181 research outputs found

    Performance of Different Diagnostic PD-L1 Clones in Head and Neck Squamous Cell Carcinoma

    Get PDF
    Background: The approval of immune checkpoint inhibitors in combination with specific diagnostic biomarkers presents new challenges to pathologists as tumor tissue needs to be tested for expression of programmed death-ligand 1 (PD-L1) for a variety of indications. As there is currently no requirement to use companion diagnostic assays for PD-L1 testing in Germany different clones are used in daily routine. While the correlation of staining results has been tested in various entities, there is no data for head and neck squamous cell carcinomas (HNSCC) so far. Methods: We tested five different PD-L1 clones (SP263, SP142, E1L3N, 22-8, 22C3) on primary HNSCC tumor tissue of 75 patients in the form of tissue microarrays. Stainings of both immune and tumor cells were then assessed and quantified by pathologists to simulate real-world routine diagnostics. The results were analyzed descriptively and the resulting staining pattern across patients was further investigated by principal component analysis and non-negative matrix factorization clustering. Results: Percentages of positive immune and tumor cells varied greatly. Both the resulting combined positive score as well as the eligibility for certain checkpoint inhibitor regimens was therefore strongly dependent on the choice of the antibody. No relevant co-clustering and low similarity of relative staining patterns across patients was found for the different antibodies. Conclusions: Performance of different diagnostic anti PD-L1 antibody clones in HNSCC is less robust and interchangeable compared to reported data from other tumor entities. Determination of PD-L1 expression is critical for therapeutic decision making and may be aided by back-to-back testing of different PD-L1 clones

    Improved diagnostics targeting c-MET in non-small cell lung cancer: expression, amplification and activation?

    Get PDF
    Background: Several c-MET targeting inhibitory molecules have already shown promising results in the treatment of patients with Non-small Cell Lung Cancer (NSCLC). Combination of EGFR-and c-MET-specific molecules may overcome EGFR tyrosine kinase inhibitor (TKI) resistance. The aim of this study was to allow for the identification of patients who might benefit from TKI treatments targeting MET and to narrow in on the diagnostic assessment of MET. Methods: 222 tumor tissues of patients with NSCLC were analyzed concerning c-MET expression and activation in terms of phosphorylation (Y1234/1235 and Y1349) using a microarray format employing immunohistochemistry (IHC). Furthermore, protein expression and MET activation was correlated with the amplification status by Fluorescence in Situ Hybridization (FISH). Results: Correlation was observed between phosphorylation of c-MET at Y1234/1235 and Y1349 (spearman correlation coefficient r(s) = 0.41;p 0.05). c-MET gene amplification was detected in eight of 214 patients (3.7 %). No significant association was observed between c-MET amplification, c-MET protein expression and phosphorylation. Conclusion: Our data indicate, that neither expression of c-MET nor the gene amplification status might be the best way to select patients for MET targeting therapies, since no correlation with the activation status of MET was observed. We propose to take into account analyzing the phosphorylation status of MET by IHC to select patients for MET targeting therapies. Signaling of the receptor and the activation of downstream molecules might be more crucial for the benefit of therapeutics targeting MET receptor tyrosine kinases than expression levels alone

    The significance of trust in the political system and motivation for pupils' learning progress in politics lessons

    Full text link
    Very little research has been conducted on the contribution of political education to learning progress in Germany. Hence, there is a need for intervention studies measuring performance against the theoretical background of a political competence model. This model comprises three constructs: subject knowledge, motivation and attitudes. According to this model, politics lessons should not only convey knowledge but also arouse subject interest, promote political attitudes and develop problem-solving skills. This study investigates how knowledge acquisition is influenced by intervention using theory-oriented teaching materials on the European Union, intervention using conventional textbooks on the European Union and politics lessons without any reference to the European Union. It further asks how the performance-related self-concept and subject interest in political issues impact political knowledge and whether civic virtue and trust in the system are related to it. The sample comprises 1071 pupils. Theory-oriented politics classes lead to greater growth of pupils’ knowledge than in the control group. As anticipated, this study proves that a positive subject-specific self-concept impacts knowledge. The examination of political attitudes reveals a positive correlation between civic virtue and knowledge. There is no connection between trust in the political system and knowledge

    Implementing a system of quality-of-life diagnosis and therapy for breast cancer patients: results of an exploratory trial as a prerequisite for a subsequent RCT

    Get PDF
    A system for quality-of-life diagnosis and therapy (QoL system) was implemented for breast cancer patients. The system fulfilled the criteria for complex interventions (Medical Research Council). Following theory and modeling, this study contains the exploratory trial as a next step before the randomised clinical trial (RCT) answering three questions: (1) Are there differences between implementation sample and general population? (2) Which amount and type of disagreement exist between patient and coordinating practitioners (CPs) in assessed global QoL? (3) Are there empirical reasons for a cutoff of 50 points discriminating between healthy and diseased QoL? Implementation was successful: 74% of CPs worked along the care pathway. However, CPs showed preferences for selecting patients with lower age and UICC prognostic staging. Patients and CPs disagreed considerably in values of global QoL, despite education in QoL assessment by outreach visits, opinion leaders and CME: Zero values of QoL were only expressed by patients. Finally, the cutoff of 50 points was supported by the relationship between QoL in single items and global QoL: no patients with values above 50 dropped global QoL below 50, but values below 50 and especially at 0 points in single items, induced a dramatic fall of global QoL down to below 50. The exploratory trial was important for defining the complex intervention in the definitive RCT: control for age and prognostic stage grading, support for a QoL unit combining patient's and CP's assessment of QoL and support for the 50-point cutoff criterion between healthy and diseased QoL

    Entropy Measures Quantify Global Splicing Disorders in Cancer

    Get PDF
    Most mammalian genes are able to express several splice variants in a phenomenon known as alternative splicing. Serious alterations of alternative splicing occur in cancer tissues, leading to expression of multiple aberrant splice forms. Most studies of alternative splicing defects have focused on the identification of cancer-specific splice variants as potential therapeutic targets. Here, we examine instead the bulk of non-specific transcript isoforms and analyze their level of disorder using a measure of uncertainty called Shannon's entropy. We compare isoform expression entropy in normal and cancer tissues from the same anatomical site for different classes of transcript variations: alternative splicing, polyadenylation, and transcription initiation. Whereas alternative initiation and polyadenylation show no significant gain or loss of entropy between normal and cancer tissues, alternative splicing shows highly significant entropy gains for 13 of the 27 cancers studied. This entropy gain is characterized by a flattening in the expression profile of normal isoforms and is correlated to the level of estimated cellular proliferation in the cancer tissue. Interestingly, the genes that present the highest entropy gain are enriched in splicing factors. We provide here the first quantitative estimate of splicing disruption in cancer. The expression of normal splice variants is widely and significantly disrupted in at least half of the cancers studied. We postulate that such splicing disorders may develop in part from splicing alteration in key splice factors, which in turn significantly impact multiple target genes

    Specific induction of pp125 focal adhesion kinase in human breast cancer

    Get PDF
    The pp125 focal adhesion kinase (FAK) is involved in integrin-mediated cell signalling and overexpressed in a variety of solid tumours. Focal adhesion kinase expression has been correlated to invasion and metastasis, but the data on breast cancer are inconclusive. We analysed FAK mRNA, protein levels and expression patterns in primary breast cancer and normal breast tissue. FAK expression on the functional protein level and mRNA was determined in 55 matched pairs of breast cancer and corresponding normal tissue by Western blot, immunohistochemistry and RT–PCR. Using a score ranging from 0 to +5 for Western blots, we determined in normal breast tissue a score of 1.51±0.84 (mean±standard deviation), which was strongly induced to 2.91 (±1.22) in breast cancers (P<0.001). Overall, 45 out of 55 tissue pairs (81.8%) showed this upregulation of FAK protein in tumours in comparison to normal tissue. Immunohistochemistry confirmed these findings with a significant higher score for tumours vs physiological tissue (1.0±0.63 vs 2.27±0.91; P=0.001). Interestingly, no overall significant difference in the mRNA levels (P=0.359) was observed. In conclusion, expression levels of the FAK protein are specifically upregulated in breast cancer in comparison to matched normal breast tissue supporting its pivotal role in neoplastic signal transduction and representing a potential marker for malignant transformation

    The development of study-specific self-efficacy during grammar school.(Zur Entwicklung der studienspezifischen Selbstwirksamkeit in der Oberstufe)

    Get PDF
    Article is in German. Even if more and more German adolescents acquire a university entrance qualification, not all of them finally enrol at a university. In particular, the transition from school to university strongly depends on parent’s education. Even with the same marks in school, adolescents from non-academic households are less likely to enrol in universities than adolescents from academic housholds. One important reason is their lower belief to master a university study. This study analyses a specific intervention in grammar school to improve study-specific self- efficacy, the belief in one’s capabilities to master a university study, using a longitudinal design. We apply a difference-in-difference framework and show that programme participation significantly improves the study-specific self-efficacy for puplis from non- academic families but not for those from academic families. Hence, such a programme could reduce social disparities between both groups
    • …
    corecore