bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacokinetics-Guided Perioperative Replacement Therapy in Hemophilia a Patients
Authors: Meng Lei , Lv Jiaxin , Chen Bin , Li Qiang , Liu Zhuqin , Jiang Guiyong , Xun Yufang , Liu Fei , Chen Keyu , Liu Qifa , Sun Jing
Published: November 2021

Purpose: Pharmacokinetics(PK)-based prophylactic treatment has been proven to meet the pharmacoeconomics needs of patients with hemophilia to the greatest extent in recent years，but the way and significance of PK-guided perioperative replacement therapy remain unclear.

Methods :In this study, PK parameters (calculated by DAS software), including half-life and in vivo recovery(IVR), were used to guide individualized replacement therapy for surgical patients with hemophilia A. PK profiles were described by a two-compartment model. The collection of perioperative factor VIII(FVIII) plasma concentrations, factor consumption, and blood loss data was used to verify the efficacy of individualized programs.

Results :A total of 46 patients underwent 50 surgeries (median age: 32 years, median weight: 60.5 kg), all of which were major surgeries. The median half-life was 15.44h, and the median IVR was 2.29IU dl -1/IU kg -1. In total, 50 surgeries contributed with 528 plasma FVIII activity observations, of which 310 (58.71%) entered the target range. The median intraoperative blood loss of 43 surgeries was 446.9ml. No severe complications occurred during the perioperative period. Hematomas appeared after six surgeries, which have been resolved after treatment at discharge. Inhibitor developed in one patient and was transient. The median consumption of FⅧ concentrates during the perioperative period was 511.7U/kg, which reduced by 26.69% compared with the dosage based on weight (648.3U/kg, P＜0.001). During the perioperative period, the actual factor consumption was consistent with the PK-guided plan (P>0.05). In addition, a negative correlation was found between intraoperative blood loss and immediate postoperative FVIII activity (r= -0.477, P=0.001).

Conclusion: PK-guided perioperative replacement therapy in hemophilia A patients can safely and effectively reduce the consumption of FⅧ concentrates.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
S1P/S1PR1 Signalis Required for Optimal T-Cell Pathogenicity to Induce Gvhd By RegulatingDrp1/mTOR Axis
Authors: Tian Linlu , Wu Yongxia , Choi Hee-Jin , Sui Xiaohui , Sofi Mohammed Hanief , Kassir Mohamed Faisal , Martin Paul J , Mehrotra Shikhar , Ogretmen Besim , Yu Xue-Zhong
Published: November 2021

Allogeneic hematopoietic cell transplantation (allo-HCT) is a curative option for the treatment of hematological malignancies, which is primarily mediated by donor immune cells. Acute graft-versus-host disease (aGVHD) mainly induced by transplanted donor T cells is a major and life-threating complication leading to severe "cytokines storm" and multiple organ damage, which contributes to high morbidity and mortality and thus limits the success of allo-HCT. Sphingosine-1-phosphate (S1P), a bioactive lysophospholipid, is synthesized from sphingosine by sphingosine kinase 1 (Sphk1) or Sphk2 and degraded by S1P lyase. S1P signal plays an important role in regulating biological functions and homeostasis of T lymphocytes, and thus has been considered as a therapeutic candidate against autoimmune disease. In current study, we demonstrated that Sphk1 but not Sphk2 is required for antigen-presenting cells (APC) to activate allogeneic T cells. Using murine allo-HCT models, we found that secretory S1P produced by Sphk1 in the recipients was required for the development of full-blown GVHD (Fig. 1 A-B). Consistently, S1PR1, a primary receptor for S1P, plays a critical role in the pathogenicity of donor T cells to induce GVHD (Fig. 1C). Using pharmacologic inhibitors, we demonstrated that specific inhibition of Sphk1 (PF543) or S1PR1 (W146) substantially attenuated GVHD while preserving graft-vs.-leukemia (GVL) effect (Fig. 1D). Mechanistically, S1P/S1PR1 signal facilitated T-cell activation and differentiation towards Th1/Th17 but away from Tregs (Fig. 1E) and also promoted T-cell migratory potential into GVHD target organs (Fig. 1F). S1P/S1PR1 signaling increased mitochondrial fission of pathogenic CD4 + T cells through PRKAA1 dependent Drp1 and phosphorylated S6 (pS6) activation (Fig. 1 G-H). Whereas CD8 + T cells were much less sensitive to S1P-S1PR1-PRKAA1-pS6/Drp1 axis, which likely contributed to the GVL maintenance when S1P/S1PR1 signaling is absent or inhibited (Fig. 1 D, G). Furthermore, clinical data demonstrated that patients with acute GVHD exhibited a comparable level of sphingosine but a significantly higher level of S1P, as compared to the patients without GVHD, suggesting a positive role of S1P in GVHD development in clinic (Fig. 1I). Finally, we validated the efficacy of inhibiting Sphk1/S1PR1 in GVHD prevention induced by human T cells in a xenograft model (Fig. 1J). Taken together, our results provide a rationale and novel mechanism of targeting Sphk1/S1PR1 in the prevention of GVHD and leukemia relapse after allo-HCT. This novel strategy may be translated in the clinic to benefit patients with hematologic malignancies.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
Resveratrol As a Novel Treatment for Recurrent Epistaxis in SMAD4+ Hereditary Hemorrhagic Telangiectasia
Authors: Gill Shahbegh , Swaidani Shadi , Parambil Joseph , McCrae Keith R.
Published: November 2021

Introduction

Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal dominant disorder characterized by the development of arteriovenous malformations or telangiectasias that may affect any organ system, but are most prevalent in the nose and gastrointestinal tract. Nasal telangiectasia account for epistaxis, the most frequent manifestation of HHT, which may be frequent, debilitating and lead to decreased quality of life. Epistaxis is quantified by the Epistaxis Severity Scores (ESS), which ranges from 1-10 with higher scores associated with more severe bleeding. The diagnosis of HHT is based on clinical criteria and requires three or more of the following features: epistaxis, mucocutaneous telangiectasis, visceral AVMs, and/or a family history of HHT. HHT is associated with several mutations that may involve ENG, ACVRL1, or SMAD4; the latter occurs in only ~2% of HHT patients, which is also associated with the Juvenile Polyposis Syndrome (JPS), another autosomal dominant disorder associated with an increased risk for colorectal, stomach, small intestine, and pancreatic cancers.

Methods

Case report with serial ESS scores, hemoglobin and hematocrit monitoring.

Results

A 25-year-old male was diagnosed with JPS/HHT and a c.1081C>T mutation in SMAD4 leading to an R361C missense mutation was diagnosed in 2013. The patient had a longstanding history of frequent epistaxis leading to severe iron deficiency anemia and requiring at least two 750 mg iron infusions annually (total of 14), and did not improve with oral iron supplements. In December 2020, the patient initiated a 1 g daily dose of resveratrol for general anti-aging and health benefits. His epistaxis improved immediately, and his ESS decreased from 6 (consistent with severe bleeding) to 1 (no bleeding) over a two week period. The frequency, severity and duration of epistaxis all improved dramatically (Figure). No additional iron therapy has been required since initiation of resveratrol. Recent serum iron and ferritin values (6/2021) were both within normal limits.

Of interest, in parallel with the resolution of epistaxis, the patient also had a dramatic reduction in colonic polyposis after starting resveratrol.

Conclusions

There are no approved therapies for the treatment of HHT, and patients with this disorder may suffer from a markedly reduced quality of life due to unpredictable epistaxis and other manifestations. While a responses to bevacizumab have been reported in 60-70% of patients, treatment is expensive and may be associated with thromboembolic events, and patients may become refractory over time. Invasive approaches such as sclerotherapy may be initially, but only temporarily effective. Thus, there is an urgent need for better HHT therapies.

Figure 1 Figure 1.

Disclosures

McCrae: Sanofi, Novartis, Alexion, and Johnson & Johnson: Consultancy, Honoraria; Dova, Novartis, Rigel, and Sanofi Genzyme: Consultancy.
Haploidentical Stem Cell Transplantation Can be Fully Conducted on an Outpatient Basis
Authors: Murrieta-Álvarez Iván , Olivares-Gazca Juan Carlos , Cantero-Fortiz Yahveth , León-Peña Andrés A. , Priesca-Marin José Manuel , Ruiz-Delgado Guillermo J. , Ruiz-Argüelles Guillermo J.
Published: November 2021

Introduction

Haploidentical hematopoietic stem cell transplantation (haplo-SCT) has become an acceptable approach for many patients; however, the suitability of this procedure and outcomes regarding efficacy and safety remain unclear. Here we present a single-center experience using a conditioning regimen based on cyclophosphamide and fludarabine under outpatient conditions.

Methods:

Retrospective study evaluating the performance of haplo-SCT in a single center. The conditioning regimen was fludarabine 50 mg on days -6 through -4, cyclophosphamide (Cy) 500 mg/m 2 on days -7 to -4 and tacrolimus 1000 mg and post-transplant Cy (50 mg/kg) on days +3 and +4 (Figure 1). Donor cell collection was accomplished through apheresis in all patients and fresh cells were administered on same day of collection. All the procedures were started on an outpatient basis. Overall survival was defined as mortality for any reason, starting to count from the day of transplantation to the date of death. The survival function was calculated according to the Kaplan-Meier estimation method. All patients signed a consent to participate after a thorough interview and the study protocol was approved by Clínica Ruiz IRB.

Results:

We grafted 20 patients, (14 adults and 6 children) with haploidentical cells and found that in 11 cases (55%), the full procedure could be completed totally as outpatients; the diagnosis of the grafted patients were: 10 acute lymphoblastic leukemia, 3 acute myelogenous leukemia, 3 paroxysmal nocturnal hemoglobinuria, and one each non-Hodgkin´s lymphoma, Blackfan-Diamond syndrome and multiple myeloma. Nine patients (3 children and 6 adults) were admitted to the hospital after completing the conditioning, 1 to 8 days after day 0: the causes for admission were neutropenic fever (5 cases), cytokine-release syndrome (3 cases), and intraabdominal abscess (1 case). Patients remained in the hospital for a median of 9 days. Four patients failed to engraft and recovered endogenous hematopoiesis and acute graft versus host-disease developed in 5 of 16 engrafted patients; two patients relapsed after the haplo-SCT. The transplant-related mortality was 35%, whereas the 2-year overall survival (OS) was 37.5% (Figure 2); the causes of the 7 deaths were: Four granulocytopenic sepsis, 2 graft-versus-host disease and one multiple organ failure.

Conclusions

Haplo-SCT procedures can be conducted safely and effectively on an outpatient basis; however, questions remain regarding the selection of patients and managing of complications, especially in outpatient conditions in which full and timely availability of specialized care could be the pivotal factor to improve short-term outcomes.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
Disparity Analysis and Prognostic Value of Pretreatment Whole Blood Epstein-Barr Virus DNA Load and EBER Status in Lymphomas: A Retrospective Multicenter Study in Huaihai Lymphoma Working Group
Authors: Shen Ziyuan , Hu Lingling , Qiao Jianlin , Xu Linyan , Xu Kailin , Zhang Hao , Sang Wei
Published: November 2021

Elevated Epstein-Barr virus (EBV) DNA load is common in lymphomas. However, it remains unclear whether the disparity in viral load and its prognostic value in lymphomas are correlated with EBER status. In this retrospective multicenter study, we collected the data of pretreatment whole blood EBV DNA (pre-EBV DNA) and EBER status and evaluated their disparity and prognostic values in lymphomas. A total of 454 lymphoma patients from December 2014 to August 2020 were retrospectively retrieved. Mann-Whitney U test, Kruskal-Wallis test, and Bonferroni's adjustment were used to explore the disparity of EBV DNA and EBER status in lymphomas. Time-dependent receiver operating characteristic analysis and MaxStat analysis were used to determine optimal cut-off points of pre-EBV DNA load. Univariable and multivariable Cox proportional hazards models were established for the estimation of prognostic factors. The positive rate of EBV-DNA in NKTL patients was higher than that in DLBCL, FL, and HL patients, and the median positive pre-EBV copy number of NKTL was also higher than that of FL and DLBCL. EBV-DNA could clearly distinguish the prognosis of DLBCL, NKTL, HL and PTCL, and the integration of EBER status and EBV DNA could differentiate the prognosis of HL patients. Multivariable results revealed that pre-EBV DNA load had an effect on the prognosis of NKTL, FL and DLBCL. The status of pre-EBV DNA and EBER were disparate. Whole blood pre-EBV DNA predicted the prognosis of lymphomas, and the integration of EBV and EBER status could differentiate the prognosis of HL

Disclosures

No relevant conflicts of interest to declare.
Correlation Analysis of DNA Methylation Level and Clinical Characteristics in JMML Patients
Authors: Cai Yuli , Zhang Jingliao , Yi Meihui , Liu Xiaoming , Zhang Xiaoyan , Wan Yang , Chang Lixian , Zhang Li , Chen Xiaojuan , Guo Ye , Zou Yao , Chen Yumei , Zhang Yingchi , Yang Wenyu , Zhu Xiaofan
Published: November 2021

Objective: As a rare, aggressive pediatric myeloproliferative disease, juvenile myelomonocytic leukemia (JMML) encompassed both biological features of myelodysplastic syndrome and myeloproliferative neoplasm. Studies have shown that the methylation level in JMML patients is closely related to prognosis, and patients with high methylation level have poor prognosis. This study aimed to find clinical indicators that were associated with different methylation levels and prognosis.

Methods: The clinical information of 24 JMML patients with DNA samples admitted to our center from December 2013 to May 2020 was retrospectively analyzed, and the DNA methylation level of their whole genome was detected.

Results: The median age of onset was 14.5 months (0.1-153 months) among the 24 cases, including 17 males and 7 females. At diagnosis, the median WBC count was 27.1×10 9/L (6.2-98.1×10 9/L), and the median platelet count was 38×10 9/L (10-277×10 9/L). Chromosome karyotype abnormalities were found in 12.5% (3/24) of patients. Next-generation sequencing results showed that 79.2% (19/24) patients had at least one Ras pathway-related classical gene mutation, and 41.7% (10/24) patients had two or more somatic mutations. Genomic DNA methylation levels were divided into three groups: 10 cases in the hypomethylation group, 4 cases in the moderate methylation group, and 10 cases in the hypermethylation group. There were significant differences in age, platelets, PTPN11 gene mutation and the number of somatic mutations ≥2 in different methylation groups (P<0.05). The age of hypomethylated group was significantly lower than that of hypermethylated group (P<0.05), and the platelets of hypomethylated group was significantly higher than that of hypermethylated group (P<0.05). Patients ≤12m and platelets＞32×10 9/L had lower DNA methylation level (P<0.0001). The number of patients with PTPN11 gene mutation in the hypomethylated group was significantly lower than that in the hypermethylated group (P<0.05), and the number of patients with ≥2 mutations in the low and medium methylated groups was significantly lower than that in the hypermethylated group (P<0.05). Correlation analysis showed that hypermethylation level was significantly correlated with PTPN11 gene mutation and ≥2 somatic mutations (P<0.001).

Conclusions: JMML patients with high methylation level in the DNA genome at diagnosis were older and with lower platelet levels, and hypermethylation were significantly correlated with high-risk prognostic factors such as PTPN11 gene mutation and ≥2 somatic mutations.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.

OffLabel Disclosure:

Decitabine for treatment of children with JMML
Concordance Study of CD30 Expression Detected By Multiple Immunohistochemistry Assays and Ventana CD30 Assay in Chinese Lymphoma Patients
Authors: Jiang Xiang-Nan , Shi Yang , Li Xiao-Qiu
Published: November 2021

Background: CD30 is emerging as an important biomarker guiding the clinical diagnosis, treatment, and evaluating the efficacy and prognosis of lymphoma. However, there is no standard procedure for specification and interpretation of the pathological detection of CD30 in China. This study intends to evaluate the staining and interpretation concordance of CD30 expression detected by the VENTANA CD30 assay and other multiple immunohistochemistry (IHC) assay in Chinese malignant lymphoma patients.

Design: This is a multi-center, observational study enrolling 1,000 adult patients with a diagnosis of histologically confirmed malignant lymphoma in China. Patients, aged 18 years or older at diagnosis and who provided available formalin-fixed paraffin-embedded (FFPE) samples stored within 2 years, with diagnosis of classical Hodgkin's lymphoma, anaplastic large-cell lymphoma, large cell transformation of mycosis fungoides, diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, extranodal NK/T-cell lymphoma, peripheral T cell lymphoma not otherwise specified, angioimmunoblastic T-cell lymphoma, and pcCD30+ T-cell lymphoproliferative disease were eligible to participate. Exclusion criteria included sample insufficiency for CD30 testing, incomplete sample information, lack of written informed consent.

Methods: Each eligible patient provides an available r FFPE sample. Tissue slides obtained from each eligible FFPE sample will be stained by the VENTANA CD30 assay and at least one of the following IHC assays [umAB256 (zhongshanjinqiao) + Ventana BenchMark; Ber-H2 (Maixin) + Ventana BenchMark；Ber-H2 (Maixin) + DAKO; Ber-H2 (DAKO) + DAKO; Ber-H2 (DAKO) + Ventana BenchMark;umAB256 (Zhongshanjinqiao) + Leica; JCM182 (Leica) + Ventana BenchMark;JCM182 (Leica) + Leica; Ber-H2 (DAKO) + Leica]. CD30 expression of all immunostained slides will be independently interpreted as a percentage of CD30 positive cells by trained pathologists. The primary endpoint will be the staining concordance of percentages of positive cells for CD30 expression detected by each of the nine IHC assays and VENTANA CD30 assay (interpreted by expert panel) Secondary endpoints will be the interpretation concordance of pathologists at sites and the expert panel by assessing CD30 expression detected by various IHC assays. Both primary and secondary endpoint will be evaluated by intraclass correlation coefficient ICC, Bland-Altman, and Pearson correlation method.

Discussion: This planned study will explore more equivalent testing methods to detect the expression of CD30 in Chinese patients with lymphoma.

Disclosures

Shi: Takeda Pharmaceuticals: Current Employment. Li: Takeda Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Other: Receiving lecture fees.
Autosomal Recessive Congenital Dyserythropoietic Anemia Type III Is Caused By Mutations in the Centralspindlin RACGAP1 Component
Authors: Romero-Cortadellas Lídia , Hernández Gonzalo , Ferrer-Cortès Xènia , Venturi Veronica , Olivella Mireia , Pérez de Soto Concepción , Morales-Camacho Rosario M. , Villegas Ana , Gonzalez-Fernandez F. Ataulfo , Morado Marta , Pérez-Montero Santiago , Tornador Cristian , Sánchez Mayka
Published: November 2021

An autosomal dominant form of congenital dyserythropoietic anemia type III (CDA III) is caused by a missense mutation in the KIF23 gene whose protein product, mitotic kinesin-like protein (MKLP1), is part of the centralspindlin complex involved in cytokinesis. Several case reports suggested the existence of an autosomal recessive inheritance form of CDA III so far not genetically characterized. By means of whole exome sequencing in a Spanish CDA III family with healthy parents, we identified in the male proband a novel homozygous missense mutation p.Pro432Ser in the RACGAP1 gene, which encodes for the RACGAP1 protein (Rac GTPase-activating protein 1, also known as MgcRacGAP or CYK-4), the partner of MKLP1 in the centralspindlin complex. A second CDA III Spanish patient has a different rare and novel homozygous missense mutation, p.Thr220Ala, in the RACGAP1 gene. Both patients presented with macrocytic anemia, aberrant multinucleated erythroblasts in the bone marrow typically seen in CDA III cases, no iron overload and skull defects secondary to severe anemia. Silencing of RACGAP1 using siRNA in HeLa cells mimics the cytokinesis defect observed in the bone marrow of our patients. Both mutations disrupt normal cytokinesis and alter the GTPase balance in patients' cells. We conclude that the autosomal recessive form of CDA type III is caused by mutations in the RACGAP1 gene, encoding for RACGAP1 protein, which is the partner of MKLP1 in the centralspindlin complex critical for cytokinesis and now both proteins are associated with CDA type III.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
Systematic Construction of an Autophagic Risk Model in Bone Marrow for Prognostic Prediction in Multiple Myeloma
Authors: Shu Lingling , Huang Han-Ying , Liu Yang , Li Yang , Wang Weida , Li Jinyuan , Chen Shuzhao , Wu Xiaoping , Wang Yun , Lin Huan-xin , Liang Yang
Published: November 2021

Autophagy is an intracellular self-degradative process that balances cell energy source and regulates tissue homeostasis, which plays critical role in the pathogenesis of multiple myeloma (MM). However, the prognostic role of autophagy-related genes (ARGs) in MM remains undefined.

In the present study, the ARGs were obtained from Gene Expression Omnibus datasets (accession GSE24080, GSE136337, GSE57317), which contains 1038 samples of patients with MM. Univariate Cox regression analysis identified 38 ARGs that were significantly associated with overall survival of MM. Furthermore, a risk score model with 11 prognosis-associated ARGs was developed using multivariate Cox regression analysis, including ARNT, ATG4D, BIRC5, BNIP3L, CDKN1A, EIF2S1, IRGM, ITGA3, NCKAP1, NRG1 and TM9SF1. The 3-year area under the curve (AUC) values for the receiver operating characteristic curves were 0.717(0.662, 0.758), 0.646(0.587, 0.703) and 0.906(0.694, 1.000) for GSE24080, GSE136337, GSE57317 prognosis predictions, respectively (Figure A-C). Using this prognostic signature, patients with MM could be separated into high- and low-risk groups with distinct clinical outcomes (Figure D-F). Moreover, autophagy risk score was an independent prognostic factor by multivariate analysis. KEGG revealed that most pathways were related to autophagy and metabolism. Furthermore, we validated the expression of 11 genes and ARNT in bone marrow of MM patients (Figure G-I) and showed the critical role of ARNT-mediated autophagy in the proliferation and drug resistance of bortezomib in myeloma cells (Figure J-M).

In conclusion, we constructed ARGs-based prognostic model to predict the prognosis of MM, targeting specific autophagic gene such as ARNT might provide therapeutic clues for MM treatment.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
Posttransplant Cyclophosphamide-Based Haploidentical Vs Matched Unrelated Donor Peripheral Blood Hematopoietic Stem Cell Transplantation Using Myeloablative Targeted Busulfan-Based Conditioning for Pediatric Acute Leukemia
Authors: Hong Kyung Taek , Park Hyun Jin , Kim Bo Kyung , An Hong Yul , Choi Jung Yoon , Kang Hyoung Jin
Published: November 2021

Haploidentical related donor (HRD) is a common alternative donor strategy used when matched sibling or unrelated donors are not available for hematopoietic stem cell transplantation (HSCT). Post-transplant cyclophosphamide-based graft-versus-host disease prophylaxis is an attractive option when performing a HRD HSCT because of its promising outcomes and easy application. However, there have been no studies comparing HRD HSCT with PTCy and MUD HSCT with antithymocyte globulin, using similar busulfan-based myeloablative conditioning regimen in pediatric acute leukemia. Herein, we compared the outcomes in children and adolescents with acute leukemia after HRD HSCT with PTCy (n=35) and matched unrelated donor (MUD) HSCT (n=45) after targeted busulfan-based myeloablative conditioning using intensive pharmacokinetic monitoring. The median follow-up times of the HRD and MUD groups were 3.7 and 4.6 years. No engraftment failure was observed. The cumulative incidence of GVHD grades II-IV (34.3% versus 48.9%, p=0.142), grades III-IV (2.9% vs. 8.9%, p=0.272), extensive chronic GVHD (11.4% vs. 18.3%, p=0.417), relapse (25.6% vs. 28.0%, p=0.832), and non-relapse mortality (0% vs. 2.2%, p=0.420) were not significantly different. The 3-year severe chronic GVHD-free/relapse-free, leukemia-free and overall survival rates in the HRD and MUD groups were 62.9±8.7% versus 49.8±7.6% (p=0.318), 74.4±8.0% versus 67.5±7.2% (p=0.585), and 88.6±5.4% versus 83.7±5.7% (p=0.968), respectively. In subgroup analyses of patients with acute lymphoblastic leukemia and acute myeloid leukemia, there were no significant differences in outcomes between the groups. Our results demonstrated that HRD HSCT with PTCy using a targeted busulfan-based myeloablative conditioning shows outcomes similar to those of MUD HSCT. HRD HSCT with PTCy could be considered for pediatric acute leukemia patients who lack an HLA-matched donor.

Disclosures

Kang: Cartexell: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis Korea: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen Korea: Membership on an entity's Board of Directors or advisory committees, Research Funding.
Measuring H3K27me3 Reduction after in-Vivo Administration of Ftx-6058; A Potent Polycomb Repressive Complex 2 (PRC2) Inhibitor
Authors: Roth Mark , Xie Keqiang
Published: November 2021

FTX-6058 is an investigational drug for the treatment of Sickle Cell Disease (SCD). The molecule is a selective and potent binder of the embryonic ectoderm development protein (EED). Binding of FTX-6058 to EED inhibits PRC2, a histone methyltransferase which primarily methylates lysine 27 of histone H3. Inhibition of PRC2 results in the reduction of trimethylation at lysine 27 on histone H3 (H3K27me3). Because the level of trimethylation on lysine 27 is the immediate downstream consequence of PRC2 activity, we developed a flow cytometric assay to measure the relative level of H3K27me3 from in-vivo tissue samples. The flow cytometric assay measures the median fluorescence intensities (MFI) of H3K27me3 and total histone H3. The target engagement (TE) measurement is a ratio of H3K27me3 MFI to total Histone H3 MFI. The target cells for FTX-6058 in SCD treatment are the hematopoietic cells of the bone marrow. We demonstrate an FTX-6058 dose dependent decrease in the TE ratio of bone marrow, hematopoietic cells. Translating the TE assay from mouse pre-clinical studies to human clinical trials required use of a less invasive tissue type than bone marrow. In mice, a positive relationship between the TE ratio of hematopoietic, bone marrow cells and circulating monocytes was established. Therefore, a human monocyte TE assay for FTX-6058 was validated for human trials. Research use only (RUO) validation was completed by Q2 Solutions Laboratories. The monocyte FTX-6058 TE assay is currently being evaluated as an exploratory biomarker in Fulcrum Therapeutics' phase 1 clinical trial FIS 002-2020.

Disclosures

Roth: Fulcrum Therapeutics, Inc.: Current Employment, Current equity holder in publicly-traded company. Xie: Fulcrum Therapeutics, Inc.: Current equity holder in publicly-traded company, Ended employment in the past 24 months.
Utilizing HealthTree ® Cure Hub's Real-World Data to Assess Treatment Management of Patients with Multiple Myeloma during the COVID-19 Pandemic
Authors: Sweeney Nathan W. , Ahlstrom Jennifer M.
Published: November 2021

Background: Patients with multiple myeloma (MM) are uniquely susceptible to viral and bacterial illnesses, including COVID-19, due to their immunocompromised state, age, treatments, and comorbidities. With the advent of COVID-19, changes to treatment were recommended whenever possible, in order to reduce visits to the clinic. The total effect of these changes on cancer patients with multiple myeloma remains unclear. The aim of this project was to assess treatment management by changes to treatment of patients with MM during the COVID-19 pandemic.

Methods: We utilized HealthTree ® Cure Hub for Multiple Myeloma (healthree.org) and invited patients with active MM cancer or precursor conditions to participate in an online survey. We analyzed patient responses to questions regarding their myeloma treatments during the COVID-19 pandemic.

Results: 978 MM patients participated in the survey between February to June 2021. Since March 2020, 151 patients (15%) either delayed, postponed, or stopped a myeloma treatment because of COVID-19. The four most common treatments were daratumumab (20%), lenalidomide (15%), stem cell transplant (13%) and zoledronic acid (11%). There were 110 patients that canceled a planned myeloma treatment. Of these patients, 55 (50%) canceled a planned chemotherapy, 15 (14%) canceled a stem cell transplant, 1 (1%) canceled radiation and 39 (35%) indicated other. Eight patients replaced an intravenous or subcutaneous treatment with an oral treatment because of COVID-19. There were 9 patients that started a new myeloma treatment because of COVID-19, the most common being daratumumab (44%), ixazomib (22%), lenalidomide (22%) and carfilzomib (11%). Finally, 15 patients had their lenalidomide (50%), steroid (42%) and carfilzomib (8%) dose changed.

Conclusions: Our results show that decision-making regarding treatment changes were made on an individual basis and that patients who required a change in treatment were the minority. Aggregating real-world data can provide evidence that despite the changes, patients with MM still received and efficacious treatment and avoided putting these patients at risk or mortality.

Disclosures

Ahlstrom: Bristol Myers Squibb: Other: Patient Advisory; Janssen: Other: Patient Advisory; Pfizer: Other: Patient Advisory; Takeda: Other: Patient Advisory.
Meta-Analysis of Chemotherapy-Induced (Febrile) Neutropenia and Chemotherapy Disruptions Associated with Same-Day Versus Standard (24-72h) Pegfilgrastim Administration in Non-Hodgkin Lymphoma Patients
Authors: Alrawashdh Neda , McBride Ali , Abraham Ivo
Published: November 2021

Background: While the product label and international guidelines recommend pegfilgrastim administration 24-72 hours following completion of chemotherapy, increasingly clinicians administer pegfilgrastim using a same-day protocol. We performed a meta-analysis to compare the incidence of febrile neutropenia (FN), chemotherapy-induced neutropenia (CIN) grade 4, and CIN/FN-related chemotherapy delays and dose reductions in non-Hodgkin lymphoma (NHL) patients treated with cyclophosphamide, doxorubicin, vincristine, and prednisone with or without rituximab (R±CHOP) who were provided with pegfilgrastim on the same-day of chemotherapy versus the standard 24-72h post-chemotherapy time window.

Methods: Six databases were searched for studies that compared same-day pegfilgrastim with the standard regimen in NHL patients. Given the low heterogeneity (I 2<50%, Cochrane Q test P>0.10, fixed-effect model was used to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs) for all outcomes of interest.

Results: We identified 7 studies, including one clinical trial (Burris et al. 2010) and six retrospective cohort studies (Woods et al. 2010, Ibrahim et al. 2011, Karol et al. 2013, Cheng et al. 2014, Bartels et al. 2021, McBride et al. 2021), that evaluated same-day versus standard 24-72h administration of pegfilgrastim in NHL patients. Results were statistically non-significant for all outcomes (Figure 1): FN across all chemotherapy cycles (OR=1.48, 95%CI= 0.98-2.23, P=0.06, N of studies=7); FN after the first cycle (OR=1.98, 95% CI=0.80-4.90, P=0.14, N=4); CIN grade 4 across all cycles (OR=0.73, 95% CI=0.37-1.47, P= 0.38, N=3); CIN grade 4 after the first cycle (OR=2.58, 95%CI= 0.86-7.73, P=0.09, N=3); and chemotherapy dose delays or reductions (OR=2.25, 95%CI=0.42-11.97, P= 0.34, N=2).

Conclusion: In this independent study, the likelihood of developing FN and CIN grade 4 in the first cycle or across all chemotherapy cycles, and the likelihood of chemotherapy dose delays or reductions were statistically not different in NHL patients treated with R±CHOP and administered pegfilgrastim same-day or 24-72h post-chemotherapy. In the setting of NHL treated with R±CHOP, administering pegfilgrastim on the day of completion of chemotherapy may be a safe and effective method of prophylaxis.

Figure 1 Figure 1.

Disclosures

Alrawashdh: Genentech: Current Employment. McBride: BMS: Current Employment. Abraham: Matrix45, LLC: Current holder of individual stocks in a privately-held company.
Phage Display Functionally Defines Variants in the Von Willebrand Factor Platelet Binding Domain
Authors: Yee Andrew , Arslantas Guzel Melda , Dai Manhong , Meng Fan , Ginsburg David
Published: November 2021

Missense variants in the von Willebrand factor (VWF) platelet binding domain, A1, may pathologically hyperactivate or weaken interactions with its platelet receptor, GPIbα, and lead to von Willebrand disease (VWD) subtypes 2B or 2M, respectively. Variants identified in VWD patients and tested as recombinant VWF have supported genotype-phenotype associations and subtyping of VWD by genetic analyses. However, novel variants, most classified as variants of uncertain significance (VUS) are poorly defined. To functionally characterize a large subset of VWF A1 variants (P1254-L1460), we screened a phage display library for binding to a recombinant form of GPIbα used to clinically assess VWF platelet binding activity, GPIbM. Comprised of ~5x10 6 independent clones, the phage display library contained 1,427 unique, missense variants (~36% of all possible single amino acid substitutions) which could be scored for significant enrichment, depletion, or no change following selection for GPIbM binding. The enrichment of phage displayed VWD variants previously classified as VWD subtype 2B significantly segregated from reported 2M variants (mean fold change from preselected phage ~1.06 for 2B vs. ~0.68 for 2M, p < 0.005). To further validate these findings, five depleted, four unchanged, and seven enriched VWF A1 variants were introduced into the full length VWF sequence by site-directed mutagenesis and expressed by transient transfection of HEK293T cells. Conditioned media were collected and analyzed for VWF level (VWF:Ag) and activity (VWF:GPIbM). Of the sixteen variants examined, fourteen (87.5%) exhibited a VWF GPIbM:Ag ratio that was concordant with the phage display findings. Furthermore, the VWF GPIbM:Ag ratios were well correlated with the degree of enrichment by phage display (Pearson R = 0.69, p< 0.01). Taken together, these findings demonstrate phage display as a high content approach to measure and functionally define the platelet-binding activity of genetic variants within the VWF A1 domain.

Disclosures

Ginsburg: Takeda: Patents & Royalties.
Microbiota Signals Suppress the Lymphoid Specification of Hematopoietic Stem Cells
Authors: Krambs Joseph R. , Monlish Darlene A. , Gao Feng , Schuettpelz Laura G. , Link Daniel C.
Published: November 2021

Aging is associated with an expansion of phenotypic hematopoietic stem cells (HSCs) with reduced self-renewal capacity and myeloid-skewed lineage differentiation. Signals from commensal flora support basal myelopoiesis in young mice; however, their contribution to hematopoietic aging is largely unknown. Here, we characterize hematopoiesis in young and middle-aged mice housed under specific pathogen free (SPF) and germ-free (GF) conditions. We did not analyze older mice due to the difficulty in maintaining mice in a gnotobiotic facility for more than one year. Consistent with prior studies, there is a shift in hematopoiesis in aged SPF mice towards granulopoiesis, with a significant increase in the percentage of granulocytic cells and a decrease in B lineage cells in the bone marrow. The marked shift from lymphopoiesis to myelopoiesis that develops during aging of SPF mice is mostly abrogated in GF mice. Compared with aged SFP mice, there is a marked expansion of B lymphopoiesis in aged GF mice, which is evident at the earliest stages of B cell development.

To investigate the impact of microbiota signals on multipotent HSPCs, we first quantified HSPCs by flow cytometry (Figure 1A-B). In aged SPF mice, the number of lineage - Sca1 + cKit + CD150 + CD48 - (LSK-SLAM) cells and CD34 - LSK-SLAM cells is increased 6.4 ± 1.7-fold and 3.4 ± 1.2-fold, respectively. Similar increases were observed in aged GF mice, with LSK-SLAM increasing 5.3 ± 1.6-fold (p=NS compared to SPF mice) and CD34 - LSK-SLAM cells increasing 2.8 ± 0.31-fold (p=NS). To quantify functional HSCs, limiting dilution transplantation experiments using unsorted bone marrow cells was performed. Although on a per cell basis the repopulating activity of aged HSCs is reduced, due to the large increase in phenotypic HSCs, the number of functional HSCs actually increases with aging, with similar increases in functional HSCs in aged SPF and GF mice (Figure 1C). Finally, to assess lineage-bias, we transplanted a limiting number of sorted HSCs and assessed lineage output. As expected, in young SPF mice, the majority of HSCs displayed a balanced myeloid/lymphoid lineage output, with a significant increase in myeloid-biased HSCs observed with aging (Figure 1D). In young GF mice, the majority of HSCs are lymphoid-biased. Moreover, although the myeloid output increased modestly with aging, the majority of HSCs in aged GF remained lymphoid-biased or balanced. Consistent with these data, RNA expression profiling of phenotypic HSCs from aged GF mice show enrichment for non-myeloid biased HSCs. Surprisingly, the RNA expression profiling data also suggest that inflammatory signaling is increased in aged GF HSCs compared with aged SPF HSCs. Collectively, these data suggest that microbiota-related signals suppress the lymphoid potential of HSCs, contributing to the expansion of myeloid-biased HSCs that occurs with aging.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.
The Krüppel-like Factor 4 Sustains a Leukemic Gene Expression Profile in MLL-AF9-Driven Acute Myeloid Leukemia
Authors: Lewis Andrew , Bridges Cory Seth , Moorshead David , Du Wa , Zorman Barry , Sumazin Pavel , Puppi Monica , Lacorazza H. Daniel
Published: November 2021

Among hematological malignancies, acute myeloid leukemia (AML) confers poor prognosis and limited progress has been made in the translation of decades of research into improved clinical outcomes. The current paradigm is that eradication of leukemia stem cells (LSCs) represents an avenue for overcoming relapse and refractory disease, but therapy focusing on eradicating this leukemic population has not been developed to-date. Further studies of unique signaling pathways and vulnerabilities in LSCs are warranted to design targeted therapies that could impact patient outcomes. To evaluate whether the stemness transcription factor Krüppel-like Factor 4 (KLF4) is important in the progression of AML, we retrovirally transduced MLL-AF9 into Klf4 fl/fl(fl/fl)and Klf4 fl/flVav-Cre (Δ/Δ) lineage − Sca-1 + c-Kit + (LSK) bone marrow cells and transplanted into C57BL/6 recipients. Here we report that the KLF4 promotes disease progression in the MLL-AF9-driven syngeneic AML mouse model. Strikingly, Δ/Δ AMLs exhibited improved disease latency and penetrance, and a seven-fold reduction in leukemia-initiating cell frequency in a secondary transplantation study. Δ/Δ LSCs, defined as leukemic granulocyte macrophage progenitors (L-GMP), demonstrated lessened clonogenicity in methylcellulose cultures and reduced representation of cells in the G 2/M phase of the cell cycle. RNAseq analysis of L-GMP revealed decreased expression of hematopoietic and leukemic stemness gene sets such as RAS signaling, and induction of inflammatory response gene (TNF-α, IFNα, IFNβ) pathways in Δ/Δ LSCs. To evaluate human relevance, we used CRISPR-Cas9 based targeted deletion of the human KLF4 gene in a MLL-AF9 PDX line and observed improved survival and defects in expansion as seen in the syngeneic mouse model . Lastly, to correlate KLF4-associated signaling present in murine AML LSCs with human AML, we used CRISPR-Cas9-based targeted deletion of KLF4 in MOLM-13 (KO) to generate two validated clones. MOLM-13 KO cells showed reduced cell proliferation in vitro and in vivo. Further, RPPA analysis revealed reduced RAS pathway activity (IR-β, β-Raf), accumulation of proteins associated with the S and G 1 phases (e.g., CDKN2A, p21, Histone H3, CENP-A), and decrease expression in regulators of the G 2/M checkpoint (e.g., Aurora A, B, Chk1, Plk1, Wee1, Cyclin B, pCDK1). Collectively, our data suggest a mechanism in which KLF4 contributes to AML disease by establishing a gene expression profile supporting stemness of AML LSCs.

Disclosures

No relevant conflicts of interest to declare.
In Depth Analysis of Blastic Plasmacytoid Dendritic Cell Neoplasm Based on a Comprehensive Literature Database of Cases
Authors: Ohgami Robert S. , Aung Phyu , Gru Alejandro Ariel , Hussaini Mohammad O , Querfeld Christiane , Yao Kelou , Small Corinn , Gollapudi Sumanth , Jaye David L , Wang Sa A , Pullarkat Sheeja T , George Tracy I.
Published: November 2021

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with poor outcome. BPDCN diagnostically overlaps with entities such as acute myeloid leukemia, histiocytic/dendritic cell neoplasms, and NK/T cell lymphomas. Unfortunately, large patient centered studies that comprehensively analyze clinical, pathologic and other diagnostic features are lacking. As such, there is an incomplete understanding of this disease. To better characterize BPDCN, a multicenter working group consisting of hematopathologists and dermatopathologists gathered in-person and remotely to review the current understanding of BPDCN, discuss specific issues regarding the diagnosis and differential diagnosis, and perform a retrospective analysis of the literature. A curated database of published BPDCN patient cases (BPDCN Network literature database) was generated. By conducting an in-depth analysis, not only did we confirm known findings in BPDCN such as frequent skin involvement and male predominance amongst older patients, but we also identified a number of under-recognized features, such as significant central nervous system involvement (35% of cases), and a roughly equal female to male prevalence amongst patients < 40 years old. Furthermore, with the large database, we were able to accurately summarize the immunohistochemical, cytogenetic, and molecular features of this disease. The BPDCN Network literature database serves as a central data repository of archived published aggregated and individual cases and facilitates an in-depth characterization of this rare disease. Continual updates from the consortium and beyond will allow for prospective refinement of our understanding of this orphan disease.

Disclosures

Ohgami: Stemline Therapeutics: Research Funding. Aung: Stemeline Therapeutics: Honoraria. Gru: Innate Pharma: Research Funding; StemLine: Honoraria, Research Funding, Speakers Bureau; CRISPT Therapeutics: Research Funding. Hussaini: Stemeline Therapeutics: Honoraria. Jaye: Stemline Therapeutics: Honoraria. Wang: Stemline Therapeutics: Honoraria. Pullarkat: Stemline Therapeutics: Honoraria. George: Bristol Meyers Squibb: Consultancy; Incyte Corporation: Consultancy; Blueprint Medicines: Consultancy; Celgene: Consultancy.
Transfusional Iron Overload in Sickle Cell Patients:Outcomes of Chelation Therapy
Authors: Adamkiewicz Daniel , Mangaonkar Abhishek A. , Son James , Xu Hongyan , Wells Leigh , Bowman Latanya , Kutlar Abdullah
Published: November 2021

Iron (Fe) overload is not rare among sickle cell disease (SCD) patients. It results from either chronic transfusions for primary or secondary stroke prevention, or more commonly sporadic, mostly unnecessary transfusions and are associated with significant morbidity, secondary to hepatic, cardiac and renal Fe deposition. Previous studies at our Center showed that 12% of the adult SCD population had Fe overload, and vast majority of these (80%) resulted from episodic transfusions (Son et al, 2013). Subsequent studies showed that the Fe regulatory peptide, hepcidin was appropriately upregulated in SCD subjects with Fe overload, and the plasma levels of the glycoprotein hormone erythroferrone (ERFE) was not as high as that found in patients with transfusion dependent beta thalassemia (TDT) due to the absence of significant ineffective erythropoiesis in SCD (Thawer et al, 2017, Mangaonkar et al, Brit. J. Haematol, 2020). We report on the utilization and outcomes in Fe overloaded SCD patients who were prescribed the oral chelating agent deferasirox.

22 patients were prescribed deferasirox; median age was 38, 12 female 10 male. 21 had Hb SS, and 1 had s-b 0 thalassemia. Deferasirox dose ranged from 720-2500 mg/day (12 to 28 mg/Kg/day). Nonadherence was ascertained by patients' own admission. Figures 1-3 show the pre and post ferritin levels in subjects who were on deferasirox, and in controls; patients who took deferasirox had a more pronounced decrease in their ferritin (p=.004 vs p=.74). Although hepatic MRI for liver iron content (LIC) was not available on all patients, in those who underwent MRI there was a correlation between LIC and serum ferritin obtained at close temporal proximity (Fig. 4). Most common side effects of deferasirox were gastrointestinal (abdominal pain, nausea, vomiting, diarrhea), which were seen less commonly with the newer oral formulation (Jadenu).

Several conclusions can be drawn from our observation on relatively small number of patients: 1) Deferasirox is effective in decreasing Fe overload as shown by serum ferritin levels 2) Second generation of oral deferasirox is better tolerated, and therefore is associated with improved adherence, 3) Documentation of a decrease in LIC with chelation will be important for the reversal of Fe induced organ damage, and 4) Parallel studies of the levels of Fe regulatory peptides hepcidin and erythroferrone (ERFE) will clarify the effect of chelation therapy on biomarkers of Fe metabolism.

Figure 1 Figure 1.

Disclosures

No relevant conflicts of interest to declare.