RESUMO
There has been increasing evidence in recent years that research in life sciences is lacking in reproducibility and data quality. This raises the need for effective systems to improve data integrity in the evolving non-GxP research environment. This chapter describes the critical elements that need to be considered to ensure a successful implementation of research quality standards in both industry and academia. The quality standard proposed is founded on data integrity principles and good research practices and contains basic quality system elements, which are common to most laboratories. Here, we propose a pragmatic and risk-based quality system and associated assessment process to ensure reproducibility and data quality of experimental results while making best use of the resources.
Assuntos
Disciplinas das Ciências Biológicas/educação , Reprodutibilidade dos Testes , Pesquisa/normas , Pesquisa Biomédica/educaçãoRESUMO
CONTEXT: Correct gender assignment in humans at the molecular level is crucial in many scientific disciplines and applied areas. MATERIALS AND METHODS: Candidate gender markers were identified through supervised statistical analysis of genome wide microarray expression data from human blood samples (N = 123, 58 female, 65 male) as a training set. The potential of the markers to predict undisclosed tissue donor gender was tested on microarray data from 13 healthy and 11 cancerous human tissue collections (internal) and external datasets from samples of varying tissue origin. The abundance of some genes in the marker panel was quantified by RT-PCR as alternative analytical technology. RESULTS: We identified and qualified predictive, gender-specific transcript markers based on a set of five genes (RPS4Y1, EIF1AY, DDX3Y, KDM5D and XIST). CONCLUSION: Gene expression marker panels can be used as a robust tissue- and platform-independent predictive approach for gender determination.
Assuntos
Perfilação da Expressão Gênica , RNA Mensageiro/sangue , Análise para Determinação do Sexo/métodos , Biomarcadores/sangue , RNA Helicases DEAD-box/sangue , RNA Helicases DEAD-box/genética , Feminino , Histona Desmetilases/sangue , Histona Desmetilases/genética , Humanos , Masculino , Antígenos de Histocompatibilidade Menor , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos , RNA Longo não Codificante/sangue , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Proteínas Ribossômicas/sangue , Proteínas Ribossômicas/genética , TranscriptomaRESUMO
While high risk of failure is an inherent part of developing innovative therapies, it can be reduced by adherence to evidence-based rigorous research practices. Supported through the European Union's Innovative Medicines Initiative, the EQIPD consortium has developed a novel preclinical research quality system that can be applied in both public and private sectors and is free for anyone to use. The EQIPD Quality System was designed to be suited to boost innovation by ensuring the generation of robust and reliable preclinical data while being lean, effective and not becoming a burden that could negatively impact the freedom to explore scientific questions. EQIPD defines research quality as the extent to which research data are fit for their intended use. Fitness, in this context, is defined by the stakeholders, who are the scientists directly involved in the research, but also their funders, sponsors, publishers, research tool manufacturers, and collaboration partners such as peers in a multi-site research project. The essence of the EQIPD Quality System is the set of 18 core requirements that can be addressed flexibly, according to user-specific needs and following a user-defined trajectory. The EQIPD Quality System proposes guidance on expectations for quality-related measures, defines criteria for adequate processes (i.e. performance standards) and provides examples of how such measures can be developed and implemented. However, it does not prescribe any pre-determined solutions. EQIPD has also developed tools (for optional use) to support users in implementing the system and assessment services for those research units that successfully implement the quality system and seek formal accreditation. Building upon the feedback from users and continuous improvement, a sustainable EQIPD Quality System will ultimately serve the entire community of scientists conducting non-regulated preclinical research, by helping them generate reliable data that are fit for their intended use.
Assuntos
Pesquisa Biomédica/normas , Avaliação Pré-Clínica de Medicamentos/normas , Projetos de Pesquisa/normas , Comportamento Cooperativo , Confiabilidade dos Dados , Difusão de Inovações , Europa (Continente) , Humanos , Comunicação Interdisciplinar , Controle de Qualidade , Melhoria de Qualidade , Participação dos InteressadosRESUMO
External access to scientific technology plays an increasingly important part in pharmaceutical R&D. One advantage of accessing technology externally is the avoidance of costs associated with purchase and the reduced time required for developing new methods; in addition, access to external scientific expertise can be beneficial. However, few conceptual frameworks exist for achieving an optimal mix of internal and external technology access. In this review, we describe the virtuous technology cycle (VTC) concept and exemplify its application to next-generation sequencing (NGS). Based on selected examples, we show that the VTC concept can greatly enhance the number of technologies accessed and thus significantly increase flexibility and efficiency in drug discovery. We also discuss the challenges of externally accessing NGS technologies.
Assuntos
Descoberta de Drogas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Tecnologia FarmacêuticaRESUMO
Anti-cancer therapy based on anthracyclines (DNA intercalating Topoisomerase II inhibitors) is limited by adverse effects of these compounds on the cardiovascular system, ultimately causing heart failure. Despite extensive investigations into the effects of doxorubicin on the cardiovascular system, the molecular mechanisms of toxicity remain largely unknown. MicroRNAs are endogenously transcribed non-coding 22 nucleotide long RNAs that regulate gene expression by decreasing mRNA stability and translation and play key roles in cardiac physiology and pathologies. Increasing doses of doxorubicin, but not etoposide (a Topoisomerase II inhibitor devoid of cardiovascular toxicity), specifically induced the up-regulation of miR-208b, miR-216b, miR-215, miR-34c and miR-367 in rat hearts. Furthermore, the lowest dosing regime (1 mg/kg/week for 2 weeks) led to a detectable increase of miR-216b in the absence of histopathological findings or alteration of classical cardiac stress biomarkers. In silico microRNA target predictions suggested that a number of doxorubicin-responsive microRNAs may regulate mRNAs involved in cardiac tissue remodeling. In particular miR-34c was able to mediate the DOX-induced changes of Sipa1 mRNA (a mitogen-induced Rap/Ran GTPase activating protein) at the post-transcriptional level and in a seed sequence dependent manner. Our results show that integrated heart tissue microRNA and mRNA profiling can provide valuable early genomic biomarkers of drug-induced cardiac injury as well as novel mechanistic insight into the underlying molecular pathways.
Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , MicroRNAs/genética , Miocárdio/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Biomarcadores/metabolismo , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/metabolismo , Doxorrubicina/farmacologia , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Células HEK293 , Humanos , Masculino , MicroRNAs/metabolismo , Proteínas Musculares/metabolismo , Miocárdio/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ativação Transcricional/efeitos dos fármacos , Transcriptoma , Regulação para Cima/efeitos dos fármacos , Vacúolos/efeitos dos fármacosRESUMO
Large-scale molecular profiling technologies have assisted the identification of disease biomarkers and facilitated the basic understanding of cellular processes. However, samples collected from human subjects in clinical trials possess a level of complexity, arising from multiple cell types, that can obfuscate the analysis of data derived from them. Failure to identify, quantify, and incorporate sources of heterogeneity into an analysis can have widespread and detrimental effects on subsequent statistical studies.We describe an approach that builds upon a linear latent variable model, in which expression levels from mixed cell populations are modeled as the weighted average of expression from different cell types. We solve these equations using quadratic programming, which efficiently identifies the globally optimal solution while preserving non-negativity of the fraction of the cells. We applied our method to various existing platforms to estimate proportions of different pure cell or tissue types and gene expression profilings of distinct phenotypes, with a focus on complex samples collected in clinical trials. We tested our methods on several well controlled benchmark data sets with known mixing fractions of pure cell or tissue types and mRNA expression profiling data from samples collected in a clinical trial. Accurate agreement between predicted and actual mixing fractions was observed. In addition, our method was able to predict mixing fractions for more than ten species of circulating cells and to provide accurate estimates for relatively rare cell types (<10% total population). Furthermore, accurate changes in leukocyte trafficking associated with Fingolomid (FTY720) treatment were identified that were consistent with previous results generated by both cell counts and flow cytometry. These data suggest that our method can solve one of the open questions regarding the analysis of complex transcriptional data: namely, how to identify the optimal mixing fractions in a given experiment.
Assuntos
Algoritmos , Sangue/metabolismo , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Transcrição Gênica/genética , Adulto , Linhagem Celular , Feminino , Humanos , Análise dos Mínimos Quadrados , Modelos Lineares , RNA Mensageiro/sangue , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Cytokines macrophage colony stimulating factor (M-CSF) and the receptor activator of NFkappaB ligand (RANKL) induce differentiation of bone marrow hematopoietic precursor cells into bone-resorbing osteoclasts without the requirement for stromal cells of mesenchymal origin. We used this recently described mouse cell system and oligonucleotide microarrays representing about 9,400 different genes to analyze gene expression in hematopoietic cells undergoing differentiation to osteoclasts. The ability of microarrays to detect the genes of interest was validated by showing expression and expected regulation of several osteoclast marker genes. In total 750 known transcripts were up-regulated by > or =2-fold, and 91% of them at an early time in culture, suggesting that almost the whole differentiation program is defined already in pre-osteoclasts. As expected, M-CSF alone induced the receptor for RANKL (RANK), but also, unexpectedly, other RANK/NFkappaB pathway components (TRAF2A, PI3-kinase, MEKK3, RIPK1), providing a molecular explanation for the synergy of M-CSF and RANKL. Furthermore, interleukins, interferons, and their receptors (IL-1alpha, IL-18, IFN-beta, IL-11Ralpha2, IL-6/11R gp130, IFNgammaR) were induced by M-CSF. Although interleukins are thought to regulate osteoclasts via modulation of M-CSF and RANKL expression in stromal cells, we showed that a mix of IL-1, IL-6, and IL-11 directly increased the activity of osteoclasts by 8.5-fold. RANKL induced about 70 novel target genes, including chemokines and growth factors (RANTES (regulated on activation, normal T cell expressed and secreted), PDGFalpha, IGF1), histamine, and alpha1A-adrenergic receptors, and three waves of distinct receptors, transcription factors, and signaling molecules. In conclusion, M-CSF induced genes necessary for a direct response to RANKL and interleukins, while RANKL directed a three-stage differentiation program and induced genes for interaction with osteoblasts and immune and nerve cells. Thus, global gene expression suggests a more dynamic role of osteoclasts in bone physiology than previously anticipated.