bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of p53 Is a Marker of Progression in Plasma Cell Neoplasias and Is a Negative Prognostic Factor in Relapsed Disease.
Authors: Molnar Soledad , Zepeda Victor J Jimenez , Van Wier Scott , Braggio Esteban , Keats Jonathan , Kuehl Michael , Price-Troska Tammy , Ahmann Greg , Rempel Rachel , Henderson Kim , Rajkumar S. Vincent , Greipp Philip. R , Auclair Daniel , Carpten John , Baker Angela , Stewart Keith , Bergsagel P. Leif , Chng Wee Joo , Fonseca Rafael
Published: April 2020

Table 1. Samples to p53 deletions

p 53 deletion FISH aCGH FISH and aCGH MGUS 142 - - SMM 108 - - Newly diagnosed MM - 182 - Relapsed/refractory MM 62 156 19 HMCLs - 48 - Total 312 386 19

Background: Inactivation of p53 by mutation or allelic loss is a rare event in multiple myeloma (MM) at the time of disease diagnosis and believed to be more common in the late stages of the disease. Here we defined the prevalence of p53 deletions in monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), newly diagnosed MM, relapsed MM and human myeloma cell lines (HMCLs). Indirect mechanisms of p53 inactivation such as amplification of MDM2, or deletion of CDKN2A (p14ARF) were also investigated.

Patients and Methods: A total of 631 MM samples and 48 HMCLs were analyzed for p53 abnormalities (Table 1) and compared with a cohort of plasma cell leukemia (PCL) previously published by us. Interphase fluorescence in situ hybridization (FISH) and highresolution array-based comparative genomic hybridization (aCGH) were used to detect p53 deletions. MDM2 amplification and p14ARF loss were evaluated by aCGH. Overall survival (OS) was estimated through Kaplan Meier method.

Results: The prevalence of p53 deletions was 1.4%, 3.7%, 8.9%, 20% and 87.5% in MGUS, SMM, newly diagnosed MM, relapsed MM and HMCLs respectively (Figure 1). Of interest patients in first relapse showed a p53 deletion prevalence of 18% in comparison with 33% for patients in second relapse or more. We obtained p53 deletion status in 8 patients noted to have deletion at the time of relapse and in whom we had previous samples stored. In 7 of 8 cases deletions had been acquired (absent in the previous samples). The median OS for relapsed MM patients with or without p53 deletion were 4.2 months and 37.8 months respectively (p <0.001). MDM 2 amplification and p14ARF loss was detected in 0.4% and 2% of new diagnosed MM, 0.6% and 5.1% of relapsed MM and 2% and 29% of HMCLs respectively.

Discussion: Emergence of p53 deletion/mutations denotes progression genetic events in MM. Importantly we show for the first time the overriding importance of p53 deletions as prognostic markers in relapsed MM. A molecular staging system that is based on the presence of p53 inactivation may be more powerful than classifying patients based on the loss of p53. Other abnormalities involving p53 pathway regulators like MDM2 gain and p14ARF loss are infrequent events in MM, even in advanced disease.

Figure 1. Prevalence of p53 deletions Figure 1. Prevalence of p53 deletions
Clinical and Economic Outcomes Following Full or Partial ACCP Recommended Prophylaxis in Cancer Patients at Risk of Venous Thromboembolism
Authors: Amin Alpesh , Lin Jay , Yang Guiping , Stemkowski Steve
Published: April 2020

Background: As hospitalized cancer patients are at high risk of venous thromboembolism (VTE), evidence-based guidelines recommend VTE prophylaxis in this population. However, although VTE prophylaxis is frequently provided to at-risk medical and surgical cancer patients, it often fails to meet the criteria for best practice recommendations. As few data are available on the impact of inappropriate prophylaxis on clinical outcomes, we compare the safety and efficacy of fully appropriate or partially appropriate VTE prophylaxis in cancer patients using data from a large hospital administrative database.

Methods: Discharges from the Premier Perspective database (Jan 02–Dec 06) with a principal diagnosis of cancer, age ≥40 years, length of stay ≥6 days, and receiving some form of VTE prophylaxis, were included in the analysis. Discharges were excluded if they were transferred from another acute care facility or had any contraindications to VTE prophylaxis. Discharges were divided into two groups:

full prophylaxis, receiving ACCP-recommended prophylaxis for a sufficient duration (length of stay minus 2 days; minimum 3 days); partial prophylaxis, receiving some form of prophylaxis that was not recommended by the ACCP guidelines, or receiving a guideline-recommended prophylaxis type, but for an insufficient duration.

VTE, readmission, bleeding, mortality rates, and total hospital costs were collected and compared between groups using multivariate regression modelling.

Results: Among the 83,794 eligible discharges, the full prophylaxis group (n = 13,387, 16%) had a lower in-hospital VTE rate than the partial prophylaxis (n = 70,407, 84%) group (0.8% vs. 2.9%; odds ratio [OR] 3.09, 95% confidence intervals [CI] 2.51–3.80). Similarly, in-hospital mortality rates were lower in the full prophylaxis group (2.6% vs. 4.2%; OR 1.48, 95% CI 1.29–1.69). No major bleeding events were observed in either group, potentially due to the miscoding of these events. The mean total hospital cost was higher for patients receiving partial prophylaxis ($17,128) than full prophylaxis ($15,284).

Conclusion: US cancer patients receiving partial prophylaxis have a higher risk of VTE and mortality than patients receiving full guideline-recommended prophylaxis, leading to a higher total hospital cost. It is important that individual hospitals improve the use of full prophylaxis to reduce both the clinical and economic burden posed by VTE.

Disclosures: Amin: sanofi-aventis: Consultancy, Financial and editorial support for this publication was provided by sanofi-aventis US, Inc., Honoraria. Lin:sanofi-aventis: Employment. Yang:sanofi-aventis: employee of Premier Inc which has received funding to perform this research from sanofi-aventis. Stemkowski:sanofi-aventis: employee of Premier Inc which has received funding to perform this research from sanofi-aventis.
Gamma-Globin Gene Expression in Adult Human Erythroblasts Is Associated with Concurrent Changes in the Nuclear Protein Levels of at Least Seven Transcription Factors.
Authors: Sripichai Orapan , Lee Y. Terry , Tanno Toshihiko , Noh Seung-Jae , Byrnes Colleen , Meier Emily Riehm , Miller Jeffery L
Published: April 2020

Alterations of globin-gene cluster expression mediated through cytokine signal transduction have been previously established. In adult erythroblasts, ex vivo combinatorial signaling from cytokines such as erythropoietin (EPO), stem cell factor (SCF), and transforming growth factor-beta (TGF-B) causes a robust reactivation of fetal hemoglobin. To determine if cytokine-activated expression of fetal hemoglobin significantly alters the transcript and protein abundance of nuclear transcription factors, profiling studies of transcription factor expression were performed. Primary CD34+ cells were cultured as donor-matched pairs using cytokine combinations that produced low vs. high levels of gamma-globin mRNA and fetal hemoglobin (Bhanu et al. Blood, 2005). To identify candidate genes, total RNA from 15 separate healthy volunteer donors was collected and combined into 5 pools. The pooled RNA was labeled and hybridized to Affymetrix HG-U133 Plus 2.0 GeneChips. Informatics strategies were aimed toward identifying differential expression of those transcription factors with binding motif on any of the 10 human globin gene promoter regions (553 transcription factors; 115 binding motif families), versus all transcription factors demonstrating robust expression with changes of at least 3-fold. Combining both strategies, 11 candidate transcription factors were identified (BCL11A, CBFB, EGR-1, ELK-1, HHEX, ID2, MAFF, MNDA, SOX-6, TCF3, and THRB). RNA-based descriptions of gene activity do not necessarily reflect changes in protein levels; therefore, Western analyses were performed. GATA-1 was utilized as a control, since no significant change in GATA-1 mRNA was detected by expression array profiling. Nuclear protein extracts were obtained from 3 additional donors’ CD34+ cells cultured under conditions of low vs. high gamma-globin mRNA synthesis (1.6E+06 ± 3.8E+05 and 1.5E+07 ± 6.3E+06 copies/ng total RNA, respectively). Western blot analysis revealed reproducible and robust differences in protein expression levels for 7 of the 11 candidate transcription factors (EGR-1, ELK-1, HHEX, ID2, MAFF, MNDA, and SOX-6). Two other candidates were expressed below the protein detection limit. GATA-1 and the remaining 2 candidates demonstrated no change in the nuclear protein levels. Among the group with confirmed changes in gene expression, ELK-1 and EGR-1 are downstream targets of the MAP kinase signal transduction cascade. MAFF, ID2, and SOX-6 are known regulators of globin gene expression. The differential expression of HHEX and MNDA warrants further investigation. These data demonstrate that cytokine signal transduction causes changes in the intranuclear levels of at least 7 transcription factors concurrently with activation of gamma-globin gene expression.
Placenta Endothelial Protein 1 Is a Novel Neural Guidance Molecule on Angiogenesis.
Authors: Wang Chieh-Huei , Lin Chia-Yi , Yang Chung-Chi , Chuang Yung- Jen
Published: April 2020

Angiogenic Processes are tightly regulated by guidance molecules for directed blood vessel growth during development and under diseased conditions. Here we report a novel protein, Placenta Endothelial Protein-1 (PEP1), which may participate in the neurovascular interaction and vessel guidance. Identified by SAGE database mining, PEP1 is highly expressed in human placenta vasculatures and is well-conserved among all vertebrates. In silico analysis predicted the potential roles of PEP1 may involve in the cell migration and cell-to-ECM interaction. To investigate the function of PEP1, we altered endogenous PEP1 expression in human umbilical vein endothelial cells (HUVECs) for subsequent angiogenesis assays. Our data indicated overexpression of PEP1 in HUVEC significantly decreased cell motility and tubular formation capability, whereas knockdown of PEP1 in HUVECs resulted in the opposing effects. To characterize PEP1 in vivo, we next examined the physiological roles of zPEP1 (PEP1 ortholog in zebrafish) during zebrafish embryonic development. Real-time quantitative PCR analysis first indicated zPEP1 to express after 16 hours post-fertilization (hpf), which coincides with the start of vascular development. To our surprise, whole mount in situ hybridization showed that zPEP1 was expressed prominently in the neural stem cells of developing nervous system, suggesting PEP1 may function as a neural guidance molecule. By injecting morpholino antisense oligos to knockdown zPEP1 expression in developing embryos, we observed stalled growth of intersegmental vessels, reaffirming the role of PEP1 in regulating angiogenesis. Besides, confocal immunocytochemistry analysis shown a co-localization of PEP1 and paxillin in HUVEC, implying the regulatory effect of PEP1 may enact via the paxillin-dependent signal pathway. Taken together, our study revealed the significant roles of PEP1 in neurovascular interaction and vascular patterning. Future analysis on this novel vessel patterning protein shall shed light on the complex communication network between nervous and vascular systems.
Cell-Driven Angiogenesis and Neurogenesis after Stroke Is Regulated by Platelet’s Microparticles.
Authors: Varon David , Haion Yael , Brill Alexander , Leker Ronen
Published: April 2020

Repair mechanisms based on the proliferation of endogenous cells have been identified in ischemic brain regions suggesting that precursors at the ventricular surface proliferate, migrate to sites of injury and differentiate into neurons. However, this response is significantly limited by short survival times and poor differentiation capacity of these cells. External factors can boost endogenous neural stem cells (eNSC)-dependent repair mechanisms in the cerebral cortex. Upon activation, platelets shed platelet derived microparticles (PMP) which contain a variety of growth factors central to angiogenesis and neurogenesis. We have previously reported a pro angiogenic effect of PMPs, both in vitro and in vivo. We thus hypothesized that the functional benefits obtained from the presence of newborn cells can be further enhanced by increasing the survival rates, migration and differentiation potential of these cells, as well as by promoting angiogenic response, applying PMPs at the site of a stroke. Spontaneously hypertensive rats underwent permanent middle cerebral artery occlusion (PMCAO) and were given BrdU to label newborn cells. Animals were treated with vehicle or PMP delivered via a biodegradable polymer applied to the brain surface. Rats were tested with a neurological severity score and infarct volumes were measured at 90 days post –PMCAO. We used immunohistochemistry to determine the fate of newborn cells and to count blood vessels in the ischemic brain. The results show that PMP treatment led to a dose dependent increase in neurogenesis and angiogenesis at the infarct boundary zone. PMP also significantly improved behavioral deficits without affecting infarct volumes.
Rearranged Infant Acute Lymphoblastic Leukemia.
Authors: Stam Ronald W. , Den Boer Monique L. , Schneider Pauline , de Boer Jasper , Hagelstein Jill , Sallan Stephen E. , Brady Hugh J.M. , Armstrong Scott , Pieters Rob
Published: April 2020

MLL rearranged Acute Lymphoblastic Leukemia (ALL) represents an unfavorable and difficult to treat type of leukemia that often is highly resistant to glucocorticoids like prednisone and dexamethasone. As the response to prednisone largely determines the clinical outcome of pediatric ALL patients, overcoming resistance to these drugs may be an important step towards improved prognosis. Here we compared gene expression profiles between prednisone-resistant and prednisone-sensitive pediatric ALL patients to obtain gene expression signatures associated with prednisone resistance for both childhood (>1 year of age) and MLL rearranged infant (<1 year of age) ALL. Merging both signatures in search for overlapping genes associated with prednisone resistance in both patient groups we, found that elevated expression of MCL-1 (an anti-apoptotic member of the BCL-2 protein family) appeared to be characteristic for both prednisone-resistant ALL samples. To validate this observation, we determined MCL-1 expression using quantitative RT-PCR in a cohort of MLL rearranged infant ALL samples (n=23), and confirm that high-level MCL-1 expression significantly confers glucocorticoid resistance both in vitro and in vivo. Finally, down-regulation of MCL-1 in prednisone resistant MLL rearranged ALL cells by RNA interference (RNAi) markedly sensitized these cells to prednisone. Therefore we conclude that MCL-1 plays an important role in glucocorticoid resistance and that MCL- 1 suppressing agents co-administered during glucocorticoid treatment may be beneficial especially for MLL rearranged infant ALL patients.
Tubacin, An Inhibitor of HDAC6, Induces Apoptosis of Acute Lymphoblastic Leukemia Cells in Vitro and in Vivo through a Na+/K+ATPase-Dependent Pathway.
Authors: Rodriguez-Gonzalez Agustin , Simms-Waldrip Tiffany , Ikeda Alan K. , Lin Tara , Lomenick Brett , Aldana-Masangkay Grace , Mazitschek Ralph , Bradner James , Fu Cecilia , Sakamoto Kathleen M.
Published: April 2020

Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer. Despite effective chemotherapy, 25 to 30% of children will relapse. In adults, less than 30% of patients with ALL are cured. Therefore, it is critical that we identify novel therapies to treat ALL. We are studying the effects of a small molecule compound known as tubacin (tubulin acetylation inducer) that selectively inhibits histone deacetylase 6 (HDAC6) resulting in increased acetylation of alpha-tubulin by inhibiting one of the two catalytic domains of HDAC6. We found that treatment of both pre-B and T-ALL cell lines with tubacin inhibits growth at very low micromolar concentrations (Jurkat IC50=1μM, Loucy IC50=3μM, REH IC50=2μM, Nalm6 IC50=5μM). We also determined that there is a therapeutic window, since tubacin inhibits the growth of normal bone marrow progenitor cells in methylcellulose colony assays at 20μM and normal human lymphocytes cultured in IL-2 at an IC50 of 16μM. We next tested the effects of tubacin in vivo. SCID mice injected with pre-B ALL Nalm-6 cells were treated with tubacin intraperitoneally at 50 mg/kg/day. Preliminary data using bioluminescence imaging in SCID mouse models showed that tubacin inhibited leukemic progression in vivo. To understand the mechanism of tubacin in ALL cells, we examined both apoptosis and cell cycle regulation by PARP cleavage, activation of caspases, and propidium iodide staining with FACs analysis. Tubacin induced apoptosis of pre-B and T-ALL cells within 12 hours of treatment. There was no effect on cell cycle progression, Retinoblastoma protein phosphorylation, or p21 upregulation, which have been observed with other HDAC inhibitors. Unlike in myeloma cells, tubacin did not increase JunK/SAPK activation or accumulation of acetylated HSP90 in ALL cells. Tubacin treatment resulted in accumulation of acetylated alpha-tubulin after 1 hour and an increase in polyubiquitinated proteins after 7 hours. To address potential mechanisms of tubacin in ALL, we tested whether Na+/K+ ATPase could be contributing to apoptosis. Previous work has shown that treatment with L-glutamate dissociates the Na+/K+ ATPase complex from acetylated tubulin and restores ATPase enzymatic activity. We hypothesized that the accumulation of acetylated tubulin could potentially inhibit the activity of the cytosolic Na/K ATPase pump, which could be reversed by treatment with 1mM sodium glutamate. Preliminary data demonstrate that we can partially rescue the effects of tubacin on PARP cleavage with sodium glutamate. These results suggest that tubacin induces apoptosis through a novel pathway in ALL cells and provide rationale for targeting the aggresome pathway to treat ALL in the future.
Acute Lymphoblastic Leukemia (ALL) or Lymphoblastic Lymphoma (LL) after Frontline Therapy with Hyper-CVAD Regimens.
Authors: Thomas Deborah A. , O’Brien Susan , Rytting Michael , Faderl Stefan , Cortes Jorge , Wierda William G. , Ravandi Farhad , Kantarjian Hagop M
Published: April 2020

AYAs aged 16–20 with de novo ALL or LL have superior outcomes when treated with intensive pediatric regimens; event-free survival (EFS) rates range from 60–70% compared to 30–40% after conventional adult chemotherapy [Stock W, Blood 2008, e-pub]. This is in part attributed to higher dose intensity (and cumulative dose) of the anthracycline, vincristine [VCR], corticosteroid and asparaginase components. Of note, the intensive hyper-CVAD regimen (cyclophosphamide, VCR, doxorubicin, dexamethasone alternating with methotrexate/cytarabine) was originally modeled after childhood therapy for Burkitt lymphoma. It has been applied as frontline adult ALL therapy without age restriction since 1992. In contrast to conventional adult or pediatric ALL regimens, asparaginase is not administered during the induction or consolidation phases. Modifications to the regimen have included the addition of rituximab for CD20 positive precursor B-cell ALL and LL owing to adverse influence of CD20 expression, particularly in the younger subgroup [Thomas D, Blood 2008, e-pub]. An adapted augmented Berlin-Frankfurt- Munster (BFM) regimen modeled after the CCG experience was developed specifically as frontline therapy for adolescents and adults up to age 30 in lieu of the hyper-CVAD regimen at our institution; accrual is ongoing. We reviewed the previous hyper-CVAD experience in the AYA subset. One hundred two pts aged 13 to 21 yrs (median 19 yrs) with de novo ALL (n=92) or LL (n=10) were treated with hyper-CVAD (15 with rituximab). Complete remission (CR) rate was 97%; 3-yr EFS and OS rates were 65% and 70%, respectively. Preliminary reports from other investigators suggest that an intensified pediatric approach may be feasible even up to age 60. The GRAALL-2003 study reported 42-mos EFS and OS rates of 55% and 58%, respectively, in 225 de novo ALL pts aged 15– 60 (median 31 yrs) [Huget F, ASCO 2008, abstr 7005]. Median follow-up was 37 mos. A similar cohort of pts treated with the hyper-CVAD regimens included 385 pts with a slightly older median age of 35 yrs. Median follow-up was 62 mos (range, 1–180 mos). EFS and OS rates for the entire cohort were 50% and 55%, respectively. For pts below the age of 35, these rates improved to 55% and 67%. Clearly age remains a prognostic factor even with intensive chemotherapy approaches. Outcomes with the hyper-CVAD regimens appear to more closely resemble those of the pediatric approaches than the conventional regimens. Continued monitoring of ongoing prospective clinical trials using pediatric regimens in adults is paramount to delineating the optimal approach.
High Dose Cytarabine and Clofarabine (HiDAC → CLOF) in Relapsed or Refractory Acute Myeloid Leukemia, a Phase 2 Trial.
Authors: Powell Bayard , D’Agostino Ralph , Levitan Denise , Ellis Leslie Renee , Lyerly Susan , Skiles Megan , Manuel Megan , Harrelson Robin , Kimbrough Claire , Hurd David Duane
Published: April 2020

High dose cytarabine (HiDAC) is the most effective single agent studied to date for the treatment of acute myeloid leukemia (AML); clofarabine (CLOF) is also an active single agent in AML. Preclinical data suggest synergy between cytarabine and clofarabine. Based on the results of a limited phase 1 trial (Blood2006; 108: 221b), we conducted a phase 2 study of HiDAC (2g/m2 over 3 hours) followed immediately by CLOF (40 mg/m2 infused over 2 hours), given daily for 5 days, in 39 adults with AML in first relapse (n = 27), second relapse (n = 3), or refractory to initial induction chemotherapy (n = 9). Prophylactic intravenous hydrocortisone was incorporated to decrease the occurrence of skin toxicity. Patients with persistent leukemia on day 12–14 (n = 12) received a second course of HiDAC → CLOF for 3 days. The mean age was 53.4 years (range 18.4 – 79.0). Accrual began March 2006 and was completed in July 2008. Thirtyseven of 39 patients are evaluable for response (two patients were treated recently and are not included in this analysis): 14/37 achieved a complete remission (CR), 2/37 a CR with incomplete blood count recovery (CRi) for an overall response (CR or CRi) in 16/37 (43%; 95% CI 27 – 59%). Twelve of 37 (32%) patients had resistant disease, 3/37 (8%) died of complications during marrow aplasia, 5/37 (14%) died of complications of their AML with unknown bone marrow status, and 1/37 (3%) refused further evaluation or treatment. CR or CRi was achieved in 11/25 patients in first relapse, 2/3 in second relapse, and 3/9 with refractory AML. Twelve patients received a second induction – 2/12 (17%) achieved a CR and 1/12 (8%) a CRi. Toxicity data are complete in 36 patients; the most frequent grade 3/4 non-hematologic toxicities were transient elevations of AST/ALT observed in 23/36 (64%) patients, hyperbilirubinemia in 8/36 (22%), infection in 16/36 (44%), and rash in 8/36 (22%). Patients who achieved CR or CRi received up to 3 additional courses of HiDAC → CLOF each daily for 5 days. Twenty-seven of 39 (69%) patients have died with a median survival of 119 days (95% CI 71 – 322 days). In summary, HiDAC → CLOF is a very active combination in adults with relapsed and refractory AML, a group in whom CR/CRi rates of 30–35% are achieved with many salvage regimens. Toxicities are comparable to other salvage regimens with transient elevations in transaminases identified as the most frequent toxicity.
Mobilization and Chemosensitization of AML with the CXCR4 Antagonist Plerixafor (AMD3100): A Phase I/II Study of AMD3100+MEC in Patients with Relapsed or Refractory Disease.
Authors: Uy Geoffrey L. , Rettig Michael P. , McFarland Kyle M. , Hladnik Lindsay M. , Kulkarni Shashikant , Abboud Camille N. , Cashen Amanda F. , Stockerl-Goldstein Keith , Vij Ravi , Westervelt Peter , DiPersio John F.
Published: April 2020

The interaction of leukemic blasts with the bone marrow microenvironment is postulated to be an important mediator of chemoresistance in AML. Although a number of receptor/ligand pairs have been implicated, the CXCR4/SDF-1 axis functions as the principal regulator of homing and retention of both normal and malignant hematopoietic cells in the marrow. Plerixafor (AMD3100) is a bicyclam molecule which reversibly blocks CXCR4 binding to SDF-1 and is being developed clinically as a mobilization agent for hematopoietic stem cell transplantation. Preclinical data from our group has demonstrated that in murine models, plerixafor can disrupt the interaction of leukemic cells with the marrow microenvironment and sensitize blasts to the effect of chemotherapy. Based on these data, we have initiated a phase I/II study in patients with relapsed or refractory AML in which plerixafor is administered prior to salvage chemotherapy. Subjects were required to have AML which is

primary refractory to at least 2 induction regimens, in 1st relapse with an initial remission duration of < 12 months, in 1st relapse having failed ≥ 1 salvage regimens, or in 2nd relapse or higher. Plerixafor is administered by SQ injection followed by a 24 hour observation period to analyze its effects on leukemic cell mobilization.

Then plerixafor is given daily 4 hours prior to chemotherapy consisting of mitoxantrone 8mg/m2/d, etoposide 100 mg/m2/d and cytarabine 1000 mg/m2/d x 5 days. To date, 19 patients have been treated at 3 dose levels of plerixafor: 80, 160 and 240 mcg/kg/day. We find that plerixafor can modestly mobilize leukemic cells (~ 2-fold increase) into the peripheral circulation at a peak of 6–8 hours after administration. FISH studies performed from informative samples demonstrates that this mobilization occurs equally in both non-leukemic and leukemic populations. While CXCR4 expression is increased on the surface of mobilized blasts, no clear relationship has been observed between CXCR4 expression or plerixafor dose and mobilization. At the 80 and 160 mcg/kg dose levels, a complete response (CR+CRi) was observed in 2 of 6 patients (33%). At the plerixafor 240 mcg/kg dose level, a complete response (CR+CRi) was achieved in 6 of 8 evaluable patients (75%) in this historically chemorefractory population. Plerixafor was well tolerated with no evidence of hyperleukocytosis or significant delays in neutrophil recovery (median 30 days, range 24–40). Based on this encouraging evidence of safety and efficacy, expansion of a phase II cohort is ongoing.
A Homoharringtonine-Based Protocol Is Superior to Daunorubicin and Idarubicin-Based Protocols in Elderly Patients with Newly-Diagnosed Acute Myeloid Leukemia with Comparable Effects and Low Toxicities: Experience in a Chinese Center.
Authors: Wang Jianmin , Lü Shuqing , Yang Jianmin , Song Xianmin , Chen Li , Hou Jun , Zhang Weiping , Huan Chongmei , Ni Xiong , Qiu Huiying
Published: April 2020

Homoharringtonine (HHT) is a plant alkaloid which has been used in China for the treatment of acute myeloid leukemia (AML) and chronic myeloid leukemia for over 30 years. We present here a retrospective analysis designed to compare the efficacy and toxicity of HHT with daunorubicin (DNR) and idarubicin for the treatment of AML in elderly patients. Fifty-three patients over 60 years with newly diagnosed non-M3 AML between January 1998 and December 2007 were treated with cytarabine (Ara-c, 100mg/m2/day for 7 days) in combination with HHT (2mg/m2/day for 7 days; HA group; n=19), or DNR (40mg/m2/d for 3 days; DA group; n=16), or idarubicin (8mg/m2/d for 3 days; IDA group; n=18). In the HA group, 42.1% (8/19) of patients achieved complete remission (CR), 26.3% (5/19) of patients had partial remission (PR). In the DA group, the CR and PR rates were each 18.8% (3/16). In the IDA group, 55.5% (10/18) of patients achieved CR, 5.9% (1/18) patients had PR. The CR and OR rates were not significantly different between the three groups. However, whereas in the IDA and DA groups the early death rate within one month after chemotherapy was 33.3% (6/18) and 23.5% (4/16) respectively, there was no early death in the HA group. The estimated OS (overall survival) times were 23.2±7.9 months, 7.6 ±2.1 months, 14.0±3.4 months in HA, DA, and IDA groups (HA versus DA, P = 0.048; HA versus IDA, P = 0.678). The estimated mean disease-free survival (DFS) time of those patients who achieved CR in the HA group (44.3±17.3) were also significantly higher than those in the DA group (7.8±2.7; P = 0.047), and comparable with those in the IDA group (18.0±4.2; P = 0.598). In summary, the response to HA induction therapy was at least equal to that of DA and IDA induction, with relatively mild extramedullary toxicity and lower myocardial toxicity. So HHT is a particularly suitable candidate for the treatment of elderly AML patients.
Pharmacokinetics, Clinical Efficacy and Safety of Plasma-Derived Nanofiltered C1 Inhibitor Concentrate for Treatment of Hereditary and Acquired Angioedema.
Authors: Hofstra J. J. , van Twuyver E. , Kleine-Budde I. , Choi C. W. , Levi M. , Leebeek F. W.G. , de Monchy J. G.R. , Ypma P. F. , Huitema A. D. , Nienhuis A. , Strengers P. F.
Published: April 2020

RATIONALE: From the early 70’s, C1 inhibitor concentrate manufactured from pooled human plasma has been available to patients with hereditary and acquired angioedema (HAE and AAE) and in 1997 a highly purified C1 inhibitor (Cetor®) was introduced. Many precautions have been taken to minimize the potential risk of viral transmission (e.g. rigorously controlled whole blood collection systems, extensive screening of each individual donation for a variety of blood-borne viruses, pasteurisation). To further minimize the potential risk of viral transmission, a 15 nm filtration was implemented in the manufacturing process giving rise to C1-inhibitor-N (anofiltered).

DESIGN: A randomised, double-blind, controlled cross-over phase II study was conducted in which our primary objective was to compare the pharmacokinetics of the newly developed concentrate with conventional C1-inhibitor concentrate in HAE patients without signs of an attack of angioedema. Secondly, an open-label phase III study in patients with an HAE attack was performed to investigate whether the introduction of the virus reducing 15nm filtration step in the manufacturing process of the concentrate did not affect the efficacy and safety of the product.

RESULTS: Thirteen patients were enrolled in the phase II study. No differences between conventional C1-inhibitor concentrate and nanofiltered C1-inhibitor concentrate were detected with regard to the primary pharmacokinetic parameters clearance, volume of distribution, and the fraction of C1-inhibitor-N detected by the antigen assay relative to the functional assay. Therefore incremental recovery, mean residence time, half-life and the area under curve were equivalent for both products. In the phase III study, 8 HAE patients were enrolled. In these 8 patients, 14 attacks qualified as acute angioedema attack. The mean time-to-relief for attacks treated with new C1-inhibitor concentrate was 3.0 (SD 2.5) hours. Historical data showed that treatment with conventional C1-inhibitor concentrate resulted in time-to-relief of 3.9 (SD 6.2) hours, whereas for untreated attacks this was 24.7 (SD 19.9) hours. The attacks treated with new C1-esterase inhibitor concentrate had a mean time-to-resolve of 18.6 hours (SD 13.1) whereas medical history showed an time-to-resolve of 17.8 hours (SD 17.2) for conventional C1-inhibitor. Untreated attacks showed a mean time-to-resolve of 63.6 hours (SD 31.0).

CONCLUSION: The newly developed nanofiltered C1-esterase inhibitor has equal pharmacokinetic properties compared to the conventional concentrate. The viral reduction step (15 nm filtration) in the production process of Cetor did not induce changes in the efficacy and safety in the treatment of acute angioedema attacks and in the pharmacokinetic parameters.
Safety in Patients Receiving Maintenance Rituximab for Follicular Lymphoma: Results from Phase IIIb MAXIMA Trial.
Authors: Witzens-Harig Mathias , Hipp Joachim , Ho Anthony D. , Nikolov Nikolai , Thurley Daniel , Hensel Manfred , Oertel Stefan , Wenger Michael
Published: April 2020

Background: The clinical benefit of improved PFS and OS for rituximab maintenance in follicular lymphoma (FL) has been reported in five randomized trials. The primary objective of the current study is to extend the safety database for rituximab maintenance following a wide range of induction therapies. The study also examines the safety profile associated with rapid-infusion of rituximab.

Methods: The sample size of this single-arm trial has been calculated to detect at least one rare event with a true incidence of 0.32% with 80% power. Patients with first line or relapsed/refractory FL achieving a response after rituximab containing induction therapy were eligible to receive rituximab at the standard dose for follicular lymphoma of 375 mg/m2 every eight weeks for a maximum of 2 years. Primary study endpoint is safety. Secondary endpoints being PFS, EFS, TTNL, and OS.

Results: 526 patients with FL have been enrolled at clinical cut-off for whom demographic data is available: Median age of the patient population is 57 years [range: 29 to 86], with 43% being male. Seventy-four percent of patients had their first lymphoma treatment prior to enrollment, while the remaining 24% of patients had up to 4 previous treatments; 71% entered the study in CR/CRu. Data on a total of 2004 infusions was available. Except for one patient who received rituximab at standard infusion speed and suffered from a TIA no SAEs were recorded within 24h of the maintenance infusion, including those patients who received rituximab via a rapid infusion protocol. A total of 31 SAEs were recorded in the 484 patients that received at least one infusion, all but one were considered unrelated. One patient with previously known cardiac arrythmias died 13 days after the 4th infusion of unknown causes. Three patients died of progressive lymphoma, another patient died due to refractory ITP. Hematologic toxicity occured in 13 patients, with one grade 5 event (ITP) and 12 grade 3/4 events, one resulting in febrile neutropenia. Data on efficicacy will be presented.

Conclusions: Rituximab maintenance q 8 weeks in FL after rituximab containing induction therapy can be safely administered, regardless if a rapid-infusion protocol is used or not.
Extended Follow-up of the International Randomized Phase 3 First-Line Indolent Trial (FIT) Shows Durable Benefit of 90 Y-Ibritumomab Tiuxetan (Zevalin®) Consolidation of First Remission in Advanced Stage Follicular Non-Hodgkin’s Lymphoma.
Authors: Morschhauser Franck , Bischof-Delaloye Angelika , Rohatiner Ama Z S , Salles Gilles Andre , Kuhlmann Jens , Van Putten Willem JL , Radford John , Soubeyran Pierre , Van Hoof Achiel , Hagenbeek Anton
Published: April 2020

Initial findings from the Phase 3 trial of Zevalin consolidation of first remission in patients with advanced follicular lymphoma showed a significant improvement in PFS following Zevalin consolidation as compared to no further treatment, ie, 37.5 vs. 13 months (Hagenbeek et al, ASH 2007). Patients had been randomised to either no further therapy or Zevalin consolidation (250 mg/m2 rituximab on day -7 and on day 0, followed on day 0 by Zevalin 0.4 mCi/kg; maximal dose 32 mCi). Herein we report on an additional 1-year follow-up of the FIT study, at a median of 42 months (range: 2 – 77), which includes 409 patients who achieved a complete or partial response (CR or PR), after induction therapy. Patient demographics remain similar in the Zevalin (n=202) and control groups (n= 207): males 48%/50%; median age 55/53 yrs; at diagnosis, stage III 35.2%/31%, stage IV 64%/66%. Response status prior to randomization was also similar between study arms: 107 patients in CR/CRu and 100 pts in PR in the Zevalin arm and 108 pts in CR and 88 pts in PR in the control arm. The 48-month PFS is 52% in the Zevalin arm compared with 31% in the control arm. As shown in the figure 1A, patients with a CR after induction therapy achieved a median PFS of >67 months for the Zevalin arm compared with 30.8 months for patients who received no further treatment (HR 0.61 [95% CI .41–.91]; P= 0.015). In figure 1B, among patients with a PR after induction, the median PFS was 29.6 months for those on the Zevalin arm vs 6.7 months for those on the control arm (HR 0.36 [95% CI .25–.51]; P<0.001). Subsequent therapy with various modalities including chemotherapy, radiotherapy, immunotherapy, Zevalin and stem cell transplantation (ASCT) was given to 63 patients in the Zevalin arm and 108 patients in the control arm, who achieved an overall response rate of 81% and 73%, respectively. A total of 11 deaths have occurred in the Zevalin arm and 8 in the control arm, with no difference in overall survival between the treatment arms (P=0.593). No additional toxicities, no congenital malformations, and no increase in the incidence of secondary malignancies have emerged during follow-up. Details on subsequent therapies and a breakdown of outcomes based on induction subgroups and FLIPI scores are anticipated for presentation.

Conclusion: Extended follow-up of the FIT trial shows that Zevalin consolidation does not preclude the use of various effective second-line treatment options. Moreover, these data confirm that the significant improvement in PFS achieved with Zevalin consolidation is durable for both patients with a PR and patients with a CR/CRu after induction.

Figure Figure
Age-Related Differences in the Glycosylation of Anticoagulant Protein C.
Authors: Berry Leslie R. , Chan Anthony K. C.
Published: April 2020

Thromboembolic events can result from procoagulant stimuli and the inability of native anticoagulant mechanisms to pacify thrombin generation. In the pediatric population, although thrombosis occurs in the presence of major coagulant insults, children are relatively resistant to onset of thrombotic complications. A key aspect contributing to developmental differences in the young is that coagulation factors and inhibitors have been shown to exist in different plasma concentrations and developmental forms compared to adults. Increasing evidence indicates that protein C (PC) is a major factor that, upon activation, controls coagulation by shutting down thrombin generation. In adults, PC exists as either 4 N-linked glycan (alpha-PC) or 3 N-linked glycan (beta- PC) proteins that differ in the rate at which their corresponding activated forms react with coagulation factor Va. Our previous work has shown that although plasma PC concentrations are vastly reduced in newborn plasma, inactivation of factor Va is similar to adults, suggesting a potential difference in PC molecules during development. To assess the potential for age-related PC molecule variation, we performed carbohydrate analyses to determine the relative glycoform composition of PC in newborns compared to adults. Venous plasma from either adults or umbilical cords of healthy full-term babies was collected following the ethical guidelines of our institution. Samples of plasma were run on non-reducing SDS polyacrylamide gel (7.5%) electrophoresis, followed by transfer onto PVDF blotting membranes. Blots were probed with polyclonal sheep anti-human PC, followed by anti-sheep IgG-alkaline phosphatase conjugate and then alkaline phosphatase substrate to visualize the protein bands. Relative intensity of alpha-PC and beta-PC bands was determined by laser densitometry. Analyses revealed that significant age differences existed in PC glycoform composition between adults and newborns. While the mass ratio of alpha-PC to the lower molecular weight band of beta PC was 2.3 to 1 for the adult plasma protein, newborns were observed to have an alpha-PC to beta-PC ratio of 8.8 to 1. Thus, an almost 4-fold increase in the circulating alpha-PC to beta-PC ratio was observed in newborns compared to adults. As a confirmation that the difference in migration between the alpha-PC and beta-PC bands was due to glycosylation, removal of N-glycans by treatment of newborn and adult plasma with N-glycosidase F prior to electrophoresis resulted in single bands that now migrated at the same rate for both age groups. We have demonstrated that relative expression of the 2 major PC glycoforms varies widely during development. Given that alpha-PC in its activated form has a much faster rate for factor Va inactivation compared to beta-PC, its increased appearance in newborn plasma may play a role in protecting neonates from thrombosis, despite reduced plasma inhibitor concentrations.
T Cells from Patients with Chronic Lymphocytic Leukaemia Prevent Apoptosis of Autologous CLL Cells in a Dose- and Cell:Cell-Contact Dependent Fashion; Rationale for New Therapeutic Possibilities.
Authors: Rossmann Eva , Kokhaei Parviz , Mozaffari Fariba , Palma Marzia , Osterborg Anders , Mellstedt Hakan , Choudhury A. Raja
Published: April 2020

Background: Multiple T cell abnormalities in Chronic Lymphocytic Leukemia (CLL) patients are well established. Compared to healthy individuals, total T lymphocyte count, CD8+ cells and CD4+ cells in CLL patients are increased and follow disease activity, i.e. increase at CLL progression. Major alterations in T cell functions and TCR repertoire have also been reported as well as T cells specifically recognizing the leukemic CLL cells. It may be hypothesized that aberrantly functioning T cells contribute to a microenvironment which may allow CLL cells to avoid apoptosis and/or support the proliferative capacity. However, the underlying mechanisms are largely unknown.

Materials and Methods: T cells and CLL cells were highly purified from PBMC of 20 patients with indolent CLL as well as normal blood B- and T-cells from healthy control donors (n=7). Autologous T cells and B cells were co-cultured at different T:B ratios for 72 h in ordinary and transwell plates. Apoptosis of B cells were assayed using Annexin-V and supernatants were analysed by Luminex for the following cytokines: RANTES, IL-10, IL-8, TNF-α, IFN-γ, IL-4, MCP-1, CD40L and GM-CSF.

Results: Apoptosis of CLL cells was significantly (p<0.01) prevented by autologous T cells in a cell-dose-dependent fashion; the highest rate of apoptosis was observed when CLL cells were cultured alone in the absence of T cells. When the experiments were repeated in transwell plates the apoptosis-inhibiting effect of the T cells was completely ameliorated. No corresponding effects were observed when T cells were co-cultured with normal B cells of healthy donors. Luminex analysis revealed that the levels of IL-4, RANTES, MCP-1, TNF-α and IFN-γ were significantly higher in CLL co-culture experiments (especially at high T:B ratios) as compared to CLL cells alone.

Conclusions: Our data provide proof-of-principle that autologous T cells prevent apoptosis of CLL cells in a dose-dependent fashion and the effect was critically dependent on cell:cell contact. A number of cytokine candidates were identified for further studies. The results provide a basis for exploring therapeutic approaches aiming at selective inhibition/depletion of T cells in patients with CLL.
Platinum-Based Compounds Induce Expression of p73 and Restores Drug- Sensitivity in p53 Dysfunctional Chronic Lymphocytic Leukemia (CLL) Cells.
Authors: Tonino Sanne H. , Mulkens Chantal , Nonomura Yoshinori , Suo Guangli , Kipps Thomas J. , van Oers Marinus H.J. , Eldering Eric , Kater Arnon P.
Published: April 2020

Chronic lymphocytic leukemia (CLL) cells can lose function of P53 and acquire resistance to standard chemotherapy. We found that expression P73, a member of the P53 family, could be induced in CLL cells following CD40-ligation via a c-abl dependent pathway. Induced expression of P73 was associated with re-acquired sensitivity to drugs commonly used treat this disease, such as Fludarabine monophosphate. Similar effects also were noted for CLL cells transduced with an adenovirus vector encoding P731. Prior studies found that P73 also can be induced in breast and colon cancer cell lines following treatment with platinum-based compounds, potentially accounting for the activity of this class of drugs. We hypothesized that treatment of CLL cells with such compound also could induce P73 and that such induced expression also might be associated with re-acquired sensitivity of P53-deficient CLL cells to standard anti-cancer drugs. We studied the mechanisms and effects of platinum-based compounds on CLL cells lacking functional p53. Studies were done with both the p3 dysfunctional pro-lymphocytic celline MEC-1 and with primary CLL cells that lacked functional P53. Treatment of MEC-1 cells with cisplatinum or oxaliplatin induced nuclear translocation of c-Abl in several hours, which was subsequently followed by expression of P73, and then its putative target genes, encoding Bid, p21 and Fas (CD95). Platinum-induced expression of these P73-target genes could be inhibited by co-treatment of the cells with the c-Abl inhibitor imatinib. Cisplatinum treatment of MEC-1 cells resulted in cell cycle arrest. Furthermore, cis-platinum treatment of MEC-1 cells or P53-deficient CLL cells synergized with Fas-mediated apoptosis, and importantly resulted in acquired sensitivity to the drug fludarabine monophosphate in vitro, apparently via a c-Abl dependent pathway. Purified p53 dysfunctional CLL cells obtained before and after 24 and 48 hrs of in vivo cisplatinum treatment revealed de novo expression of both P73 and Bid, illustrating induction of P73 at therapeutic dosages of cisplatin. This study indicates that platinum treatment of CLL cells induces c-Abl dependent expression of P73, which can enhance the sensitivity of P53-deficient CLL cells to drugs such as fludarabine monophosphate. These results provide additional incentive to investigate the activity of platinum-based chemotherapy regimens in patients with refractory disease who have CLL cells lacking functional P53, which currently are ongoing in Europe and the United States.