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BackgroundWe performed a clinical audit of preoperative rectal cancer treatment at two European radiotherapy centres (Poland and Spain). The aim was to independently verify adherence to a selection of indicators of treatment quality and to identify any notable inter-institutional differences.MethodsA total of 162 patients, in Catalan Institute of Oncology (ICO) 68 and in Greater Poland Cancer Centre (GPCC) 94, diagnosed with locally advanced rectal cancer and treated with preoperative radiotherapy or radio-chemotherapy were included in retrospective study. A total of 7 quality control measures were evaluated: waiting time, multidisciplinary treatment approach, portal verification, in vivo dosimetry, informed consent, guidelines for diagnostics and therapy, and patient monitoring during treatment.ResultsSeveral differences were observed. Waiting time from pathomorphological diagnosis to initial consultation was 31 (ICO) vs. 8 (GPCC) days. Waiting time from the first visit to the beginning of the treatment was twice as long at the ICO. At the ICO, 82% of patient experienced treatment interruptions. The protocol for portal verification was the same at both institutions. In vivo dosimetry is not used for this treatment localization at the ICO. The ICO utilizes locally-developed guidelines for diagnostics and therapy, while the GPCC is currently developing its own guidelines.ConclusionsAn independent external clinical audit is an excellent approach to identifying and resolving deficiencies in quality control procedures. We identified several procedures amenable to improvement. Both institutions have since implemented changes to improve quality standards. We believe that all radiotherapy centres should perform a comprehensive clinical audit to identify and rectify deficiencies.

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Backgroundβ-cells undergo an epithelial to mesenchymal transition (EMT) when expanded in monolayer culture and give rise to highly proliferative mesenchymal cells that retain the potential to re-differentiate into insulin-producing cells.ObjectiveTo investigate whether EMT takes place in the endocrine non-β cells of human islets.MethodologyHuman islets isolated from 12 multiorgan donors were dissociated into single cells, purified by magnetic cell sorting, and cultured in monolayer.ResultsCo-expression of insulin and the mesenchymal marker vimentin was identified within the first passage (p1) and increased subsequently (insulin+vimentin+ 7.2±6% at p1; 43±15% at p4). The endocrine non-β-cells did also co-express vimentin (glucagon+vimentin+ 59±1.5% and 93±6%, somatostatin+vimentin+ 16±9.4% and 90±10% at p1 and p4 respectively; PP+vimentin+ 74±14% at p1; 88±12% at p2). The percentage of cells expressing only endocrine markers was progressively reduced (0.6±0.2% insulin+, 0.2±0.1% glucagon+, and 0.3±0.2% somatostatin+ cells at p4, and 0.7±0.3% PP+ cells at p2. Changes in gene expression were also indicated of EMT, with reduced expression of endocrine markers and the epithelial marker CDH-1 (p<0.01), and increased expression of mesenchymal markers (CDH-2, SNAI2, ZEB1, ZEB2, VIM, NT5E and ACTA2; p<0.05). Treatment with the EMT inhibitor A83-01 significantly reduced the percentage of co-expressing cells and preserved the expression of endocrine markers.ConclusionsIn adult human islets, all four endocrine islet cell types undergo EMT when islet cells are expanded in monolayer conditions. The presence of EMT in all islet endocrine cells could be relevant to design of strategies aiming to re-differentiate the expanded islet cells towards a β-cell phenotype.

As radiotherapy practice and processes become more complex, the need to assure quality control becomes ever greater. At present, no international consensus exists with regards to the optimal quality control indicators for radiotherapy; moreover, few clinical audits have been conducted in the field of radiotherapy. The present article describes the aims and current status of the international IROCA "Improving Radiation Oncology Through Clinical Audits" project. The project has several important aims, including the selection of key quality indicators, the design and implementation of an international audit, and the harmonization of key aspects of radiotherapy processes among participating institutions. The primary aim is to improve the processes that directly impact clinical outcomes for patients. The experience gained from this initiative may serve as the basis for an internationally accepted clinical audit model for radiotherapy.

BackgroundRadiation-induced DNA double-strand break (DSB) repair can be tested by using pulsed-field gel electrophoresis (PFGE) in agarose-encapsulated cells. However, previous studies have reported that this assay is impaired by the spontaneous DNA breakage in this medium. We investigated the mechanisms of this fragmentation with the principal aim of eliminating it in order to improve the estimation of radiation-induced DNA repair.MethodsSamples from cancer cell cultures or xenografted tumours were encapsulated in agarose plugs. The cell plugs were then irradiated, incubated to allow them to repair, and evaluated by PFGE, caspase-3, and histone H2AX activation (γH2AX). In addition, apoptosis inhibition was evaluated through chemical caspase inhibitors.ResultsWe confirmed that spontaneous DNA fragmentation was associated with the process of encapsulation, regardless of whether cells were irradiated or not. This DNA fragmentation was also correlated to apoptosis activation in a fraction of the cells encapsulated in agarose, while non-apoptotic cell fraction could rejoin DNA fragments as was measured by γH2AX decrease and PFGE data. We were able to eliminate interference of apoptosis by applying specific caspase inhibitors, and improve the estimation of DNA repair, and apoptosis itself.ConclusionsThe estimation of radiation-induced DNA repair by PFGE may be improved by the use of apoptosis inhibitors. The ability to simultaneously determine DNA repair and apoptosis, which are involved in cell fate, provides new insights for using the PFGE methodology as functional assay.

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