33 research outputs found

    Allogeneic Stem Cell Transplantation with Sequential Melphalan-Based Conditioning in AML: Residual Morphological Blast Count Determines the Risk of Relapse

    Get PDF
    Introduction: Allogeneic hematopoietic cell transplantation (HCT) during chemotherapy-induced aplasia may offer long-term survival in acute myeloid leukemia (AML) with otherwise poor prognosis including ELN adverse risk, relapsed or refractory disease. However, the value of residual morphologic disease prior HCT in this context has not been conclusively settled until yet. Therefore, we aimed to investigate variables predicting outcome in this unique setting of sequential conditioning therapy, with a focus on pretreatment morphologic blast count. In contrast to the most popular FLAMSA-RIC protocol, we used a melphalan-based conditioning regimen during aplasia. Methods: We retrospectively analyzed data from 173 AML patients who underwent a sequential melphalan-based conditioning therapy between 2003 and 2015 at our centre. All patients participated either in the prospective Phase 2 BRIDGE trial (NCT01295307), the Phase 3 AML2003 study (NCT00180102) or were treated according to this protocol and underwent allogeneic HCT after melphalan-based conditioning in treatment-induced aplasia. Results: Median bone marrow blast count prior to conditioning was 10% (range, 0–96%). Four year probabilities of EFS and OS were 34% (95% CI, 28–43%) and 43% (95% CI, 36–52%), respectively. In multivariate analysis, blast count >20% was associated with worse EFS (HR = 1.93; p = 0.009) and OS (HR = 1.80; p = 0.026). This effect was not significant anymore for HCT during 1st line therapy. Conclusion: Allogeneic HCT in aplasia with a melphalan-based conditioning regimen has the potential to cure a subset of adverse risk AML patients, even with persistent morphological disease prior HCT. However, a high pre-transplant blast count still indicates patients with a dismal prognosis, especially in the relapsed patient group, for whom post-transplant strategies should be considered to further optimize post HCT outcome

    Immunophenotyping of Circulating and Intratumoral Myeloid and T Cells in Glioblastoma Patients

    Get PDF
    Glioblastoma is the most common and lethal primary brain malignancy that almost inevitably recurs as therapy-refractory cancer. While the success of immune checkpoint blockade (ICB) revealed the immense potential of immune-targeted therapies in several types of cancers outside the central nervous system, it failed to show objective responses in glioblastoma patients as of now. The ability of glioblastoma cells to drive multiple modes of T cell dysfunction while exhibiting low-quality neoepitopes, low-mutational load, and poor antigen priming limits anti-tumor immunity and efficacy of antigen-unspecific immunotherapies such as ICB. An in-depth understanding of the GBM immune landscape is essential to delineate and reprogram such immunosuppressive circuits during disease progression. In this view, the present study aimed to characterize the peripheral and intratumoral immune compartments of 35 glioblastoma patients compared to age- and sex-matched healthy control probands, particularly focusing on exhaustion signatures on myeloid and T cell subsets. Compared to healthy control participants, different immune signatures were already found in the peripheral circulation, partially related to the steroid medication the patients received. Intratumoral CD4+ and CD8+ TEM cells (CD62Llow/CD45ROhigh) revealed a high expression of PD1, which was also increased on intratumoral, pro-tumorigenic macrophages/microglia. Histopathological analysis further identified high PSGL-1 expression levels of the latter, which has recently been linked to increased metastasis in melanoma and colon cancer via P-selectin-mediated platelet activation. Overall, the present study comprises immunophenotyping of a patient cohort to give implications for eligible immunotherapeutic targets in neurooncology in the future

    Remission induction versus immediate allogeneic haematopoietic stem cell transplantation for patients with relapsed or poor responsive acute myeloid leukaemia (ASAP): a randomised, open-label, phase 3, non-inferiority trial

    Get PDF
    Background Whether high-dose cytarabine-based salvage chemotherapy, administered to induce complete remission in patients with poor responsive or relapsed acute myeloid leukaemia scheduled for allogeneic haematopoietic stem-cell transplantation (HSCT) after intensive conditioning confers a survival advantage, is unclear. Methods To test salvage chemotherapy before allogeneic HSCT, patients aged between 18 and 75 years with non-favourable-risk acute myeloid leukaemia not in complete remission after first induction or untreated first relapse were randomly assigned 1:1 to remission induction with high-dose cytarabine (3 g/m2 intravenously, 1 g/m2 intravenously for patients >60 years or with a substantial comorbidity) twice daily on days 1–3 plus mitoxantrone (10 mg/m2 intravenously) on days 3–5 or immediate allogeneic HSCT for the disease control group. Block randomisation with variable block lengths was used and patients were stratified by age, acute myeloid leukaemia risk, and disease status. The study was open label. The primary endpoint was treatment success, defined as complete remission on day 56 after allogeneic HSCT, with the aim to show non-inferiority for disease control compared with remission induction with a non-inferiority-margin of 5% and one-sided type 1 error of 2·5%. The primary endpoint was analysed in both the intention-to-treat (ITT) population and in the per-protocol population. The trial is completed and was registered at ClinicalTrials.gov, NCT02461537. Findings 281 patients were enrolled between Sept 17, 2015, and Jan 12, 2022. Of 140 patients randomly assigned to disease control, 135 (96%) proceeded to allogeneic HSCT, 97 (69%) after watchful waiting only. Of 141 patients randomly assigned to remission induction, 134 (95%) received salvage chemotherapy and 128 (91%) patients subsequently proceeded to allogeneic HSCT. In the ITT population, treatment success was observed in 116 (83%) of 140 patients in the disease control group versus 112 (79%) of 141 patients with remission induction (test for non-inferiority, p=0·036). Among per-protocol treated patients, treatment success was observed in 116 (84%) of 138 patients with disease control versus 109 (81%) of 134 patients in the remission induction group (test for non-inferiority, p=0·047). The difference in treatment success between disease control and remission induction was estimated as 3·4% (95% CI –5·8 to 12·6) for the ITT population and 2·7% (–6·3 to 11·8) for the per-protocol population. Fewer patients with disease control compared with remission induction had non-haematological adverse events grade 3 or worse (30 [21%] of 140 patients vs 86 [61%] of 141 patients, χ2 test p<0·0001). Between randomisation and the start of conditioning, with disease control two patients died from progressive acute myeloid leukaemia and zero from treatment-related complications, and with remission induction two patients died from progressive acute myeloid leukaemia and two from treatment-related complications. Between randomisation and allogeneic HSCT, patients with disease control spent a median of 27 days less in hospital than those with remission induction, ie, the median time in hospital was 15 days (range 7–64) versus 42 days (27–121, U test p<0·0001), respectively. Interpretation Non-inferiority of disease control could not be shown at the 2·5% significance level. The rate of treatment success was also not statistically better for patients with remission induction. Watchful waiting and immediate transplantation could be an alternative for fit patients with poor response or relapsed acute myeloid leukaemia who have a stem cell donor available. More randomised controlled intention-to-transplant trials are needed to define the optimal treatment before transplantation for patients with active acute myeloid leukaemia

    SAMHD1 is a biomarker for cytarabine response and a therapeutic target in acute myeloid leukemia.

    Get PDF
    The nucleoside analog cytarabine (Ara-C) is an essential component of primary and salvage chemotherapy regimens for acute myeloid leukemia (AML). After cellular uptake, Ara-C is converted into its therapeutically active triphosphate metabolite, Ara-CTP, which exerts antileukemic effects, primarily by inhibiting DNA synthesis in proliferating cells. Currently, a substantial fraction of patients with AML fail to respond effectively to Ara-C therapy, and reliable biomarkers for predicting the therapeutic response to Ara-C are lacking. SAMHD1 is a deoxynucleoside triphosphate (dNTP) triphosphohydrolase that cleaves physiological dNTPs into deoxyribonucleosides and inorganic triphosphate. Although it has been postulated that SAMHD1 sensitizes cancer cells to nucleoside-analog derivatives through the depletion of competing dNTPs, we show here that SAMHD1 reduces Ara-C cytotoxicity in AML cells. Mechanistically, dGTP-activated SAMHD1 hydrolyzes Ara-CTP, which results in a drastic reduction of Ara-CTP in leukemic cells. Loss of SAMHD1 activity-through genetic depletion, mutational inactivation of its triphosphohydrolase activity or proteasomal degradation using specialized, virus-like particles-potentiates the cytotoxicity of Ara-C in AML cells. In mouse models of retroviral AML transplantation, as well as in retrospective analyses of adult patients with AML, the response to Ara-C-containing therapy was inversely correlated with SAMHD1 expression. These results identify SAMHD1 as a potential biomarker for the stratification of patients with AML who might best respond to Ara-C-based therapy and as a target for treating Ara-C-refractory AML

    Empirical Essays on Retail Logistics and Customer Behavior

    No full text
    Retail logistics is responsible for making products available to end customers. Traditionally, this was facilitated through a network of brick and mortar stores that customers visit to buy items. However, the advent of online and omnichannel retail started to challenge this established system. Modern-day customers increasingly buy a product not solely for its features but also for how, and how fast, the item is delivered and/or returned. Such customer behavior shows that retail logistics often is the decisive factor when searching for, purchasing, and using goods and services. Consequently, logistics performance has become increasingly important for marketing performance. This is in stark contrast to logistics (often) outdated characterization as a back-office operation focusing on cost-effectiveness and lead-time reductions. To overcome the prevailing cost focus, more knowledge is needed that is based on the incorporation of customer behavior into operations management models to demonstrate to retailers the elevated role of logistics in retail today. Therefore, the overall purpose of this dissertation is to contribute to a better understanding of the relevance of logistics in online and omnichannel retail, and its impact on customer behavior. This purpose is explored in four research articles that examine the relevance of logistics from various angles. Article I is a systematic literature review synthesizing empirical literature on the impact of logistics on customer purchase, repurchase, and return behavior in online and omnichannel retail. Article II analyzes how carrying a stock-keeping unit in inventory at the warehouse affects its sales in online retail. Article III investigates how an online retailer’s change in return policy to free returns increases purchases from customers, but also the volume of items being returned to the retailer. Finally, Article IV examines how a buy-online-return-to-store policy in omnichannel retail impacts store performance. The theoretical contributions to the literature are as follows. First, the dissertation illustrates the relevance of logistics in retail today by showing how logistics does not only impact the cost side of a business but also customer behavior and, hence, the demand side. Second, the research highlights the integrative approach that retailers need to adopt between the marketing and operations functions to operate successfully, as action taken by one business function increasingly impacts the other. Third, the dissertation accentuates the role of people in operations management research. It emphasizes how customer behavior is impacted by retail logistics, and thus adds to a better understanding of how people affect real-life operational processes

    Maritime Safety and Security Challenges – 3D Simulation Based Training

    No full text
    Maritime Safety and Security on board ships very much depends on well trained crews. That is why training and exercising emergency response procedures as well as efficiency in reliable management are extremely necessary. On the other hand research as well as technological development in safety and security, tools and other kinds of technical and organizational systems contribute to further improvement and guarantee high levels of safety and security in maritime transportation. Simulation facilities are essential for both exercising and training but also for research and technological development. This paper introduces the innovative concept of a safety and security training simulator (SST7) and describes research work related to the implementation of training scenarios. Selected results of a case study will be presented. A shorter version of this paper was originally presented at the International Conference on &#x201C;Marine Navigation and Safety of Sea Transportation&#x201D; at Gdynia in June 2013

    The impact of free returns on online purchase behavior: Evidence from an intervention at an online retailer

    No full text
    Whether free returns create economic value for online retailers is a question of increasing importance. Using order-level data from an online fashion retailer in Sweden, we investigate the introduction of free returns for customers in Denmark starting November 1, 2017, but not for customers in Sweden, Norway, Finland, France, Germany, and the rest of Europe (the control group). Using difference-in-differences, with and without sample matching, the introduction of free returns increased the order bill by 54.95 Swedish Krona (SEK) (9.15%), product variety per order by 0.057 (8.74%), gross margin per order by 29.90 SEK (9.71%), and returns by 0.195 items per order (7.86%). This likelihood of increased returns was generally similar across different product categories. The findings are robust to parallel trends, event studies, placebo effects, alternative control groups (with Scandinavian countries, Sweden and Norway), country-time trends, and correlations between outcome variables. Based on back-of-the-envelope calculations, the cost of offering free returns is greater than the increase in gross profit driven by free returns. Though our results show that free returns may not be of short-term benefit, retailers must also consider the long-term strategic implications of free returns.peerReviewe

    Ultrasensitive quantification of TAP-dependent antigen compartmentalization in scarce primary immune cell subsets.

    Get PDF
    Presentation of peptides on major histocompatibility complex class I (MHC I) is essential for the establishment and maintenance of self-tolerance, priming of antigen-specific CD8(+) T cells and the exertion of several T-cell effector functions. Cytosolic proteasomes continuously degrade proteins into peptides, which are actively transported across the endoplasmic reticulum (ER) membrane by the transporter associated with antigen processing (TAP). In the ER lumen antigenic peptides are loaded onto MHC I, which is displayed on the cell surface. Here we describe an innovative flow cytometric approach to monitor time-resolved ER compartmentalization of antigenic peptides. This assay allows the analysis of distinct primary human immune cell subsets at reporter peptide concentrations of 1 nM. Thus, this ultrasensitive method for the first time permits quantification of TAP activity under close to physiological conditions in scarce primary cell subsets such as antigen cross-presenting dendritic cells
    corecore