Feasibility of azacitidine added to standard chemotherapy in older patients with acute myeloid leukemia - a randomised SAL pilot study

INTRODUCTION: Older patients with acute myeloid leukemia (AML) experience short survival despite intensive chemotherapy. Azacitidine has promising activity in patients with low proliferating AML. The aim of this dose-finding part of this trial was to evaluate feasibility and safety of azacitidine combined with a cytarabine- and daunorubicin-based chemotherapy in older patients with AML. TRIAL DESIGN: Prospective, randomised, open, phase II trial with parallel group design and fixed sample size. PATIENTS AND METHODS: Patients aged 61 years or older, with untreated acute myeloid leukemia with a leukocyte count of <20,000/µl at the time of study entry and adequate organ function were eligible. Patients were randomised to receive azacitidine either 37.5 (dose level 1) or 75 mg/sqm (dose level 2) for five days before each cycle of induction (7+3 cytarabine plus daunorubicine) and consolidation (intermediate-dose cytarabine) therapy. Dose-limiting toxicity was the primary endpoint. RESULTS: Six patients each were randomised into each dose level and evaluable for analysis. No dose-limiting toxicity occurred in either dose level. Nine serious adverse events occurred in five patients (three in the 37.5 mg, two in the 75 mg arm) with two fatal outcomes. Two patients at the 37.5 mg/sqm dose level and four patients at the 75 mg/sqm level achieved a complete remission after induction therapy. Median overall survival was 266 days and median event-free survival 215 days after a median follow up of 616 days. CONCLUSIONS: The combination of azacitidine 75 mg/sqm with standard induction therapy is feasible in older patients with AML and was selected as an investigational arm in the randomised controlled part of this phase-II study, which is currently halted due to an increased cardiac toxicity observed in the experimental arm

Feasibility of Azacitidine Added to Standard Chemotherapy in Older Patients with Acute Myeloid Leukemia — A Randomised SAL Pilot Study

Introduction: Older patients with acute myeloid leukemia (AML) experience short survival despite intensive chemotherapy. Azacitidine has promising activity in patients with low proliferating AML. The aim of this dose-finding part of this trial was to evaluate feasibility and safety of azacitidine combined with a cytarabine- and daunorubicin-based chemotherapy in older patients with AML. Trial Design: Prospective, randomised, open, phase II trial with parallel group design and fixed sample size. Patients and Methods: Patients aged 61 years or older, with untreated acute myeloid leukemia with a leukocyte count of ,20,000/ml at the time of study entry and adequate organ function were eligible. Patients were randomised to receive azacitidine either 37.5 (dose level 1) or 75 mg/sqm (dose level 2) for five days before each cycle of induction (7+3 cytarabine plus daunorubicine) and consolidation (intermediate-dose cytarabine) therapy. Dose-limiting toxicity was the primary endpoint. Results: Six patients each were randomised into each dose level and evaluable for analysis. No dose-limiting toxicity occurred in either dose level. Nine serious adverse events occurred in five patients (three in the 37.5 mg, two in the 75 mg arm) with two fatal outcomes. Two patients at the 37.5 mg/sqm dose level and four patients at the 75 mg/sqm level achieved a complete remission after induction therapy. Median overall survival was 266 days and median event-free survival 215 days after a median follow up of 616 days. Conclusions: The combination of azacitidine 75 mg/sqm with standard induction therapy is feasible in older patients with AML and was selected as an investigational arm in the randomised controlled part of this phase-II study, which is currently halted due to an increased cardiac toxicity observed in the experimental arm. Trial Registration: This trial is registered at clinical trials.gov (identifier: NCT00915252)

Pep1, a Secreted Effector Protein of Ustilago maydis, Is Required for Successful Invasion of Plant Cells

The basidiomycete Ustilago maydis causes smut disease in maize. Colonization of the host plant is initiated by direct penetration of cuticle and cell wall of maize epidermis cells. The invading hyphae are surrounded by the plant plasma membrane and proliferate within the plant tissue. We identified a novel secreted protein, termed Pep1, that is essential for penetration. Disruption mutants of pep1 are not affected in saprophytic growth and develop normal infection structures. However, Δpep1 mutants arrest during penetration of the epidermal cell and elicit a strong plant defense response. Using Affymetrix maize arrays, we identified 116 plant genes which are differentially regulated in Δpep1 compared to wild type infections. Most of these genes are related to plant defense. By in vivo immunolocalization, live-cell imaging and plasmolysis approaches, we detected Pep1 in the apoplastic space as well as its accumulation at sites of cell-to-cell passages. Site-directed mutagenesis identified two of the four cysteine residues in Pep1 as essential for function, suggesting that the formation of disulfide bridges is crucial for proper protein folding. The barley covered smut fungus Ustilago hordei contains an ortholog of pep1 which is needed for penetration of barley and which is able to complement the U. maydis Δpep1 mutant. Based on these results, we conclude that Pep1 has a conserved function essential for establishing compatibility that is not restricted to the U. maydis / maize interaction

The Ustilago hordei-Barley Interaction is a Versatile System for Characterization of Fungal Effectors

Obligate biotrophic fungal pathogens, such as Blumeria graminis and Puccinia graminis, are amongst the most devastating plant pathogens, causing dramatic yield losses in many economically important crops worldwide. However, a lack of reliable tools for the efficient genetic transformation has hampered studies into the molecular basis of their virulence or pathogenicity. In this study, we present the Ustilago hordei-barley pathosystem as a model to characterize effectors from different plant pathogenic fungi. We generate U. hordei solopathogenic strains, which form infectious filaments without the presence of a compatible mating partner. Solopathogenic strains are suitable for heterologous expression system for fungal virulence factors. A highly efficient Crispr/Cas9 gene editing system is made available for U. hordei. In addition, U. hordei infection structures during barley colonization are analyzed using transmission electron microscopy, showing that U. hordei forms intracellular infection structures sharing high similarity to haustoria formed by obligate rust and powdery mildew fungi. Thus, U. hordei has high potential as a fungal expression platform for functional studies of heterologous effector proteins in barley

CONSORT statement.

<p>The patient flow through this dose finding pilot trial is shown.</p

Outcome of the entire trial population.

<p>A: overall survival, B: event-free survival.</p

Listing of all severe adverse events and adverse events grade 3 or 4.

<p>The highest CTCAE grade of each event is listed. Hematotoxicity was not listed as adverse event unless persisting >42 days with grade IV after start of the last chemotherapy cycle without evidence of persisting leukemia.</p><p>Abbreviations: AZA, 5-azacitidine; CTCAE, common terminology criteria for adverse events; SAE, serious adverse event.</p>a<p>In patient 7, both SAEs were documented with a fatal outcome.</p

Hematotoxicity of induction and consolidation therapy.

<p>The time from start of chemotherapy until regeneration of leukocytes >1,000/µl, neutrophils >500/µl and plateletes >20,000/µl (transfusion independent) is shown. A: induction therapy, B: consolidation therapy.</p

Patient characteristics and outcome of the 12 patients included into the trial.

<p>Abbreviations: ASXL1, additional sex combs like 1; AZA, 5-azacitidine; BM, bone marrow; CR, complete remission; FLT3, fms-like tyrosine kinase 3; IDH, isocitrate dehydrogenase; ITD, internal tandem duplication; NPM1, Nucleophosmin 1; PS, ECOG performance status; TET2, ten-eleven translocation 2.</p>a<p>Presence of a sole trisomy in each of two clones.</p>b<p>Mutational analysis revealed wildtype status for NPM and no FLT3-ITD. Analysis of ASXL1, DNMT3A, IDH1, IDH2 and TET2 could not be performed due to lack of material.</p>c<p>In patient 10, CR was achieved after trial termination without further therapy.</p>d<p>Relapse after achievement of CR by salvage therapy.</p