bluuebunny/crossref_metadata_2025_split huggingface dataset:
OSU-A9, An Indole-3-Carbinol Derivative, Induces Cytotoxicity In Acute Myeloid Leukemia Through Reactive Oxygen Species-Mediated Apoptosis
Authors: Bai Li-Yuan , Weng Jing-Ru , Wu Chia-Yung , Chiu Chang-Fang , Yeh Su-Peng , Liao Yu-Min 
Published: October 2019

Abstract

Introduction
Indole-3-carbinol (I3C) is a broadly targeted phytochemical shown to prevent carcinogenesis in animal studies and to suppress the proliferation of cancer cells of human breast, colon, prostate, and endometrium. Here we aim to test the anticancer effect of OSU-A9, an I3C derivative with improved potency, in acute myeloid leukemia (AML).

Materials and Methods
The in vitro activity of OSU-A9 was evaluated in AML cell lines (HL-60 and THP-1) and primary leukemia cells from 18 AML patients. THP-1 xenograft tumors in athymic nude mice was used for in vivo study.

Results
OSU-A9 mediates cytotoxicity in AML cell lines and primary leukemia cells from AML patients in a dose-responsive manner. The IC50 at 24 h for 18 patients was 1.63 μM. Normal human bone marrow cells were much less sensitive to OSU-A9 with an IC50 at 24 h greater than 8 μM. OSU-A9 causes cytotoxicity dependent on caspase activation, as evidenced by caspase-3 and PARP cleavage, and induces autophagy but not autophagic cell death. Interestingly, pretreatment of AML cell lines and primary AML cells with N-acetylcysteine or glutathione rescues them from apoptosis (and concomitant PARP cleavage) and Akt hypophosphorylation, implicating a key role of reactive oxygen species (ROS) in OSU-A9-related cytotoxicity. To investigate the anti-leukemia effect of OSU-A9 in vivo, fifteen male athymic nude mice were xenografted with THP-1 cells. Briefly, the anticancer utility of OSU-A9 is extended in vivo as it, administered intraperitoneally, suppresses the growth of THP-1 xenograft tumors in athymic nude mice without obvious toxicity. For biomarker analysis in the THP-1 xenografts, protein extracts were obtained from the tumors and immunoblotted for Akt levels. The tumors from OSU-A9 treated mice exhibited down regulation of Akt phosphorylation compared with those from placebo-controlled mice.

Conclusions
This study shows that ROS-mediated apoptosis contributes to the anticancer activity of OSU-A9 in AML cell lines and primary AML cells, and thus should be considered in the future assessment of its translational value in AML therapy.

Disclosures:
No relevant conflicts of interest to declare.
Functional and Phenotypic Characterization Of Acute Myeloid Leukemia By Analysis Of Diagnostic/Relapse Paired Samples
Authors: Ho Jenny M. , Shlush Liran I. , Mitchell Amanda , Marke Rene , McLeod Jessica , Minden Mark D. , Dick John E. , Wang Jean C.Y. 
Published: October 2019

Abstract
Treatment of relapsed acute myeloid leukemia (AML) results in lower complete remission rates compared to treatment of AML at diagnosis. Immunophenotypic changes in leukemic blasts are common from diagnosis to relapse (Baer et al. Blood. 2001), suggesting that the underlying biology of AML changes with disease progression. A better understanding of the biologic properties of AML cells at different stages of disease will facilitate the development of biomarker tools and more effective therapies. We therefore studied paired diagnostic/relapse samples obtained from AML patients. Cells from 11 paired samples were transplanted into immune deficient mice (NOD.SCID IL2Rg null) over a range of cell doses. In 10 of 11 patients, a leukemic graft could be generated after transplantation of lower cell doses from the relapse sample compared to the paired diagnostic sample. By limiting dilution analysis, leukemia stem cell (LSC) frequency was higher in relapse samples (1 in 5.8×102 to 1 in 2.4×106, median 1 in 2.0×103) compared to diagnostic samples (1 in 5.0×103 to 1 in 6.1×106, median 1 in 5.5×104); the fold increase in LSC frequency ranged from 2.2 to 745 (median 8.6). Multiparameter flow cytometric analysis carried out on 13 paired diagnostic/relapse samples demonstrated an increase in 2 known stem cell markers, CD34 and CD117, from diagnosis to relapse: CD34 was gained or increased at relapse in 7/13 (54%) of paired samples, while CD117 was gained or increased at relapse in 9/13 (69%) of paired samples. We plan to take a comprehensive approach to examine the surface marker expression of paired diagnostic/relapse samples by a high throughput flow cytometric screen (HTS) of both bulk and LSC-containing AML populations to identify markers that are altered at relapse. As a first step, we have performed HTS of 373 surface markers on 10 AML patient samples, including a relapse sample from a diagnostic/relapse pair. A significant proportion of markers (155/373, 42%) were expressed on less that 5% of cells in all 10 AML samples analyzed. We will therefore focus on the remaining markers in our HTS analysis of paired samples. Surface markers that are differentially expressed from diagnosis to relapse will be further characterized in order to gain insight into disease progression and identify potential therapeutic targets.

Disclosures:
No relevant conflicts of interest to declare.
Anticoagulation Prophylaxis With Enoxaparin For Patients With Acute Lymphoblastic Leukemia Receiving Asparaginase-Based Intensification Therapy
Authors: Sibai Hassan , Seki Jack T , Atenafu Eshetu G , Yee Karen W.L. , Schuh Andre C , Gupta Vikas , Minden Mark D. , Schimmer Aaron D. , Brandwein Joseph M. 
Published: October 2019

Abstract

Background
Venous thromboembolism (VTE) is a well-known complication in patients treated with asparaginase-containing regimens; the optimal preventative strategy is unclear. We assessed the safety and efficacy of low-dose low molecular weight heparin (LMWH) prophylaxis in adult patients with newly diagnosed acute lymphoblastic leukemia (ALL) treated with an asparaginase- based regimen.

Methods
Patients were treated with the DFCI 91-01 protocol from 2009-2012; patients age 60 and over received a modified version. All patients who were in complete remission and received at least 7 cycles (21 weeks) of the asparaginase-based intensification phase were evaluable for analysis. Patients already on anticoagulation for prior VTE were excluded. Patients received enoxaparin subcutaneously once daily, at a dose of 40 mg for patients weighing less than 80 kg and 60 mg for those 80 kg and over, beginning on day 1, cycle 1 of intensification until the completion of the entire 21-30 week intensification phase. Results were compared to a similar cohort of consecutive patients treated with the same protocol prior to 2009, without anticoagulation prophylaxis.

Results
There were 41 evaluable patients who received enoxaparin prophylaxis. The historical cohort (n=99) did not significantly differ from this group with respect to median age, weight and number of treatment cycles per patient. The mean enoxaparin dose administered was 0.62 mg/kg (range 0.39-1.05 mg/kg). As shown in Table 1, the overall rate of VTE was not significantly different than the historical non-prophylaxed cohort. Among patients receiving prophylaxis, there was a higher rate of VTE in patients who weight at least 80 kg, despite the higher enoxaparin dose used (p=0.036). There was no significant difference in the rate of VTE according to age or gender. Sites of VTE in the prophylaxed group included lower extremity (8 cases), sagittal sinus (2), subclavian line related (2), and pulmonary embolism (6). There were no major bleeding complications observed in the prophylaxed group (minor bleeding 3/41).

Conclusions
Prophylaxis with low-dose enoxarain during the intensification phase was safe, but did not show a significant benefit in reducing the rate of VTE. Prospective randomized studies are needed, using more intensive or novel prophylaxis strategies, in adult ALL patients treated with asparaginase-containing regimens.

Disclosures:
Off Label Use: enoxaparin for VTE prophylaxis in ALL.
Duration Of Neutropenia Is Associated With Reduced Relapse Risk In Children With De Novo Acute Myeloid Leukemia: A Report From The Children’s Oncology Group
Authors: Sung Lillian , Aplenc Richard , Alonzo Todd A. , Gerbing Robert B. , Meshinchi Soheil , Gamis Alan S. 
Published: October 2019

Abstract

Background
Children receiving treatment for de novo acute myeloid leukemia (AML) commonly experience infections and prolonged duration of neutropenia. There is great variability in these outcomes and pharmacogenomics may provide one mechanism to explain this variability. We hypothesized that relapse outcomes may be inversely related to the degree of toxicity.

Objectives
To describe the relationship between the number of sterile site infections and duration of neutropenia during the first four cycles of chemotherapy and the risk of recurrence and overall survival.

Methods
AAML0531 was a Children's Oncology Group (COG) randomized phase 3 clinical trial that included 1022 children with de novo AML enrolled between August 2006 and June 2010. Inclusion criteria were age ≥ 1 month to ≤ 30 years. For this specific analysis, we focused on non-Down syndrome patients who completed at least 4 cycles of chemotherapy on protocol therapy without recurrence on therapy and who did not receive HSCT in first remission. Because high-risk patients were allocated to best allogeneic donor HSCT, we focused on favorable and intermediate risk cytogenetic groups. The treatment protocol consisted of 5 cycles of intensive chemotherapy; patients were randomized to receive or not receive gemtuzumab ozogamicin (GMTZ) during Induction I and Intensification II.
The cumulative time to neutrophil recovery between start of Induction II and completion of cycle 4 (Intensification II) was examined; Induction I was not included since many centers did not wait for neutrophil recovery before starting Induction II. Relapsed risk and survival analyses were conducted from the end of Intensification II. Potential confounders explored for this analysis were gender, age, race, weight group, cytogenetic risk group and allocation to GMTZ.

Results
There were 569 patients included; 279 (49.0%) were male and 210 (36.9%) had favorable risk cytogenetics. There were 1116 sterile site infections; 735 (65.9%) were Gram-positive bacteria. The median cumulative time with neutropenia was 96 (range 46 – 204) days. The Table illustrates that infections did not significantly influence the risk of relapse or overall survival. However, increased duration of neutropenia was associated with a lower risk of relapse both in univariate and multiple regression models after adjustment for African-American race, favorable risk cytogenetics and GMTZ allocation.

Conclusions
Longer duration of neutropenia is associated with a reduced risk of relapse for children with favorable and intermediate cytogenetic risk AML. Toxicity may be mediated through pharmacogenomics which suggests that individualized chemotherapy dosing may be an effective strategy.

Disclosure:
No relevant conflicts of interest to declare.
Nanoparticle Encapsulated L-Asparaginase
Authors: Ortac Inanc , Ruff Laura , Yeh Yasan , Esener Sadik , Messmer Bradley T 
Published: October 2019

Abstract
Amino acid depletion with catabolizing enzymes is a potential therapeutic modality for many cancer types. L-asparaginase has been used to treat Acute Lymphoblastic Leukemia (ALL) for many decades and is part of treatment regimen that has a roughly 80% cure rate. The current frontline formulation is L-asparaginase from E.coli that has been conjugated to polyethylene glycol (PEG) for extended circulation half life and protection from immune responses. However, neutralizing antibodies still occur in a subset of patients, necessitating a switch to a different L-asparaginase, such as the less active enzyme from Erwinia chrysanthemi. This complicates therapy, risks severe allergic reactions, and if antibodies develop to the second enzyme the options become limited. The threat of immune reactions, as well as other side effects, has largely restricted L-asparaginase therapy to ALL, despite in vitro evidence that many other cancers might be sensitive to asparagine depletion.
Our group has developed a novel nanoparticle enzyme encapsulation technology that overcomes the limitation of immune responses to enzymes or PEG. These particles, termed Synthetic Hollow Enzyme Loaded Porous nanoShells (SHELS), are produced in a two-step process where the first creates silica shells with large pores through which the enzyme can be loaded, and a second sealing step that encapsulates the mesoporous shell and the loaded enzyme cargo with a nanoporous silica layer. The work below was done with 200nm particles that have a total shell wall thickness of approximately 10nm.
SHELS were loaded with L-asparaginase (Elspar). No loss of activity was seen when enzyme activity was measured in vitro. Groups of mice were injected IM with 5 IU of either free or SHELS encapsulated L-asparaginase. In each case, half of the mice were passively immunized with rabbit polyclonal anti-asparaginase antibodies to a blood concentration of ∼0.5 mg/ml. Serum asparaginase levels pre and post injection were measured by HPLC at 2, 5 and 8 days. Both free and encapsulated enzyme produced complete depletion of asparagine at day 2, but by day 5 asparagine levels had returned to baseline in the animals given free enzyme, whereas those given encapsulated enzyme maintained depletion at day 5 with restoration to baseline at day 8. There was no asparagine depletion in immunized animals with the free L-asparaginase, but SHELS encapsulated asparaginase produced an identical depletion both in the presence or absence of the neutralizing antibodies, indicating that the SHELS effectively shield the enzyme from the antibodies. Experiments in tumor models are ongoing as well as dose response and repeated administration studies.

Disclosures:
No relevant conflicts of interest to declare.
Zebrafish Xenotransplantation and Focused Chemical Genomics: A Preclinical Therapeutic Model For T-Cell Acute Lymphoblastic Leukemia
Authors: Bentley Victoria L , Veinotte Chansey J , Corkery Dale , Leblanc Marissa A , Bedard Karen , Weng Andrew P , Dellaire Graham , Berman Jason N 
Published: October 2019

Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is a high-risk subset of ALL, for which there is a need for new therapeutic strategies and efficient preclinical screening methods. We have pioneered an innovative zebrafish human cancer xenotransplantation (XT) model to examine drug-tumor interactions in vivo. T-ALL cell lines and primary patient T-ALL samples were microinjected into 48-hour zebrafish embryos, a stage at which the adaptive immune system has not yet developed. Fluorescent labelling of tumor cells prior to injection and use of casper pigment mutant fish facilitates evaluation of drug response both by direct observation in transparent fish and enumeration of human cells following embryo dissociation. Proliferation rates are rapidly determined by directly counting fluorescent cells using in silico-based programs and/or utilizing immunohistochemical approaches to distinguish human cancer cells from host cell populations. T-ALL cell lines harboring defined mutations in the NOTCH1, phosphoinositide 3-kinase (PI3K)/AKT and mTOR pathways differentially responded to targeted inhibition using the γ-secretase inhibitor Compound E, triciribine, and rapamycin, when xenografted into embryos, consistent with responses in vitro. Primary patient-derived T-ALL bone marrow samples similarly engrafted and proliferated in zebrafish embryos. Using this in vivo chemical genomic approach, a targetable mutation sensitive to γ-secretase inhibition was identified from the diagnostic bone marrow sample of a child with T-ALL, which was confirmed by exome Sanger sequencing, and validated as a gain-of-function mutation in the NOTCH1 gene by luciferase assay and Western blot. Focused chemical genomics using the zebrafish T-ALL XT model provides a means of tailoring therapy using a real time in vivo assay that more accurately recapitulates the tumor microenvironment than in vitro methods and more rapidly than mouse xenografts. Moreover, the efficiency and cost-effectiveness of this innovative platform provides a novel intermediary for the prioritization of much-needed drug candidates in the preclinical pipeline.

Disclosures:
No relevant conflicts of interest to declare.
High-Dose Vincristine Sulfate Liposome Injection (Marqibo®) Is Not Associated With Clinically Meaningful Hematologic Toxicity
Authors: Deitcher Olivia R. , Glaspy John , Gonzalez Rene , Sato Takami , Bedikian Agop , Segarini Karen , Silverman Jeffrey A. , Deitcher Steven R. 
Published: October 2019

Abstract

Background
The treatment of hematologic malignancy patients with heavily pre-treated, advanced, relapsed, or refractory disease and those with advanced age, active infection, cardiovascular disease, recent surgery, or poor performance status may require therapies with limited hematologic toxicity and associated peripheral blood cytopenias. Cancer and concomitant chemotherapy related anemia, neutropenia, and thrombocytopenia in patients with hematologic malignancy complicate evaluation of hematologic toxicity related to new drugs. Vincristine sulfate liposome injection (VSLI; Marqibo®) is a new drug developed to optimize vincristine (VCR) pharmacokinetics and facilitate VCR dose-intensification and densification. VSLI is active in untreated and relapsed lymphomas, and was recently approved in the United States for relapsed and refractory adult Philadelphia chromosome-negative acute lymphoblastic leukemia.

Methods
We assessed the hematologic toxicity of VSLI 2.25 mg/m2 administered every 14 days (Cohort 1) or 7 days (Cohort 2) in 54 patients with metastatic uveal melanoma, a cancer not known to involve the bone marrow. Cohort 1 patients could have received 1 prior systemic therapy. Cohort 2 patients must not have received any prior systemic chemotherapy, immunotherapy, cancer vaccine, or hepatic arterial chemotherapy for metastatic disease.

Results
Patients in Cohort 2 received a higher median number of VSLI doses (6 vs. 4) over a shorter median time period (5.7 weeks vs. 8.7 weeks) resulting in a larger median cumulative exposure (22.6 mg vs. 17.7 mg) and near doubling of median dose density (4.0 mg/week vs. 2.2 mg/week) compared to patients in Cohort 1. Despite greater VSLI exposure and dose density, Cohort 2 had a smaller decrease from baseline in median neutrophil count and greater increase from baseline in median platelet count compared to Cohort 1. Both Cohorts experienced similar gradual decreases in hemoglobin concentration over time that were attributed to cancer-associated anemia and frequent blood sampling. Hematologic adverse events (AEs) were uncommon and mostly Grade 1 or 2. There were no Grade 4 hematologic AEs.

Conclusions
VSLI at its approved dose resulted in a low incidence of clinically meaningful hematologic toxicity. A near doubling of median dose density did not have an impact on the reported incidence and severity of hematologic AEs. VSLI may be well suited for use alone or in combination with myelosuppresive drugs and in patients unable to tolerate peripheral blood cytopenias.

Disclosures:
Silverman: Talon Therapeutics: Employment. Deitcher:Talon Therapeutics: Employment, Equity Ownership.
The Polymorphisms In LNK Gene Correlated To The Clinical Type Of Myeloproliferative Disorders
Authors: Chen Yan , Hu Yang , Wu Xueqiang , Fang Fang , Liu Qian , Zhang Ying , Zhu Ping 
Published: October 2019

Abstract

Objective
LNK (lymphocyte adaptor protein) is an adapter protein negatively regulating JAK/STAT cell signaling pathway. In this study, we observed the effects of variations in LNK gene on the clinical type of myeloproliferative disorders (MPD).

Methods
A total of 285 MPD cases were recruited, including essential thrombocythemia (ET) 154 cases, polycythemia vera (PV) 76 cases, idiopathic myelofibrosis (IMF) 19 cases, and chronic myeloid leukemia (CML) 36 cases. Ninety-three healthy individuals were used as normal controls. V617F mutation in JAK2 was searched by allele-specific primers method, RT-PCR was used for the detection of BCR/ABL1 fusion gene, and mutations and variations in exons and their flanking sequences of LNK gene were examined by PCR-sequencing. Count data were analyzed by χ2 or Fisher exact test.

Results
The genotypes of 4 SNPs (rs3184504, rs111340708, rs78894077and rs7973120) could be identified. Missense mutations of A300V, V402M, and R415H in LNK were found in 8 patients, of whom 3 ET patients had homozygous A300V mutation combined with JAK2V617F mutation. The genotypes and allele types of the 3 SNPs (rs3184504, rs111340708 and rs78894077) correlated to the clinical type of MPD. For rs3184504, the allele frequencies of C/T were 0.5/0.5 in normal controls, 0.117/0.883 in ET, 0.132/0.868 in PV, 0.211/0.789 in IMF, and 0.944/0.056 in CML; T allele (p.262Trp) was significantly higher in ET, IMF and PV (P<0.01), and C allele (p.262Arg) was significantly higher in CML (P<0.01), as compared with the controls. For rs78894077, the allele frequencies of C/T were 0.097/0.903 in normal controls, 0.045/0.955 in ET, 0.086/0.914 in PV, 0.053/0.947 in IMF, and 0.167/0.833 in CML; T allele (p.242Ser) was higher in ET (P<0.05) than in normal controls. For rs111340708 which has 2 alleles of repeated sequences (TGGGG x5/TGGGG x4), the allele frequencies of TGGGG x5/TGGGG x4 were 0.462/0.538 in normal controls, 0.719/0.281 in ET, 0.533/0.467 in PV, 0.789/0.211 in IMF, and 0.639/0.361 in CML; TGGGG x4 allele was significantly lower in ET, IMF and CML than in normal controls (P<0.01). However, the allele frequencies of rs3184504 and rs111340708 were unrelated to the presence of JAK2V617F mutation and BCR/ABL1 fusion gene in MPD patients.

Conclusion
The polymorphisms of SNPs in LNK gene correlated to the clinical type of MPD.

Disclosures:
No relevant conflicts of interest to declare.