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Membrane transporters are important determinants of drug bioavailability. Their expression and activity affect the intracellular drug concentration in leukemic cells impacting response to therapy. Pharmacogenomics represents genetic markers that reflect allele arrangement of genes encoding drug transporters associated with treatment response. In previous work, we identified SNP rs460089 located in the promotor of SLC22A4gene encoding imatinib transporter OCTN1 as influential on response of patients with chronic myeloid leukemia treated with imatinib. Patients with rs460089-GC pharmacogenotype had significantly superior response to first-line imatinib treatment compared to patients with rs460089-GG. This study investigated whether pharmacogenotypes of rs460089 are associated with sustainability of treatment-free remission (TFR) in patients from the EUROpean Stop Kinase Inhibitor (EURO-SKI) trial. In the learning sample, 176 patients showed a significantly higher 6-month probability of molecular relapse free survival (MRFS) in patients with GC genotype (73%, 95% CI: 60–82%) compared to patients with GG (51%, 95% CI: 41–61%). Also over time, patients with GC genotype had significantly higher MRFS probabilities compared with patients with GG (HR: 0.474, 95% CI: 0.280-0.802, p= 0.0054). Both results were validated with data on 93 patients from the Polish STOP imatinib study. In multiple regression models, in addition to the investigated genotype, duration of TKI therapy (EURO-SKI trial) and duration of deep molecular response (Polish study) were identified as independent prognostic factors. The SNP rs460089 was found as an independent predictor of TFR.

Several studies have reported that chronic myeloid leukaemia (CML) patients expressing e14a2 BCR::ABL1have a faster molecular response to therapy compared to patients expressing e13a2. To explore the reason for this difference we undertook a detailed technical comparison of the commonly used Europe Against Cancer (EAC) BCR::ABL1reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) assay in European Treatment and Outcome Study (EUTOS) reference laboratories (n= 10). We found the amplification ratio of the e13a2 amplicon was 38% greater than e14a2 (p= 0.015), and the amplification efficiency was 2% greater (P= 0.17). This subtle difference led to measurable transcript-type dependent variation in estimates of residual disease which could be corrected by (i) taking the qPCR amplification efficiency into account, (ii) using alternative RT-qPCR approaches or (iii) droplet digital PCR (ddPCR), a technique which is relatively insensitive to differences in amplification kinetics. In CML patients, higher levels of BCR::ABL1/GUSBwere identified at diagnosis for patients expressing e13a2 (n= 67) compared to e14a2 (n= 78) when analysed by RT-qPCR (P= 0.0005) but not ddPCR (P= 0.5). These data indicate that widely used RT-qPCR assays result in subtly different estimates of disease depending on BCR::ABL1transcript type; these differences are small but may need to be considered for optimal patient management.

Protein corona formation has been regarded as an obstacle to developing diagnostic and therapeutic nanoparticles for in vivoapplications. Serum proteins that assemble around nanoparticles can hinder their targeting efficiency. Virus-based nanoparticles should be naturally predisposed to evade such barriers in host organisms. Here, we demonstrate that virus-like particles derived from mouse polyomavirus do not form a rich protein corona. These particles can be efficiently targeted to cells that overproduce transferrin receptors, e.g., cancer cells, by conjugating transferrin to the particle surface. In this study, we provide evidence that the interaction of virus-like particles with their newly assigned target receptor is not obstructed by serum proteins. The particles enter target cells via a clathrin-dependent endocytic pathway that is not naturally used by the virus. Our results support the notion that the natural properties of virus-like particles make them well-suited for development of nanosized theranostic tools resistant to detargeting by protein coronas.

Background:The TIGER-trial (NCT01657604) is a multicenter, randomized phase III study to evaluate efficacy and tolerability of nilotinib (NIL) vs NIL+pegylated interferon alpha2b (IFN) combination therapy with IFN maintenance as first-line treatment for patients (pts) with chronic myeloid leukemia (CML) in chronic phase.

Introduction

Background

Glutamate carboxypeptidase II (GCPII) is a membrane protease overexpressed by prostate cancer cells and detected in the neovasculature of most solid tumors. Targeting GCPII with inhibitor-bearing nanoparticles can enable recognition, imaging, and delivery of treatments to cancer cells. Compared to methods based on antibodies and other large biomolecules, inhibitor-mediated targeting benefits from the low molecular weight of the inhibitor molecules, which are typically stable, easy-to-handle, and able to bind the enzyme with very high affinity. Although GCPII is established as a molecular target, comparing previously reported results is difficult due to the different methodological approaches used. In this work, we investigate the robustness and limitations of GCPII targeting with a diverse range of inhibitor-bearing nanoparticles (various structures, sizes, bionanointerfaces, conjugation chemistry, and surface densities of attached inhibitors). Polymer-coated nanodiamonds, virus-like particles based on bacteriophage Qβ and mouse polyomavirus, and polymeric poly(HPMA) nanoparticles with inhibitors attached by different means were synthesized and characterized. We evaluated their ability to bind GCPII and interact with cancer cells using surface plasmon resonance, inhibition assay, flow cytometry, and confocal microscopy. Regardless of the diversity of the investigated nanosystems, they all strongly interact with GCPII (most with low picomolar Kivalues) and effectively target GCPII-expressing cells. The robustness of this approach was limited only by the quality of the nanoparticle bionanointerface, which must be properly designed by adding a sufficient density of hydrophilic protective polymers. We conclude that the targeting of cancer cells overexpressing GCPII is a viable approach transferable to a broad diversity of nanosystems.

Background

AIM: To compare the efficacy and safety of two analog insulins as starting regimens in insulin-nave Type 2 diabetes patients. METHODS: In this randomized, open-label parallel study, twice-daily biphasic insulin aspart 30 (30% soluble and 70% protaminated insulin aspart; BIAsp 30) plus metformin (met) was compared with once-daily insulin glargine (glarg) plus glimepiride (glim) in 255 insulin-nave patients (131 male; meanSD age, 61.29.1 years). Mean baseline HbA 1c (SD) was 9.21.4% and 8.91.3% for BIAsp 30 plus met ( N=128) and glarg plus glim ( N=127), respectively ( P=0.0747). Primary endpoint was the difference in absolute change in HbA 1c between groups after 26 weeks of treatment. RESULTS: HbA 1c change was significantly greater in the BIAsp 30 plus met group than the glarg plus glim group (between-group difference: -0.5% (95% CI: -0.8; -0.2); P=0.0002). Mean prandial plasma glucose increment was significantly lower for BIAsp 30 plus met compared with glarg plus glim: 1.41.4 mmol/l vs. 2.21.8 mmol/l; P=0.0002. During the maintenance phase (weeks 6-26), one major hypoglycemic episode occurred in each group; 20.3% and 9% of patients experienced minor hypoglycemic episodes in the BIAsp 30 plus met and glarg plus glim groups, respectively ( P=0.0124). At end-of-trial, mean daily insulin doses were 0.40 U/kg BIAsp 30 and 0.39 U/kg glarg. Glarg plus glim-treated patients experienced significant weight gain of 1.5 kg (95% CI: 0.84; 2.19; P<0.0001). Weight change with BIAsp 30 plus met of +0.7 kg was not statistically significant (95% CI: -0.07; 1.42; P=0.0762). CONCLUSIONS: Starting insulin in Type 2 diabetes patients with twice-daily BIAsp 30 plus met can reduce HbA 1c and mean prandial plasma glucose increment to a greater extent than once-daily glarg plus glim.

The detection and quantification of BCR-ABL1 transcripts play a key role in therapy management of chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitors (TKIs). Reverse transcription quantitative PCR (RT-qPCR) is considered the gold standard strategy for monitoring of minimal residual disease (MRD). Recently, digital PCR (dPCR) was introduced as a new quantification method based on determination of absolute target sequence quantity. In connection with the deep molecular response (MR) assessment and the option of TKIs treatment cessation, the dPCR has a potential of high sensitivity, robustness and accuracy of BCR-ABL1 transcripts detection. The aim of present work was to compare the results of two standardized RT-qPCR methods with RT-dPCR detection in clinical samples of CML patients with different BCR-ABL1 fusion transcripts level.

Pfirrmann: BMS: Consultancy, Honoraria; Novartis Pharma: Consultancy, Honoraria. Hasford:Novartis: Research Funding. Saussele:Novartis Pharma: Honoraria, Other: Travel grant, Research Funding; BMS: Honoraria, Other: Travel grant, Research Funding; ARIAD: Honoraria; Pfizer: Honoraria, Other: Travel grant. Turkina:Bristol Myers Squibb: Consultancy; Pfizer: Consultancy; Novartis Pharma: Consultancy. Prejzner:Novartis Pharma: Honoraria; BMS: Honoraria. Steegmann:Novartis Pharma: Consultancy, Honoraria, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding. Simonsson:Novartis Pharma: Research Funding. Zaritskey:University of Heidelberg: Research Funding; Novartis: Consultancy. Zackova:Novartis Pharma: Consultancy; Bristol Myers Squibb: Consultancy. Janssen:Novartis: Research Funding; Pfizer: Consultancy; Bristol Myers Squibb: Consultancy; ARIAD: Consultancy. Cervantes:Novartis: Consultancy, Speakers Bureau; Sanofi-Aventis: Consultancy; CTI-Baxter: Consultancy, Speakers Bureau. Hehlmann:Novartis Pharma: Research Funding; BMS: Consultancy. Baccarani:Novartis: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Pfizer: Consultancy, Honoraria, Speakers Bureau; Ariad: Consultancy, Speakers Bureau.

Zdenek: Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Klamova:Novartis and Bristol Myers-Squibb: Consultancy, Honoraria. Mayer:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.