its target genes, including MIF. We have previously shown that AML cells express constitutively high macrophage migration inhibitory factor (MIF) which drives IL-8 expression by the BM-MSC which in turn supports AML cell survival and proliferation. The aim of the present study is to determine if there is a connection between the role of hypoxia in regulating AML survival and MIF survival signals. Furthermore we investigate the role BM-MSC in regulating the hypoxic response.

Methods

Primary AML and BM-MSC were isolated from AML patients following informed consent and under approval from the UK National Research Ethics Service (LRCEref07/H0310/146). AML cell lines and primary AML blasts were cultured under normoxic (20% oxygen) or hypoxic conditions (1% oxygen) for 4 - 24 hours, mRNA expression of MIF, HIF1a, VEGF and IL-8 were determined by RT-PCR. MIF and IL-8 protein was determined using target specific ELISA. HIF1a protein expression was determined by western blotting. Hypoxia-mimetic agents, cobalt chloride (CoCl2) and desferrioxamine (DFO) were used. Cell proliferation was determines using CellTiter Glo and trypan blue exclusion. CFU-assays were performed using complete methylcellulose media.

Results

To determine If MIF is regulated by HIF1a in AML cells, we mimicked hypoxic conditions using CoCl2 and DFO in AML cells. Both CoCl2 and DFO upregulate MIF transcription and protein expression in OCI-AML3 cell lines and in primary AML blasts. Moreover, hypoxia increases both MIF mRNA expression and MIF chemokine expression compared to normoxic conditions. Lentiviral mediated knockdown of MIF in AML cells show significantly reduced cell proliferation and colony formation in methylcellulose media. Recombinant MIF induced interleukin-8 in AML blasts and the MIF inhibitor blocked MIF induced IL-8 release. Lentiviral mediated KD of HIF1a decreased MIF expression in human AML cells and a significant reduced their proliferative capacity. Finally we found that hypoxia increased MIF in AML blasts which was further increased when in co-culture with BM-MSC.

Conclusions

The results reported here suggest that hypoxia significantly affects the expression of the survival cytokine MIF in AML blasts. Furthermore, we show that BM-MSC regulate HIF1a induced MIF expression in AML under hypoxic conditions. We propose this hypoxia regulated HIF1a/MIF axis is essential to blast survival in the bone marrow niche.

Disclosures

Rushworth: Infinity Pharmaceuticals: Research Funding.
TP53 Immunostaining in Double-Hit and Double-Expressing High-Grade B-Cell Lymphoma
Authors: Oduro Kwadwo Asare , Kovach Alexandra E. , Abramson Jeremy S. , Hasserjian Robert P. , Sohani Aliyah R
Published: October 2019

Background: Diffuse large B cell lymphoma (DLBCL) is the most common lymphoma, but comprises a heterogenous group. Recent studies have identified aggressive subsets of DLBCL including double-hit lymphomas (DHL, with rearrangements of both MYC and BCL2 oncogenes and often classified in a separate DLBCL/Burkitt overlap category) and double-expressing lymphomas (DEL, which overexpress both MYC and BCL2). These subsets respond poorly to standard R-CHOP chemotherapy and account for most of the mortality associated with DLBCL. While recent studies have associated TP53 protein overexpression with worse prognosis in DLBCL, the effect of TP53 aberrations on these more aggressive DLBCL subsets is still uncertain.

Design: We performed a retrospective single institution analysis of a cohort of 26 DHL and a cohort of 65 R-CHOP-treated DLBCL, including 10 DEL. We recorded clinical information, treatment, and patient outcome. The DHL cases were treated with either R-CHOP or a more intensive regimen. A tissue microarray or recuts from original blocks were used for immunostains for TP53, BCL2, MYC, and cell-of-origin determination by Hans algorithm, which were scored blindly.

Results: TP53 expression (>10% of tumor cells) was significantly associated with higher expression of BCL2 (p=0.02), MYC (p=0.0009), and DEL status (p=0.005) in the DLBCL group. With respect to the association of DEL with TP53 expression, 7/10 (70%) cases of DEL were TP53+ compared to 10/55 (18%) of non-DEL DLBCL. There was no association with TP53 expression and cell-of-origin. No statistically significant difference in overall or relapse free survival between TP53+ and TP53- cases was identified in either cohort.

Conclusion: The findings in this small sample suggest that the relationship between TP53 staining and DLBCL outcome is more complex than previously reported, and may reflect an association of TP53 expression with DEL. The use of intensified treatment regimens (such as R-EPOCH) in the DHL cohort may abrogate any negative effects of TP53 overexpression in the TP53+ subset.

Disclosures

Abramson: Seattle Genetics: Consultancy; Gilead: Consultancy; Abbvie: Consultancy; Kite Pharma: Consultancy.
Uncovering Clonal and Subclonal Druggable Targets in Multiple Myeloma Using Omic Data
Authors: Scott Adam David , Yellapantula Venkata D , Yoon Christopher J , Wendl Michael , Tomasson Michael H. , Fiala Mark A , DiPersio John F. , Vij Ravi , Ding Li
Published: October 2019

The Multiple Myeloma Research Foundation (MMRF) CoMMpass trial is the keystone program working towards personalized medicine in multiple myeloma (MM). CoMMpass has characterized over 730 samples from 669 patients, a subset having time-course data, using multiple platforms and has made these data publicly available. Screening for druggable somatic mutations and gene expression outliers revealed great potential for repurposing existing pharmacotherapies.

We have developed and curated a Database of Evidence for Precision Oncology (DEPO) that includes 442 mutations and 49 genes with expression changes implicated as drug targets from 34 cancer types. We found 43.6% of CoMMpass samples have one of 26 somatic mutations that could be targeted by 9 different drugs, suggesting many drugs may be repurposed for use in MM. HotSpot3D, a protein-structure-guided analysis tool, showed 3.3% (24/730) of samples have mutations involving BRAF and KRAS, clustering with known drug targets, and another 2.1%(15/730) have mutations in clusters formed from a prior TCGA pan-cancer analysis involving 22 cancer types. This indicates additional potential drug targets and functional mutations in MM.

Interestingly, 11 samples (including relapse), have subclonal mutations in both KRAS and BRAF with variable allelic fractions, implicating different treatment requirements for tumor subpopulations and disease stages. Additionally, druggable gene expression outlier analysis of 591 samples reveals an average of nearly 5 outlier genes per sample from among 49 known target genes, with 18.1% (107/591) of samples with MYCN gene outliers as compared to MYC 1.4% (8/591), despite MYC being a known driver of MM. Other top outliers are DLL3 10.2%, EGFR 10.5%, FGFR1 10.2%, and FGFR2 12.5%. Our study highlights candidate drug targets previously omitted in MM. Taken together, it suggests that heterogeneity analysis and pharmaceutical repurposing could lead to substantially improved outcomes.

Disclosures

No relevant conflicts of interest to declare.
Development of a New BCMAxCD3 Duobody® Antibody for Multiple Myeloma
Authors: Pillarisetti Kodandaram , Baldwin Eric , Babich Alexander , Majewski Nate , Barone Linda , Li Yingzhe , Zhang Xiaochun , Chin Diana , Luistro Leopoldo , Mendonça Mark , Nanjunda Rupesh , Rudnick Stephen , Bellew Kevin , Elsayed Yusri , Attar Ricardo M. , Gaudet François
Published: October 2019

B-cell maturation antigen (BCMA) is a tumor necrosis factor (TNF) family surface protein predominantly expressed on terminally differentiated B-cells. BCMA signals through P38/NF-κB pathway upon binding to its ligands; a proliferation inducing ligand (APRIL) and B-cell activator of the TNF family (BAFF) and promote anti-apoptotic gene expression. BCMA expression is elevated in plasma blasts, plasma cells from spleen and bone marrow and correlates with disease progression in multiple myeloma (MM). BCMA expression in premalignant MM settings such as monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) also gives an opportunity for early cancer interception. To target cancer cells expressing BCMA, we developed a BCMAxCD3 bispecific antibody using the Genmab DuoBody® technology (Ab-957) to recruit T cells to BCMA-expressing MM cells so that T cells could be activated and induced to kill BCMA+ cancer cells. This antibody can induce cytotoxicity of BCMA+ MM cell lines in vitro (H929 cells: EC50=0.15nM, MM1.R cells: EC50=0.06nM, RPMI8226 cells: EC50=0.45nM) with a concomitant T cell activation (H929 cells: EC50=0.21nM, MM1.R cells: EC50=0.1nM, RPMI8226 cells: EC50=0.28nM). In contrast, this antibody was unable to kill BCMA- cancer cell line (MV4-11), demonstrating the specificity of the cytotoxicity. Ab-957 also inhibited tumor development or growth in two BCMA+ MM murine xenograft models inoculated with human T cells. Furthermore, this antibody could deplete BCMA+ cells in bone marrow samples from MM patient's in an ex-vivo assay with an average EC50 value of 2.5 nM. Lastly, Ab-957 is well-tolerated in cynomolgus monkey and is being developed for Phase I clinical trial in patients with multiple myeloma.

Disclosures

Pillarisetti: Janssen: Employment. Baldwin:Janssen: Employment. Babich:Janssen: Employment. Majewski:Janssen: Employment. Barone:Janssen: Employment. Li:Janssen: Employment. Zhang:Janssen: Employment. Chin:Janssen: Employment. Luistro:Janssen: Employment. Mendonça:Janssen: Employment. Nanjunda:Janssen: Employment. Rudnick:Janssen Pharmaceuticals R&D: Employment. Bellew:Janssen: Employment. Elsayed:Janssen: Employment, Other: stock options. Attar:Janssen: Employment. Gaudet:Janssen Pharmaceuticals R&D: Employment, Other: Stock options, Patents & Royalties: pending, not yet issued.
Transplant Associated Thrombotic Microangiopathy in Individuals with Fanconi Anemia
Authors: Myers Kasiani C. , Jodele Sonata , Nelson Adam S. , Goodridge Erica , Mehta Parinda A , Mueller Robin , Dandoy Christopher E. , Lane Adam , El-Bietar Javier A. , Davies Stella M
Published: October 2019

Objective: Transplant-associated thrombotic microangiopathy (TA-TMA) is an increasingly recognized complication of hematopoietic stem cell transplantation (HSCT) due to vascular endothelial injury. TA-TMA most commonly affects the kidneys resulting in proteinuria, hypertension and often progresses to multi-organ failure in severe cases. We previously identified in our institutional prospective study of TA-TMA a higher incidence of TA-TMA in Fanconi anemia (FA) individuals. We hypothesized that exposure to cyclosporine (CSA), which has been implicated in TA-TMA, may have led to this increase. The goal of our current study was to examine the TA-TMA incidence in FA individuals undergoing HSCT with CSA exposure at our institution and its impact on transplant related morbidity and organ function.

Methods: We performed a retrospective chart review in all patients with FA undergoing first unrelated donor T-depleted HSCT (2010-2016) using a busulfan, fludarabine, cyclophosphamide and ATG preparative regimen to identify the incidence of transplant-associated TMA and clinical outcomes. Subjects were stratified by cyclosporine use.

Results: Forty-two patients underwent unrelated donor t-depleted HSCT using busulfan, fludarabine, cyclophosphamide and ATG during the study period. Additional GVHD prophylaxis with cyclosporine (CSA) was used in the first 29 subjects while subsequent subjects received no additional prophylaxis (n= 13). Incidence of TA-TMA in the CSA and Non-CSA groups was 66% (n=19/29) and 54% (n=7/13) respectively (p=0.51) and was increased from the overall institutional TA-TMA incidence of 34% (p=0.0011). Risk factors for severe TA-TMA were increased in the CSA-group with nephrotic range proteinuria in 53% compared with 14% of the non-CSA group in tested patients and increased complement activation by sC5b-9 levels 100% vs 20%. Median duration of active TA-TMA was longer in the CSA-group at 85 days compared with 41 in the non-CSA group. Complications of TA-TMA including hypertension, kidney injury, dialysis, pericardial effusion and pulmonary hypertension were all increased in the CSA group compared to the non-CSA group.

Conclusion: Incidence of TA-TMA after HSCT is increased in FA compared to other HSCT recipients. Individuals receiving cyclosporine for GVHD prophylaxis had more severe TA-TMA than those who did not receive it, affecting transplant related morbidity and long-term renal function. Increased incidence of TA-TMA in individuals with FA may point to novel mechanisms of vascular endothelial injury. Better understanding of these mechanisms may allow for improved transplant risk stratification or new therapeutic approaches in solid tumor therapy.

Disclosures

Davies: Novartis: Honoraria.
the IKZF1-IRF4 Axis Regulates Macrophage Polarization and Macrophage-Mediated Anti-Tumor Immunity
Authors: Bruns Heiko , Mougiakakos Dimitrios , Bach Christian , Böttcher Martin , Bittenbring Joerg Thomas , Büttner Maike , Gelse Kolja , Rehli Michael , Wimmer Julia , Beier Fabian , Gezer Deniz , Krönke Jan , Balzer Heidi , Moi Stephanie , Spriewald Bernd , Mackensen Andreas , Busch Leonhard
Published: October 2019

In addition to antimicrobial activity, macrophages regulate tissue development, remodeling, and repair. In terms of neoplastic growth, tumor-associated macrophages (TAMs) are even considered pro-tumorigenic based on their angiogenic and T-cell suppressive properties. In multiple myeloma (MM) macrophages represent an abundant component of the stromal cell compartment and are believed to support proliferation, survival, and drug resistance of MM cells. Those pro-tumorigenic functions are partly instructed by T-helper (TH)-2 cytokines such as interleukin-4 (IL-4) and IL-10, which skew TAM differentiation towards an alternatively activated, or so-called M2-like, phenotype. In contrast, M1 macrophages generally considered as potent effectors in response to microbial products or interferon-γ (IFN-γ), are characterized by superior antigen-presentation, abundant production of pro-inflammatory cytokines such as interleukin-12 (IL-12), and consequently, promote a polarized type I immune response against infections as well as malignant cells. Transcriptional regulation is a key determinant for macrophage polarization. The Ikaros (IKZF1) transcription factor is critical for lymphoid development and is found in all hematopoietic progenitors as well as in T-, B-, NK-cells and macrophages. Interestingly, IKZF1 is overexpressed in MM and selectively degraded by lenalidomide, which is approved in MM therapy. The potential role of IKZF1 in modulating macrophage polarization has not been elucidated yet.

Here, we show that IKZF1expression is found highly elevated in M2-like macrophages and in MM TAMs. IKZF1 deletion in human macrophages by small interfering RNA (siRNA) or by lenalidomide yields an upregulation of M1-specific cytokines (IL-12 and IL-1b), chemokines (CXCL10 and CCL5), and costimulatory molecules (CD86 and CD40) and leads to a potent TH1-TH17 response. In fact, lenalidomide-pretreated macrophages display strong tumoricidal effects when co-cultured with MM cell lines as opposed to their untreated counterparts promoting MM proliferation and viability. Utilizing immunoprecipitation-sequencing (ChIP-Seq) we reveal that IKZF1 governs IRF4 and IRF5 expression in human macrophages. Recent studies demonstrate that IRF4 controls M2 macrophage polarization, while IRF5 regulates the M1 phenotype respectively. We could show that a lenalidomid-mediated M1-phenotype induction is efficiently abrogated by IRF4 overexpression or IRF5 silencing.

Overall, these findings unravel a novel role for IKZF1 in orchestrating macrophage polarization via the IRF4/IRF5 pathway.

Disclosures

No relevant conflicts of interest to declare.
Improved Values for Acquired Von Willebrand Syndrome and Better Clinical Outcome in Patients with Heartmate III Compared to Heartmate II
Authors: Geisen Ulrich , Brehm Kerstin , Trummer Georg , Beyersdorf Friedhelm , Berchtold-Herz Michael , Heilmann Claudia , Schelling Johannes , Schlagenhauf Axel , Zieger Barbara
Published: October 2019

Objectives: Impaired binding of Von Willebrand factor (VWF) to platelets and to collagen due to an acquired Von Willebrand syndrome (AVWS) has been observed in patients with left ventricular assist device (LVAD) support. AVWS seems to enhance bleeding symptoms in LVAD patients. The onset of AVWS occurs a few hours after LVAD implantation and affects platelet counts and function as well. The new HeartMate III (HM III) is a left ventricular assist device featuring several design-improvements that show promise to ameliorate the severity of AVWS in comparison to its predecessor, the Heartmate II (HM II). In this study, our aim was to analyze AVWS-parameters and platelet function in patients with HM II compared to patients with HM III support.

Methods: Data sets of 31 patients under HM II support and 20 patients under HM III support were analyzed pre-surgery as well as 1, 3, 7, and 30 days post-surgery. Collagen binding capacity (VWF:CB), VWF antigen (VWF:Ag) as well as VWF:CB/VWF:Ag-ratios were determined. Presence of high molecular weight multimers of VWF was investigated. Platelet counts were monitored and platelet function was tested using light transmission aggregometry.

Results: The VWF:CB/VWF:Ag ratios were significantly higher in patients with HM III than HM II at day 1, 3, and 7 after implantation. More HM III patients had intact high molecular weight multimers of VWF compared to HM II during the whole study-period (HMII: 9%; HMIII: 25%). Platelet counts and functions were comparable in both study groups. The mean duration in the Intensive Care Unit was shorter in the HM III-group than in the HM II-group (HM II: 43±52 days; HM III: 28±23 days).

Conclusion: Severity of AVWS was milder in patients with HM III compared to HM II, especially during the days after surgery, when usually most hemorrhagic events occur. Loss of high molecular weight multimers 30 days after VAD-implantation was observed in a lower percentage of HMIII-patients compared to HMII-patients suggesting a long-lasting beneficial effect. Taken together, these data show that design-improvements in the new HM III compared to the HM II result in an amelioration of AVWS that could result in lower bleeding diathesis.

Disclosures

Geisen: Roche: Research Funding. Berchtold-Herz:Novartis: Consultancy; Thoratec: Consultancy. Zieger:CSL Behring: Research Funding; Baxalta: Research Funding; Bayer: Research Funding; German Research Foundation, Bonn, Germany [ZI 486/7-1]: Research Funding.
Glutaminase Inhibitor CB-839 Enhances Proteasome Inhibitor Sensitivity in Multiple Myeloma Cells
Authors: Thompson Ravyn M. , Reyes Leticia , Smith Brittany , Dolloff Nathan G.
Published: October 2019

Multiple myeloma (MM) remains largely incurable due to the emergence of therapeutic resistance. We therefore set out in this study to identify druggable molecular mechanisms that convey resistance to proteasome inhibitors (PIs; e.g., bortezomib/VELCADE, carfilzomib/KYPROLIS), which are cornerstone agents in the treatment of MM. In comparing isogenic pairs of PI sensitive and resistant cells, we observed stark differences in cellular bioenergetics between the divergent phenotypes. While glycolysis rates between cell lines were similar, PI resistant cells exhibited increased mitochondrial respiration characterized by higher basal oxygen consumption rates (OCR) and overall respiratory capacity. Additionally, PI resistant cells were found to have lower activation of the AMP kinase (AMPK) energy stress pathway and increased levels of NAD(P)H, which serve as electron carriers in the mitochondrial process of oxidative phosphorylation. We determined that glutamine was the principle source of fuel driving mitochondrial respiration as removal of glutamine completely inhibited OCR as well as cell proliferation, whereas glucose and pyruvate were dispensable. Given the propensity for mitochondrial respiration in PI resistant cells and the dependence on glutamine for this process, we hypothesized that targeting glutamine utilization by PI resistant cells would restore their sensitivity to the cytotoxic effects of PIs. To test this possibility, we inhibited glutamine metabolism using the small molecule GLS1 inhibitor CB-839. CB-839 repressed basal OCR and total respiratory capacity and reduced cell viability to varying degrees in a panel of PI sensitive and resistant MM cell lines. Most notably, we found that CB-839 synergistically enhanced the cytotoxic activity of multiple PIs, including bortezomib, carfilzomib, ixazomib, and oprozomib, in a genetically diverse panel of 15 PI sensitive and resistant MM cell lines. The effects of CB-839 were the most apparent in combination with carfilzomib (Crflz), where it enhanced Crflz-induced death by >4-fold. CB-839 enhanced Crflz-induced apoptosis as measured by the activation of caspase 3, 7, 8 and the cleavage of the caspase-3 substrate PARP. Mechanistically, the combination of CB-839 and Crflz induces a strong and synergistic ER stress response, characterized by the induction of ATF4 and CHOP. Our findings suggest that the acquisition of PI resistance may involve adaptations in cellular bioenergetics that may be exploited therapeutically by targeting glutamine metabolism. Furthermore, our results support the combination of clinical stage compound CB-839 with PIs, particularly Crflz, for the treatment of refractory MM.

Disclosures

No relevant conflicts of interest to declare.