Specific Investigation of Sample Handling Effects on Protease Activities and Absolute Serum Concentrations of Various Putative Peptidome Cancer Biomarkers

# The Author(s) 2010. This article is published with open access at Springerlink.com Introduction In the search for novel cancer biomarkers, various proteolytically derived peptides have been proposed to exhibit cancer or cancer-type specificity. As these peptides are presumably also generated after sample collection by tumor-specific proteases, extensive investigatio

Расчет параметров гидротранспорта высококонцентрированных гидросмесей в условиях предприятий Кривбасса

Для технології складування на підприємствах Кривбасу відходів збагачення, згущених до концентрації пасти, запропоновано методики розрахунків параметрів та режимів роботи/ гідротранспортних установок з урахуванням гідравлічних та реологічних характеристик.The methods of calculation of parameters and regimes of hydrotransport plants operation for technology of stocking of cleaning rejects condensed till paste concentration at Krivbas enterprises taking into account hydraulic and rheological characteristics are offered

Two-stage model-based design of cancer phase I dose escalation trials: evaluation using the phase I program of barasertib (AZD1152)

Introduction Modeling and simulation of pharmacokinetics and pharmacodynamics has previously been shown to be potentially useful in designing Phase I programs of novel anti-cancer agents that show hematological toxicity. In this analysis, a two-stage model-based trial design was evaluated retrospectively using data from the Phase I program with the aurora kinase inhibitor barasertib. Methods Data from two Phase I trials and four regimens were used (n = 79). Using barasertib-hydroxy QPA plasma concentrations and neutrophil count data from only study 1A, a PKPD model was developed and subsequently used to predict the MTD and a safe starting dose for the other trials. Results The PKPD model based on data from the first study adequately described the time course of neutrophil count fluctuation. The two-stage model-based design provided safe starting doses for subsequent phase I trials for barasertib. Predicted safe starting dose levels were higher than those used in two subsequent trials, but lower than used in the other trial. Discussion The two-stage approach could have been applied safely to define starting doses for alternative dosing strategies with barasertib. The limited improvement in efficiency for the phase I program of barasertib may have been due to the fact that starting doses for the studied phase I trials were already nearly optimal. Conclusion Application of the two-stage model-based trial design in Phase I programs with novel anti-cancer drugs that cause haematological toxicity is feasible, safe, and may lead to a reduction in the number of patient treated at sub-therapeutic dose-levels

Two-stage model-based clinical trial design to optimize phase I development of novel anticancer agents

Background The phase I program of anticancer agents usually consists of multiple dose escalation studies to select a safe dose for various administration schedules. We hypothesized that pharmacokinetic and pharmacodynamic (PK–PD) modeling of an initial phase I study (stage 1) can be used for selection of an optimal starting dose for subsequent studies (stage 2) and that a post-hoc PK–PD analysis enhances the selection of a recommended dose for phase II evaluation. The aim of this analysis was to demonstrate that this two-stage model-based design, which does not interfere in the conduct of trials, is safe, efficient and effective. Methods PK and PD data of dose escalation studies were simulated for nine compounds and for five administration regimens (stage 1) for drugs with neutropenia as dose-limiting toxicity. PK–PD models were developed for each simulated study and were used to determine a starting dose for additional phase I studies (stage 2). The model-based design was compared to a conventional study design regarding safety (number of dose-limiting toxicities (DLTs)), efficiency (number of patients treated with a dose below the recommended dose) and effectiveness (precision of dose selection). Retrospective data of the investigational anticancer drug indisulam were used to show the applicability of the model-based design. Results The model-based design was as safe as the conventional design (median number of DLTs = 3) and resulted in a reduction of the number of patients who were treated with a dose below the recommended dose (−27%, power 89%). A post-hoc model-based determination of the recommended dose for future phase II studies was more precise than the conventional selection of the recommended dose (root mean squared error 8.3% versus 30%). Conclusions A two-stage model-based phase I design is safe for anticancer agents with dose-limiting myelosuppression and may enhance the efficiency of dose escalation studies by reducing the number of patients treated with a dose below the recommended dose and by increasing the precision of dose selection for phase II evaluation

BRAF Mutations as Predictive Biomarker for Response to Anti-EGFR Monoclonal Antibodies

Recently, the American Society of Clinical Oncology (ASCO) and the European Society for Medical Oncology (ESMO) recommended that patients with epidermal growth factor receptor (EGFR)-expressing metastatic colorectal cancer could be treated with anti-EGFR monoclonal antibodies (mAbs) cetuximab and panitumumab only in absence of Rat-Sarcoma (RAS) mutations. In addition to the previously established biomarker Kirsten rat sarcoma viral oncogene homolog (KRAS) exon 2, cumulative evidence also shows that patients whose tumors harbor KRAS exons 3 or 4 and neuroblastoma rat-sarcoma viral oncogene homolog (NRAS) exons 2, 3, and 4 mutations are found unlikely to benefit from anti-EGFR treatment.In line with the resistance of RAS mutated (mt) tumors, treatment response in BRAFmt tumors may also be altered given their important role in the EGFR signaling pathway. However, BRAF is not recommended as predictive biomarker yet because the evidence for the impact of BRAF mutations on treatment outcome is considered insufficient.This article summarizes the evidence for the impact of BRAF mutations on treatment outcome of anti-EGFR mAbs. Based on a review of literature, eight meta-analyses were included that consistently show that patients with BRAF mutations have a lack of treatment benefit of anti-EGFR mAbs. After discussing the quality and quantity of available evidence, we conclude that evidence is stronger than suggested by ESMO and ASCO. Additionally, we highlight that the quality of evidence for BRAF is even higher than for extended RAS as a biomarker. We therefore advise ESMO and ASCO to reconsider BRAF status as a predictive biomarker for response. The Oncologist 2017;22:1-9 IMPLICATIONS FOR PRACTICE: In metastatic colorectal cancer (mCRC), therapy with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies cetuximab and panitumumab is indicated in absence of RAS mutations. Cumulative evidence shows that patients with BRAF mutations, who comprise 10% of the mCRC population, do not benefit from anti-EGFR-antibody treatment. Although guidelines state that evidence for BRAF as a predictive marker is insufficient, we highlight that the quality and quantity of evidence is higher than suggested. We therefore encourage the use of BRAF as a predictive marker in order to exclude patients from therapy for whom limited treatment benefit is expected

Extensive Metabolism and Hepatic Accumulation of Gemcitabine After Multiple Oral and Intravenous Administration in Mice

ABSTRACT: In a clinical study with oral gemcitabine (2,2-difluorodeoxycytidine, dFdC), we found that gemcitabine was hepatotoxic and extensively metabolized to 2,2-difluorodeoxyuridine (dFdU) after continuous oral dosing. The main metabolite dFdU had a long terminal half-life after oral administration. Our hypothesis was that dFdU and/or phosphorylated metabolites of gemcitabine accumulated in the liver after multiple oral dosing. In this study, mice were treated with oral or i.v. dFdC at a single dose (1qd؋1d) or at multiple doses once daily for 7 days (1qd؋7d) or seven times daily (7qd؋1d). Blood, liver, kidneys, and lungs were collected at several time points. Urine samples were collected after i.v. dFdC, and peripheral blood mononuclear cells were collected 7qd؋1d dosing of dFdC. The nucleosides dFdC and dFdU as well as the nucleotides gemcitabine monophosphate (dFdC-MP), diphosphate, and triphosphate (dFdC-TP) and dFdU monophosphate, diphosphate (dFdU-DP), and triphosphate (dFdU-TP) were simultaneously quantified by high-performance liquid chromatography with ultraviolet and radioisotope detection. We demonstrate that phosphorylated metabolites of both dFdC and dFdU are formed in mice, primarily consisting of dFdC-MP, dFdC-TP, and dFdU-TP. Multiple dosing of dFdC leads to substantial hepatic and renal accumulation of dFdC-TP and dFdU-TP, which have a more pronounced liver accumulation after oral than after i.v. dosing. The presence of dFdC-MP, dFdC-TP, and dFdU-TP in plasma and urine suggests efflux of these potentially toxic metabolites. Our results show that dFdU, dFdC-TP, and dFdU-TP accumulate in the liver after multiple dosing of dFdC in mice and might be associated with hepatotoxicity of oral dFdC in patients. Gemcitabine (2Ј,2Ј-difluorodeoxycytidine, dFdC), a pyrimidine nucleoside anticancer drug, is used in the treatment of patients with a variety of solid tumors Alternatively, dFdC is deaminated to 2Ј,2Ј-difluorodeoxyuridine (dFdU) by cytidine deaminase (CDA), which is highly expressed in human liver and mice kidney In a clinical study, dFdC was orally administered in continuous dosing regimens at low dose levels in patients with advanced solid tumors . The exposure to dFdC was low because of extensive first-pass metabolism to dFdU. Additionally, we found that the triphosphate form of dFdU (dFdU-TP) was formed at high exposure levels in peripheral blood mononuclear cells (PBMCs). One patient treated with 8 mg of oral dFdC once daily for 14 days of a 21-day cycle developed lethal hepatic toxicity during the second cycle. Pathological examination revealed severe drug-induced liver necrosis. Pharmacokinetic analysis demonstrated that dFdU has a long terminal half-life (t 1/2 ) (ϳ89 h) and appeared to accumulate in the liver of patients. Based on these findings, we hypothesized that continuous daily oral dosing of dFdC results in liver accumulation of dFdU and/or phosphorylated metabolites in patients, possibly associated with the hepatotoxicity of dFdC. We recently found that dFdU is Article, publication date, and citation information can be found at http://dmd.aspetjournals.org. doi:10.1124/dmd.108.021048. ABBREVIATIONS: dFdC, 2Ј,2Ј-difluorodeoxycytidine (gemcitabine); dCK, deoxycytidine kinase; dFdC-MP, gemcitabine monophosphate; dFdC-TP, gemcitabine triphosphate; dFdC-DP, gemcitabine diphosphate; dFdU, 2Ј,2Ј-difluorodeoxyuridine; CDA, cytidine deaminase; dFdU-TP, dFdU triphosphate; PBMC, peripheral blood mononuclear cell; hCNT1, human concentrative nucleoside transporter type 1; PK, pharmacokinetics; 1qdϫ1d, single dose on day 1; 1qdϫ7d, once daily dosing for 7 days; 7qdϫ1d, seven times daily dosing for 1 day; dFdU-MP, dFdU monophosphate; dFdU-DP, dFdU diphosphate; THU, tetrahydrouridine; AP, alkaline phosphatase; HPLC, high-performance liquid chromatography; AUC, area under the curve

Науково-теоретична конференція «Гармонізація науки і вищої освіти в інформаційному суспільстві»

У Києві 30−31 березня 2011 року в Національному авіаційному університеті відбулася науково-теоретична конференція «Гармонізація науки і вищої освіти в інформаційному суспільстві»

Особенности промышленного развития монофункциональных городов Донецкой области

Рассмотрены особенности промышленности моноотраслевых городов Донецкой области. Предлагаются мероприятия по решению проблем их социально-экономического развития.Розглянуто особливості промисловості моногалузевих міст Донецької області. Пропонуються заходи щодо вирішення проблем їх соціально-економічного розвитку.The paper describes the features of the industry in mono-branch cities of Donetsk region. The measures are offered to solve the problems concerning their socio-economic development

Protein versus DNA as a marker for peripheral blood mononuclear cell counting

Quantitative analysis of intracellular analytes requires an accurate and precise assay not only for the quantitation of the analytes, but also for the quantitation of the number of cells in which they were determined. In this technical note we compare protein and DNA as markers for the number of peripheral blood mononuclear cells (PBMCs) isolated from whole blood. The protein content of samples was highly influenced by red blood cell contamination and was, therefore, a less suitable marker. The DNA-based method was unaffected by red blood cell contamination and was finally validated over a range from 10 × 106 to 300 × 106 PBMCs/mL