bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of Epstein-Barr Virus Associated Central Nervous System Diseases after Allogeneic Hematopoietic Stem Cell Transplantation with Intrathecal Donor Lymphocyte Infusion
Authors: Zhao Juanjuan , Zu Yingling , Han Lu , Zhang Yanli , Gui Ruirui , Yu Fengkuan , Li Zhen , Zhao Huifang , Fang Baijun , Lin Quande , Song Yongping , Liu Delong , Zhou Jian
Published: October 2019

Allogeneic hematopoietic stem cell transplantation(allo-HSCT) is an effective measure for the treatment of hematological disease. With the progress and widespread use of allo-HSCT, Epstein-Barr virus(EBV) related central nervous system(CNS) diseases have gotten more and more attention because of its poor prognosis and overall survival. Since currently there is no standard treatment for patients with EBV-associated CNS diseases and reported therapies are heterogeneous with mixed results, we attempted to develop a novel therapeutic method. We have applied a regimen of intrathecal donor lymphocyte infusion(IDLI) in 3 patients with EBV-associated CNS diseases after allo-HSCT in addition to immunosuppressants reduction and combined antiviral therapy. All of 3 patients were responsive to this therapy: all clinical symptoms and EBV load in CSF resolved 10, 17 and 12 days after initial IDLI respectively, and magnetic resonance imaging (MRI) showed lesions of case 1 and 2 disappeared 15 and 19 days after initial IDLI respectively. Even more appealing, there were no acute or chronic adverse reactions during the infusion and up to 23 months of follow-up. In conclusion, IDLI seems to be an effective and safe method for EBV-associated CNS diseases in allo-HSCT recipients. We recommend this treatment modality for further investigation.

Disclosures

No relevant conflicts of interest to declare.
Long Noncoding RNA HOXA-AS2 As a Predictor of Acute Myeloid Leukemia: Clinical Association between HOXA-AS2 Expression and Its Role in Leukemic Cell Growth
Authors: Yan Xiaojing , Qu Yi
Published: October 2019

Long noncoding RNAs (lncRNAs) have important roles in diverse cellular processes and carcinogenesis. Homeobox (HOX)A cluster antisense RNA 2 (HOXA-AS2) is a 1048-bp lncRNA located between human HOXA3 and HOXA4 genes whose overactivation was previously found to promote the proliferation and invasion of solid tumors. However, its biological roles in acute myeloid leukemia (AML) remain unclear. This study showed that HOXA-AS2 was overexpressed in patients with AML. In addition, the increased HOXA-AS2 expression level correlated with higher white blood cell and bone marrow (BM) blast counts, unfavorable karyotype classification, earlier death, and inferior survival of patients with AML. Moreover, the results of an in vitro study showed that the silencing of HOXA-AS2 significantly inhibited the growth of leukemic cells through inducing G1/G0 phase arrest and apoptosis. In conclusion, these findings suggested that HOXA-AS2 functioned as an oncogene and might be a useful biomarker for diagnosis and prognostic prediction in patients with AML, providing a promising therapeutic target for AML.

Figure. Figure.

Disclosures

No relevant conflicts of interest to declare.
Role of N6-Methyladenosine (m6A) RNA Modification in Multiple Myeloma
Authors: Bach Christian , Leffler Magdalena , Flamann Cindy , Kronke Jan , Mougiakakos Dimitrios , Mackensen Andreas , Bruns Heiko
Published: October 2019

Multiple myeloma (MM) is considered a chronic and incurable disease due to its highly complex and heterogeneous molecular abnormalities. In recent years, integrating proteasome inhibitors and immunomodulatory drugs into MM frontline therapy has significantly improved treatment efficacy with a median overall survival (OS) being prolonged from 3-4 to 7 years. Despite this progress, patients refractory to the aforementioned agent classes display a median OS of only 9 months. Thus, the clinical necessity for developing novel therapeutic alternative approaches is self-evident.

Methylation of N6-adenosine (m6A) is known to be important for diverse biological processes including gene expression control, translation of protein, and messenger RNA (mRNA) splicing. m6A regulatory enzymes consist of "writers" METTL3 and METTL14, "readers" YTHDF1 and YTHDF2, and "erasers" FTO and ALKBH5. However, the functions of m6A mRNA modification and the specific role of these enzymes in MM remain unknown.

Here we report that METTL3, a key component of the m6A methyltransferase complex, is highly expressed in MM cell lines and in isolated patient's MM cells. In contrast, we found no significant differences in the expression of the m6A demethylases FTO and ALKBH5. Accordingly, compared to plasma cells from healthy donors, global PolyA+ RNA showed a significant increase in m6A content in patient's MM plasma cells. In MM cell lines, global m6A profiling by methylated RNA-immunoprecipitation sequencing revealed m6A peaks near the stop codon in mRNAs of multiple oncogenes including MAF and CCND1. Cross-linking immunoprecipitation showed that METTL3 bound to the m6A peak within MAF and CCND1 mRNA. Depletion of METTL3 by shRNA had little effect on global mRNA levels, but specifically reduced protein levels of c-Maf and Cyclin D1. Moreover, downregulation of METTL3 in several MM cell lines results in cell cycle arrest and apoptosis.

Together, these results describe a role for METTL3 in promoting translation of a subset of oncogenes in MM and identify this enzyme as a potential therapeutic target for multiple myeloma.

Disclosures

No relevant conflicts of interest to declare.
Inhibition of Unc-51-like Kinase 1 (ULK1) with Novel Small Molecular Inhibitor MRT68921 Preferentially Induces Apoptosis and Autophagy in FLT3-ITD- Mutated Acute Myeloid Leukemia
Authors: Jang Jieun , Jeung Hoi-kyung , Seol So-Young , Chung Haerim , Kim Yu Ri , Cheong June-Won , Min Yoo Hong
Published: October 2019

In normal karyotype acute myeloid leukemia (AML), FLT3-ITD mutation is associated with dismal prognosis with early relapse even after allogeneic stem cell transplantation. Unfortunately, to date small-molecule inhibitors of FLT3 have resulted in only partial and transient clinical responses with residual leukemic blasts acquiring resistance to FLT3 inhibitors. Therefore, elucidation of novel molecular targets should be necessary for effective eradication of FLT3-ITD AML cells. Evidences are accumulating on the functional roles of autophagy in the initiation and maintenance of AML as well as the development of drug resistance. Unc-51-like kinase 1 (ULK1) is a conserved serine-threonine kinase that plays a central role in the initiation of autophagy. Our group demonstrated that ULK1 is potentially involved in the development of resistance of AML leukemia stem cells to BET inhibitor, JQ1. The fact that ULK1 is the only conserved serine/threonine kinase in the autophagy cascade makes it a very attractive target for therapeutic development. However, the role of Ulk1 in FLT3-ITD AML remains unclear. In this study, we observed that MRT68921, a potent inhibitor of both ULK1 and ULK2, induced apoptotic cell death in FLT3-ITD-mutated AML cell lines (MV4-11, Molm13, U937/FLT3-ITD-muated) in a dose-dependent manner. However, apoptosis-inducing effect of MRT68921 was significantly lower in FLT3-WT AML (HL-60, U937). Cell death was accompanied with cleavage of caspases and PARP, which were partially blocked with caspase inhibitor z-VAD-fmk, indicating the caspase-dependent mechanism exists. MRT68921 treatment led to a notable decrease in the levels of phosphorylated (p) ATG13 (Ser 318) as well as total ULK1 and p-ULK1 (Ser 555). Interestingly, MRT68921 induced LC3-II lipidation, autophagosome, and GFP/LC3 punta formation, indicating autophagy was paradoxically activated in FLT3-ITD-mutated AML cells. AMPKa phosphorylation (T712) was increased in MTR68921-responsive cells. In contrast, autophagy induction was negligible to modest in FLT3-WT AML cells. Treatment of FLT3-ITD cells with autophagy inhibitors, 3-MA, bafilomycin A1, and hydroxychloroquine, markedly enhanced the MRT68921-induced apoptosis, strongly suggesting that prosurvival autophagy activation occurred with MRT68921 in FLT3-ITD cells. Reduction in the levels of total FLT3 and p-FLT3 protein were observed concurrently with downregulation of p-STAT5 in FLT3-ITD cells. Endoplasmic reticulum stress-associated proteins, p-PERK and p-eIF2a were also downregulated with MRT68921 in FLT3-ITD cells. Taken together, targeting the ULK1 pathway could be an effective therapeutic strategy for combating FLT3-ITD AML. Inhibition of prosurvival autophagy pathway could enhance the anti-leukemia effects of MRT68921.

Disclosures

No relevant conflicts of interest to declare.
Androgen Therapy for Lower-Risk Myelodysplastic Syndrome
Authors: Choi Eun-Ji , Lee Je-Hwan , Park Han-Seung , Lee Jung-Hee , Seol Miee , Lee Young-Shin , Kang Young-Ah , Jeon Mijin , Woo Ji Min , Lee Kyoo Hyung
Published: October 2019

Background

Improvement of cytopenia is one of the primary treatment purposes for patients with the lower-risk myelodysplastic syndrome (MDS). Androgens have been used for the treatment of aplastic anemia, immune thrombocytopenia, and telomere diseases. In this retrospective study, we aimed to evaluate the efficacy of androgen therapy in lower-risk MDS.

Methods

We analyzed the data of 139 patients who received androgens (danazol or oxymetholone) for treatment of cytopenia between February 1997 and May 2018. All patients had the international prognostic scoring system low or intermediate-1 risk at the time of androgen therapy. The assessment of hematologic improvement (HI) was based on the international working group response criteria for MDS.

Results

Androgens (oxymetholone for 83 patients and danazol for 56) were given as first (n=108, 77.7%) or over second (n=31, 22.3%)-line treatment for MDS (Table 1). The time interval between diagnosis and androgen treatment was median 1.3 months (range, 0-240.6), and 75 patients (54.0%) were red blood cell (RBC) transfusion-dependent before treatment. The dose intensity of oxymetholone and danazol was 79 and 385 mg/day respectively, and the median treatment duration was 5.8 months (range, 0.9-92.2). Seventy-nine patients (56.8%) achieved HI at any lineage: 29.0% for erythroid (HI-E), 51.9% for platelet (HI-P), and 60.5% for neutrophil (HI-N). The median time to HI following androgen therapy was 4.1 months (range, 0.6-124.5) for HI-E, 1.7 (range, 0.4-40.4) for HI-P, and 1.8 (range, 0.2-8.4) for HI-N. In univariate analysis, presence of RBC transfusion-dependence (46.7% vs. 68.8%, P=.009), pre-treatment low hemoglobin (45.2% vs. 74.5%, P=.001), high platelet count (46.5% vs. 73.6%, P=.002), and high neutrophil count (4.94% vs. 67.2%, P=.036) were associated with lower HI rate (Table 2). In multivariate analysis, pre-treatment low hemoglobin, high platelet count, and high neutrophil count remained as significant factors for lower HI rate (Table 2). During the median follow-up duration of survivors of 40.8 months (95% confidence interval [CI], 38.0-67.5), the estimated 5-year overall survival (OS) and acute myeloid leukemia-free survival was 68.8% and 67.7%, respectively. Achievement of HI was associated with longer OS (hazard ratio, 0.346; 95% CI, 0.174-0.688). There were no significant differences in HI and OS rates between danazol and oxymetholone.

Conclusion

Our data suggest that androgen can be a reasonable treatment option for lower-risk MDS patients with significant cytopenia. Prospective studies are warranted to investigate the efficacy of androgen therapy in lower-risk MDS.

Disclosures

No relevant conflicts of interest to declare.
Treatment of Relapsing/Refractory Hodgkin's Disease
Authors: Gorenkova Liliya , Kravchenko Sergey K. , Klebanova Elizaveta , Moiseeva Tatiyana , Mangasarova Yana K. , Magomedova Aminat U. , Savchenko Valery G.
Published: October 2019

Relapses of Hodgkin's disease (HD) occur in 10-15% of patients with a local tumor and in 20-40% of patients with advanced stages. A relapse of HD is early in half of the patients whereas a second remission can be achieved in only 50% of cases. Autologous hematopoietic stem cell transplantation (auto-SCT) is considered to be the standard of consolidation therapy for relapsing and primary-resistant HD. In patients with relapses of HD, progression-free survival and overall survival are 50% to 60% and 50% to 80%, respectively.

Objective. To assess the efficacy of different second-line therapies with subsequent autologous stem cell transplantation in the treatment of relapsing or refractory HD.

Materials and methods: from 2000 to 2017, 76 patients with relapsing/refractory HD treated with at least first-line therapy were involved in the study with most of the patients (70%) having received various modifications of BEACOPP regimen. The median age of patients was 27 years. A majority of participants had advanced stages of the disease: 23 (30%), 14 (18%), and 35 (46%) of patients have stage I-II, III, and IV, respectively.

Results: DHAP-regimen was given as a second-line treatment in 34 patients resulting in progression, an absence of effect, and overall response in 11 (32%), 13 (38%), and 9 of the patients, respectively. Of them, a complete remission was achieved in only 4 patients, who further underwent autologous stem cell transplantation as a consolidation treatment.

Dexa Beam regimen was given as a second-line treatment in 53 patients including those with progression after DHAP-courses. As a result, partial/complete remission, progression, and stable disease were achieved in 35 (66%), 7, and 11 patients, respectively.

Auto-SCT was carried out in 32 patients of the overall response group; 28 (88%), 3, and 4 patients have a complete long-term remission, progressive disease, and early relapses, respectively.

In the general study population, overall and event-free survival rates were respectively 86% and 71% with a follow-up median of 83 months.

Thus, Dexa Beam given as an induction treatment before auto-SCT showed an advantage in the overall response in relapsing/refractory HD. Implementation of auto-SCT as consolidation treatment after complete/partial remission has been achieved allows a long-term positive response to be attained.

Disclosures

No relevant conflicts of interest to declare.
Treatment for X-Linked Agammaglobulinemia with Allogeneic Umbilical Cord Blood Stem Cell Transplantation from HLA-Matched Sibling Confirmed Healthy through Prenatal Diagnosis
Authors: Wan Dingming , Zhang Ran , Wang Meng , Li Li , Cao Weijie , Zhang Suping , Sun Kai , Chen Xiaona , Zhang Na
Published: October 2019

Background X-linked agammaglobulinemia (XLA) is a rare congenital humoral immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19+ B-cells which was caused by mutations in Bruton's tyrosine kinase (BTK). We herein describe the first case of XLA transplanted from HLA-matched sibling allogeneic umbilical cord blood donor.

Method The patient was an 8-year-old boy with XLA who previously had life-threatening infectious episodes and diagnosed by direct sequencing of BTK gene mutations (c.992-923delGAN(NM-000061)) when he was 3 years old. He was treated with the regular replacement of immunoglobulin G (IgG) products. Taking into consideration significant infectious complications and the prompt availability of HLA-matched sibling umbilical cord blood, he underwent HLA-matched sibling UCBT. The FC conditioning regimen consisting of Flu (30mg/m2/d×4 days) and CTX (30mg/kg/d×4 days) was provided for the patient. The source of stem cells was umbilical cord blood of his younger brother who was confirmed completely healthy through prenatal diagnosis with villi at the fetus period of 4 months. The number of infused total nucleated and CD34+ cells was 6.51×108/L and 2.67×106/L, respectively. He received a combination of CsA, short-term MTX and MMF for GVHD prophylaxis.

Result Hematopoietic engraftment was rapidly achieved, with an absolute neutrophil count of >0.5×109/L on day 15 and platelet count of >20×109/L on day 20. The patient was discharged on day 45 and has been followed as an outpatient without any infectious episodes for more than 180 days. No expected toxicities were observed. Regarding immune constitution, CD19+ cells, IgA and IgM, which were undetectable before transplantation, started to increase in number 10 days after transplantation and continued to increase for more than 3 months. The patient did not exhibit any GVHD manifestations. He is currently alive and doing well at six months post-transplant, and he is free of any infection episodes.

Conclusion The above results provide strong evidence that HLA-matched sibling UCBT may be safe and technically feasible for the treatment of XLA when an appropriately matched related or unrelated donor is unavailable. The umbilical cord blood could be considered being frozen, especially in the era of "the second child" in China.

Keywords X-linked agammaglobulinemia; HLA-matched sibling donor; allogeneic umbilical cord blood stem cell transplantation; immune recovery.

Disclosures

No relevant conflicts of interest to declare.
Clinical and Hematological Risk Factors for Postpartum Hemorrhage: A 2 Years Population Based Cohort Study in France
Authors: Salomon Claire , De Moreuil Claire , Hannigsberg Jacob , Trémouilhac Christophe , Drugmanne Guillaume , Gatineau Florence , Falchier Frédérique , Briend Delphine , Abgrall Jean-François , Le Moigne Emmanuelle , Lacut Karine , Pan-Petesch Brigitte
Published: October 2019

Objective: To determine clinical and hematological risk factors for immediate postpartum hemorrhage (PPH).

Design: A cohort study.

Setting: Obstetric unit of Brest University Hospital (France).

Population: All women who underwent a vaginal delivery between April 1, 2013 and May 29, 2015.

Methods: Clinical data were collected by obstetricians or midwives during antenatal care visits, labor and delivery, and recorded by trained research assistants in a standardized electronic case report form. Hematological variables, including immature platelet fraction, were measured from a blood sample systematically performed at the entrance in the delivery room.

Main Outcome Measures: Postpartum hemorrhage (PPH), measured with a graduated collector bag, was defined as blood loss of at least 500ml.

Results: 2742 women were studied. PPH occurred in 141 (5%) women. Seven clinical factors were independently associated with PPH: pre-eclampsia (OR 5.85, 95%CI 2.02-16.90), multiple pregnancy (OR 3.28 (1.21-8.91), assisted reproduction (OR 2.75, 95%CI 1.45-5.20), ante partum bleeding (OR 2.15, 95%CI 1.24-3.73), post-term delivery (OR 1.93, 95%CI 1.17-3.17), obesity (OR 2.95, 95%CI 1.76-4.93) and episiotomy (OR 2.51, 95%CI 1.63-3.74). Three hematological factors were additionally identified as potential predictive factors for PPH: platelets < 150 000 Giga/L (OR 2.98, 95%CI 1.63-5.46), fibrinogen < 4.5 g/dL (OR 1.86, 95%CI 1.21-2.87) and APTT ratio ≥ 1.1 (OR 2.16, 95%CI 1.31-3.57).

Conclusion: Besides classical risk factors, this study highlighted the role of assisted pregnancy and obesity in the PPH occurrence, and identified simple hematological predictive risk factors for PPH. How these parameters could be integrated in a helpful prediction score of PPH remains to be determined.

Disclosures

Pan-Petesch: LFB: Other: Investigator.
Asparaginase Immune Complexes Detectable after Asparaginase-Induced Hypersensitivities Activate Basophils Via FcγRIII
Authors: Rathod Sanjay , Finkelman Fred D , Fernandez Christian
Published: October 2019

Background: Asparaginase (ASNase) is an important chemotherapeutic agent for the treatment of acute lymphoblastic leukemia (ALL). However, the development of anti-ASNase IgG antibodies are frequent, can neutralize the enzyme activity of ASNase, and can increase the risk of ALL relapse. Nevertheless, the role of anti-ASNase IgG antibodies on the onset of ASNase-induced hypersensitivity reactions is unknown, but likely require the formation of ASNase immune complexes (ICs) to activate cells involved in hypersensitivities due to the low binding affinity of the Fcγ receptor for the IgG immunoglobulin.

Objective: To detect plasma ASNase ICs after the onset of ASNase hypersensitivities and to demonstrate that binding of ASNase ICs to peripheral blood cells, and the subsequent immune cell activation, is FcγRIII-dependent.

Methods: Mice were sensitized to native E.coli ASNase using aluminum hydroxide adjuvant. ICs prepared using the plasma of sensitized mice were precipitated using polyethylene glycol to remove free ASNase and anti-ASNase IgG. ICs were detected by flow cytometry using APC labeled ASNase and protein G beads, characterized by dynamic light scattering and TEM, and the binding properties of ASNase ICs or free ASNase were determined by flow cytometry using non-sensitized and sensitized peripheral murine blood cells and the anti-IgE and/or anti-FcγRIIβ/III blocking mAb. Activation of basophils, which can occur in an IgE- or FcγRIII-dependent manner, was determined ex vivo by measuring changes in CD200R1 or CD200R3 expression after incubating peripheral blood cells with ASNase or ASNase ICs.

Results: ASNase ICs were detected after the onset of ASNase hypersensitivities in mice. ASNase ICs formed ex vivo at high anti-ASNase IgG1 concentrations, bound to naïve peripheral blood cells (e.g., neutrophils macrophage/monocytes, and basophils), and activated basophils in an FcγRIII-dependent manner. In contrast, basophil binding and activation by free ASNase was IgE- and not FcγRIII-dependent.

Conclusion: Our data indicate that ASNase sensitized mice form ICs after drug administration and can activate basophils via the FcγRIII receptor in mice, whereas the binding and activation by free ASNase occurs via cell-associated IgE. Our study suggests that ASNase ICs can contribute to the onset and severity of ASNase hypersensitivity.

Disclosures

No relevant conflicts of interest to declare.
Anti-CD30 Chimeric Antigen Receptor T Cell Therapy for CD30+ Relapsed/Refractory Hodgkin Lymphoma and Anaplastic Large Cell Lymphoma Patients
Authors: Wang Di , Xiao Yi , Li Chunrui , Wang Na , Huang Liang , Zhang Yicheng , Zhang Tongcun , Zhou Jianfeng
Published: October 2019

Chimeric antigen receptor T (CAR-T) cell therapy had shown remarkable efficacy in B-cell acute lymphoblastic leukemia and several B-cell lymphomas using CD19/22 antigen as target. Similarly, CD30 was found over-expressed on all stage of the cells in classical Hodgkin lymphoma (HL) and anaplastic large cell lymphoma (ALCL). Given the encouraging clinical success achieved by CD30 monoclonal antibody brentuximab vedotin, targeting CD30 with CAR-T cells would be a promising therapeutic approach for these populations. Here we conducted an open-label, single-center and single-arm pilot study, aimed to evaluate the feasibility and safety of anti-CD30 CAR-T cell therapy relapsed/refractory in HL and ALCL patients. This trial is registered with ChiCTR, number ChiCTR-OPN-16009069.

From August, 2016 to May, 2018, 4 HL and 2 ALCL patients with a median age of 26.5 years (range, 22-55 years) were enrolled in this study. Disease diagnosis and CD30expression was confirmed again by pathology and immunohistochemistry at enrollment. All the patients had relapsed or primary refractory disease, after at least two lines of systemic therapy. A pre-conditioning FC (fludarabin 25mg/m2, cyclophosphamide 20mg/kg for 3 days) regimen was give before CAR-T cell infusion. A total dose of 0.7-2.45×107 (median 1.175×107) per kg of CAR-T cells was infused over 3 to 7 consecutive days. The CAR transgene copy, representing CAR-T cells expansion, reached the peak at about 1 week after first administration, and then decreased. CAR transgene copy was still above 100 per μg genomic DNA in peripheral blood even 6 months after infusion. 5/6 (83.3%) patients had grade 0-1 cytokine release syndrome (CRS), with fever lower than 39℃ and duration less than 2 week. Levels of cytokines, including interleukin 6, ferritin and C-reactive protein were monitored. The maximum fold change of the cytokines from baseline was less than 10. No sign of neurotoxicity, bone marrow suppression or other adverse events were observed. The toxicity was generally tolerable, except for one HL patient, who experienced grade 4 CRS, eventually died from pneumorrhagia at the 20th day of infusion. The other 5 patients all achieved complete remission (CR) successfully. PET scan showed a CR status as early as the first month after infusion. Although relapse was observed in one HL patient 2 months after infusion, there were 3 of them remained CR state for over 1 year according to PET scan. The median progression free survival was 7 months.

In conclusion, our work demonstrated that CD30 CAR-T cell therapy is efficient and safe for HL and ALCL patients, providing a new option in treating CD30+ relapsed/refractory lymphomas, while a lager study scale was further demanded in our trial to obtain more robust support.

Disclosures

No relevant conflicts of interest to declare.
Flow Cytometric Measurement of the Initial In Vivo Response to Prednisone Provides New Prognostic Information in Childhood Acute Lymphoblastic Leukemia (ALL)
Authors: Gaipa Giuseppe , Maglia Oscar , Sala Simona , Marino Noemi , Silvestri Daniela , Valsecchi Maria Grazia , Biondi Andrea , Conter Valentino
Published: October 2019

Background The initial in vivo response on corticosteroid therapy (<1000 blasts/mmc at day 8 after exposure to Prednisone) is considered a prognostic predictor to qualify patients at higher risk of relapse (Riehm H et al, Klin. Padiat. 199, 1986). This parameter has been prospectively validated in several BFM-oriented trials providing evidences to be a robust predictor of disease recurrence even in specific subgroups of ALL (Schrappe M et al, Klin. Padiat. 2013). Evaluation of day8 prednisone response is assessed by morphological evaluation of peripheral blood (PB) smears, however this approach may have several limitations such as poor quality of the smears, operator- dependent variability and accuracy, poor reproducibility between centers.

Methods We studied a total of 543 (of 648 eligible) patients enrolled in the AIEOP-BFM ALL 2000 study between January 2001 and December 2011 in the centers of Monza and Padova (275 and 268 patients respectively). PB collected at day+8 of induction phase was analyzed by multiparametric flow cytometry (FCM) to assess blast immunophenotyping by standard methods developed in the context of the I-BFM Flow network (Dworzak MN et al, Cytometry part B, 2008).

Results Five hundred-seven patients (93.4%) had <1000 blasts/mmc as assessed by FCM, whereas 36 (6.6%) had ≥1000 blasts/mmc. Five-year Event Free Survival (5 yrs EFS) was 84.8% and 76.4% respectively (p-value =0.01). We further investigated the absolute count by sub-grouping the patients in three levels: i) 0<100 blasts/mmc (n 416), ii) ≥100<1000 blasts/mmc (n 91), and iii) ≥ 1000 blasts/mmc (n 36). 5 yrs EFS was 86.8%, 75.6% and 76.4%, respectively (p-value group a vs group b was 0.001), see Figure. Five years Cumulative Incidence of Relapse (5yrs CIR) was 11.4%, 21.1% and 17.9%, respectively (p-value group a vs group b was 0.003). When we excluded the high-risk (HR) patients from the analysis, those in the group with ≥100<1000 blasts/mmc (n71) maintained a significant worse outcome as compared with the group of patients with 0<100 blasts/mmc.

Conclusions We identified a group of 71 patients (13% of total) with non-HR characteristics and with ≥100<1000 blasts/mmc at day8, showing significant worse outcome as compared to patients with <100 blasts/mmc, that could benefit of a more intensive treatment. These Analyses will be validated on a larger cohort of patients. FCM is more accurate and reproducible as compared to morphology and should be considered as an alternative method for the evaluation the initial in vivo response to corticosteroid therapy and possibly for a further refinement of treatment stratification of children with ALL.

Figure. Figure.

Disclosures

No relevant conflicts of interest to declare.
Proteomic and Biological Analysis of Myeloma Cell Derived Extracellular Vesicles
Authors: Hoelzinger Dominique B , Quinton Sophia J , Walters Denise K , Tschumper Renee C , Jelinek Diane F
Published: October 2019

Intercellular communication between multiple myeloma (MM) cells and the normal bone marrow stroma leads to a modification of the bone marrow microenvironment, which favors tumor progression. New developments in extracellular vesicle (EV) research suggest that this diverse population of vesicles, released by cancer cells including MM cells, express transmembrane proteins and carry cargo that can modify recipient cells in myriad ways. In particular, tumor-derived EVs have been shown to create permissive microenvironments that lead to metastatic colonization by circulating tumor cells. As we have previously shown that MM EVs can enhance proliferation of recipient MM cells, we hypothesize that MM EVs can potentially play a much larger role in MM development and progression. In order to understand the scope of potential EV roles in MM, we executed a comprehensive proteomic analysis of the cargo of MM EVs. We isolated EVs from patient derived MM cell lines that represent the most common genetic variants of this tumor, and used in vitro generated plasma cells (IVPCs) as a reference population. In a first pass analysis, we selected proteins that were expressed ≥3 fold higher in MM EVs than in IVPC EVs, and this analysis identified 306 proteins. Of interest, included in the 306 differentially proteins were several involved in the regulation of cell adhesion such as members of the a disintegrin and metalloprotease domain (ADAM8, 9, 10, 13, 15 and 22) family, which are also associated with inhibition of cell proliferation. Moreover, CEACAM1, PTPRK, and CDH2, which are also linked to cellular adhesion, were also expressed at a higher level in MM EVs. Various proteins linked to myeloma cell biology were likewise found to be over-represented in MM EVs, and these include BCMA, ITGAV, ITGB5, IL6ST (gp130), CD276 (B7-H3), and CD28. As we are most interested in biologically relevant and actionable proteins present uniquely in MM derived EVs, we filtered from our data proteins that were also present in EVs from IVPCs. We further filtered out proteins known to be present in EVs from normal cells. This filtering strategy reduced the number of interesting candidates to 8, which included CD28, MET, TRKC, and ADAM15. Thus far, we have confirmed the presence of these 4 proteins in a panel of MM EVs, and we are currently in the process of validating additional candidate cargo proteins for their biological role in enhancing tumor cell proliferation and/or protection from apoptosis. In summary, EV proteomic analysis of cell lines representing MM genetic subtypes can lead to the identification of biologically relevant proteins transported systemically by EVs as well as suggest novel biomarkers that are easily detectable in plasma and may permit earlier recognition of disease progression in patients with MM.

Disclosures

No relevant conflicts of interest to declare.
Evaluation of the Risk of Atrial Fibrillation/Flutter Among Patients Initiating Ibrutinib
Authors: Nohria Anju , Rosenblatt Lisa , Pan Xianying , Sharma Arpita
Published: October 2019

INTRODUCTION:

Ibrutinib is a Bruton's tyrosine kinase inhibitor that is used to treat chronic lymphocytic leukemia and other hematologic malignancies. Atrial fibrillation/flutter (AF) is emerging as an adverse effect of ibrutinib therapy. The objective of this analysis was to evaluate the incidence of new AF in a real-world sample of patients initiating ibrutinib and exploring potential risk factors of AF in this population.

METHODS:

A retrospective cohort study of patients (age>=18) initiating ibrutinib between 01 Nov 2013 and 30 Sep 2017 was conducted using four US administrative claims databases. The databases used were MarketScan - Commercial and Medicare Supplemental Database, Optum Clinformatics Data Mart, PharmetricsPlus Adjudicated Claims Database and Humana. Patient cohorts were identified independently from each of the databases and were combined for pooled analyses after ensuring a minimum patient overlap of less than 5% among databases. The date of first prescription of ibrutinib was considered as the index date. Patients were followed from the index date to the end of index ibrutinib therapy (ibrutinib discontinuation date, follow-up end, or study end, whichever was earliest) to identify the diagnosis of new AF. Patients with an AF diagnosis prior to the index date were excluded. Baseline characteristics (including demographics, comorbidities, type of cancer and Charlson Comorbidity Index (CCI) score) were evaluated. Incident rates were calculated as number of AF events per 100 person-years and were stratified by age and gender. Cox regression models were used to estimate hazard ratios and assess potential risk factors for AF among patients receiving ibrutinib.

RESULTS:

The study examined outcomes in 7,276 patients treated with ibrutinib, including 4,650 (63.91%) males and 2,626 (36.09%) females, followed for a median duration of 161 days (~5.3 months). The overall incidence rate of AF was 12.5 per 100 person-years (Table 1). The median duration until AF diagnosis was 117 days (~4 months). Males were at higher risk of developing AF than females; a similar trend was observed in patients age >75 compared to younger patients. Ibrutinib patients with congestive heart failure (CHF), peripheral vascular disease (PVD) or a moderate CCI score (3-4) at baseline were at higher risk of developing AF.

CONCLUSION:

The incidence of AF in patients treated with ibrutinib is substantial. Older age, male gender, and baseline comorbidities (CHF and PVD) notably affect the risk of developing AF in these patients. AF should be considered when monitoring for adverse events in patients treated with ibrutinib.

Disclosures

Nohria: Takeda Oncology: Consultancy; Amgen: Research Funding. Rosenblatt:Bristol-Myers Squibb: Employment, Equity Ownership. Pan:Bristol-Myers Squibb: Employment, Equity Ownership. Sharma:Mu Sigma: Employment; Bristol-Myers Squibb: Consultancy.
Impact of Length of Stay on Hospital-Associated Venous Thromboembolism (VTE)
Authors: Slostad Jessica A , Slostad Brody , Crusan Daniel , Petterson Tanya , Bailey Kent , Ashrani Aneel A. , Heit John A.
Published: October 2019

Introduction:

Hospitalization-associated VTE attack (incident plus recurrent VTE) rates over the 6-year period, 2005-2010, did not change significantly despite achieving near-universal in-hospital VTE prophylaxis; 75% of these VTE events occurred after hospital discharge with a median of 19.5 days from hospital discharge to VTE. The median durations of hospitalization and in-hospital prophylaxis were 3 days and 70 hours, respectively, suggesting that VTE prophylaxis was inadequate. However, the hospital population that would benefit most from post-hospitalization VTE prophylaxis is uncertain. Our study aim was to test hospital length of stay (LOS) as a potential predictor of post-hospital-discharge incident or recurrent VTE.

Methods:

Using the resources of the Rochester Epidemiology Project, we identified all unique Olmsted County, MN residents hospitalized at least once at a Rochester, MN Mayo Clinic hospital and all such residents with objectively-diagnosed occurrence of first or recurrent VTE during hospitalization or within 92 days after hospital discharge, 2005-2010. We tested LOS as a potential predictor of post-hospital-discharge VTE (conditional on surviving to hospital discharge free of VTE) using the Anderson-Gill version of Cox regression modeling and adjusting for age, sex, any surgery performed during that hospitalization, and Charlson Comorbidity Index calculated from conditions recorded from 1/1/2005 until the day of hospital discharge.

Results:

Over the period, 2005-2010, 31,588 unique Olmsted County residents were hospitalized at least once at a Rochester Mayo Clinic hospital. The distribution of LOS was: 1-2 (3.8%), 3 (24.2%), 4 (23.3%), 5 (16.4%), 6 (8.8%), 7-9 (12.4%), 10-19 (8.4%) and 20+ (2.3%). Of the 253 VTE events identified within 92 days post-hospital discharge, 6, 29, 31, 38, 38, 53, 42 and 16 had been hospitalized for 1-2, 3, 4, 5, 6, 7-9, 10-19 and 20+ days, respectively. The hazard ratios (HR) for post-hospital-discharge VTE were similar for hospital LOS ≤4 days; compared to LOS ≤3 days, the HRs were significantly increased for hospital LOS of 5 (HR=1.78), 6 (HR=2.86), 7-9 (HR=2.71), 10-19 (HR=3.16) and 20+ (HR=4.20) days (Table 1).

Conclusions:

The adjusted hazards of post-hospital discharge VTE for hospital LOS > 4 days were significantly increased 1.8 to 4.2-fold compared to LOS ≤3 days, suggesting that hospital LOS may be useful for identifying hospitalized patients suitable for longer duration VTE (including post-discharge) prophylaxis. Future studies should be aimed at identifying additional predictors of post-hospital-discharge VTE such that extended prophylaxis can be targeted to those patients who would benefit most.

Disclosures

No relevant conflicts of interest to declare.
Targeting the MTF2-MDM2 Axis Sensitizes Refractory Acute Myeloid Leukemia to Chemotherapy
Authors: Jrade Hani , Maganti Harinad B , Cafariello Christopher , Porter Christopher J , Yockell-Lelièvre Julien , Battaion Hannah L , Khan Safwat T , Howard Joel P , Perkins Theodore J , Sabloff Mitchell , Ito Caryn Y , Stanford William L.
Published: October 2019

Next generation sequencing of acute myeloid leukemia (AML) patient samples has enabled more granular risk stratification of patients; however, refractory AML patients can be found across all risk groups, suggesting that non-genetic lesions regulate chemoresponsiveness. Consistent with this hypothesis is the finding that many of the mutated AML driver genes are encode epigenetic modifiers. Thus, unraveling the epigenetic dysregulation in AML is critical to better understand disease initiation and progression, as well as develop targeted therapies. Metal Response Element Binding Transcription Factor 2/Polycomblike 2 (MTF2/PCL2) plays a fundamental role in recruiting the Polycomb repressive complex 2 (PRC2) to chromatin and we show that it is commonly silenced in primary AML patient cells at diagnosis. Furthermore, the loss of MTF2 in hematopoietic stem and progenitor cells (HSPCs) leads to an altered epigenetic state that underlies refractory AML. By implementing unbiased systems analyses, we identified the E3 ubiquitin ligase MDM2 that inhibits p53 as a direct target of MTF2-PRC2. MTF2 deficiency leads to over-expression of MDM2 and inhibition of p53-mediated cell cycle regulation and apoptosis, leading to chemoresistance and refractory AML. Targeting this dysregulated signaling pathway by MTF2 overexpression or MDM2 inhibitors sensitized refractory patient leukemic cells to induction chemotherapeutics and prevented relapse in AML patient-derived xenograft (PDX) mice. Therefore, we have uncovered a direct epigenetic mechanism by which MTF2 functions as a tumor suppressor required for AML chemotherapeutic sensitivity and identified a potential therapeutic strategy to treat refractory AML.

Disclosures

Sabloff: Celgene: Membership on an entity's Board of Directors or advisory committees.
Incidence, Clinical Characteristics and Outcome of Cardiac Toxicity in Elderly Patients with Diffuse Large B-Cell Lymphoma
Authors: Liu Wei Ping , Xu Yan Feng , Xie Yan , Wang Xiaopei , Song Yuqin , Zhu Jun
Published: October 2019

Backgroud:

Cardiac toxicity is a life-threatening complication in elderly patients with lymphoma, which lead to a delay or premature termination of chemotherapy.

Methods:

A total of 462 consecutive patients with diffuse large B-cell lymphoma over 60 years old between 2007 and 2017 were reviewed. Of these, 87 patients were excluded from the study. Finally, 375 lymphoma patients were included. Data about general information, clinical feature, laboratory examination, pathological results, therapeutic methods and cardiac toxicity were collected by case retrieval system. Cardiac toxicity was graded according to National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE).

Results:

The incidence of cardiac disorders was 5.3% (20/375). The median number of chemotherapy cycles before cardiac toxicity was 1 (range, 1-4). Ventricular arrhythmia was the most frequent cardiac disorder (n=6), followed by palpitations (n=4), left ventricular systolic dysfunction (n=3), heart failure (n=3), atrial fibrillation (n=2), myocardial infarction (n=1) and paroxysmal atrial tachycardia (n=1). At the end of treatment, grades 3 to 5 cardiac events were observed in 8 patients. In a multivariate Cox regression analysis, ECOG performance status ≥2 and history of cardiovascular disease were identified as risk factors for IP. The cumulative incidence of cardiac disorders were 2.3% (6/266) for patients without risk factors, 11.6% (11/95) for patients with 1 risk factors, and 21.4% (3/14), respectively.

Conclusion:

Cardiac toxicity is not rare in elderly patients with lymphoma, and a comprehensive management strategy is needed.

Disclosures

Song: Peking University Cancer Hospital (Beijing Cancer Hospital): Employment. Zhu:Beijing Cancer Hospital: Employment.
Compound Heterozygous Nonsense Mutations Leading to Hereditary Deficiency of Coagulation Factor XI in a Chinese Pedigree
Authors: Li Qian , Zeng Hui , Xu Yong , Zhou Min , Chen Bing , Zhou Rong-Fu
Published: October 2019

The objective is to identify the gene mutations responsible for the deficiency of factor XI (FXI) in a Chinese pedigree. The FXI activity was tested with clotting assay. The F11 gene was amplified by PCR with direct sequencing. ClustalX-2.1-win and three online bioinformatics softwares were used to study the conservatism and harm of the mutation. The proband was a 70-year-old male and had a prolonged APTT of 67.8s. The corrected APTT was 28.3s and he had reduced FXI: activity of 0.8%. His son and daughter had normal APTT of 26s and 27.3s and FXI:C of 72% and 75%, respectively. DNA sequencing analysis showed the proband carried a compound heterozygous g.841C>T and g.1556G>A mutation , resulting in Ser281Stop and Trp519Stop, respectively, which caused premature termination of transcription in the F11. His son had the heterozygous g.841C>T mutation of F11 and his daughter had the heterozygous g.1556G>A mutation of F11. The three bioinformatics softwares indicated that the mutation had affected the function of the protein. The two nonsense mutations had been reported previously in different patient, but this is the first time to be reported in the proband, which was responsible for the decrease of FXI: activity.

Disclosures

No relevant conflicts of interest to declare.
98% IGHV Gene Identity Is Still the Optimal Cutoff to Predict the Prognosis of Chronic Lymphocytic Leukemia Patients in China
Authors: Xia Yi , Shi Ke , Sun Qian , Qiao Chun , Zhu Huayuan , Wang Li , Fan Lei , Xu Wei , Li Jianyong
Published: October 2019

Background: Immunoglobulin heavy chain variable region (IGHV) has been an important prognostic factor for chronic lymphocytic leukemia (CLL) for decades. 98% being a cut-off value for IGHV is a mathematical choice and researches on the best cut-off value have never been stopped. Chinese CLL patients are known to differ from Caucasian CLL patients on both clinical and genetical features. However, the optimal cutoff for IGHV mutational status has not yet been studied in this particular ethnic group.

Method: We carried out a study on 595 Chinese CLL patients in order to find out whether 98% is the best cut-off value for IGHV in Chinese CLL patients. Genomic DNA from peripheral blood or bone marrow was subjected to PCR amplification following the IGH Somatic Hypermutation Assay v2.0 protocol (InVivoScribe). Sequences were aligned to ImMunoGeneTics/V-QUEry and Standardization (IMGT/-VQUEST) database.

Result: 600 sequences were received after IGHV rearrangement sequencing. IGHV3-23, IGHV4-34, IGHV3-7, IGHV4-39 and IGHV1-69 were the most frequently used IGHV genes. 352 (58.7%) cases were IGHV-mutated while 248 (41.3%) cases were IGHV-unmutated if the classical 98% classification by ERIC was used. In order to determine the optimal cut-off value, we used 1% as the interval to divide the entire cohort into 7 groups according to the mutational rate, which were <95%, 95%-95.99%, 96%-96.99%, 97%-97.99%, 98%-98.99%, 99%-99.99% and 100% respectively. Binet A patients had a relatively indolent course of disease and cases with different IGHV mutational rates had no significant differences in time to first treatment (TTFT) apart from truly unmutated (100%) cases. For the whole study cohort, significant difference appeared at 98% interval (P<0.001 and P=0.005 for TTFT and OS respectively) while intervals less than 98% had no significant difference compared with the <95% group. Similarly, there was no clear dissimilarities among 98%, 99% and 100% intervals (Table 1a and b). All the other prognostic factors including del(17p), del(11q), TP53 mutation, MYD88 mutation, NOTCH1 mutation, SF3B1 mutation, CD38, ZAP-70, Binet staging, gender, β2-microglobulin and EBV-DNA were differently distributed between group <98% and group ³98%, but not among subgroups in ³98%. In multivariate analysis, the 98% IGHV was also an independent prognostic factor for TTFT and OS.

Conclusion: 98% is the optimal cutoff value for IGHV mutational status to predict the prognosis of CLL patients in China.

Table 1. Table 1.

Disclosures

No relevant conflicts of interest to declare.
Predictors of Adverse Outcome in Sickle Cell Disease Patients from Oman
Authors: Alkindi Salam , AlJadidi Salma , Al Adawi Safa , Pathare Anil
Published: October 2019

Introduction: Sickle cell disease (SCD) is a major public health problem in Oman with high morbidity and mortality. The ability to identify the risk factors that are associated with mortality among SCD patients would permit accurate prognostication and provide an opportunity to use effective prophylactic management.

Objective: The study aimed at identifying the risk factors associated with mortality in SCD patients by studying the clinical course of 86 patients who died at two tertiary care hospitals in Oman.

Methods: We analyzed the electronic records of 86 SCD patients who died between 2006 to 2016. These data included cardiac parameters, SCD manifestations like frequency of painful crisis, acute chest syndrome, splenic and hepatic sequestration, dactylitis, and stroke. Furthermore, we also analyzed the haematological, biochemical and radiological parameters as well as use of antibiotics and exchange blood transfusion. Data were transcribed to Excel and later analyzed by IBM SPSS Ver23.

Results±13.7. Previous complications prior to death included acute chest syndrome in 66.3% cases, followed by stroke in 20.9%, hepatic sequestration in 6.9%, splenic sequestration in 3.5% and dactylitis in 2.3% cases. At the terminal event, patients presented with fever, cough and crepitation in 47%, 29% and 36% respectively, while abnormal pulse, blood pressure, respiratory rate and O2 saturation were seen in 55%, 64%, 46% and 55% respectively. Further abnormal chest x-ray, CT scan and abdominal ultrasound were seen in 57.5%, 88.5% and 50% respectively. Amongst the haematology parameters, there was a significant drop in the mean hemoglobin and platelet counts from baseline, whereas there was a significant rise in the WBC counts (p<0.05, student's t test). The biochemical parameters showed a significant rise in the LDH and CRP levels (p<0.05). All patients received antibiotics, 88% received blood transfusions, 35.7% received exchange transfusions, whereas 87.5% required NIV/ventilation. Finally, all patients presented with multi-organ terminal events that varied in the severity, but sepsis showed the commonest cause of death (54.3%).

Conclusion: Multi-organ failure was mostly associated with the terminal events relating to mortality. Although sepsis played a major role as a cause of death in association with multiorgan failure, low hemoglobin, and low platelet counts with increased WBC counts along with elevated LDH and CRP played a significant role in the terminal event in this cohort of SCD patients.

Disclosures

No relevant conflicts of interest to declare.