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1.
Methods Mol Biol ; 1897: 7-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30539430

RESUMO

The purpose of a biobank is to process, organize, and maintain various types of biospecimens that are to be utilized for both clinical and research-based services. There are different types of biobanks, so the goals of the biobank should be delineated at the outset of forming a biobank. The startup of a biobank benefits from accreditation and stringent adherence to standards of practice. Fundamental to these practices is the protection of privacy and informed consent. A budget must be developed, and sources of funding should be obtained to properly equip the designated space and personnel. The appropriate space for freezers and for biospecimen processing should be identified. Information technology is also a critical part of the biobank and effort should be expended to ensure that this aspect is effective and secure. Given the ethical concerns surrounding biospecimens, engagement with the public is also highly valuable.


Assuntos
Bancos de Espécimes Biológicos/tendências , Pesquisa Biomédica , Tecnologia da Informação/tendências , Humanos , Consentimento Livre e Esclarecido , Manejo de Espécimes
2.
Exp Mol Pathol ; 103(1): 87-93, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28663030

RESUMO

BACKGROUND: Commercial targeted genomic profiling with next generation sequencing using formalin-fixed paraffin embedded (FFPE) tissue has recently entered into clinical use for diagnosis and for the guiding of therapy. However, there is limited independent data regarding the accuracy or robustness of commercial genomic profiling in gliomas. METHODS: As part of patient care, FFPE samples of gliomas from 71 patients were submitted for targeted genomic profiling to one commonly used commercial vendor, Foundation Medicine. Genomic alterations were determined for the following grades or groups of gliomas; Grade I/II, Grade III, primary glioblastomas (GBMs), recurrent primary GBMs, and secondary GBMs. In addition, FFPE samples from the same patients were independently assessed with conventional methods such as immunohistochemistry (IHC), Quantitative real-time PCR (qRT-PCR), or Fluorescence in situ hybridization (FISH) for three genetic alterations: IDH1 mutations, EGFR amplification, and EGFRvIII expression. RESULTS: A total of 100 altered genes were detected by the aforementioned targeted genomic profiling assay. The number of different genomic alterations was significantly different between the five groups of gliomas and consistent with the literature. CDKN2A/B, TP53, and TERT were the most common genomic alterations seen in primary GBMs, whereas IDH1, TP53, and PIK3CA were the most common in secondary GBMs. Targeted genomic profiling demonstrated 92.3%-100% concordance with conventional methods. The targeted genomic profiling report provided an average of 5.5 drugs, and listed an average of 8.4 clinical trials for the 71 glioma patients studied but only a third of the trials were appropriate for glioma patients. CONCLUSIONS: In this limited comparison study, this commercial next generation sequencing based-targeted genomic profiling showed a high concordance rate with conventional methods for the 3 genetic alterations and identified mutations expected for the type of glioma. While it may not be feasible to exhaustively independently validate a commercial genomic profiling assay, examination of a few markers provides some reassurance of its robustness. While potential targeted drugs are recommended based on genetic alterations, to date most targeted therapies have failed in glioblasomas so the usefulness of such recommendations will increase with development of novel and efficacious drugs.


Assuntos
Formaldeído/química , Perfilação da Expressão Gênica , Genômica , Glioma/diagnóstico , Parafina/química , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Classe I de Fosfatidilinositol 3-Quinases , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Glioma/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
3.
J Neurooncol ; 132(2): 351-358, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28161760

RESUMO

Latino Americans are a rapidly growing ethnic group in the United States but studies of glioblastoma in this population are limited. We have evaluated characteristics of 21,184 glioblastoma patients from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. This SEER data from 2001 to 2011 draws from 28% of the U.S. POPULATION: Latinos have a lower incidence of GBM and present slightly younger than non-Latino Whites. Cubans present at an older age than other Latino sub-populations. Latinos have a higher incidence of giant cell glioblastoma than non-Latino Whites while the incidence of gliosarcoma is similar. Despite lower rates of radiation therapy and greater rates of sub-total resection than non-Latino Whites, Latinos have better 1 and 5 year survival rates. SEER does not record chemotherapy data. Survivals of Latino sub-populations are similar with each other. Age, extent of resection, and the use of radiation therapy are associated with improved survival but none of these variables are sufficient in a multivariate analysis to explain the improved survival of Latinos relative to non-Latino Whites. As molecular data is not available in SEER records, we studied the MGMT and IDH status of 571 patients from a UCLA database. MGMT methylation and IDH1 mutation rates are not statistically significantly different between non-Latino Whites and Latinos. For UCLA patients with available information, chemotherapy and radiation rates are similar for non-Latino White and Latino patients, but the latter have lower rates of gross total resection and present at a younger age.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Idoso , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Estudos de Coortes , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Conjuntos de Dados como Assunto/estatística & dados numéricos , Feminino , Glioblastoma/epidemiologia , Glioblastoma/genética , Glioblastoma/mortalidade , Glioblastoma/patologia , Hispânico ou Latino , Humanos , Incidência , Isocitrato Desidrogenase/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Análise de Sobrevida , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Estados Unidos/epidemiologia
4.
PLoS One ; 10(10): e0141334, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26506620

RESUMO

Glioblastoma stem cells (GSC) co-exhibiting a tumor-initiating capacity and a radio-chemoresistant phenotype, are a compelling cell model for explaining tumor recurrence. We have previously characterized patient-derived, treatment-resistant GSC clones (TRGC) that survived radiochemotherapy. Compared to glucose-dependent, treatment-sensitive GSC clones (TSGC), TRGC exhibited reduced glucose dependence that favor the fatty acid oxidation pathway as their energy source. Using comparative genome-wide transcriptome analysis, a series of defense signatures associated with TRGC survival were identified and verified by siRNA-based gene knockdown experiments that led to loss of cell integrity. In this study, we investigate the prognostic value of defense signatures in glioblastoma (GBM) patients using gene expression analysis with Probeset Analyzer (131 GBM) and The Cancer Genome Atlas (TCGA) data, and protein expression with a tissue microarray (50 GBM), yielding the first TRGC-derived prognostic biomarkers for GBM patients. Ribosomal protein S11 (RPS11), RPS20, individually and together, consistently predicted poor survival of newly diagnosed primary GBM tumors when overexpressed at the RNA or protein level [RPS11: Hazard Ratio (HR) = 11.5, p<0.001; RPS20: HR = 4.5, p = 0.03; RPS11+RPS20: HR = 17.99, p = 0.001]. The prognostic significance of RPS11 and RPS20 was further supported by whole tissue section RPS11 immunostaining (27 GBM; HR = 4.05, p = 0.01) and TCGA gene expression data (578 primary GBM; RPS11: HR = 1.19, p = 0.06; RPS20: HR = 1.25, p = 0.02; RPS11+RPS20: HR = 1.43, p = 0.01). Moreover, tumors that exhibited unmethylated O-6-methylguanine-DNA methyltransferase (MGMT) or wild-type isocitrate dehydrogenase 1 (IDH1) were associated with higher RPS11 expression levels [corr (IDH1, RPS11) = 0.64, p = 0.03); [corr (MGMT, RPS11) = 0.52, p = 0.04]. These data indicate that increased expression of RPS11 and RPS20 predicts shorter patient survival. The study also suggests that TRGC are clinically relevant cells that represent resistant tumorigenic clones from patient tumors and that their properties, at least in part, are reflected in poor-prognosis GBM. The screening of TRGC signatures may represent a novel alternative strategy for identifying new prognostic biomarkers.


Assuntos
Biomarcadores Tumorais/biossíntese , Glioblastoma/genética , Proteínas Ribossômicas/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Metilação de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fenótipo , Prognóstico , Proteínas Ribossômicas/genética , Análise Serial de Tecidos
5.
Clin Biochem ; 47(4-5): 258-66, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24424103

RESUMO

Well preserved frozen biospecimens are ideal for evaluating the genome, transcriptome, and proteome. While papers reviewing individual aspects of frozen biospecimens are available, we present a current overview of experimental data regarding procurement, storage, and quality assurance that can inform the handling of frozen biospecimens. Frozen biospecimen degradation can be influenced by factors independent of the collection methodology including tissue type, premortem agonal changes, and warm ischemia time during surgery. Rapid stabilization of tissues by snap freezing immediately can mitigate artifactually altered gene expression and, less appreciated, protein phosphorylation profiles. Collection protocols may be adjusted for specific tissue types as cellular ischemia tolerance varies widely. If data is not available for a particular tissue type, a practical goal is snap freezing within 20min. Tolerance for freeze-thaw events is also tissue type dependent. Tissue storage at -80°C can preserve DNA and protein for years but RNA can show degradation at 5years. For -80°C freezers, aliquots frozen in RNAlater or similar RNA stabilizing solutions are a consideration. It remains unresolved as to whether storage at -150°C provides significant advantages relative to that at -80°C. Histologic quality assurance of tissue biospecimens is typically performed at the time of surgery but should also be conducted on the aliquot to be distributed because of tissue heterogeneity. Biobanking protocols for blood and its components are highly dependent on intended use and multiple collection tube types may be needed. Additional quality assurance testing should be dictated by the anticipated downstream applications.


Assuntos
Artefatos , Bancos de Espécimes Biológicos/organização & administração , Criopreservação/métodos , Manejo de Espécimes/normas , Criopreservação/economia , Criopreservação/instrumentação , Congelamento , Guias como Assunto , Humanos , Estabilidade Proteica , Controle de Qualidade , Estabilidade de RNA , Manejo de Espécimes/economia , Fatores de Tempo
6.
Clin Biochem ; 47(4-5): 267-73, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24362270

RESUMO

UNLABELLED: Frozen biospecimens are crucial for translational research and contain well-preserved nucleic acids and protein. However, the risks of freezer failure as well as space, cost, and environmental concerns of frozen biospecimens are substantial. OBJECTIVE: The purpose of the study was to review the current status of room temperature biospecimen storage. METHODS: We searched Pubmed and vendor websites to identify relevant information. RESULTS: Formalin-fixed paraffin embedded (FFPE) tissues have great value but their use is limited by cross-linking and fragmentation of nucleic acids, as well as loss of enzymatic activity. Stabilization solutions can now robustly preserve fresh tissue for up to 7days at room temperature. For longer term storage, commercial vendors of chemical matrices claim real time stability of nucleic acids of over 2 years and their accelerated aging studies to date suggest stability for 12years for RNA and 60years for DNA. However, anatomic pathology biorepositories store mostly frozen tissue rather than nucleic acids. Small quantities of tissue can be directly placed on some chemical matrices to stabilize DNA, however RNA and proteins are not preserved. Current lyophilization approaches can preserve histomorphology, DNA, RNA, and proteins though RNA shows moderate degradation after 1-2years. Formalin-free fixatives show improved but varying abilities to preserve nucleic acids and face validation as well as cost barriers in replacing FFPE specimens. The paraffin embedding process can degrade RNA. CONCLUSION: Development of robust long-term room temperature biospecimen tissue storage technology can potentially reduce costs for the biomedical community in the face of growing targeted therapy needs and decreasing budgets.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Pesquisa Biomédica/organização & administração , Manejo de Espécimes/normas , Preservação de Tecido/métodos , Fixadores/química , Liofilização , Humanos , Inclusão em Parafina , Estabilidade Proteica , Controle de Qualidade , Estabilidade de RNA , Manejo de Espécimes/economia , Manejo de Espécimes/métodos , Temperatura , Fatores de Tempo , Preservação de Tecido/economia , Preservação de Tecido/instrumentação
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