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1.
Biopreserv Biobank ; 17(3): 209-212, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31188626

RESUMO

Medical research advances enabling the realization of precision medicine have relied heavily on the biospecimens provided by bioresources to identify the targets and biomarkers that are the focus of the new generation of more effective molecular-based therapies for specific subtypes of diseases. Through the biospecimens they have distributed, bioresources have permitted subtypes of cancers to be identified and molecular features of these subtypes to be effectively targeted. A prototype example is the human epidermal growth factor receptor type 2 (HER2), which currently is targeted in breast and gastric cancers. In the future, the use of biospecimens from bioresources will continue to increase the understanding of the molecular actions of drugs and how drugs may be more or less active in subpopulations of patients. Although the biospecimen inventories of the initial forms of bioresources may not have always been optimally planned and, therefore, utilized in supporting biomedical research, bioresources are evolving and overall, bioresource inventories and increasingly their prospective collection capabilities will continue to be a critical component of the research infrastructure.


Assuntos
Bancos de Espécimes Biológicos , Pesquisa Biomédica , Biomarcadores/metabolismo , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia
2.
Oncotarget ; 8(5): 8226-8238, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28030809

RESUMO

Breast cancer is a heterogeneous disease comprised of four molecular subtypes defined by whether the tumor-originating cells are luminal or basal epithelial cells. Breast cancers arising from the luminal mammary duct often express estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth receptor 2 (HER2). Tumors expressing ER and/or PR are treated with anti-hormonal therapies, while tumors overexpressing HER2 are targeted with monoclonal antibodies. Immunohistochemical detection of ER, PR, and HER2 receptors/proteins is a critical step in breast cancer diagnosis and guided treatment. Breast tumors that do not express these proteins are known as "triple negative breast cancer" (TNBC) and are typically basal-like. TNBCs are the most aggressive subtype, with the highest mortality rates and no targeted therapy, so there is a pressing need to identify important TNBC tumor regulators. The signal transducer and activator of transcription 3 (STAT3) transcription factor has been previously implicated as a constitutively active oncogene in TNBC. However, its direct regulatory gene targets and tumorigenic properties have not been well characterized. By integrating RNA-seq and ChIP-seq data from 2 TNBC tumors and 5 cell lines, we discovered novel gene signatures directly regulated by STAT3 that were enriched for processes involving inflammation, immunity, and invasion in TNBC. Functional analysis revealed that STAT3 has a key role regulating invasion and metastasis, a characteristic often associated with TNBC. Our findings suggest therapies targeting STAT3 may be important for preventing TNBC metastasis.


Assuntos
Movimento Celular , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Fator de Transcrição STAT3/genética , Transcriptoma , Neoplasias de Mama Triplo Negativas/genética , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Ligação Proteica , Interferência de RNA , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Transfecção , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
3.
Biopreserv Biobank ; 14(6): 548-558, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27551929

RESUMO

Frequently investigators request that tissues be collected and processed in less than one hour following removal from a patient. Some biorepositories expend significant personnel time and other resources in trying to meet such goals; however, it is unclear whether the perceived benefits of relatively short cold ischemia times warrant these added costs. The literature of human surgical tissues prospectively exposed to cold ischemia at several time points was reviewed to compare the changes in transcripts/genes and microRNA with time of cold ischemia. Also, reports of protein changes in response to cold ischemia were correlated to changes in genes. The literature is limited; however, for most tissues, only a small proportion of transcripts/genes (<1%) changes up to 3 hours following surgery and most transcripts increase rather than decrease in less than 2 hours of cold ischemia. Biorepositories and investigators must consider the literature for evidence of significant changes in molecular results from tissues before spending significant resources on relatively rapid collection of tissues to meet cold ischemia times of less than 3 hours. Instead, those using human tissues in research must consider if the cold ischemia times affect their use in specific research; hence are these tissues "fit for purpose?"


Assuntos
Isquemia Fria/métodos , Preservação de Tecido/normas , Regulação da Expressão Gênica , Humanos , MicroRNAs/análise , RNA Mensageiro/análise , Fatores de Tempo , Preservação de Tecido/métodos
4.
Mol Oncol ; 10(8): 1169-82, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27282075

RESUMO

BACKGROUND: Pancreatic adenocarcinoma patients have low survival rates due to late-stage diagnosis and high rates of cancer recurrence even after surgical resection. It is important to understand the molecular characteristics associated with survival differences in pancreatic adenocarcinoma tumors that may inform patient care. RESULTS: RNA sequencing was performed for 51 patient tumor tissues extracted from patients undergoing surgical resection, and expression was associated with overall survival time from diagnosis. Our analysis uncovered 323 transcripts whose expression correlates with survival time in our pancreatic patient cohort. This genomic signature was validated in an independent RNA-seq dataset of 68 additional patients from the International Cancer Genome Consortium. We demonstrate that this transcriptional profile is largely independent of markers of cellular division and present a 19-transcript predictive model built from a subset of the 323 transcripts that can distinguish patients with differing survival times across both the training and validation patient cohorts. We present evidence that a subset of the survival-associated transcripts is associated with resistance to gemcitabine treatment in vitro, and reveal that reduced expression of one of the survival-associated transcripts, Angiopoietin-like 4, impairs growth of a gemcitabine-resistant pancreatic cancer cell line. CONCLUSIONS: Gene expression patterns in pancreatic adenocarcinoma tumors can distinguish patients with differing survival outcomes after undergoing surgical resection, and the survival difference could be associated with the intrinsic gemcitabine sensitivity of primary patient tumors. Thus, these transcriptional differences may impact patient care by distinguishing patients who would benefit from a non-gemcitabine based therapy.


Assuntos
Adenocarcinoma/genética , Angiopoietinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Análise de Sequência de RNA/métodos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Idoso , Proteína 4 Semelhante a Angiopoietina , Angiopoietinas/genética , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Análise de Sobrevida , Fatores de Tempo , Gencitabina , Neoplasias Pancreáticas
5.
Cancer Biomark ; 9(1-6): 531-49, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22112494

RESUMO

The availability of human tissues to support biomedical research is critical to advance translational research focused on identifying and characterizing approaches to individualized (personalized) medical care. Providing such tissues relies on three acceptable models - a tissue banking model, a prospective collection model and a combination of these two models. An unacceptable model is the "catch as catch can" model in which tissues are collected, processed and stored without goals or a plan or without standard operating procedures, i.e., portions of tissues are collected as available and processed and stored when time permits. In the tissue banking model, aliquots of tissues are collected according to SOPs. Usually specific sizes and types of tissues are collected and processed (e.g., 0.1 gm of breast cancer frozen in OCT). Using the banking model, tissues may be collected that may not be used and/or do not meet specific needs of investigators; however, at the time of an investigator request, tissues are readily available as is clinical information including clinical outcomes. In the model of prospective collection, tissues are collected based upon investigator requests including specific requirements of investigators. For example, the investigator may request that two 0.15 gm matching aliquots of breast cancer be minced while fresh, put in RPMI media with and without fetal calf serum, cooled to 4°C and shipped to the investigator on wet ice. Thus, the tissues collected prospectively meet investigator needs, all collected specimens are utilized and storage of specimens is minimized; however, investigators must wait until specimens are collected, and if needed, for clinical outcome. The operation of any tissue repository requires well trained and dedicated personnel. A quality assurance program is required which provides quality control information on the diagnosis of a specimen that is matched specifically to the specimen provided to an investigator instead of an overall diagnosis of the specimen via a surgical pathology report. This is necessary because a specific specimen may not match the diagnosis of the case due to many factors such as necrosis, unsuspected tumor invasion of apparently normal tissue, and areas of fibrosis which are mistaken grossly for tumor. Aliquots for quality control (QC) may or may not be collected at the time of collection and in some cases, QC may not occur until specimens are distributed to investigators. In establishing a tumor repository, multiple issues need to be considered. These include the available resources, long term support, space and equipment. The needs of the potential users need to be identified as to the types of tissues and services needed and the annotation expected. Other specific issues to be considered include collection of specimens potentially infected with blood borne pathogens (e.g., hepatitis B), charge back mechanisms, informatics needs and support, and investigator requirements (e.g., recognition of repository contributions in publications). In general, the repository should not perform the research of the investigators, but should provide the infrastructure necessary to support the research of the investigator. Thus, the goals of the repository must be established. Similarly, ethical and regulatory issues must be evaluated. In general, tissue repositories need ethical (e.g., IRB) and privacy (e.g., HIPAA) review. Also, safety issues need to be considered as well as how biohazards will be addressed by investigator-users. Considerations involving the transfer of specimens to other organization usually require a material transfer agreement (MTA). A MTA should address biohazards as well as indemnification. Thus, many issues must be considered and addressed in order to establish and operate successfully a biorepository.


Assuntos
Pesquisa Biomédica , Informática , Bancos de Tecidos , Humanos , Controle de Qualidade , Manejo de Espécimes , Bancos de Tecidos/ética , Bancos de Tecidos/legislação & jurisprudência
6.
Methods Mol Biol ; 576: 1-30, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19882254

RESUMO

Superior-quality human tissues are required to support many types of biomedical research. To be useful optimally in supporting research, not only must these tissues be accurately diagnosed, but also the specific aliquots of tissue supplied to investigators must be accurately described as part of the quality control analysis of the tissue. Tissues should be collected, processed, and stored uniformly. Some tissues are provided to investigators from tissue banks for which tissues have been collected and processed according to standard operating procedures (SOPs) of the tissue bank. Other tissues provided to support research are collected and processed according to SOPs modified to meet investigator needs and requirements, i.e., prospective collection/processing. These different models of tissue collection require different goals, designs, and SOPs. The objectives of tissue repositories also vary based on the types of tissues provided (e.g., fresh tissue aliquots, fixed paraffin-embedded tissue, paraffin tissue sections, etc.) and how the tissues are to be used in research. For example, the potential use of tissues affects the need for extensive annotation of the specimen including both clinical information (e.g., clinical outcomes) and demographics. Specifically, if the tissues are to be used for extraction of proteins or basic studies of disease processes, less clinical information, if any, may be needed than if the tissues are to be used for the correlation of an aspect of the disease process with clinical outcome or response to a specific therapy. In this review, we describe, based on our experience, the major issues that should be addressed in designing and establishing a tissue repository.


Assuntos
Pesquisa Biomédica/organização & administração , Obtenção de Tecidos e Órgãos/organização & administração , Pesquisa Biomédica/ética , Humanos , Neoplasias/patologia , Controle de Qualidade , Manejo de Espécimes/métodos , Fatores de Tempo , Bancos de Tecidos/ética , Bancos de Tecidos/organização & administração , Obtenção de Tecidos e Órgãos/ética
7.
Cancer Epidemiol Biomarkers Prev ; 18(6): 1676-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19435863

RESUMO

The purpose of this article is to facilitate access of biomedical researchers to human tissues by describing the types of tissue resources available to researchers, common problems with tissue requests that may limit tissue availability to specific investigators, and steps that can be taken to simplify requests to avoid these problems and enhance access to tissue. Types of human tissue resources available to investigators are described and reviewed, and the experience of the University of Alabama Tissue Collection and Banking Facility (TCBF) is described. Our experience indicates that typical problems with requests for tissue fall into the following categories: (1) size and number of specimens, (2) type (rarity and availability), (3) time constraints, (4) demand versus supply, (5) limitations and goals of the resource, and (6) time and resources that can be devoted to a specific request. Investigators should review their requests for human tissues to support their research if they are not receiving adequate quantities of tissue. This review is best accomplished by discussing their requests with the tissue resource and correcting specific limitations that block access to the tissues they need.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Pesquisa Biomédica , Obtenção de Tecidos e Órgãos , Bancos de Espécimes Biológicos/ética , Pesquisa Biomédica/ética , Humanos , Manejo de Espécimes , Obtenção de Tecidos e Órgãos/ética
8.
Cancer Epidemiol Biomarkers Prev ; 12(2): 114-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12582020

RESUMO

9-Cis-retinoic acid (aliretinoin) is a pan-retinoid receptor agonist and has been demonstrated in preclinical models to have potent chemoprevention effects. The purpose of this study was to determine the utility of using aliretinoin as a chemoprevention agent in cervical dysplasia. Patients with histological evidence of cervical intraepithelial neoplasia (CIN) 2/3 were randomized in a double-blind manner to receive high-dose aliretinoin (50 mg), low-dose of aliretinoin (25 mg), or placebo daily for 12 weeks. Compliance and side effects were monitored at various time points during therapy. At the completion of therapy, all of the patients underwent a loop procedure. Histology of pretreatment biopsies was compared with that of loop specimens. One-hundred and fourteen patients with CIN 2/3 were enrolled in the study. In the 112 patients evaluable for toxicity, headache was the most common clinical side effect and was experienced more frequently (74%) in the high-dose aliretinoin group. Eight patients withdrew from the study before completion of study medication because of unacceptable side effects. In the 104 patients evaluable for efficacy, there was no statistical difference in the rate of regression among the placebo (32%), the low-dose aliretinoin (32%), and the high-dose aliretinoin (36%) groups. (P = not significant; power 0.06). Aliretinoin at these dosages and this schedule does not appear to result in significant regression rates in CIN 2/3 patients when compared with placebo. Headache is encountered frequently and may thwart efforts to increase the dose or duration of aliretinoin in future cervical cancer chemoprevention studies. The rate of histological regression in biopsied CIN 2/3 patients is high even over a short time interval, and emphasizes the importance of having a placebo arm and an adequate sample size in cervical dysplasia chemoprevention studies.


Assuntos
Antineoplásicos/uso terapêutico , Quimioprevenção , Tretinoína/uso terapêutico , Displasia do Colo do Útero/prevenção & controle , Adolescente , Adulto , Alabama , Alitretinoína , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Biomarcadores/sangue , HDL-Colesterol/sangue , HDL-Colesterol/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Avaliação de Medicamentos , Feminino , Hemoglobinas/efeitos dos fármacos , Humanos , Cooperação do Paciente , Índice de Gravidade de Doença , Resultado do Tratamento , Tretinoína/administração & dosagem , Tretinoína/efeitos adversos , Triglicerídeos/sangue , Displasia do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Saúde da Mulher
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