bluuebunny/crossref_metadata_2025 huggingface dataset:
Genome-Wide Association Study for Determinants of Acute Graft Vs Host Disease (aGVHD) After Allogeneic Hematopoietic Stem Cell Transplantation: Development of 7 SNP Model Predicting aGVHD
Authors: Park Eunkyung , Yang Song Joo , Kim Inho , Jeon Eun Hyung , Park Seonyang
Published: October 2019

Abstract 1010

Background:

Numerous studies have been reported non-HLA genetic associations with acute graft vs host disease (aGVHD) developing after allogeneic hematopoietic stem cell transplantation (allo-HSCT). So far, however, relatively few genes have been examined in each cohort. Meanwhile, aGVHD represents one of the most attractive targets to study the effect of normally silent genetic polymorphisms. We intended to elucidate genetic determinants predicting aGVHD in patients undergoing allo-HSCT by genome-wide screening of genetic polymorphisms, and develop a SNP model to predict development of aGVHD.

Methods:

Genetic polymorphisms predicting development of aGVHD were determined through successive 5 stages in a total of 429 patients who underwent allo-HSCT. Firstly, we screened genomic determinants predicting aGVHD using 109K SNP chip (Sentrix Human-1 GT Bead Chip, Illumina) in 15 patients (7 patients with aGVHD and 8 without aGVHD). At stage 2 and 3, low-density Immumina chips comprising 768 candidate SNPs and 96 SNPs, respectively, were manufactured and tested in independent cohorts of 91 patients (34 patients with aGVHD and 57 without aGVHD) and 84 patients (35 patients with aGVHD and 49 without aGVHD), respectively. At stage 4, 76 SNP chips comprising 33 SNPs discovered from the previous studies and also 43 SNPs reported to be associated with aGVHD in the literature were manufactured and evaluated in 36 patients (13 patients with aGVHD and 23 without aGVHD) undergoing allo-HSCT. Finally, 7 SNPs were chosen and validated in an independent cohort of 203 patients (50 patients with aGVHD and 153 without aGVHD) using TaqMan assay.

Results:

At stage 1, 955 SNPs were identified to be significantly associated with development of aGVHD by whole genome assay. At stage 2, candidate genetic determinants were narrowed down to 74 SNPs. Through stage 3 and 4, 7 SNPs including the two selected from the literature review (transforming growth factor beta receptor II (TGFBR2) and interleukin-18) were finally determined as predictive markers for aGVHD. The 7 SNP model was found to be effective in predicting the development of aGVHD after allo-HSCT. When decision tree model was applied, the sensitivity, specificity, accuracy, and area under ROC (AUR) of the 7 SNP model to predict aGVHD were 80.5%, 80.4%, 80.4% and 91.6%, respectively.

Conclusion:

A genome-wide association study approach was successful in elucidation of genetic determinants associated with development of aGVHD in patients undergoing allo-HSCT. The 7 SNP model was effective in predicting the development of aGVHD after allo-HSCT.

Disclosures:

No relevant conflicts of interest to declare.
Heart T2* for Prediction of Cardiac Complications in Well-Treated TM Patients
Authors: Pepe Alessia , Meloni Antonella , Rossi Giuseppe , Cianciulli Paolo , Spasiano Anna , D'Ascola Domenico , Maggio Aurelio , Maddaloni Domenico , Carollo Antonella , Rizzo Michele , Perrotta Ketty , Secchi Giuseppina , Lai Maria Eliana , Positano Vincenzo , Lombardi Massimo
Published: October 2019

Abstract 1089

Introduction:

T2* Magnetic Resonance Imaging (MRI) technique allows noninvasive quantification of organ-specific iron burden, playing a key role in the management of thalassemia major (TM) patients. There are few data on the incidence of heart failure and arrhythmias in TM patients according to baseline T2* values. The aim of this study was to establish prospectively the risk of cardiac complications in a large cohort of well-treated TM patients.

Methods:

We considered 527 TM patients (252 males, mean age 30±9) for who clinical data relative to a period of 5 years after the first MRI were collected in a central data base. At time of the first scan mean ferritin levels were1653±1559 ng/l, global heart was 27±13 ms, and excellent/good level of compliance were present in the 96% of the study population.

Results:

At 5 years of follow-up, we recorded 24 cardiac events: 4 episodes of cardiac failure, 15 of arrhythmia, 1 of pulmonary hypertension and 4 of other cardiac complications. The majority of these events (21/24) happened within the first 24 months subsequent to the MRI, so we considered this follow-up period. At the first MRI scan, in patients with cardiac complications the global heart T2* was 22.5 ±12.4 ms. In comparison with global heart T2* values ≥20 ms, there was not a significantly increased risk of cardiac complications associated with global heart T2* values <20 ms (HR= 2.028 P=0.09) (see figure). In the heart failure patients the global heart T2* was 19±12 ms. In comparison with global heart T2* values ≥20 ms, there was not a significantly increased risk of heart failure associated with global heart T2* values <20 ms (HR=1.9 P=0.524) or <10 ms (HR=2.6 P=0.443).

In the arrhythmic patients the global heart T2* was 25±13 ms. In comparison with global heart T2* values ≥20 ms, there was not a significantly increased risk of arrhythmia associated with global heart T2* values <20 ms (HR=2.1 P=0.179) or <10 ms (HR=0.8 P=0.824). During the follow up changes in the chelation therapy (type and/or dose-frequencies) were found in > 25% of the study population.

Conclusion:

We detected very few cardiac events, almost all concentrated in the first 24 months. In a large cohort of well-treated TM patients heart T2* lost its power in predicting cardiac events probably due to a patient-specific adjustment of the chelation therapy MRI-guided.

Disclosures:

No relevant conflicts of interest to declare.
Increased Expression of Secretory Leukocyte Protease Inhibitor (SLPI) In Mononuclear Cells From Patients with Deep Vein Thrombosis
Authors: Santiago-Bassora Fernanda Dutra , Barnabé Aline , Santos Andrey dos , Carazzolle Marcelo F , Pereira Gonçalo AG , de Andrade Orsi Fernanda Loureiro , de Paula Erich V , Annichino-Bizzacchi Joyce M
Published: October 2019

Abstract 1232

Deep venous thrombosis (DVT) is a common and potentially fatal condition affecting 1% to 2% of the population worldwide, with an annual incidence of 1 in 500. Several studies have demonstrated the association between inflammation and DVT. In this study, we performed a comparative analysis of gene expression from mRNA extracted from leukocytes of 20 patients with previous DVT of the lower limbs (14F/6M; mean age: 39.7 years). An array of inflammation-related genes was selected for this study. Patients were divided in subgroups: (1) spontaneous DVT (n=10; 7F/3M). (2) risk factor-associated DVT (n=6; 4F/2M), in whom risk factor included oral contraceptive, pregnancy, protein C or S deficiencies, and FV Leiden heterozigosity. (3) Patients with antiphospholipid syndrome (APS)-associated DVT (n=4; 3F/1M). Nine healthy volunteers (7F/2M) were used as controls. Using bioarray technology, 60 upregulated (UR) and 56 downregulated (DR) genes were found in DVT patients when compared to healthy volunteers. UR genes were related to immune response, inflammation and proteolysis, and DR genes were related to transcription regulation, signal transduction and inflammation. Gene expression of the SLPI, Caspase-4 precursor (CASP4), Cartilage-associated protein precursor (CRATP) and eukaryotic translation elongation factor 1 alpha 2 (EEF1A2) presented the most significant differences in expression and were then analyzed by qPCR for validation of the results. Statistical analysis was performed by the Mann-Whitney test. No significant differences were confirmed in the expression of CASP4, CRTAP and EEF1A2 between patients and controls. However, a three-fold increased in the expression of SLPI was confirmed in DVT patients compared to controls (p=0.0381). Secretory leukocyte protease inhibitor (SLPI) is synthesized and secreted by mononuclear cells to the site of inflammation in response to cytokines and TNF. Increased SLPI expression could be a result of the inflammatory response that follows DVT. SLPI, a protease inhibitor, could function as a protective mechanism that could neutralize any excess protease load and protect host tissue. Further studies to investigate the role of SLPI in the pathogeneis of DVT and its complications are warranted.

Disclosures:

No relevant conflicts of interest to declare.
Transforming Growth-Interacting Factor (TGIF) Modulates Hematopoietic Stem Cell Functions
Authors: Yan Ling , Womack Bethany , Brandt Stephen J. , Hamid Rizwan
Published: October 2019

Abstract 1279

We have shown that quantitative expression of the stem cell expressed Transforming-growth-interfering factor (TGIF) is a predictor of patient survival in acute myelogenous leukemia (AML). By Kaplan-Meier analysis, patients whose leukemic cells expressed decreased levels of TGIF RNA had a mean survival of 12 months, while patients whose leukemic cells expressed TGIF at a higher level had a mean survival of 60 months (p=0.00001).

TGIF is a homeobox transcriptional repressor and although it has been implicated in holoprosencephaly (HPE), whether it has a direct role in hematopoiesis is not known. It is known, however, that TGIF is expressed in hematopoietic stem cells (HSCs) and that it can down-regulate both TGF-b and retinoic acid (RA) signaling, and there is incontrovertible evidence that both of these pathways play an important role in hematopoiesis.

To understand the biological basis for our clinical finding, we hypothesized a role for TGIF in hematopoiesis and in particular HSC function. We then proceeded to test this hypothesis in a Tgif knockout mouse model. Flow cytometric analysis of non-lineage depleted bone marrow (BM) cells showed that Tgif-null mice had statistically increased numbers of long-term HSCs (LT-HSCs) as defined by CD34-Flk2-Lin-ckit+Sca1+ status or by CD150+CD48-Lin-cKit+Sca+ status and decreased numbers of multipotent progenitors (MPP) as defined by CD34+FlK+Lin-ckit+Sca1+ status. The short-term (ST) HSC (defined by CD34+Flk2-lin-ckit+Sca1+ or by CD150-CD48-lin-ckit+Sca+) populations were not statistically different between the null and the WT-type mice. Tgif-null BM cells produced statistically significant higher total colony number in methylcellulose colony forming unit (CFU) compared to the WT-mice though the percentages of specific colonies types remained the same. We then compared the Tgif-null BM cells with WT-BM cells in competitive repopulation assays (CRA). These experiments showed that Tgif-null BM cells were more competitive and showed higher engraftment compared to the WT-BM cells.

In conclusion, our data suggest that Tgif has an important role in hematopoietic stem cell function and may play a role in determining the balance between quiescence and self-renewal. One hypothesis to explain these data is that HSCs with no or low Tgif are more quiescent and if so this provides one biological explanation of how might TGIF affect AML prognosis; increased quiescence of HSCs or the Leukemic stem cells derived from these HSCs may make them more resistant to myelotoxic injury following chemotherapy, increasing the likelihood of relapse and/or poor long-term survival. These hypotheses continue to be an active area or research in our laboratory.

Disclosures:

No relevant conflicts of interest to declare.
Sequence Specific Single Stranded DNA Binding Protein 2 (SSBP2) Is a Regulator of Hematopoietic Stem Cell Activity
Authors: Li June , Klumpp Sherry , Amin Hesham M. , Liang Hong , Brandt Stephen J. , Nagarajan Lalitha
Published: October 2019

Abstract 1384

Interstitial deletions of chromosome 5q are common, non-random anomalies in myelodysplastic syndromes (MDS) and acute myelogenous leukemia (AML). While most deletions are large, spanning 5q13–33, a subset of patients deletes only the 5q11–14 region. We isolated SSBP2, a candidate gene from a critical region of loss at 5q14. SSBP2 expression is undetectable in AML cell lines, primary AML and MDS samples with chromosome 5q deletions. Decreased Ssbp2 expression due to viral integration has been reported in a case of primate AML resulting from HOXB4 retroviral transduction1. We have established SSBP2, to be a member of Lim Domain Binding Protein (LDB1)-Lim Only 2(LMO2)- TAL1/LYL1containing transcriptional complexes. SSBP2-LDB1, interactions promote gene expression by protecting LDB1 from proteosomal degradation2,3. LDB1-LMO2-bHLH complexes are also critical regulators of hematopoietic stem cells (HSC), a target of transformation in MDS and AML. The transcriptional cofactor LDB1 is required for hematopoiesis as part of an autoregulatory loop, which maintains the expression of TAL1, LMO2, E2A and GATA14.

Since Ssbp2 is a candidate gene from 5q and an in vivo regulator of LDB1 stability3, we sought to determine its role in hematopoietic stem cell homeostasis. In normal marrow, Ssbp2 expression is highest in Lin−, Sca1+, c-Kit+ (LSK) cells and decreases during lineage commitment. Ssbp2−/− mice are apparently normal upto six months of age although multiple hematopoitic tissues exhibit modest hypoplasia. However, hematopoietic recovery from 5-Fluoro uracil treatment is considerably delayed in these mice. Furthermore, competitive repopulation assays reveal significantly reduced short and long-term engraftment with Ssbp2−/− bone marrow. Enforced expression of Ssbp2 rescues the competitive repopulating activity. Increased expression of E2A and its' transcriptional target CDKN1A in Ssbp2−/− LSK cells appears to underlie the impaired stem cell activity. Our results identify SSBP2 to be a novel regulator of HSC function by maintaining the LDB1 mediated regulatory loop. Furthermore, these findings suggest defective stem cell homeostasis in the absence of SSBP2, when combined with mitogenic signals might contribute to the evolution of MDS/AML in a subset of patients.

Disclosures:

No relevant conflicts of interest to declare.
Prognostic Implications and Clinical Characteristics Associated with Bone Marrow Fibrosis in Patients with Myelofibrosis
Authors: Nazha Aziz , Estrov Zeev , Cortes Jorge E. , Pierce Sherry , Kantarjian Hagop M. , Verstovsek Srdan
Published: October 2019

Abstract 2824

Background:

Myelofibrosis (MF) is a heterogeneous, hematopoietic stem cell malignancy characterized by abnormal proliferation of myeloid cells with varying maturity and function. Bone marrow fibrosis (BMF), which results from abnormal deposition of stromal reticulin and collagen fibers, plays a major role in the pathophysiology of MF.

Objectives:

To investigate the characteristics associated with the extent of BMF and its implications on the clinical manifestation, overall survival (OS), event-free survival (EFS), and transformation to acute leukemia in patients with primary or secondary myelofibrosis.

Methods:

We conducted a retrospective chart review analysis of 514 patients who were diagnosed with myelofibrosis according to World Health Organization criteria (353 patients with primary myelofibrosis, 82 with post polycythemia vera [Post-PV] MF, and 79 with post essential thrombocythemia [Post-ET] MF) and were referred to MD Anderson Cancer Center between February 2005 and December 2009. Results of the first bone marrow biopsy done at MD Anderson were reviewed. BMF was documented according to the European consensus grading system (MF 0–3), in which MF-3 is the most severe grade of fibrosis.

Result:

Of 514 patients, 7 (1%) had MF-0, 44 (9%) had MF-1, 171 (33%) had MF-2, and 292 (57%) had MF-3. Table 1 summarizes patient characteristics and outcomes by grade.

Conclusion:

Severe bone marrow fibrosis was associated with lower Hgb, lower WBC count, larger spleen and abnormal cytogenetics. There was no association between JAK2 mutation and the severity of BMF. The OS, EFS and transformation to leukemia were similar among patients with various degrees of fibrosis. Similar results were achieved in patients with primary, post-PV MF, and post-ET MF. This might explain the heterogeneity of the disease course and its prognosis. Longer follow-up is needed to further investigate the impact of BMF on OS, EFS and PFS.

Disclosures:

No relevant conflicts of interest to declare.
3D Telomeric Profiles of MGUS, MMN and Relapsed MM
Authors: Olujohungbe Ade B , Klewes Ludger R , Rubinger Morel , Mai Sabine
Published: October 2019

Abstract 2899

Multiple myeloma (MM) is recognized as the second most common cancer of the blood. It is a malignant disorder of plasma cells and commonly affects adults past the age of 50. Although risk factors have been established, it is currently not possible to assess the individual risk to cancer progression. Moreover, the causes of disease progression from its precursor condition, monoclonal gammopathy of undetermined significance (MGUS), to full-blown MM and its progression to relapsed MM remain elusive. We have performed previous studies on the three-dimensional (3D) nuclear organization of telomeres and found that normal and tumor cells display significant differences in their nuclear organization. These differences were objectively quantified with two software programs, TeloView and TeloScan developed by our group.

We now report on a new double blinded preliminary study with 36 patients, including 20 MM, 12 MGUS and 4 relapsed MM. Using blood- and bone marrow-derived plasma cells from the respective patient groups, we have examined 3D nuclear telomeric profiles of the above patients. Plasma cells from MM, MGUS and relapsed MM exhibit specific 3D telomeric signatures. MM have the highest telomere numbers, followed by MGUS, while relapsed MM presents with the lowest numbers of telomeres and the shortest telomeres. Additional telomere parameters, such as cell cycle distribution profiles (a/c ratio), telomere aggregate numbers, distances from nuclear centre and also exhibited significance (p< 0.001).

Within the MGUS and MM patient groups we studied are patients whose 3D telomeric profiles indicate the beginning of a new signature that resembles signatures of MM and relapsed MM respectively. Blood and bone marrow gave us comparable results opening the future opportunity to base diagnostics and monitoring on blood samples, sparing the patient form invasive bone marrow sampling with potentially adverse effects. Based on our current preliminary data, we propose the following 3D telomeric criteria that define individual signatures of MGUS and MM and progression within each of the groups: telomere numbers, telomere sizes, presence of telomeric aggregates, telomeres per nuclear volume, and a/c ratios. The clinical significance of these findings is the early identification of individuals with high risk of progression. This opens the possibility for better monitoring and early intervention with newer treatments with an acceptable efficacy and low toxicity ratio.

Disclosures:

No relevant conflicts of interest to declare.
A Critical Population Analysis of 57, 500 US Multiple Myeloma Patients: Impact of Race, Age, and Decade of Treatment on Overall Survival
Authors: Kaya Hakan , Martincic Danko , Jawed Irfan , Peressini Ben , Elaimy Ameer L , Lee Christopher M
Published: October 2019

Abstract 2948

Background:

Recent clinical observations and published reports have suggested that there has been a significant improvement in overall survival (OS) in patients with multiple myeloma (MM) during the last decade. Previous studies have also suggested that OS was superior in younger MM patients. A large population analysis studying the impact of different races on overall survival is lacking. For this reason, we aimed to study OS differences among patients of different races. We also hypothesized that OS had already improved from the 1970s to 2000s in all MM patients due to other factors, as well as the availability of novel agents. Methods: For the years from 1973 to 2008, data on 57, 574 MM patients were obtained from the Surveillance, Epidemiology, and End Results (SEER) Program of the US National Cancer Institute. Statistical analysis evaluating patient population baseline characteristics (race, age) and year of diagnosis were performed by using univariate and multivariate Cox regression models for the OS endpoint. Results: The mean patient age at diagnosis was determined to be 68 (median = 69) years. Mean survival was determined to be 33 months (median = 21). Asian/Pacific Islander race was associated with an improved OS, HR 0.94 (CI 0.92–0.96, P <0.001). Multivariate hazard ratio analysis did not reveal any statistically significant differences in OS between patients in the white and black race (P =0.687). Younger age (age <65) was associated with improved OS when compared with patients aged 65–75 or patients aged >75 (both P <0.001). Recent treatment decades (1983–1992, 1993–2003, and 2004–2008) were associated with improved OS on multivariate analysis with HR 0.90 (CI 0.90–0.91, P <0.001), HR 0.79 (CI 0.78–0.79, P <0.001), and HR 0.71 (CI 0.69–0.74, P <0.001), respectively. Conclusions: As the largest population analysis to date, this study revealed a statistically significant improvement in OS for patients belonging to Asian/Pacific Islander race groups. In addition, MM patients from all subgroups who were treated in more recent decades, even before the availability of novel agents, exhibited superior OS. This may be due to advances in supportive care and/or earlier diagnosis, as well as an increased use of hematopoietic stem cell transplantation. With the availability of novel agents during the last decade, OS has significantly improved. Our study shows that older MM patients continued to have decreased levels OS even after the availability of novel agents. Future studies are needed to evaluate the effectiveness of novel agents in various age subpopulations.

Disclosures:

No relevant conflicts of interest to declare.
The TGF- β Family Member Growth Differentiation Factor 15 (GDF15) Regulates the Self-Renewal of Multiple Myeloma Cancer Stem Cells
Authors: Tanno Toshihiko , Merchant Akil , Agarwal Jasmin R. , Wang Qiuju , Matsui William
Published: October 2019

Abstract 2954

Multiple myeloma (MM) cancer stem cells (CSCs) possess both enhanced tumorigenic potential and relative drug resistance suggesting they play a major role in disease relapse and progression. Therefore, a better understanding of the processes regulating MM CSCs may lead to the development of novel therapies that prevent tumor regrowth and improve long-term outcomes. Normal stem cells are tightly regulated by factors within the local microenvironment that include both soluble factors and direct contact with accessory cells. However, external factors regulating MM CSCs have not been identified. Recent studies have demonstrated that stromal cells in the MM bone marrow microenvironment secrete growth differentiation factor 15 (GDF15), a member of the TGF-b family. We initially studied the role of this cytokine in the pathogenesis of MM by examining circulating GDF15 levels in MM patients. Compared to healthy volunteers, we found that median GDF15 levels were significantly increased in MM patients (821 vs. 390 pg/ml; n=16; p<0.05) and increased with disease stage (Stage II=585 pg/ml, Stage III=1, 004 pg/ml). To examine the functional effects of GDF15 on MM cells, we cultured human MM cell lines (NCI-H929, RPMI 8226) with recombinant GDF15 and found that it induced the expansion of isolated CD138neg MM CSCs in a dose-dependent manner but had little impact on the growth of CD138+ plasma cells (Fig). Furthermore, GDF15 enhanced clonogenic myeloma growth as evidenced by increased colony formation that was maintained during serial replating, a surrogate for self-renewal. This effect appeared to be GDF15 specific since it could be blocked using anti-GDF15 antibody. Similarly, GDF15 treatment increased the in vitro clonogenic growth of MM CSCs from primary clinical bone marrow specimens. We also investigated the down-stream cellular pathways potentially mediating the effects of GDF15 and found that it activates the AKT signaling pathway known to improve the self-renewal of embryonic (ES) and normal hematopoietic stem cells. GDF15 also induced expression of the SOX2 transcription factor known to be upregulated in CD138neg MM CSCs. Since SOX2 is required for the self-renewal of ES cells and the generation of induced pluripotent stem (iPS) cells, its induction by GDF15 may also increase the self-renewal of MM CSCs. GDF15 is the first soluble factor identified that regulates MM CSCs, and its effects are mediated by the activation of highly conserved self-renewal programs.

Disclosures:

No relevant conflicts of interest to declare.
Poor Mobilization of CD34+ Stem Cells Predicts Inferior Relapse and Survival Outcomes After Autologous Stem Cell Transplantation for Multiple Myeloma
Authors: Lazaryan Aleksandr , Duong Hien , Rybicki Lisa , Reu Frederic J. , Dean Robert , Sobecks Ronald , Tench Shawnda , Copelan Edward A. , Kalaycio Matt , Bolwell Brian J.
Published: October 2019

Abstract 3000

Autologous stem cell transplantation (ASCT) remains the standard upfront therapy of younger patients with multiple myeloma (MM). Identifying a prognostic threshold amount of mobilized CD34+ hematopoietic stem cells (SC) may become an important modifiable parameter in the era of novel stem cell mobilization strategies. While poor mobilization of CD34+ cells has been shown to cause delays in hematopoietic recovery, the data on long-term clinical outcomes of patients with inferior CD34+ SC collection (‘under mobilizers’) are limited. We analyzed prospectively collected data on 239 adult patients with MM who underwent ASCT at our institution from 01/1996 to 12/2009. Fifty-one patients (21.3%) who collected less than 4 × 106/kg CD34+ SC were classified as ‘under mobilizers’ and were compared to the rest of the study population (n=188) who collected ≥ 4 × 106/kg CD34+ SC. Even though under mobilizers were slightly older (median 59 vs. 54 years, p =0.01), had longer time from diagnosis to ASCT (11 vs. 8 months, p =0.05), and required more days of leukapheresis (5 vs. 3 days, p <0.001), they did not differ from the other group according to the number of prior treatment regimens, mobilization method (only 2 patients received plerixafor), performance status, or disease remission status at transplant (all p >0.2). Median time-to-recovery for both neutrophils (11 vs. 10 days, p <0.001) and platelets (13 vs. 12 days, p <0.001) was delayed among under mobilizers. Under mobilizers had worse relapse-free survival (RFS) (hazard ratio [HR]=1.49, 95% CI, 1.03–2.16, p =0.03) and non-relapse mortality (NRM) (HR=3.59, 95% CI, 1.51–8.56, p <0.01) in multivariable Cox proportional hazards analysis. Even though the association between poor CD34+ SC collection and inferior overall survival did not reach statistical significance (HR=1.42, 95% CI, 0.94–2.16, p =0.1), under mobilizers were found to have significantly higher rates of 100-day post-transplant mortality (p =0.02). We conclude that in the context of ASCT for MM, failure to collect ≥ 4 × 106/kg CD34+ SC is independently associated with worse RFS and NRM.

Disclosures:

No relevant conflicts of interest to declare.
Mesenchymal Stem Cells As a Treatment for Steroid-Resistant Acute Graft Versus Host Disease (aGVHD); A Multicenter Phase I/II Study
Authors: Ozawa Yukiyasu , Goto Tatsunori , Ohashi Kazuteru , Murata Makoto , Eto Tetsuya , Kobayashi Naoki , Taniguchi Shuichi , Imamura Masahiro , Ando Kiyoshi , Kato Shunichi , Mori Takehiko , Teshima Takanori , Mori Masaki , Muroi Kazuo , Miyamura Koichi , Ozawa Keiya
Published: October 2019

Abstract 3042

Introduction:

Allogeneic hematopoietic stem cell (HSC) transplantation is an effective therapy for a number of diseases. However, severe graft versus host disease (GVHD) remains a life-threatening complication after allogeneic stem cell transplantation, and it is very difficult to treat steroid-resistant GVHD. Mesenchymal stem cells (MSCs) have a homing activity to inflammatory sites and modulate immune response via PGE2 and so on, suggesting that MSCs might be effective for refractory aGVHD. Recently, clinical studies have suggested that MSC infusion can also reduce the severity of GVHD. We report here the results of our multicenter phase I/II study of MSCs for treatment of steroid-resistant aGVHD.

Methods:

Patients with steroid-resistant, grade II-IV, aGVHD were treated with MSCs derived from bone marrow of healthy volunteers and expanded in vitro (JR-031). MSCs were administered twice a week for 4 weeks. All patients received 2 × 106 cells/kg of MSCs for each infusion. Patients with PR after 4 weeks were given continued weekly MSCs infusion for an additional 4 weeks.

Results:

From January 2009 to November 2010, 14 patients were treated. The median age was 52 years old (range: 4–62), Male (n=5) and Female (n=9). Nine patients were diagnosed as grade II aGVHD, 5 patients were diagnosed as grade III and no patients were diagnosed as grade IV aGVHD. Thirteen of 14 patients (92.9%) responded to MSCs, achieving CR (n=8) or PR (n=5) 4 weeks after treatment. Eleven patients (78.6%) survived 24 weeks after treatment. Seven patients showed severe adverse effects including thrombocytopenia, neutropenia and hepatic dysfunction, however, no patients had severe infections which was shown by existing salvage therapy for aGVHD.

Conclusion:

The prognosis of steroid-resistant aGVHD was poor, and the most effective salvage therapy remains to be clarified. In this study, we showed that in vitro expanded MSCs, JR-031, might be a safe and effective salvage therapy for patients with steroid-resistant aGVHD.

Disclosures:

Kato: Research Grant for Tissue Engineering (H17-014) and a Research Grant for Allergic Disease and Immunology (H20-015) from the Japnese Ministry of Health, Labor and Welfare.: Research Funding.
Treatment of Steroid Resistant Grade II to IV Acute Gvhd by Infusion of Mesenchymal Stroma Cells Expanded with Human Plasma and Platelet Lysate - a Phase I/II Study
Authors: Boome Liane CJ te , Lindemans Caroline A , Slaper-Cortenbach Ineke , Rozemuller Henk , Petersen Eefke J , Boelens Jaap Jan , Bierings Marc , Wulffraat Nico , Kuball Jurgen
Published: October 2019

Abstract 3046

Introduction For numerous malignant and non-malignant hematological diseases allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative therapy. However, a major complication is the acute graft versus host disease (aGVHD), which is life-threatening and substantially reduces efficacy of HSCT. In particular, the outcome for patients with severe steroid-resistant aGVHD is very poor. Therefore, it remains important to search for new therapeutic strategies for the treatment of aGVHD.

Objective Feasibility of the generation mesenchymal stroma cells (MSCs) expanded with human plasma and platelet lysate (hPPL) was tested as well as the feasibility and safety of the application of MSCs in patients with steroid-refractory extensive aGVHD.

Method In an open-label, non-randomized prospective phase I/II study MSCs were extracted from the bone marrow of healthy volunteers, expanded with human plasma and platelet lysate (hPPL), and stored. Patients with steroid-refractory extensive aGVHD were treated with ∼2×106/kg MSC. Response rate, transplantation-related deaths, and other adverse events were assessed for up to 12 months after the last infusion of the cells.

Results Between January 2009 and December 2010, 18 patients were treated, 5 children and 13 adults, median age was 32.5 years (range 1.3–65.9). Organ involvement of the aGVHD was 67% skin, 83% gastro-intestinal and 28% liver. Overall grade was II for 4 (22%), III for 13 (72%), and IV for 1(6%) patients. 1 patient received one infusion, all other patients received two or more infusions. No patient had side-effects during or immediately after infusions of the MSC. Median follow-up was 5.5 months (range 0.33–12). Complete overall response was observed in 11 (61%) patients after a median of 65 days (range 10–184 days). The overall survival was significant better (p <0.001) compared to non-responders. Of the 11 patients who reached a CR, 8 relapsed median 59 days (1–244) after reaching CR. Three children with subsequently limited cGVHD, allo immune lung and auto-immune cytopenia and 5 adults with all relapse GVHD of the gut, median 98 days (35–302 days). However, GVHD of the gut was then sensitive for the treatment with steroids. Overall, 7 patients died, 4 due to progression of aGVHD, 1 patient due to abdominal bleeding and 2 due to sepsis.

Conclusion Generation and infusion of MSCs in steroid-resistant aGVHD grade II- IV is a feasible, safe and very effective. In addition, also patients who initially responded to MSCs but develop later a relapse of aGVHD during tapering or cessation of immunosuppressive drugs become again sensitive to the treatment with steroids.

Disclosures:

No relevant conflicts of interest to declare.
HLA DR15 Antigen Status Does Not Impact Graft-Versus-Host Disease or Disease-Free Survival in HLA-Matched Sibling Transplantation for Hematologic Malignancies
Authors: Battiwalla Minoo , Ellis Kristin , Pavletic Steven Z. , Akpek Gorgun , Hematti Peiman , Klumpp Thomas R , Maziarz Richard T. , Savani Bipin N. , Aljurf Mahmoud , Cairo Mitchell S. , Drobyski William R. , George Biju , Hahn Theresa , Khera Nandita , Litzow Mark R. , Loren Alison W. , Saber Wael , Arora Mukta , Urbano-Ispizua Alvaro , Cutler Corey S. , Flowers Mary E.D. , Spellman Stephen
Published: October 2019

Abstract 3094

The HLA class II DRB1 antigen DR15 is an important immunobiologic marker in immune mediated marrow failure states. DR15 has also been reported in small studies to be associated with favorable outcomes (reduction in acute GVHD and reduced relapse resulting in improved overall survival) after allogeneic hematopoietic cell transplant. To elucidate the impact of DR15 on major transplant outcomes, we conducted a retrospective study of 2, 891 recipients of first marrow or mobilized peripheral blood stem cell transplantation for the treatment of acute myeloid leukemia (n=1038), acute lymphoblastic leukemia (n=700), chronic myeloid leukemia (n=948), or myelodysplastic syndrome (n=205) between 1990–2008 and reported to the CIBMTR registry. Selection was confined to HLA-identical sibling transplantation to avoid HLA-disparity as a driving force for observed differences. All patients received conventional myeloablative conditioning, T-replete grafts and cyclosporine plus methotrexate- based GVHD prophylaxis. DNA-based HLA typing allowed categorization of 732 (25.3%) patients as positive and 2159 (74.7%) patients as negative for DRB1*15 :01 or *15 :02 (DR15). There were no significant differences in baseline characteristics between the HLA DR15-positive and -negative groups. In univariate analysis, HLA-DR15 status had no impact on neutrophil engraftment, acute graft-versus-host disease (GvHD) II-IV or III-IV, chronic GVHD, treatment related mortality, relapse, disease-free survival or overall survival. Confining the univariate analysis to myeloid malignancies did not alter these findings. Multivariate analysis models were constructed with DR15 status forced into the models in all steps of model building and the final model regardless of its statistical significance. Other variables tested included: donor/recipient age, CMV status, disease, disease stage, graft source, Karnofsky score, race and year of transplant. Variables that attained a p-value ≤0.05 were held in the final multivariate models. In multivariate analysis, DR15 status showed no significant difference in the primary outcomes of acute GVHD II-IV or III-IV, chronic GVHD, overall survival, or relapse. In conclusion, DR15 status had no impact on major HLA-matched sibling donor hematopoietic cell transplantation outcomes in this large and homogenous cohort of leukemia and MDS patients.

Disclosures:

No relevant conflicts of interest to declare.
Liver Specific Delivery of siRNA Targeting EGLN Prolyl Hydroxylases Activates Hepatic Erythropoietin Production and Stimulates Erythropoiesis,
Authors: Querbes William , Bogorad Roman , Moslehi Javid , Akinc Akin , Wong Jamie , Zurenko Chris , Qin June , Hettinger Julia , Kuchimanchi Satya , Charisse Klaus , Sah Dinah WY , Fitzgerald Kevin , Kotelianski Victor , Kaelin William G.
Published: October 2019

Abstract 3161

Anemia in chronic kidney disease patients due to impaired renal production of erythropoietin (EPO) and insufficient erythropoiesis is a significant public health problem. One approach to compensate for the low EPO levels in patients with impaired kidney function would be to stimulate the levels of EPO production from non-renal sources. It is well known that during fetal development the liver serves as the primary producer of EPO until the kidney becomes the dominant source after birth. Negative regulation of EPO production is mediated by the EGLN family of prolyl hydroxylases (PHDs1-3) that play an important role in oxygen sensing by targeting the transcription factor hypoxia inducible factor (HIF) for degradation via the proteasome. HIF stabilization and activity is required to mediate EPO gene transcription. Previously it has been shown that liver specific conditional knockout of all three PHDs is required to activate HIF and induce EPO production in liver (Minamishima et al. Science 2010). Here we show that simultaneous siRNA mediated knockdown of all 3 PHD genes in mouse liver using lipid nanoparticles (LNPs) can induce hepatic EPO mRNA activation, elevation of serum EPO levels and stimulation of erythropoiesis. We extend these data by examining siRNA knockdown of different combinations of the 3 PHD genes and demonstrate that PHD2 is the dominant PHD gene regulating hepatic EPO production. In addition, due to the specificity of the LNP delivery system we show that the HIF activation and increase in EPO mRNA occurs specifically in liver. Increases in serum EPO and hematocrit were durable for two weeks and one month after a single intravenous dose of LNP siRNA. Furthermore, PHD siRNA silencing in a 5/6 nephrectomy model successfully elevates hemoglobin levels and corrects anemia. In conclusion, targeting of EGLN prolyl hydroxylase genes with siRNA therapeutics has potential in the treatment of anemia associated with chronic kidney disease and provides liver-specific target gene regulation.

Disclosures:

Querbes: Alnylam Pharmaceuticals: Employment. Bogorad:Alnylam Pharmaceuticals: Research Funding. Moslehi:Alnylam Pharmaceuticals: Honoraria. Akinc:Alnylam Pharmaceuticals: Employment. Wong:Alnylam Pharmaceuticals: Employment. Zurenko:Alnylam Pharmaceuticals: Employment. Qin:Alnylam Pharmaceuticals: Employment. Hettinger:Alnylam Pharmaceuticals, Inc.: Employment. Kuchimanchi:Alnylam Pharmaceuticals: Employment. Charisse:Alnylam Pharmaceuticals: Employment. Sah:Alnylam Pharmaceuticals, Inc.: Employment. Fitzgerald:Alnylam Pharmaceuticals: Employment. Kotelianski:Alnylam Pharmaceuticals: Employment. Kaelin:Fibrogen: Consultancy, Equity Ownership.
Identification of MicroRNAs Associated with Erythropoiesis Through Deep Sequencing of Red Blood Cells,
Authors: Doss Jennifer F , Jima Dereje , An Xiuli , Dave Sandeep S. , Chi Jen-Tsan Ashley
Published: October 2019

Abstract 3164

We have recently found that human mature red blood cells (RBCs), though lacking large RNAs, possess a diverse and abundant set of microRNAs (miRNAs). MiRNAs are a class of small RNAs that inhibit translation and/or promote degradation of target mRNAs. Red blood cells are an ideal model for small RNA identification due to the relatively low amount of contaminating mRNA, tRNA, and rRNA fragments.

We performed deep sequencing of small RNAs in human RBCs to provide an unbiased set of both known and novel microRNAs, and to gain insight into the process of erythropoiesis. Small RNA libraries were applied to the Illumina GAII deep sequencing platform from both HbAA and HbSS individuals, as microRNAs have also been shown to be genetic determinants of sickle cell phenotypes (Sangokoya 2010). A modified version of the probabilistic modeling algorithm, miRDeep (Friedländer 2008), was used to identify several novel and known microRNAs. Genomic loci that overlapped with miRNAs described in miRBase were identified as known miRNAs. The remaining genomic loci were identified as encoding candidate novel miRNAs. Collectively, we identified 253 predicted miRNA precursor loci from the two samples. 226 miRNA precursor loci annotated in miRBase were identified as known miRNAs, whereas the remaining 27 precursor loci were identified as candidate novel miRNAs. In addition to miRNAs, we identified other small RNAs that did not pass miRDeep criteria. One of the most abundant sequences consisted of a distinct fragment of Ro-associated Y4 RNA (hY4). Y RNAs are involved in chromosomal DNA replication and cell proliferation, and specifically, RNAs hY1 and hY4 have been shown to be present in mature human erythrocytes (O'Brien 1990).

In addition, we also identified the relative expression of both novel and known microRNAs during erythropoiesis using both human and mouse erythroid differentiation models. We are currently investigating the relevant targets and regulatory functions of these microRNAs during erythropoiesis, as well as experimental validation of authentic microRNA fuction of novel microRNAs. This global analysis will enhance our understanding of events dictating red cell maintenance and development.

Disclosures:

No relevant conflicts of interest to declare.
Genetic Linkage of the Dehydrated Hereditary Stomatocytosis Locus to Chromosome 16 in Two Kindreds and Refinement of the Candidate Gene Region to 16q24.2 - 16qter,
Authors: Houston Brett L. , Zelinski Teresa , Houston Donald S , Israels Sara J. , Coghlan Gail , Chodirker Bernie N. , Gallagher Patrick G. , Zarychanski Ryan
Published: October 2019

Abstract 3170

BACKGROUND:

The hereditary stomatocytoses are a rare, diverse group of clinical conditions associated with chronic red blood cell hemolysis and increased erythrocyte membrane permeability to monovalent cations. The most common form of hereditary stomatocytosis is dehydrated stomatocytosis (DHSt, also called hereditary xerocytosis) first reported by Miller et al. (Blood 38:184, 1971). We studied two genetically unrelated kindreds with DHSt, one from Western Canada and the other, the original DHSt kindred reported by Miller et al., from upstate New York. Although the DHSt causative gene is unknown, previous studies have mapped the DHSt locus to 16q23 – 16qter. OBJECTIVES: To define the chromosomal region carrying the disease locus in these two families using DNA linkage analysis. METHODS: PCR-based genotyping was performed on genomic DNA according to standard methods. Fine mapping was performed using markers on the telomeric end of chromosome 16. Linkage data was generated from both paternal and maternal meioses. LOD scores (logarithm (base 10) of odds) were determined at assumed recombination fractions (theta) 0.00, 0.05, 0.10, 0.20, 0.30 and 0.40. Continuous allelic alignments were manually generated. RESULTS: Based on reticulocyte count, MCHC, and osmotic fragility, disease phenotypes were identified in 29 individuals of the Canadian kindred, and 27 individuals of the New York kindred. Linkage data from both families confirmed that the disease-causing locus mapped to chromosome 16. In the Canadian kindred, significant LOD scores (> +3.00) were established between the disease-causing locus (DHSt) and D16S3074, D16S2621 and D16S3026. Three recombinants were observed between DHSt:D16S3074, two between DHSt:D16S2621 and none between DHSt:D16S3026. Significant LOD scores were also established between DHSt and D16S3074, D16S476, and D16S413 in the New York kindred, and recombination between DHSt:D16S3074 was also observed. Definition of critical recombination events allowed us to define the centromeric boundary of the region containing the disease-causing locus as D16S2621, a 2.4 cM region containing 51 known or predicted genes. CONCLUSIONS: Genetic linkage analysis has confirmed DHSt linkage to chromosome 16 in two unrelated kindreds and has refined the assignment of DHSt to chromosome 16q24.2 – 16qter.

Disclosures:

No relevant conflicts of interest to declare.
Superiority of Haploidentical Related Hematopoietic Stem-Cell Transplantation Over Chemotherapy Alone for Patients with Intermediate- or Poor- Risk Acute Myeloid Leukemia in First Complete Remission,
Authors: Chang Yingjun , Zhu Honghu , Xu Lanping , Jiang Hao , Liu Daihong , Jiang Qian , Liu Kaiyan , Lu Jin , Jiang Bin , Huang Xiaojun
Published: October 2019

Abstract 4161

Purpose:

The role of HLA-haploidentical related donors (HRD) hematopoietic stem-cell transplantation (HSCT) in first complete remission (CR1) for adults with intermediate and poor risk acute myeloid leukemia (AML) is still not clear.

Patients and Methods:

Totally 428 newly diagnosed AML patients between 15 and 60 years old were studied between Jan 2006 and May 2010. Among 240 patients with intermediate and poor risk cytogenetics, 191patients achieved CR1 and received chemotherapy alone or HSCT as post-remission treatment. Of these, 141 patients received chemotherapy alone (n=78) or HRD HSCT (n=63) were analyzed.

Results:

Up to last follow-up time of May 2011, 44 out of 141 patients died (36 died of relapse and 8 died of TRM) and 97 patients are still alive. 49 out of 141 patients experienced relapse and 84 patients are still in continuous CR1. The cumulative incidence of relapse (CIR) at 4 years was 37.4%±4.4%. Overall survival(OS) and disease-free survival(DFS) at 4 year was 63.8%±5.0% and 55.5%±4.9%, respectively. The CIR of HRD HSCT group was significantly lower than chemotherapy group(12.8%±6.1% vs.57.4%±5.6%, p<0.0001). HRD HSCT improved survival achieved by chemotherapy alone significantly (DFS at 4 years, 71.8%±6.9% v 42.6%±6.1%, p<0.0001;OS at 4 years,75.7% ±7.0% v 54.6%±6.1%, p=0.0014). Univariate and multivariate analysis showed post-remission treatment choice (HRD HSCT or chemotherapy) and high WBC at diagnosis were independent risk factor affecting relapse, DFS and OS.

Conclusion:

HRD HSCT in CR1 is superior to chemotherapy alone for adults with intermediate and poor risk AML patients.

Disclosures:

No relevant conflicts of interest to declare.