bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Systematic Review on Efficacy and Safety of Bortezomib Based Regimens for Treatment of Waldensterom Macroglobulinemia
Authors: Dar Abdul Jabbar , Khurshid Qasim , Ahmad Muhaddis Ejaz , Mirza Muhammad Ali , Khalid Farhan , Jaan Ali , Abdullah Syed Maaz , Farooqi Muhammad Saad , Khan Atif Irfan , Kashyap Richi , Khan Anam , Javed Saad , Qamar Fazeel , Anwer Faiz 
Published: November 2020

Introduction:
Waldenström macroglobulinemia (WM) is a B-cell lymphoproliferative disorder characterized by lymphoplasmacytic bone marrow infiltration and immunoglobulin M (IgM) monoclonal gammopathy. Various studies have shown that the proteasome inhibitor bortezomib (V) targets signaling pathways of relevance in WM. We reported published data on the efficacy profile of (V) for the patients of WM.
Methods:
We performed a comprehensive literature search on articles following PRISMA guidelines. Beginning with articles published after 2004, we used databases like PubMed, Embase, Clinicaltrials.gov, Cochrane Library and Web of Science. Total 580 articles were identified initially and after detailed screening, we finalized 9 studies involving 375 patients with Waldenstrom Macroglobulinemia (WM) treated by combination of Bortezomib.
Results:
The total number of patients in the studies involving Bortezomib were 375 and dose of the drug used ranged between 1.3 mg/m2 to 1.6mg/m2. The Complete response (CR) ranged from 0-19% and the partial response (PR) ranged from 44-58%.
Bortezomib(V):
In the study Treonet et al., N=27, the highest major respose rate was 85% and minimal response rate was 37%. In the study Chen et al., N=27, the major response rate was 26% and the PR was 44%. Progression free survival (PFS) was 16.3 months for Chen et al.
Bortezomib(V), Rituximab(R), and Dexamethasone(D):
In the study Treon et al., N=23, the highest major response rate was 96%, CR was 13%, Very good partial response (VGPR) was 13%, and PR was 46%. Highest PR and was observed in Dimopolous et al., which was 58% and 42 months respectively.
Bortezomib(V), and Rituximab(R):
In the study Agathocleus et al., N=42, the highest CR was 14.2-19%. The highest PR was between 47.6-52.3%. In the study Ghobrial et al., N=37, the CR was 3% and PR was 46%. PFS was 15.6 months.
Bortezomib(V), Rituximab(R) and Everolimus(E):
In the study Ghobrial et al., N=46, the CR was 4%, PR was 46% and PFS was 18 months.
Conclusion:
Despite heterogenicity in WM patients and various regimens used in literature, Bortezomib containing regimens are a remarkably effective treatment. Combination regimens showed an overall response rate of 96%. The main side effects being anemia, leukopenia, thrombocytopenia, nausea and sensory neuropathies. Although we recommend future randomized prospective trials to better understand the efficacy and safety profile of Bortezomib for WM treatment.

Disclosures
Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.:Honoraria, Research Funding, Speakers Bureau.
Plasma Cell-Free DNA Chromosomal Instability As Surrogate Biomarker of Treatment Response and Minimal Residual Diseases for Multiple Myeloma
Authors: Du Juan , Chen Baoan , Qiang Wanting , Jia Yanchun , Lu Jing , Li Lu , Liu Jing , Jiang Hua , Qian Ziliang , Fu Weijun 
Published: November 2020

Background: Minimal residual disease (MRD) is becoming standard diagnostic care for multiple myeloma. Here we investigate cell-free DNA chromosomal instability as minimal invasive biomarker for minimal residual disease monitoring.
Methods: 55 patients were recruited, including 47 newly diagnosed and 8 relapsed multiple myelomas. Plasma samples were collected before treatments, end of 2 cycle and 4 cycle of treatments. Treatment response was assessed by using IMWG criteria. Cell-free DNA was analyzed by illumine HiSeq X10, followed by chromosomal instability analyses by a customized bioinformatics workflow, ultrasensitive chromosomal aneuploidy detector (UCAD), and cfDNA CIN responding to treatment was summarized as cfDNA MRD INDEX.
Results: In this cohort study, 53 (96.3%) patients were found with treatment responses after 4 cycle of treatments, including 16 (29.1%) complete, 13 (23.6%) very good partial, 17 (30.9%) partial and 6 (10.9%) marginal responses. The other 2 (3.64%) recurrent MM experiences disease progression.
At baseline, plasma cfDNA chromosomal aberrations were found in 14/17(82.3%) multiple myeloma patients. Less patients were found with detectable chromosomal changes after treatments (58.8% after C2, 41.2% after C4, versus 82.3% before treatments, P&lt;0.01). The treatment responses identified in plasma cfDNA were summarized as cfDNA MRD INDEX. Low cfDNA MRD INDEX predicts better treatment responses (Fisher exact test, Odds ratio=7.3, P=4.69e-05). And it predicts complete response with sensitivity 100% and specificity 83.3%, with cutoff value 0.044.
Furthermore, cfDNA CIN MRD index were found linearly correlated with percentage of malignant plasma cells from bone marrow aspiration as examined by flow cytometry assay (R-square=0.883, P&lt;0.01). Cutoff -0.06 predicts 100% MRD negatives at specificity 100%.
Conclusions: Plasma cfDNA CIN might be used for monitoring multiple myeloma patients treatment responses, especially for predicting minimal residual diseases.

Disclosures
No relevant conflicts of interest to declare.
Preferential Usage of Specific Immunoglobulin Heavy Chain Variable Region Genes with Unmutated Profile and Advanced Stage at Presentation Are Common Features in Patients with Chronic Lymphocytic Leukemia from Senegal
Authors: Sall Abibatou , Amato Teresa , Gozzetti Alessandro , Touré Awa Oumar , Diop Saliou , Leoncini Lorenzo , Piccaluga Pier Paolo , Raphaël Martine 
Published: November 2020

Introduction : Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western populations, being rarer in Asian and African people. It has been suggested that patients with CLL from Africa might have a more aggressive disease compared with Causasien patients. In this study, we aimed to identify genetic factors that may account for this difference
Methods: We collected peripheral blood mononuclear cells (PBMCs) from a total of 75 patients with CLL, 25 from Senegal (Africa), and 50 from Siena. Since it is well known that there are differences in germline IGH repertoires between different populations, we also collected PBMCs from five healthy Senegalese individuals as control. We analyzed immunoglobulin heavy chain (IGH) genes mutational status by performing next-generation sequencing in these 2 groups of patients.
Results: We found that Senegalese patients more frequently had adverse prognostic factors and an unmutated profile. Furthermore, we documented that IGHV1 (IGHV1-69), IGHD3, and IGHJ6 were significantly more frequent in Senegalese patients, whereas IGHV3-30 was common and limited to the Italian cohort. Stereotyped receptors commonly detected in the white population were not recorded in our Senegalese series.
Conclusion: The different IGH repertoire we observed in the Senegalese cohort may reflect the diverse genetic and microenvironmental (ie, polymicrobial stimulation) background.

Disclosures
Gozzetti: Takeda: Honoraria; Amgen: Honoraria; Janssen: Honoraria, Research Funding.
Ikaros Expression in the Graft Is Associated with Chronic Graft Versus Host Disease
Authors: Pereira Andre Domingues , de Molla Vinicius Campos , Da Fonseca Ana Rita , Novis Yana , Pires Marcela Souza , Popi Ana , Arrais-Rodrigues Celso 
Published: November 2020

Introduction: Hematopoietic stem cell transplantation (HSCT) is the only potentially curative treatment for several diseases. Immune reconstitution post HSCT is a complex and extremely variable process. Ikaros transcription factor has an important role in hematopoiesis of several cell lines, especially in the lymphoid compartment. We hypothesized that Ikaros expression, both in the graft and in the recipient after transplant, might influence immune reconstitution and, consequently, the risk of opportunistic infections, relapse, and graft versus host disease (GVHD).
Objectives: To correlate Ikaros expression both in the graft and in the recipient's peripheral blood (PB) after engraftment with the risk of GVHD after allogeneic HSCT outcomes.
Patients and methods: 51 patients were included. Median age was 51 years (19-80), 53% of patients were male, and 57% of them had acute leukemia. Donor were haploidentical in 45% of cases, related identical in 29% and unrelated identical in 26%. Most patients (82%) received reduced-intensity conditioning regimens. Median follow-up was 20 months (10-40 months). Samples were collected from the graft and from the PB of the recipient 3 weeks after neutrophil recovery. Real time polymerase chain reaction (RT-PCR) was performed for analysis of absolute and relative Ikaros expression.
Results: There was no association between Ikaros expression and the risk of acute GVHD, relapse or mortality. However, a significant association was observed in the risk of chronic GVHD. Cumulative incidence (CI) of chronic GVHD and of moderate / severe chronic GVHD (according to National Institute of Health - NIH classification) in two years were 49% and 28%, respectively. Higher Ikaros expression in the graft was associated with a significantly higher risk of moderate/severe chronic GVHD (54% vs. 15%, respectively, P=0.01). Higher Ikaros expression in the recipient's PB after engraftment was also associated with a significantly higher risk of moderate/severe chronic GVHD (65% vs. 11%, respectively, P=0.01).
Conclusions: Ikaros expression in the graft and in the PB of the recipient after transplant seems to be correlated with a higher risk of moderate/severe chronic GVHD and might be evaluated in larger and prospective trials as a potential biomarker.

Disclosures
No relevant conflicts of interest to declare.
TWIST1 Preserves Hematopoietic Stem Cell Function Via Repression of Cacna1b Expression
Authors: Wang Nan , Yin Jing , You Na , Guo Dan , Zhao Yangyang , Ru Yongxin , Liu Xiaoyan , Cheng Hui , Ren Qian , Cheng Tao , Ma Xiao-Tong 
Published: November 2020

The mitochondria of hematopoietic stem cell (HSC) play crucial roles in regulating cell fate and in preserving HSC functionality and survival. However, the mechanism underlying its regulation remain poorly understood. Here, we identify transcription factor TWIST1 as a novel regulator of HSC maintenance through modulating mitochondrial function. We demonstrate that Twist1 deletion results in a significantly decreased long-term HSC (LT-HSC) frequency, markedly reduced dormancy and self-renewal capacities and skewed myeloid differentiation in steady-state hematopoiesis. Twist1-deficient LT-HSC are more compromised in tolerance of irradiation and 5 fluorouracil-induced stresses, and exhibit typical phenotypes of senescence and higher levels of DNA damage and apoptosis. Mechanistically, Twist1 deficiency upregulates the expression of voltage-gated calcium channel Cacna1b in HSC, leading to noticeable increases in mitochondrial calcium levels, biogenesis, metabolic activity and reactive oxygen species production. Suppression of voltage-gated calcium channel by a calcium channel blocker largely rescues the phenotypic and functional defects in Twist1-deleted HSCs under both steady-state and stress conditions. Collectively, our data, for the first time, characterize TWIST1 as a critical regulator of HSC function acting through CACNA1B/Ca2+/mitochondria axis, and highlight the importance of Ca2+ in HSC maintenance. These observations provide new insights into the mechanisms for the control of HSC fate.

Disclosures
No relevant conflicts of interest to declare.
Study of the Role of Splicing Factor SRRM2 in Cytarabine Treatment Resistance in Acute Myeloid Leukemia
Authors: Morales María Luz , Garcia-Vicente Roberto , Álvarez Sánchez-Redondo Noemí , Rodríguez García Alba , Ortiz-Ruiz Alejandra , Reyes-Palomares Armando , Hermouet Sylvie , Ayala Rosa , Martinez-Lopez Joaquin , Linares María 
Published: November 2020

Introduction. Acute myeloid leukemia (AML) is a very complex and dynamic disease, characterized by clonal expansion of aberrantly differentiated myeloid lineage blasts. Although in recent years the molecular mechanisms involved in the development of the disease have been deeply studied, and as result many new targets have emerged, the treatment has not changed substantially. 7+3 chemotherapy regimens remains as the treatment of choice in most cases. Refractoriness and relapse after reaching complete remission are the main cause of death in the disease. Therefore, to improve current treatments it is crucial not only to know the molecular profile of patients at diagnosis, but also to know the mechanisms of pharmacological resistance that may be developed, in order to propose more appropriate and personalized treatments.
Methods. The analysis of the proteomic profile associated to cytarabine treatment resistance of paired samples from 3 patients with AML was performed by LC-MSMS after IMAC enrichment. The OCI-AML3 cell line was used to generate a model of cytarabine resistance through sustained exposure to increasing doses of the drug, thus generating the OCI-AML3_R line (Figure 1A). Gene expression levels ofSRRM2were studied in the cell model (n=3), as well as in paired samples of AML patients (n=7) by qPCR; in addition to data deposited in public repositories from the TCGA-LAML and GTEx-BM projects. Finally, SR protein phosphorylation levels were studied in paired bone marrow smears by immunohistochemistry (n=7).
Results. Proteomic analysis of paired samples from AML patients has identified an increased in the phosphorylation of SRRM2, among other SR proteins, at the time of cytarabine resistance. Analysis of public data has revealed several mutations and copy number variations in genes related to the spliceosome. However, these studies, as well asin vitroanalysis, have rejected that changes in SRRM2 phosphorylation are due to changes in gene or protein expression (Figure 1B and 1C). Otherwise a significant increase in SR protein phosphorylation has been detected after the development of cytarabine resistance by immunohistochemistry (Figure 1D). This increase in phosphorylation is prominent at the time of diagnosis in patients showing treatment refractoriness.
Conclusions.The results obtained in this study show the involvement of the splicing pathway in AML and in cytarabine resistance. In addition, the immunohistochemistry analysis suggests a role of the phosphorylation levels of SR proteins as a possible predictive biomarker of response to cytarabine treatment.

Disclosures
No relevant conflicts of interest to declare.
Thalidomide Plus Prednisone and Methotrexate for Symptomatic Large Granular Lymphocyte Leukemia: A Prospective, Single-Center, Pilot Study
Authors: Yi Shuhua , Du Jun , Yu Ying , Jiao Yang , Wang Yi , Wang Huijun , Wang Tingyu , Lv Rui , Liu Wei , Xiong Wenjie , Liu Huimin , Huang Wenyang , Zou Dehui , An Gang , Zhao Yaozhong , Wang Jianxiang , Qiu Lugui 
Published: November 2020

Background: Large granular lymphocyte leukemia (LGLL) is one type of chronic lymphocytic proliferative disorders, which commonly manifests as infiltration of large granular lymphocytes in both peripheral blood and bone marrow. LGLL now includes two entities with similar clinical course, treatment strategy and outcomes: T-cell large granular lymphocytic leukemia and chronic lymphoproliferative disorder of NK cells. The standard therapy for LGLL is still elusive. Here, we presented the efficacy and safety of combinatorial oral immunoregulatory regimen thalidomide, prednisone, and methotrexate (TPM regimen) in a prospective phase 2 clinical trial. Methods: We designed this phase 2 investigator-initiated clinical trial (NCT04453345) to evaluate the clinical response and safety of the combination of thalidomide, prednisone, and methotrexate in symptomatic treatment naïve LGLL patients. The TPM regimen includes thalidomide 50-100mg per night, prednisone 0.5-1.0mg/kg qod and methotrexate 10mg/m2 per week. This regimen will be administrated for up to 12 months until disease progression or intolerable. Then, thalidomide maintenance will continue for another year or until intolerance. Meanwhile, we set Cyclosporin A (CsA) alone or plus steroids as control. Treatment dosage for CsA was 3-5mg/Kg/day with or without steroids (prednisone) 0.5-1 mg/Kg/day. The primary endpoint of this study was the complete response rate. Results: From Aug 2013, to Jan 2020, twenty-eight patients were enrolled in this study. The median follow-up time was 26 months (range: 7-96). Twenty-five patients (89%) achieved hematologic and symptomatic response. Among them, 21 patients (75%) achieved complete response (CR) and four patients achieved partial response. The median time to best clinical response was 6 months (2-18). The 3-years progression-free-survival (PFS) rate was 90%, and 3-years overall survival (OS) rate was 92%. The median PFS time was not reached in TPM group. The curative effect was better for TPM treatment group, both for overall response (OR) (TPM 89% (25/28) vs CsA 49% (49/99), P=0.000) and CR (TPM 75% (21/28) vs CsA 20% (20/99), P=0.000). Adverse events were uncommon, two patients had grade 1-2 nausea and one had grade 3 nausea. Two patients had grade 1-2 constipation and one patient experienced grade 1-2 peripheral neuritis. Conclusion: The efficacy of this TPM regimen is higher than the history reports with limited adverse events. The multiple-center clinical trial has been initiated to validate this conclusion.

Disclosures
No relevant conflicts of interest to declare.
Investigating the Dual Targeting of BCL-2 and CD38 in Models of Acute Myeloid Leukemia
Authors: Mistry Jayna J , Hellmich Charlotte , Lambert Amelia , Moore Jamie A , Jibril Aisha , Collins Angela , Di Palma Federica , Bowles Kristian M , Rushworth Stuart A 
Published: November 2020

Acute myeloid leukemia (AML) is correlated with poor prognosis and a high mortality. Current AML treatment often fails to achieve complete remission and relapse is common, highlighting the need for more targeted treatments. Overexpression of BCL2 is a hallmark of AML progression and is often associated with a poor response to cytotoxic treatment. BCL2 inhibition by the BH3 mimetic Venetoclax has been shown to be effective in promoting AML cell death and recently Venetoclax has received FDA approval for the treatment of AML. However, some patients do not respond or can develop resistance, therefore multiple studies for combinational therapies for Venetoclax have been researched. We have previously demonstrated CD38 inhibition by daratumumab treatment inhibits mitochondrial transfer from mesenchymal stromal cell (MSC) to AML blasts in the bone marrow (BM) microenvironment, which results in a reduction in AML derived oxidative phosphorylation and subsequent reduced leukemia growth and improved animal survival. We therefore investigated the consequences of inhibiting CD38 using daratumumab and BCL2 using Venetoclax on the AML survival.
Primary AML blasts were isolated from patient's BM. CD38 expression and BCL2 expression was assessed by flow cytometry analysis of AML. AML had significantly higher BCL2 expression and a slight increase in CD38 expression compared to CD34+ cells. Venetoclax alone caused a significant decrease in cell viability, however daratumumab or in combination with Venetoclax had no additive effect on AML survival. Since AML is highly reliant on the BM microevironment we cultured AML on MSC with either Venetoclax alone, daratumumab alone, or Venetoclax and daratumumab for 24 hours. Cells were then stained with Annexin V-FITC/PI and analysed using flow cytometry. Cells underwent significantly more apoptosis in the combination Venetoclax and daratumumab treatment when compared to control AML cells.
To determine the effect of Venetoclax and daratumumab treatment in preclinical models we used an NSG xenograft mouse model of AML, we transplanted MV411-luc or patient derived AML and treated the animals with either vehicle control (PBS) daratumumab (5mg/kg) on day 7 and 14 alone, Venetoclax (100mg/kg/day) alone, or both daratumumab and Venetoclax followed by bioluminescence imaging. In vivo, treatment with combination daratumumab and Venetoclax significantly reduced tumor burden and improved survival compared to control and either drug alone in the patient derived AML xenograft mouse model and in MV411.
These data support the further clinical investigation of Venetoclax and Daratumumab combination as a therapeutic approach for the treatment AML.

Disclosures
Bowles: AbbVie: Research Funding; Janssen: Research Funding. Rushworth:Janssen: Research Funding; AbbVie: Research Funding.
Nanoparticle-Directed Targeting of Clustered PSGL-1 Mitigates Neutrophil-Derived Thrombosis in Antiphospholipid Antibody Syndrome
Authors: Sweet David R , Thomas Asha , Lapping Stephanie D , Kalikasingh Kenneth A , Ortel Thomas L. , Jain Mukesh K , Maiseyeu Andrei , Nayak Lalitha V. 
Published: November 2020

Multiorgan thromboses and subsequent organ failure are among the more devastating consequences of antiphospholipid antibody syndrome (APS). APS poses a relatively unique risk to patients by virtue of its propensity to cause thrombi of both the arterial and venous vascular systems. While recent studies have explored mechanisms of thrombosis in singular vascular beds, there remains a dearth of targetable effectors of arteriovenous thrombosis in APS. Here, we examine the potential of neutrophils as key players of both arterial and venous thrombosis in APS. From this and previous studies, we have also identified a critical transcriptional regulator in neutrophils whose loss mimics arterial and venous thrombosis susceptibility seen in APS. This factor, Krüppel-like factor 2 (KLF2), is down regulated in APS patients as well as in cells treated with antiphospholipid antibody (APLA) ex vivo. Loss of KLF2 in neutrophils contributes to classic neutrophil activation phenotypes including NETosis, increased tissue factor release, and heightened chemotaxis; remarkably, blocking each of these functions greatly abrogates the thrombotic phenotype. Utilizing the myeloid KLF2 knockout (K2KO) system as a model for aberrant neutrophil activation seen in APS, we have identified clustering of P-selectin glycoprotein ligand 1 (PSGL-1) secondary to actin rearrangement to be operative in neutrophil-mediated thrombosis in arterial and venous systems. While neutralizing antibodies against PSGL-1 have been explored as therapeutic options in APS, there remains a challenge in establishing local specificity to activated immune cells in order to increase efficacy. To circumvent this, we have designed a nanoparticle (NP) based approach that utilizes NPs decorated with anti-PSGL-1 immunoglobulins to better target clustered PSGL-1 on activated neutrophils. PSGL-1 NPs are more effective at inhibiting neutrophil rolling and adhesion in in vitro assays while, incubating activated neutrophils in PSGL-1 NPs prior to infusion attenuates their ability to contribute to both arterial and venous thrombosis. Further, injection of PSGL-1 NPs directly into K2KO mice reduces their extensive thrombotic phenotype. Importantly, this effect occurs at a substantially lower dose of PSGL-1 NPs than that which would be needed of PSGL-1 antibody alone. Finally, PSGL-1 NPs greatly reduce thrombotic burden in mice injected with APLA, diminishing clotting in both arteries and veins. Together, this work identifies key molecular and cellular players in APLA-induced arteriovenous thrombosis. Furthermore, it provides early pre-clinical evidence at specifically targeting clustered PSGL-1 on neutrophils as a viable option in combatting thrombosis in this particularly vulnerable patient population.

Disclosures
No relevant conflicts of interest to declare.