bluuebunny/crossref_metadata_2025 huggingface dataset:
Calcineurin Inhibitors Replacement By Ruxolitinib As Graft Versus Host Disease Prophylaxis for Patients after Allogeneic Stem Cell Transplantation
Authors: Zhao Yanmin , Huang He
Published: November 2019

Severe graft versus host disease (GVHD) is a leading cause of morbidity and mortality after allogeneic stem cell transplantation (allo-SCT). Currently, the most widely used prophylaxis regimen usually includes calcineurin inhibitor (CNI; i.e., tacrolimus and cyclosporine). However, the incidence of aGVHD is about 30%-50%, and a minority of patients have contraindications against CNI. Thus, improved GVHD prevention methods are still needed. This study aimed to determine the prophylactic value of ruxolitinib for graft versus host disease (GVHD) in calcineurin inhibitor (CNI)-intolerant patients after allogeneic stem cell transplantation (SCT). From September 2017 to March 2019, 10 patients intolerant to CNI were enrolled. The regimens were based on the myeloablative BuCy regimen. Thymoglobulin 6 mg/kg was applied to patients with HLA-haploidentical related donors (HRD). All received ruxolitinib to replace CNI as GVHD prophylaxis. Ruxolitinib was initiated at 5-10 mg twice daily, maintained for 2-3 months, and then tapered gradually. Eight patients had acute leukemia, one had myeloproliferative neoplasm, and one had natural killer T-cell (NK/T-cell) lymphoma. The donors were from matched sibling donors (MSD, n = 3) and HRD (n = 7). They received CNI plus short-time methotrexate as GVHD prophylaxis, but all showed intolerance within 45 days after SCT due to transplantation-associated thrombotic microangiopathy (n = 4), CNI-induced pain syndrome (n = 2), and CNI-related renal/hepatic dysfunction (n = 4).After ruxolitinib replacement, only one patient (10%) developed grade II skin aGVHD within 100 days, and only one developed severe aGVHD after 100 days. Among nine patients who survived beyond day +100, two (2/9, %) developed moderate/severe cGVHD after tapering or stopping ruxolitinib, resulting in 1-year accumulative incidence of moderate/severe cGVHD of 23.8%. Cytomegalovirus reactivation occurred in four patients (40%). After a median follow-up of 10.5 (range: 2-14.5) months, two out (20%) relapsed, and seven (70%) were alive in good condition, of whom six (60%) maintained negative MRD.This study showed that the prophylactic application of ruxolitinib for CNI-intolerant patients after allo-SCT was effective in preventing GVHD, with a mild side effect.

Disclosures

No relevant conflicts of interest to declare.
The Fanconi Anemia-Associated Protein NIPA Is Essential for the Nuclear Abundance of FANCD2
Authors: Kreutmair Stefanie , Erlacher Miriam , Andrieux Geoffroy , Istvanffy Rouzanna , Rudorf Alina , Zwick Melissa , Rückert Tamina , Pantic Milena , Poggio Teresa , Shoumariyeh Khalid , Müller Tony Andreas , Kawaguchi Hiroyuki , Follo Marie , Klingeberg Cathrin , Wlodarski Marcin , Baumann Irith , Pfeifer Dietmar , Kulinski Michal , Rudelius Martina , Lemeer Simone , Kuster Bernhard , Dierks Christine , Peschel Christian , Cabezas-Wallscheid Nina , Duque-Afonso Jesus , Zeiser Robert , Cleary Michael , Schindler Detlev , Schmitt-Graeff Annette , Boerries Melanie , Niemeyer Charlotte M. , Oostendorp Robert A.J. , Duyster Justus , Illert Anna Lena
Published: November 2019

Inherited bone marrow failure syndromes (IBMFS) are a heterogeneous group of disorders characterized by impaired stem cell function resulting in pancytopenia. Diagnosis of IBMFS presents a major challenge due to limited diagnostic tests and overlapping phenotypes. For that reason, novel and clinical relevant biomarkers and possible targets are urgently needed.

Our study defines NIPA as an IBMFS gene, which is significantly downregulated in a distinct subset of MDS-type refractory cytopenia of childhood patients. Mechanistically, NIPA binds FANCD2 and regulates its nuclear abundance. The stabilization of both non- and monoubiquitinated FANCD2 identifies NIPA as an essential player in the Fanconi Anemia (FA) pathway. NIPA thereby prevents MMC hypersensitivity visualized by increased numbers of chromosome radials and reduced cell survival after induction of interstrand crosslinks. To provide proof of principle, re-expression of FANCD2 in Nipa deficient cells restores MMC sensitivity. In a knockout mouse model, Nipa deficiency leads to major cell intrinsic long-term repopulation defects of hematopoietic stem cells (HSCs), with impaired self-renewal in serial transplantations and a bias towards myeloid differentiation. Unresolved DNA damage in Nipa deficient HSCs causes increased sensitivity to cell death and leads to progressive, age-related loss of the HSC pool. Induction of replication stress triggers the phenotypic reduction and functional decline of murine HSCs, resulting in complete bone marrow failure and death of the mice thereby mimicing Fanconi Anemia.

Taken together, our study adds NIPA to the short list of FA-associated proteins being essential for a functional DNA repair/FA/BRCA axis and thereby emphasizing its impact as potential diagnostic marker and/or possible target in bone marrow failure syndromes.

Disclosures

Niemeyer: Celgene: Consultancy.
Ten Years of Treating Chronic Myeloid Leukemia in Rural Rwanda: Feasible Approaches for Low-Resource Settings
Authors: Morgan Jennifer , Bigirimana Jean Bosco , Nguyen Cam , Deboer Rebecca , Shyirambere Cyprien , Paciorek Alan , Lehmann Leslie E. , Shulman Lawrence N.
Published: November 2019

Objective: To describe the characteristics and outcomes of chronic myeloid leukemia (CML) patients treated through the Glivec Patient Assistance Program (GIPAP) in Rwanda.

Methods: We retrospectively reviewed all BCR-ABL positive CML patients treated with imatinib at two rural hospitals between 2009 and 2018. Clinical data were analyzed using descriptive statistics, Kaplan-Meier method, and proportional hazards regression.

Results: One hundred twenty-four patients were included; median age 35 (range: 9-81), 60% male, 88% without comorbidities. All patients presented with symptomatic disease, median duration 11 months (IQR: 4-24) and median WBC count 225.5 x 109/L (IQR: 117.7-308.5). At diagnosis, 71% were in chronic phase. On imatinib, 91% achieved complete hematologic remission (CHR); 67% within 90 days. Of those who achieved CHR, 51 (45%) lost it at some point and, of which, 36 (71%) regained CHR. At four years, overall survival was 79% (95% CI:69%-86%) for the entire cohort; 93% (95% CI: 79%-98%) for 53 patients who remained in CHR, 89% (95% CI: 69%-96%) for 34 patients who lost but regained CHR, 19% (95% CI: 1%-54%) for 12 patients who lost and never regained CHR. Never achieving CHR was associated with increased mortality (HR: 40.89; 95% CI: 9.88-169.32; p<0.001) as was losing CHR without regaining it (HR 15.73; 95% CI: 4.14-59.81; p<0.001) compared to never losing CHR.

Conclusions: Here we demonstrate the feasibility of coupling molecular diagnostics with chronic targeted therapy in a rural low-resource setting through health systems strengthening and international collaboration. Our CML patients are younger, slower to achieve CHR with imatinib, and have higher rates of primary and early hematologic resistance than historical cohorts, suggesting biological differences that warrant further investigation. It is uncertain what role non-adherence to medication influences these data. Without molecular response assessment, hematologic response is an accurate marker of disease control and survival. Our imatinib failure rates highlight the need for access to resistance testing and second generation tyrosine kinase inhibitors, as well as adherence rates.

Disclosures

No relevant conflicts of interest to declare.
Metabolomic Profile in Patients with Paroxysmal Nocturnal Hemoglobinuria
Authors: Yamakawa Patricia Eiko , Da Fonseca Ana Rita , Vescovi Matheus , Gomes Iara Baldim Rabelo , Guerreiro da Silva Ismael Dale Cotrim , Arrais-Rodrigues Celso
Published: November 2019

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is a non-malignant clonal disease of hematopoietic cells with a complex pathophysiology and variable clinical spectrum, characterized by signs and symptoms related to intravascular hemolysis, hypercoagulability, and cytopenias. Metaboloma is the end product of an organism's genetic configuration plus the influence of all factors to which it is exposed. Metabolomic profile is able to provide a more accurate functional measure of a phenotype formed by the result of genomic, transcriptomic and proteomic changes.

Aims: To compare a metabolomic profile in the PNH hemolytic group with healthy controls, and to compare a metabolomic profile before and after the administration of eculizumab in PNH patients.

Methods: To perform metabolomic profile, we used mass spectrometry in 23 patients with hemolytic PNH and in 166 healthy adults, as control group. Twelve PNH patients samples were also collected before and 24 hours after receiving eculizumab. Liquid chromatography with mass spectrometry was performed using the AbsoluteIDQ P180 Biocrates kit (Biocrates, Life Science AG, Innsbruck, Austria): 186 metabolites from 7 different classes were identified and quantified. The data were imported to the analytical site MetaboAnalyst 4.0 and ROCCET: ROC Curve Explorer & Tester for the generation of Univariate and Multivariate Operational Characteristic curves of the Receiver (ROC).

Results: In the patients with hemolytic PNH, of the 186 metabolites analyzed, 92 of them showed significant differences between patients and controls, with positive or negative correlation. The major metabolites increased in the PNH group were long-chain acylcarnitines, while the major metabolites reduced in the PNH group were histidine, taurine, glutamate, glutamine, aspartate and phosphatidylcholines. The C14:1/C16:1 ratio lower than 1.4 was shown to be a reliable marker in patients with PNH, suggesting a disorder in lipid elongation. Besides, PNH patients had a significant increase in C6:1 levels and C14:1/C6 and C4/C6 ratios. After receiving eculizumab, patients reached levels comparable to those of normal subject.

Conclusion: We observed differences in the metabolome of PNH patients as compared to healthy controls, suggesting a unique metabolomic profile of these patients, characterized by an altered acylcarnitine balance, reduction in aminoacids participating in the glycogenesis pathway and an impaired glutaminolysis. Acylcarnitines levels seem to significantly reduce with the use of eculizumab, demonstrating that the use of the antibody has action in reducing hemolysis and possibly in mitochondrial function of these patients.

Disclosures

No relevant conflicts of interest to declare.
Diagnosing Mds; Do We Really Need to FISH?
Authors: Jamshed Saad , Fricke William , Ogunsesan Yetunde
Published: November 2019

Objectives

Making a definitive diagnosis of myelodysplastic syndrome (MDS) currently entails review of morphology on peripheral blood and bone marrow as well as cytogenetics by standard karyotyping. Fluorescence in situ hybridization (FISH) panel is performed to identify specific abnormalities in addition to karyotyping.

Methods

We reviewed 186 patients who had undergone bone marrow biopsy for suspected MDS from 2016 to 2018 across our health system and subsequently had karyotyping and FISH testing performed.

Results

We identified 186 patients in our study cohort, 164 of these patients had karyotype and FISH testing available. There was excellent concordance rate of 93% (152 of 164) between karyotype and FISH.

Among the 164 bone marrow biopsy samples reviewed, 40(24.4%) eventually had a confirmed diagnosis of MDS. Concordance rate of karyotyping and FISH results in the confirmed cases of MDS was 75% (30 of 40). Overall, 9 of the 40 cases (22.5%) had discordant findings, of these 20% (8 of 40) demonstrated abnormal karyotype analysis with normal FISH while only 1 of 40 (2.5%) had normal karyotype with abnormal FISH diagnostic of MDS. The abnormal FISH finding was a cryptic RUN X1 deletion.

Conclusion

Our study indicated excellent concordance between karyotype and MDS-FISH. FISH rarely added additional value to karyotype.

Disclosures

Jamshed: Takeda Pharmaceutical: Honoraria.
Alterations of Bone Marrow Microenvironment in Acute Graft-Versus-Host Disease
Authors: Lin Yan , Gu Quan , Cheng Hui , Zheng Zhaofeng , Guohuan Sun , Xie Xiaobao , Cheng Tao , Gu Weiying
Published: November 2019

Severe acute graft-versus-host disease (aGVHD) indicates a poor prognosis after allogeneic hematopoietic stem cell transplantation. In our previous study, we found that hematopoiesis was progressively suppressed during aGVHD, while the hematopoietic regenerative potential of donor-derived hematopoietic stem cells remains intact. It prompts us to investigate whether bone marrow niche is a major target of GVHD. We addressed this issue by studying the critical components in bone marrow microenvironment, including mesenchymal stem cell (MSC), osteoblasts and adipocytes in haplo-MHC-matched murine bone marrow transplantation model. By comparing confocal images of femurs from control and aGVHD SCF-GFP mice or Col2.3-GFP mice, we found that both MSCs and osteoblasts were significantly reduced during aGVHD development. In addition, anti-perilipin staining showed that adipocytes were also decreased in aGVHD mice. We found a defect in the differentiation potential of MSCs from aGVHD niche by in vitro culture of both murine and human bone marrow niche cells. qRT-PCR showed decreased gene expressions of PPAR-gamma, Adipoq, Runx1 and Col2a1, suggesting the potential of MSCs differentiation into adipocytes and osteoblasts was blocked. These data provide new insights into the pathogenesis of aGVHD and may improve the clinical management of aGVHD.

Disclosures

No relevant conflicts of interest to declare.
Addiction of B Cell Lymphomas to microRNA-17-92 Is Mediated By a Single Target Gene
Authors: Schoeler Katia , Mittermeier Teresa , Villunger Andreas , Rajewsky Klaus , Labi Verena
Published: November 2019

Mature microRNAs (miRNA) are short non-coding RNAs that regulate gene expression by binding to messenger RNAs (mRNA) in a sequence-specific manner, causing translational repression and/or mRNA decay. The mammalian genome harbors thousands of miRNA genes, many of which are organized into transcriptionally co-regulated clusters such as miR-17-92.

Knockout of the miR-17-92 cluster gene in mice blocked B lymphopoiesis, and ectopic miR-17-92 expression sufficed to initiate B cell lymphomas and autoimmunity. In humans, the miR-17-92 gene is commonly amplified or overexpressed via MYC-driven transcription in diffuse large B cell and Burkitt's lymphomas.

A computationally predicted shared target of the miR-17-92 miRNAs is the pro-apoptotic BCL-2 family protein BIM, central to life-death decisions in mammalian cells. To clarify the contribution of miR-17-92:Bim interactions to the miR-17-92 knockout and overexpression phenotypes, we engineered a unique in vivo system of conditional mutagenesis of the nine Bim 3'UTR miR-17-92 binding sites. Instead of causing the predicted B cell developmental block, interruption of miR-17-92:Bim interactions produced a selective inability of B cells to resist cellular stress; and prevented lymphocyte hyperplasia caused by Bim haploinsufficiency.

Surprisingly, partial genetic disruption of miR-17-92:Bim interactions was sufficient to fully prevent B cell lymphoma formation in two out of three mice using two independent pre-clinical MYC-driven cancer models. This protective effect could be attributed to an increased activity of the mitochondrial apoptosis pathway in pre-malignant B cells, as apoptosis was abolished by concomitant overexpression of an anti-apoptotic BCL-2 protein. MYC-driven B lymphoma cells are addicted to miR-17-92 function. Our data build on these results and strongly suggest that miR-17-92:Bim interactions are vital in this context as acute ablation of miR-17-92:Bim interactions effectively promoted lymphoma cell apoptosis, both in vitro and in vivo.

In conclusion, among hundreds of putative miR-17-92 target mRNAs a single direct binding partner is vital for lymphoma development and maintenance, a discovery whose therapeutic exploitation is of major relevance.

Disclosures

No relevant conflicts of interest to declare.
Dual Targeting of ALDH1 and ALDH3: A Promising Therapeutic Approach in Acute Myeloid Leukemia
Authors: Perez-Alea Mileidys , Colle Julien , Yazir Muhube , Baier Céline , Labiad Yasmine , Arnoux Isabelle , Venton Geoffroy , Guillaume Guillaume , Ceylan Ismail , Costello Regis T.
Published: November 2019

Background. The aldehyde dehydrogenasesfamily(ALDHs) play a major cytoprotective role in cells via detoxification of a wide range of aldehydes. Their functional activity also extends to modulation of cell proliferation, differentiation and survival of cancer cells. Nevertheless, the identity of the specific isoforms contributing to this in acute myeloid leukemia (AML), the underlying mechanisms and the therapeutic value of ALDH inhibitors remain elusive.

Methods. We conducted a meta-analysis to investigate the impact of ALDHs on clinicopathological parameters and survival in AML patients. The expression of ALDHs and their corresponding enzymatic activities were monitored in AML patient-derived cells (n=83) and pharmacologically inhibited with DIMATE, an irreversible suicide inhibitor of ALDH1 and ALDH3. Targeting of ALDH was evaluated both, in vitro and in orthotopic xenograft tumor models and the molecular mechanisms associated were studied in loss-of-function experiments, luciferase reporter assays and combination-index for DIMATE-drug interactions.

Results. We detected gene amplification or mRNA upregulation of ALDH1 and ALDH3 subfamilies in about 45% of AML (n = 200). The expression of these isoenzymes revealed shorter survival times in patients and strong impact on chemotherapy resistance. Lower enzymatic activity of ALDH was noted in AML patients in the favorable cytogenetic risk group. Consistently, the ALDH activity was significantly higher in patients with refractory AML (>5% blasts after first line treatment) compared to non-refractory patients (p<0,005). Simultaneous inhibition of ALDH1 and 3 activates JNK signaling, compromises glutathione homeostasis and induces a redox state imbalance that is amplified by the accumulation of malondialdehyde and 4-hydroxynonenal-protein adducts. This condition ultimately results in severe oxidative damage and cell death. In AML xenografts with high to moderate resistance to cytarabine, combination with DIMATE promoted strong synergistic responses.

Conclusion. These results provide a proof of concept that AML with increased expression of ALDH1 and 3 may benefit from strategies including inhibitors of these isoenzymes, as single agents or in combination with chemotherapy to overcome patient-specific drug resistance. For these patients, who often have poor responses and no alternative therapeutic plan, DIMATE could be a promising option.

Disclosures

Perez-Alea: Advanced Biodesign: Employment, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties: MPA reports patent WO/2017/064247. Guillaume:Advanced Biodesign: Patents & Royalties: GM reports patent WO/2017/064247. Ceylan:Advanced Biodesign: Patents & Royalties: IC reports patent WO/2017/064247.
A Systematic Review and Meta- Analysis of Randomized Controlled Trials on Primary Ambulatory Thromboprophylaxis (PATP) in Patients with Gastrointestinal Cancers Receiving Chemotherapy
Authors: Thein Kyaw Zin , Quick Donald P. , Oo Thein Hlaing
Published: November 2019

Introduction: PATP in solid cancer patients remains uncertain and is not routinely recommended although thrombosis is shown to be the second leading cause of death in cancer patients. Many studies failed to demonstrate in solid cancer outpatients improvement in overall survival despite decreasing venous thromboembolism (VTE) rates by PATP. We conducted a systematic review and meta-analysis of RCTs to determine the benefit and risk of PATP with low-molecular weight heparins (LMWHs) and direct oral anticoagulants (DOACs) in patients with gastrointestinal cancers receiving chemotherapy.

Methods: We performed a comprehensive literature search using MEDLINE and EMBASE databases through June 30, 2019. The references of all potential studies were also reviewed for any additional relevant studies. The RCTs with reduction in VTE as a primary or secondary endpoint and the major bleeding (MB) as a safety outcome were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% confidence interval (CI). Heterogeneity was assessed with Cochran's Q- statistic.

Results: A total of 1,932 patients with gastric, gastroesophageal junctional (GEJ) and colorectal cancers from a subgroup of three RCTs were included in our meta-analysis. The prophylactic doses of LMWHs and DOAC (rivaroxaban) were used in the studies. The duration of LMWH and DOAC ranged from 3 to 6 months. The randomization ratio was 2 to 1 in PROTECHT study and 1 to 1 in all other studies. The I2 statistic for heterogeneity was 0, suggesting homogeneity among RCTs. The VTE incidence was 13 (1.26%) in PATP group and 23 (2.55%) in control group with a RR of 0.49 (95% CI: 0.25 to 0.96, P = 0.04). The absolute RD in VTE was -0.01 (95% CI: -0.03 to -0.00, P 0.04) with an estimate of the number needed to treat (NNT) of 78 to prevent one VTE event. In a subset of patients with gastric and GEJ cancers (n=587), the VTE incidence was 4 (1.37%) in PATP group and 10 (3.40%) in control group with a RR of 0.40 (95% CI: 0.13 to 1.24, P = 0.11).

Conclusions: In our study, the relative risk reduction is 48% with a NNT of 78 to prevent one VTE in ambulatory patients with gastrointestinal cancers. Nevertheless, there is no statistically significant reduction in VTE events in a subset of gastric and GEJ cancers which are considered high risk in Khorana score. Based on the findings, PATP is not recommended in patients with gastrointestinal cancers on chemotherapy at this time. Further studies are necessary to define high risk subsets of gastrointestinal cancer patients receiving chemotherapy who may benefit from PATP.

Disclosures

Oo: Medical Education Speakers Network: Honoraria; Janssen and Janssen: Other: site co-investigator.
Non-Hematologic Therapy Toxicities Correlated with Survival, Drug Discontinuation and Response in Multiple Myeloma Patients: A Retrospective Study
Authors: Huang Weimin , Wei Yongqiang , Zheng Jingxia , Wei Xiaolei , Feng Ru
Published: November 2019

Background

The age distribution character makes Multiple myeloma (MM) a geriatric disease. Several geriatric assessment models have built for the identification of the unfit patients and making individual treatments. However, their prediction value on treatment-related toxicities is limited or lacking. It is time to identify the significance of treatment-related toxicities.

Methods

A total of 119 patients consecutively diagnosed as active MM with previous untreated between 2010 and 2018 in Nanfang Hospital were reviewed.

Results

Among all 119 patients analyzed, 30 patients exhibited grad 3-4 non-hematologic adverse events (non-HAEs). The MM patients with non-HAEs showed more likely to present geriatric features, such as poor physical status (PS) and renal function, lower hemoglobin (HGB) and albumin (Alb), higher N-terminal B-type natriuretic peptide (NT-proBNP) (P<0.01). Patients with non-HAEs presented poor overall survival (OS), higher drugs discontinuation rate and poor overall response rate (ORR) at 4 months (P<0.01). The multivariate analysis showed that non-HAEs is an independent unfavorable factor for OS, drug discontinuation and response at 4 months.

Conclusions

Non-hematologic therapy toxicities are correlated with geriatric features, poor survival, high drug discontinuation rate and poor response at 4 months.

Disclosures

No relevant conflicts of interest to declare.
Plasmablastic Lymphoma - Experience with Infusional EPOCH Chemotherapy from India
Authors: PK Jayachandran , Rajan Arun Kumar , Mehra Nikita , Selvarajan Gangothri , Girishchandra Joshi Archit , Karunakaran Parathan , Dhanushkodi Manikandan , Radhakrishnan Venkatraman , Kannan Krishnarathinam , Ganesan Trivadi S , Sagar Tenali Gnana
Published: November 2019

Background: Plasmablastic lymphoma (PBL) is a rare type of aggressive large B - cell Non Hodgkin Lymphoma (NHL) which was initially described in HIV positive individuals and later was also described in immune competent individuals. It constitutes about 2-3% of HIV associated malignancies. It was included as a distinct entity in WHO lymphoma classification in 2008.

Methods: The clinical features, HIV status, treatment details and outcomes of patients diagnosed with plasmablastic lymphoma during the period of January 2012 to December 2018 were retrospectively collected from the patient records and analyzed. The survival analysis was done by Kaplan Meier analysis and the comparison was done by Log Rank test.

Results: Median age of 25 patients, included in the study was 41 years (Range 13 - 71 years). Males constituted 76% (n=19). HIV positivity was 72% (n=18). Stage 4 disease was present in 76% (n=19). Extra nodal involvement was seen in 96% (n=24), of which the common sites were gastrointestinal tract and bone. Out of 25 patients, 7 did not receive any treatment and 3 received metronomic oral chemotherapy due to poor performance status at presentation. Fifteen patients received chemotherapy on a curative intent. Infusional EPOCH chemotherapy was given in 13 patients. CHOP and CHOPE chemotherapy was given in one patient each. The median number of cycles was 6 (Range: 3 - 8). The overall response rate of patients treated on a curative intent was 80% (Complete response and partial response in 8 and 4 respectively). Three patients underwent high dose chemotherapy with autologous stem cell rescue at first remission (2 HIV patients and 1 Non HIV patient). The median overall survival (OS) of the whole study population was 12.4 months with a median follow of 15.9 months. The Medial OS was not reached in the curative intent group and the 2 year OS of the curative group was 55% with a median follow up of 22.8 months. The factors adversely influencing the OS were Age > 40 years and High IPI (International prognostic index).

Conclusion: Plasmablastic lymphoma commonly presents as stage 4 disease with extra nodal involvement. It is more common in immunodeficient individuals especially HIV positive patients. Infusional EPOCH chemotherapy is a promising option which induces long term remission in fit patients.

Figure

Disclosures

No relevant conflicts of interest to declare.
Lung-Resident Megakaryocytes Display Distinct Transcriptional and Functional Properties
Authors: Yeung Anthony K , Villacorta-Martin Carlos , Hon Stephanie , Dowrey Todd W , Murphy George J
Published: November 2019

Megakaryocytes (MKs) are responsible for producing anucleate platelets which are indispensable due to their roles in hemostasis, growth and development. Recent studies have also demonstrated the influence of platelets in regeneration and immune protection, thus highlighting the functionality of platelets beyond their classically defined roles. Standard models of thrombopoiesis emphasize that MK development occurs initially in the fetal liver during development, followed by long-term residency in sites of adult hematopoiesis such as the bone marrow sinusoids. Outside of the hematopoietic system, MKs have been shown to reside in the interstitium of the lung, with emerging evidence pointing to the lung microvasculature as a specialized environment that may support a significant bulk of platelet production. However, little is known about how MKs traffic to the lung and whether they are influenced by the lung microenvironment to become functionally distinct from their hematopoietic counterparts. To characterize the transcriptional signature of lung-resident MKs, we performed single cell RNA sequencing (scRNA-Seq) on primary MKs derived from syngeneic mouse lung and hematopoietic tissues. Samples were processed to obtain single cell suspensions, followed by flow cytometry to enrich for CD41 positive cells and prepared for scRNA-Seq using the 10x genomics platform. scRNA-Seq analysis revealed a developmental trajectory starting from megakaryocyte erythroid progenitors (MEPs) and ending in two distinct clusters of mature MKs which were made up of mostly lung derived MKs (Fig. 1). One of these mature clusters was made up of 91% lung MKs and possessed a unique gene enrichment profile, including marked upregulation of platelet factor 4 (PF4) and enrichment for cellular processes related to ATP production and translation. To further profile lung-resident MKs, we performed flow cytometric assessment of ploidy and maturation markers. In comparison to bone marrow derived MKs, lung derived MKs displayed a distinct ploidy profile with a significantly increased number of cells expressing CD42, a marker of MK maturation. Collectively, these findings suggest that the subset of MKs found within the lung may be in a more mature and metabolically active state to potentially facilitate increased platelet output. These studies may shed new light on the process of MK maturation, including what triggers MK endoreplication, and may advance methodologies for in-vitro platelet production. Based on the symbiotic relationship between the lung and the hematopoietic system, our ongoing studies are focused upon the interplay between the lung and resident MKs in the developmental and functional patterning of both tissue types.

Disclosures

No relevant conflicts of interest to declare.
Clinical Evidence of Granulocyte-Monocyte Progenitor (GMP) Stem Cell Involvement in Plinabulin's Mechanism of Action (MoA) for the Prevention of Docetaxel (Doc) Chemotherapy (Chemo)-Induced Neutropenia (CIN)
Authors: Blayney Douglas W. , Huang Lan , Mohanlal Ramon
Published: November 2019

Introduction:

Plinabulin (Plin) is being developed as a novel non-Granulocyte colony stimulating factor (G-CSF) for CIN prevention. Previously we reported that Plin was equally effective as Pegfilgrastim for the prevention of grade 4 CIN in a Phase (Ph) 2 trial in NSCLC patients (Pts) receiving 75 mg/m2 Doc (Blayney, ASH 2017, 2018). Plin is single dose per cycle, on the same day of (and 30 min after) Chemo, does not cause bone pain and has anticancer activity. Plin is separately developed as an anti-cancer agent in a global Ph3 trial in NSCLC pts (NCT02504489). Preclinical studies showed that Plin reversed Chemo-induced inhibition of progenitor LSK differentiation in bone marrow (Ghosh, AACR 2018). We have shown that peripheral blood CD34+ hematopoietic stem cell counts increase in chemo plus plin treated patients (Blayney ASH, 2018). Since normal differentiation of GMPs leads to increases in peripheral blood myelo-monocytic (M) and granulocytic cells [neutrophils(N), eosinophils (E) and basophils (B)], we hypothesize that if GMPs are involved in Plin's CIN MoA, increases in N count would positively correlate with increases in M, E and B counts.

Method: The Ph 3 portion of study BPI-2358-105 (NCT03102606) evaluated Plin (40mg) head-to-head with Pegfilgrastim (6mg) for the prevention of Doc-induced CIN in patients (pts) with NSCLC, BC or HRPC. Blood N,M,B and E counts were taken at screening, pre-and post-dose during Cycle 1 and analyzed by a central laboratory (Covance). Pts received dexamethasone (Dex) pre-medication on day (D) 0,1,2, and on D1 Docetaxel (Doc) 75 mg/m2 followed by Plin (40 mg), 30 min after completion of Doc. Here we only include data from a pre-planned interim analysis, and from the Plin arm only (n=52), and we calculated the maximum increase in N,M,E and B on day (D) 5,6,7,8,9,10 15 as % of screening counts, since N,M,E and B counts on D1-D5 are confounded by demargination and Dex effects on these counts.

Results: Pearson correlation coefficients (r) with associated p-values were calculated for maximum increases in N and compared with those for M,E and B, and summarized below.

Conclusions: Correlation of M, E, and B with neutrophil count increase, further confirms our proposed MoA for Plin prevention of CIN: Plin protects the neutrophil precursor from chemotherapy induced damage in bone marrow. We will further explore this MoA in other CIN studies.

Table

Disclosures

Blayney: BeyondSpring Pharmaceuticals: Research Funding. Huang:BeyondSpring Pharmaceuticals: Employment. Mohanlal:BeyondSpring Pharmaceuticals: Employment.
Determination of Appropriate Deferral Time for Repeat Apharesis Platelets Concentrate Donation in Abuja, Nigeria
Authors: Ukoma Chi-Kadibia Theophilus , Ogbe Oche P. , Wakama Tamunomieibi T. , Njoku Ogbonnaya S.
Published: November 2019

Background: Plateletpheresis is the process by which a therapeutic adult dose of platelet concentrate is produced from a single donor using automated cell separator equipment. Recently, the demand for Apheresis Platelets concentrate transfusions has been increasing in our hospitals. This has been attributed to increased cases of malignancy associated bone marrow suppression and various other causes of thrombocytopaenia and thrombopathies. The Increasing use of myeloablative chemotherapy in treatment of haematological and other malignancies also results in transient severe fall in platelet count. The demand generally outstrips the supply necessitating the need to search for additional donor sources to increase the supply of platelets for transfusion. Is it therefore possible to reduce the time interval between plateletpheresis while maintaining donor safety?

Aims and Objectives: The aim of the study was to determine the platelets recovery time after platelets concentrate donation with a view to determining the appropriate deferral time for repeat plateletpheresis

Methods: The study was conducted at the National Hospital Abuja. Fifty seven healthy plateletpheresis donors were recruited over a period of seven months and their haematological parameters were analyzed on days 0, 2 and 7 post donation. We excluded donors whose pre-donation platelet count were less than 200 x 109/L

Results and Analysis: Analysis was done in only forty eight (48) donors as nine (9) participants withdrew before the end of the study. The results show There was a significant decrease in the platelets counts (p <0.001), with subsequent good platelets recovery post donation (Pre: 259.83±44.61 x 109/L; Post - Day 0: 205.29±36.77 x 109/L, day 2: 216.88±32.71 x 109/L and day 7: 240.3±41.83 x 109/L). The apheresis donors recovered 64.29% of the lost platelets by day 2 of donation and subsequently attain 92.49% of pre-donation count within 7 days of donation. There was a statistically significant transient increase in the immediate post donation haemoglobin concentration (14.72±1.32)g/dL but this gradually reduced on day 2 (13.75±1.04)g/dL and 13.83±1.04g/dL on day 7 showing no significant different from the pre-donation Hb of 13.96±1.02g/dL

Conclusion: This study has shown statistically significant platelets recovery 7 days after plateletpheresis making a 7 day deferral for repeat plateletpheresis feasible in our environment. The study also shows feasibility of a 2 days deferral as recommended by AABB. Strict monitoring and pre-donation evaluation of donors should be done to prevent any adverse events such as anaemia and thrombocytopenia.

Disclosures

No relevant conflicts of interest to declare.
Study of Diagnosis, Classification and Prognostic Factors Determination of Acute Leukemia By Flow Cytometry Immunophenotyping
Authors: Silva Alessandra Suelen Jardim , Freire Juliana Mendonça , Júnior Lenilton Silva DA Silva , Oliveira Gustavo Henrique de Medeiros , Silva Antonia Eduarda Martins Oliveira Elói , Lima João Pedro Andrade , Soares Victor lima , Freitas Rodrigo Villar , Bahia Frank , Oliveira Taissa Moura , Silva Dany GKC , Sales Valéria SF , Araujo Rafael Santiago , Paiva Hugo Diogenes De Oliveira , Paiva Aldair Sousa , Cavalcanti Geraldo Barroso
Published: November 2019

Introduction: Acute leukemias (AL) are clonal diseases classified into two large groups: acute lymphoid leukemia (ALL), more common in children, and acute myeloid leukemia (AML), more rare in childhood, besides the rare phenotype leukemias such as acute biphenotypic leukemia (ABL) and undifferentiated acute leukemia (UAL). Although the cytomorphology still be relevant in theses leukemias diagnoses, the immunophenotyping by flow cytometry (FC) have become essential in the diagnosis, classification and follow-up of these neoplasms, standing out as a modern and practical methodology, presenting characteristically as a method of multiparametric and quantitative analysis of the leukemic cells. Objective: The objective of this study was realize a retrospective study of immunophenotyping in 371 patients with AL. Methodology: Immunophenotyping was performed biological samples by FC after labeling with a panel of monoclonal antibodies specific for AL directed against lymphoid antigens (B, T and NK cells), myeloid, and markers related to other cell immaturity. At the same time, information was obtained regarding patients such as age, sex, clinical data related to the disease, and previous hematological analysis. Results: From 371 cases, 127 were ALL (71 B lineage and 55 T=ALL), 239 AML, 04 ABL and 2 UAL. In the ALL, it was observed a higher frequency in children, contrasting with the cases of AML, ABL and UAL more prevalent in adults. In ALL, clinical signs and laboratorial data related to disease were more present in the ALL-T and mature-B corroborating with information in the literature. In AML, ABL and UAL the most clinical parameters observed were splenomegaly, hepatomegaly and bleeding. The classification FAB subtypes of AML more predominant were M1, M2 and M4 and lower incidence of the M7 subtype. Conclusion: These data demonstrate the importance of FC technology in the diagnosis, classification and establishment of prognostic factors of these neoplasms.

Disclosures

No relevant conflicts of interest to declare.
Risk Factors and Trends for Incidence of Acute Coronary Syndrome after Hematopoietic Stem Cell Transplant - a 15-Year Experience with National Inpatient Sample
Authors: Sidhu Jasdeep Singh , Virk Jeevanjot Kaur , Handa Shivani , Mandal Amrendra , Rajeeve Sridevi
Published: November 2019

Background:Significant improvement has been noted in the outcome of patients with advanced hematologic malignancies with the advances in hematopoietic cell transplantation (HCT) techniques. However, it has been observed that patients receiving HCT have increased risk of cardiovascular disease (CVD) over time with increased risk of cardiovascular mortality.

Materials and Methods:This was a retrospective observational analysis. We queried the National Inpatient Sample database from 1998 to 2012 for patients aged ≥18 years who had received HCTin the past and were admitted for non-ST-elevation acute coronary syndrome (NSTE-ACS) or ST-elevation myocardial infarction (STEMI). We performed univariate logistic regression followed by multivariate logistic regression analysis to study various demographic factors and comorbiditiesand temporal trends of ACS in these patients.

Results:A total of 150,072 patients with prior history of HCT were identified, out of which 952 hospitalizations were for ACS.47.16% of these patients underwent Percutaneous CoronaryIntervention.Mean age for ACS patients was 56.98 years and 71.75% patients were male. The demographic factors found to significantly affect the incidence of ACS were increasing Age (OR 1.02, p=0.01) and Insurance(Medicare as reference)[Medicaid(OR 0.3, p=0.04), private(OR 1.66, p=0.01). Charlson Comorbidity Index (CCI) had significant correlation with incidence of ACS (CCI=1 as reference) [CCI=2(OR 0.12, p=0.00), CCI³3(OR 0.60, p=0.01)]. The Medical comorbidities found to significantly affect the outcome were Congestive Heart Failure (OR 1.53, p=0.04), COPD(OR 0.54, p=0.02), smoking(OR 2.96, p=0.00), underlying CAD (OR 39.65, p=0.00) and Pulmonary Hypertension (OR 4.01, p=0.00). A trend analysis for Incidence of ACS in patients with History of HCT showed overall decline in ACS incidence which was found to be statistically significant. (Trend p-Value 0.003).

Conclusion:Our study identifiedvarious factors affecting incidence of ACS in HCT patients. We also discoveredan overall downward trend in incidence of ACSin HCT patients.Further studies need to be conducted to confirm these findings.

Disclosures

Rajeeve: ASH-HONORS Grant: Research Funding.
Residual TP53 Mutation Contributes to Chemoresistance through Clonal Expansion in Acute Myeloid Leukemia
Authors: Yan Bowen , Chen Qinwei , Xu Jianfeng , Li Wei , Xu Bing , Huang Suming , Qiu Yi
Published: November 2019

TP53 mutation (TP53mut) associates with poor survival in AML patients. However, the risk of residual TP53mut has not fully characterized. We found there are around 3% of patients have detectable residual (less than 25%) TP53mut reads from TCGA AML patient exon sequencing data under current sequencing depth. Importantly, these patients also showed worse outcome as compared to the TP53 wild type patients. We therefore studied the effect of residual p53 mutation using two AML cell lines, OCI-AML2 and MV4-11. Both cell lines have been characterized as p53 wild type cells. However, a distinct p53 single hotspot mutation transcripts were detected in low frequency with RNA-seq analysis in both cells. TP53mut cells isolated from the parental cells show higher drug tolerance and have higher population of stem cell maker positive cells, a characteristic of chemoresistant cells. When mixed with p53 wild type cells, the TP53mut cells also show survival advantage under chemo-drug pressure in vitro and vivo (Fig. A), suggesting its advantage to become chemoresistant cells. Interestingly, the chemo-drug resistant cell lines derived from both lines have homogeneous TP53mut at same spot as parental residual mutation cells. Further, we found two p53 target genes p21 and GADD45A contribute to cell survival and chemoresistance. Decrease of these genes leads to cell less sensitive upon chemo-drug treatment. We previously showed that histone deacetylase inhibitor Romidepsin can resensitize chemoresistant cells. Here we further show that Romidepsin can reactivate p53 targeted genes which are failed to be activated by mutant p53 (Fig. B), including p21 and GADD45A, through increasing gene promotor histone acetylation. Moreover, it can preferentially target p53 mutant cell subpopulation (Fig. C). Therefore, either single treatment or combination with chemotherapy drug, Romidepsin can potentially cure or prevent residual p53 mutation caused chemoresistance and relapse in patient. Taking together, our study raise importance on previous under looked residual p53 mutation in AML patient and shed lights on therapeutic strategies for treatments on chemoresistance.

Figure

Disclosures

No relevant conflicts of interest to declare.
BRAFV600E-Positive Precursors As Molecular Markers of Bone Marrow Involvement in Pediatric Langerhans Cell Histiocytosis
Authors: Kudo Ko , Kanezaki Rika , Kobayashi Akie , Sato Tomohiko , Kamio Takuya , Sasaki Shinya , Masaru Imamura , Imai Chihaya , Irie Masahiro , Sasahara Yoji , Ando Kumiko , Kakuda Harumi , Doi Takehiko , Kawaguchi Hiroshi , Kudo Kazuko , Kanegane Hirokazu , Terui Kiminori , Toki Tsutomu , Ito Etsuro
Published: November 2019

Introduction: The BRAF mutation V600E, the most common somatic mutation in Langerhans cell histiocytosis (LCH), has been reported in approximately 50% of LCH patients and is associated with certain high-risk clinical features. Precursors harboring this mutation can differentiate into Langerhans cells resulting in infiltrates in multiple organs under inflammatory conditions. However, BRAF status in the bone marrow of pediatric LCH patients is unclear. The present study examined somatic mutations in paired tumor and bone marrow samples, using a highly sensitive assay involving next-generation targeted sequencing and droplet digital polymerase chain reaction (PCR) for pediatric LCH patients.

Methods: Between 1996 and 2019, in total of 17 Japanese pediatric patients with LCH were enrolled. The male/female ratio was 7/11. Ages of onset of LCH were median 13 months (range 5-193 months). At diagnosis of LCH, 2 patients were positive for risk organ involvement, 15 were negative. We retrospectively performed mutational analyses of 17 LCH cases using formalin-fixed paraffin-embedded LCH tumor specimens to provide templates for PCR-based targeted amplicon sequencing with customized primers to detect mutations in exons 12 and 15 in BRAF, and exons 2 and 3 in MAP2K1. Thereafter, we identified somatic mutations in the 17 paired bone marrow samples via droplet digital allele-specific PCR, targeting BRAF V600E and BRAF exon 12 in-frame deletion 496-500 (Ex12 in-del).

Results: We detected BRAF V600E in 11 of 17 tumor samples (65%) and the BRAF Ex 12 in-del in 3 of 17 tumors (18%). We identified BRAF V600E in bone marrow samples in 10 of the 11 cases (90%) with the mutation in the tumor at low variant allele frequency (median 0.25%, range 0.14-7.0%). BRAF Ex 12 in-del was not detected in the bone marrow. Cases with detectable bone marrow involvement included eight patients with multi-system disease affecting multiple organs, one patient with multi-focal bone disease, and one patient with single-system disease. Clinical phenotypes including relapse did not correlate with BRAF V600E upon detection in the bone marrow.

Conclusion: We established the sensitive assay based on PCR-based targeted NGS for detecting somatic mutations in LCH even accessible for formalin-fixed, paraffin-embedded clinical specimens. Bone marrow involvement is frequently detectable at the molecular level in pediatric LCH with the BRAF V600E mutation. A prospective study is warranted to evaluate the clinical impact of mutational burden in bone marrow.

Disclosures

Kudo: Unum Therapeutics: Patents & Royalties. Imai:Juno Therapeutics: Patents & Royalties.
HOXA11 Regulates Chemoresistance By Modulating p53 Gene Expression in Acute Myeloid Leukemia
Authors: Guo Xutao , Yan Bowen , Qiu Yi
Published: November 2019

Acute myeloid leukemia (AML) exhibits large intrinsic variation in drug responsiveness due to its inherent heterogeneity. Therefore, it is important to understand the resistant mechanism in order to improve the treatment. In our previously study, the OCI-AML2-resistant cell lines were established to resist cytarabine (Ara-C) in the concentration of 50 µM (OCI-AML2 R50). The RNA-seq results showed that many genes changed in the resistant cells compared to wild type OCI-AML2 cells. One of the most remarkably decreased gene in resistant cells was HOXA11 (Homeobox A11). It is the part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which regulates gene expression, morphogenesis, and differentiation. In this study, we have evaluated the importance of HOXA11 in AML chemoresistance. We found that knockdown of HOXA11 repressed the WT OCI-AML2 cell proliferation and increased the population of cells expressing CD123 and CD47 LSC (Leukemia stem cell) markers and enhanced the resistance to Ara-C in vitro, while overexpression of HOXA11 showed the reverse effect. These results support the idea that HOXA11 promotes drug sensitivity and apoptosis in AML. However, the result also showed that overexpression of HOXA11 repressed the OCI-AML2 R50 cell proliferation and enhanced the resistance. Therefore, HOXA11 plays opposite role in sensitive cells and resistant cells. We further investigated the mechanism for these effects. We found that knockdown of HOXA11 decreased the p53 gene expression and overexpression of HOXA11 increased the expression of p53 in OCI-AML2 and R50 cells. Further, in OCI-AML2 R50 cells p53 has a hotspot mutation in DNA binding site and studies have shown that p53 mutation enhance cancer cell survival and chemoresistance. Therefore, our study shows dual roles for HOXA11 in cell survival. In p53 wild type parental AML2 cells, HOXA11 induces wild type p53 expression to enhance drug sensitivity while in resistant cell, HOXA11 promotes mutant p53 expression and enhances the resistance of chemotherapy.

Disclosures

No relevant conflicts of interest to declare.