18 research outputs found

    Systematic Bias in Genomic Classification Due to Contaminating Non-neoplastic Tissue in Breast Tumor Samples

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    Abstract Background Genomic tests are available to predict breast cancer recurrence and to guide clinical decision making. These predictors provide recurrence risk scores along with a measure of uncertainty, usually a confidence interval. The confidence interval conveys random error and not systematic bias. Standard tumor sampling methods make this problematic, as it is common to have a substantial proportion (typically 30-50%) of a tumor sample comprised of histologically benign tissue. This "normal" tissue could represent a source of non-random error or systematic bias in genomic classification. Methods To assess the performance characteristics of genomic classification to systematic error from normal contamination, we collected 55 tumor samples and paired tumor-adjacent normal tissue. Using genomic signatures from the tumor and paired normal, we evaluated how increasing normal contamination altered recurrence risk scores for various genomic predictors. Results Simulations of normal tissue contamination caused misclassification of tumors in all predictors evaluated, but different breast cancer predictors showed different types of vulnerability to normal tissue bias. While two predictors had unpredictable direction of bias (either higher or lower risk of relapse resulted from normal contamination), one signature showed predictable direction of normal tissue effects. Due to this predictable direction of effect, this signature (the PAM50) was adjusted for normal tissue contamination and these corrections improved sensitivity and negative predictive value. For all three assays quality control standards and/or appropriate bias adjustment strategies can be used to improve assay reliability. Conclusions Normal tissue sampled concurrently with tumor is an important source of bias in breast genomic predictors. All genomic predictors show some sensitivity to normal tissue contamination and ideal strategies for mitigating this bias vary depending upon the particular genes and computational methods used in the predictor

    Identification of Functional Networks of Estrogen- and c-Myc-Responsive Genes and Their Relationship to Response to Tamoxifen Therapy in Breast Cancer

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    BACKGROUND: Estrogen is a pivotal regulator of cell proliferation in the normal breast and breast cancer. Endocrine therapies targeting the estrogen receptor are effective in breast cancer, but their success is limited by intrinsic and acquired resistance. METHODOLOGY/PRINCIPAL FINDINGS: With the goal of gaining mechanistic insights into estrogen action and endocrine resistance, we classified estrogen-regulated genes by function, and determined the relationship between functionally-related genesets and the response to tamoxifen in breast cancer patients. Estrogen-responsive genes were identified by transcript profiling of MCF-7 breast cancer cells. Pathway analysis based on functional annotation of these estrogen-regulated genes identified gene signatures with known or predicted roles in cell cycle control, cell growth (i.e. ribosome biogenesis and protein synthesis), cell death/survival signaling and transcriptional regulation. Since inducible expression of c-Myc in antiestrogen-arrested cells can recapitulate many of the effects of estrogen on molecular endpoints related to cell cycle progression, the estrogen-regulated genes that were also targets of c-Myc were identified using cells inducibly expressing c-Myc. Selected genes classified as estrogen and c-Myc targets displayed similar levels of regulation by estrogen and c-Myc and were not estrogen-regulated in the presence of siMyc. Genes regulated by c-Myc accounted for 50% of all acutely estrogen-regulated genes but comprised 85% (110/129 genes) in the cell growth signature. siRNA-mediated inhibition of c-Myc induction impaired estrogen regulation of ribosome biogenesis and protein synthesis, consistent with the prediction that estrogen regulates cell growth principally via c-Myc. The 'cell cycle', 'cell growth' and 'cell death' gene signatures each identified patients with an attenuated response in a cohort of 246 tamoxifen-treated patients. In multivariate analysis the cell death signature was predictive independent of the cell cycle and cell growth signatures. CONCLUSIONS/SIGNIFICANCE: These functionally-based gene signatures can stratify patients treated with tamoxifen into groups with differing outcome, and potentially identify distinct mechanisms of tamoxifen resistance

    Impaired Carbohydrate Digestion and Transport and Mucosal Dysbiosis in the Intestines of Children with Autism and Gastrointestinal Disturbances

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    Gastrointestinal disturbances are commonly reported in children with autism, complicate clinical management, and may contribute to behavioral impairment. Reports of deficiencies in disaccharidase enzymatic activity and of beneficial responses to probiotic and dietary therapies led us to survey gene expression and the mucoepithelial microbiota in intestinal biopsies from children with autism and gastrointestinal disease and children with gastrointestinal disease alone. Ileal transcripts encoding disaccharidases and hexose transporters were deficient in children with autism, indicating impairment of the primary pathway for carbohydrate digestion and transport in enterocytes. Deficient expression of these enzymes and transporters was associated with expression of the intestinal transcription factor, CDX2. Metagenomic analysis of intestinal bacteria revealed compositional dysbiosis manifest as decreases in Bacteroidetes, increases in the ratio of Firmicutes to Bacteroidetes, and increases in Betaproteobacteria. Expression levels of disaccharidases and transporters were associated with the abundance of affected bacterial phylotypes. These results indicate a relationship between human intestinal gene expression and bacterial community structure and may provide insights into the pathophysiology of gastrointestinal disturbances in children with autism

    Criteria for the use of omics-based predictors in clinical trials: Explanation and elaboration

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    High-throughput 'omics' technologies that generate molecular profiles for biospecimens have been extensively used in preclinical studies to reveal molecular subtypes and elucidate the biological mechanisms of disease, and in retrospective studies on clinical specimens to develop mathematical models to predict clinical endpoints. Nevertheless, the translation of these technologies into clinical tests that are useful for guiding management decisions for patients has been relatively slow. It can be difficult to determine when the body of evidence for an omics-based test is sufficiently comprehensive and reliable to support claims that it is ready for clinical use, or even that it is ready for definitive evaluation in a clinical trial in which it may be used to direct patient therapy. Reasons for this difficulty include the exploratory and retrospective nature of many of these studies, the complexity of these assays and their application to clinical specimens, and the many potential pitfalls inherent in the development of mathematical predictor models from the very high-dimensional data generated by these omics technologies. Here we present a checklist of criteria to consider when evaluating the body of evidence supporting the clinical use of a predictor to guide patient therapy. Included are issues pertaining to specimen and assay requirements, the soundness of the process for developing predictor models, expectations regarding clinical study design and conduct, and attention to regulatory, ethical, and legal issues. The proposed checklist should serve as a useful guide to investigators preparing proposals for studies involving the use of omics-based tests. The US National Cancer Institute plans to refer to these guidelines for review of proposals for studies involving omics tests, and it is hoped that other sponsors will adopt the checklist as well. © 2013 McShane et al.; licensee BioMed Central Ltd

    Assessing HER2 amplification in breast cancer: findings from the Australian In Situ Hybridization Program

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    In August 2006, the Australian government approved subsidized trastuzumab therapy for human epidermal growth factor receptor 2 (HER2)-positive early breast cancer, and it was mandated that HER2 testing should be performed using in situ hybridization (ISH) rather than immunohistochemistry (IHC). Here we review results of the first regulated, nationwide program to provide HER2 ISH testing for all newly diagnosed breast cancer patients, with a particular emphasis on cases where IHC and ISH results were discordant. Data from all laboratories participating in the program were collated. Cases with an equivocal ISH test result [by chromogenic ISH (CISH) or silver ISH (SISH)] were tested centrally by fluorescence ISH. Most laboratories also performed HER2 IHC, and 200 cases with discordant IHC and ISH results were selected for further analysis in a central laboratory. A total of 26 laboratories were involved and 53,402 tests were reported. Over a 4-year period the HER2 positivity rate decreased for primary cancers from 23.8 to 14.6 %, but remained relatively constant for samples from metastases. Average ISH reporting times wer

    PALVELUTUOTTEEN HINNOITTELUN KEHITTÄMINEN

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    Tämän opinnäytetyön aiheena on palvelutuotteen hinnoittelun kehittäminen. Tutkimuksen kohteena on Tili- ja isännöitsijätoimisto Ky. Tili- ja isännöitsijätoimisto Ky on Vaasassa toimiva tili- ja isännöintitoimisto, joka tarjoaa taloushallinto- ja isännöintipalveluita yrityksille. Tutkimuksen tavoitteena on kehittää Tili- ja isännöitsijätoimisto Ky:n isännöitsijän palvelutuotteiden hinnoittelua. Hinnoittelumenetelmäksi valittiin toimintoperusteinen hinnoittelu, jonka lähtökohtana on selvittää asiakaskohtaisia välillisiä kustannuksia. Kysymys oli suorite-kohtaisten kustannusten laskemisesta, eli toimintoperusteisesta prosessilaskennasta. Toimintoperusteinen prosessilaskenta tukee hinnoittelun päätöstä. Toiminto-analyysin jälkeen selvitettiin resurssien kohdistumista yrityksen eri toiminnoille. Aluksi selvitettiin yrityksen kustannusajuri, jonka perusteella kustannukset on kohdistettu eri toiminnoille. Seuraavaksi selvitettiin toimintoajurin avulla toimintoihin liittyvät yksikkökustannukset. Tuotteiden hinnoittelussa myyntihinnan on tarkoituksena sisältää kaikkien kustannusten lisäksi voittotavoite. Tutkimuksen teoriaosuuden keskeisiä asioita ovat toimintoperusteisen kustannuslaskennan, sekä hinnoittelun perusteiden esittely. Niiden avulla voidaan perustella hinnoittelupäätöstä tukeva toimintolaskenta. Opinnäytetyössä esitellään lisäksi kustannusperusteista hinnoittelua sekä isännöintiä ja tilitoimistoa yleisesti. Tutkimusmenetelmänä käytettiin kvalitatiivista eli laadullista tutkimusta. Tutkimuksen teoriaosuuteen käytettiin toimintolaskennan, taloushallinnon alan sekä hinnoittelun teoriaan liittyvää kirjallisuutta. Aineistonkeruussa havainnoitiin yrityksen tilinpäätöstä vuodelta 2016 ja yrityksen toimintaa liittyviä ohjelmia sekä tietokantoja. Lisäksi haastateltiin Tili- ja isännöitsijätoimisto Ky:n omistajaa ja työntekijöitä.This research was designed to develop the used pricing method for the case firm Tili- ja isännöitsijätoimisto Ky. The main area of this research focused on the main service products in property management. The case firm offers financial accounting and management services to house companies and other customer companies. Activity based costing was selected as the new pricing method in order to identify the customer-specific indirect costs. The aim of activity-based costing was to support pricing decisions for the case firm. In the implementation steps, activities must be identified first, and then the process continues with an activity analysis. Once the costs of activity and its drivers have been identified and its costs have been determined, then the costs of activity is allocated to the service product. In the allocation process, when the activity driver has been determined, the cost per unit can then be determined. Once the product cost per unit has been determined then the case firm considers the generated value of its service product, so the pricing of all the service product sales cover the fixed expenses with any remaining contribution margin providing profits. The theoretical study of this thesis introduced activity based costing and pricing to support activity based cost implementation and pricing decisions. In addition, it introduced cost based pricing and property management business and accounting firms in general. This research was implemented using the qualitative research method. The research material consists of related activity based costing, financial management, management accounting and pricing literature. The theoretical information was gathered from scientific research, academic books and some material was collect-ed from the Internet. The empirical data in this research was gathered by observing the case company’s financial statement from the year 2016 together with some business activities related programs and databases. In addition, was collected by interviewing the case company owner and the other employers of the company
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