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Adaptation of wild-type p53 expressing UKF-NB-3 cancer cells to the murine double minute 2 inhibitor nutlin-3 causes de novo p53 mutations at high frequency (13/20) and multi-drug resistance. Here, we show that the same cells respond very differently when adapted to RITA, a drug that, like nutlin-3, also disrupts the p53/Mdm2 interaction. All of the 11 UKF-NB-3 sub-lines adapted to RITA that we established retained functional wild-type p53 although RITA induced a substantial p53 response. Moreover, all RITA-adapted cell lines remained sensitive to nutlin-3, whereas only five out of 10 nutlin-3-adapted cell lines retained their sensitivity to RITA. In addition, repeated adaptation of the RITA-adapted sub-line UKF-NB-3(r)RITA(10 mu M) to nutlin-3 resulted in p53 mutations. The RITA-adapted UKF-NB-3 sub-lines displayed no or less pronounced resistance to vincristine, cisplatin, and irradiation than nutlin-3-adapted UKF-NB-3 sub-lines. Furthermore, adaptation to RITA was associated with fewer changes at the expression level of antiapoptotic factors than observed with adaptation to nutlin-3. Transcriptomic analyses indicated the RITA-adapted sub-lines to be more similar at the gene expression level to the parental UKF-NB-3 cells than nutlin-3-adapted UKF-NB-3 sub-lines, which correlates with the observed chemotherapy and irradiation sensitivity phenotypes. In conclusion, RITA-adapted cells retain functional p53, remain sensitive to nutlin-3, and display a less pronounced resistance phenotype than nutlin-3-adapted cells. Cell Death and Disease (2012) 3, e294; doi:10.1038/cddis.2012.35; published online 5 April 2012

The human cytomegalovirus (HCMV) is suspected to increase tumour malignancy by infection of cancer and/or stroma cells (oncomodulation). So far, oncomodulatory mechanisms have been attributed to the presence of HCMV and direct action of its gene products on cancer cells. Here, we investigated whether the prolonged presence of HCMV can result in the irreversible selection of a cancer cell population with increased malignancy. The neuroblastoma cell line UKF-NB-4 was long-term (200 passages) infected with the HCMV strain Hi91 (UKF-NB-4Hi) before virus eradication using ganciclovir (UKF-NB-4HiGCV). Global gene expression profiling of UKF-NB-4, UKF-NB-4Hi and UKF-NB-4HiGCV cells and subsequent bioinformatic signal transduction pathway analysis revealed clear differences between UKF-NB-4 and UKF-NB-4Hi, as well as between UKF-NB-4 and UKF-NB-4HiGCV cells, but only minor differences between UKF-NB-4Hi and UKF-NB-4HiGCV cells. Investigation of the expression of a subset of five genes in different chronically HCMV-infected cell lines before and after virus eradication suggested that long-term HCMV infection reproducibly causes specific changes. Array comparative genomic hybridisation showed virtually the same genomic differences for the comparisons UKF-NB-4Hi/UKF-NB-4 and UKF-NB-4HiGCV/UKF-NB-4. UKF-NB-4Hi cells are characterised by an increased invasive potential compared with UKF-NB-4 cells. This phenotype was completely retained in UKF-NB-4HiGCV cells. Moreover, there was a substantial overlap in the signal transduction pathways that differed significantly between UKF-NB-4Hi/UKF-NB-4HiGCV and UKF-NB-4 cells and those differentially regulated between tumour tissues from neuroblastoma patients with favourable or poor outcome. In conclusion, we present the first experimental evidence that long-term HCMV infection can result in the selection of tumour cell populations with enhanced malignancy.

The undisputed increase of the relevance of mental work load is confronted with a lack of qualified or at least well documented measuring instruments covering all important aspects.The COPSOQ (Copenhagen Psychosocial Questionnaire), a comprehensive instrument for the assessment of psychosocial factors at work, was tested in a partly modified version in a large German sample (N = 2561 employees). The aims of the study were the detailed investigation of the psychometric measurement properties, and based on these results, the development of an abbreviated version of the instrument.The analysis of objectivity, acceptance, practicability, sensitivity and content validity of the questionnaire as a whole did not show any problematic results - with some limitations regarding the length of the questionnaire.The assessment of the reliability, generalisability, construct validity, criterion validity and diagnostic power of the single scales showed medium to good measuring qualities for the majority of the scales (i.e. Cronbach's alpha mostly >0.7). In addition, the psychometric properties were very similar to those in the Danish COPSOQ-study.Considering all aspects of the measurement quality, a shortened version of the instrument was created. It attempts to combine measuring qualities as high as possible with a number of questions as low as possible.The German COPSOQ questionnaire is a free screening-instrument for the recording of psychosocial work load and strain for all enterprises and organisations interested. The next step is the construction of a "job exposure matrix" for psychosocial factors at work, that means a central database with work load profiles and reference values for as many occupational groups as possible., Der unbestrittenen Zunahme der Relevanz psychischer Belastungen bei der Arbeit steht bisher ein Mangel an inhaltlich umfassenden und gesichert qualifizierten oder zumindest transparent dokumentierten Messinstrumenten gegenüber.Der inhaltlich sehr breit angelegte dänische COPSOQ-Fragebogen (Copenhagen Psychosocial Questionnaire) zur Erfassung psychosozialer Faktoren bei der Arbeit wurde in einer umfangreichen Stichprobe (N = 2561 Beschäftigte) in Deutschland in teilweise modifizierter Fassung erprobt. Ziele waren die detaillierte Prüfung der psychometrischen Messeigenschaften, sowie darauf aufbauend die Erstellung einer verkürzten Fassung des Instruments.Bei der Prüfung der Messmethode und des Messinstrumentes insgesamt gab es bezüglich der Objektivität, Akzeptanz, Praktikabilität, Sensitivität und Inhaltsvalidität - mit Abstrichen bezüglich der Länge des Fragebogens - keine problematischen Befunde.Die Prüfung der einzelnen Skalen auf Reliabilität, Generalisierbarkeit, Konstruktvalidität, Kriteriumsvalidität und diagnostische Aussagekraft ergab für die Mehrzahl der Skalen brauchbare bis gute Messeigenschaften (z.B. Cronbach's alpha meist >0,7), die außerdem den dänischen Ergebnissen sehr ähnlich waren.Unter Würdigung aller geprüften Aspekte der Messqualität wurde ein verkürztes Instrument erstellt, das versucht, möglichst hohe Messqualitäten mit einer möglichst geringen Fragenanzahl zu verbinden.Die deutsche Version des COPSOQ steht nunmehr als Screening-Instrument zur Erfassung psychischer Belastungen und Beanspruchungen bei der Arbeit Betrieben und Organisationen kostenfrei zur Verfügung. Besonders lohnend erscheint nun der Aufbau einer "job-exposure matrix" im Bereich der psychosozialen Faktoren bei der Arbeit, also einer zentralen Datenbank mit Belastungsprofilen und Referenzwerten für möglichst viele Berufsgruppen.