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1.
Cancers (Basel) ; 14(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36230537

RESUMO

Hyaluronic acid (HA) is highly elevated in breast cancers compared to normal breast tissue and is associated with increased tumor aggressiveness and poor prognosis. HA interacts with cell-trafficking CD44 receptors to promote tumor cell migration and proliferation and regulates both pro- and anti-inflammatory cytokine production through tumor-associated macrophages. The highly negative charge of HA enables its uptake of vast amounts of water that greatly increases the tumor interstitial fluidic pressure, which, combined with the presence of other extracellular matrix components such as collagen, results in tumor stroma with abnormal vasculature, hypoxia, and increased drug resistance. Thus, the degradation of HA in breast cancer may attenuate growth and improve permeability to anticancer agents. Previous methods to deplete tumor HA have resulted in significant off-tumor effects due to the systemic use of mammalian hyaluronidases. To overcome this, we developed a hyaluronidase-secreting Salmonella typhimurium (YS-HAse) that specifically and preferentially colonizes tumors to deplete HA. We show that the systemic administration of YS-HAse in immunocompetent murine models of breast cancer enhances tumor perfusion, controls tumor growth, and restructures the tumor immune contexture. These studies highlight the utility of YS-HAse as a novel microbial-based therapeutic that may also be combined with existing therapeutic approaches.

2.
Bioanalysis ; 13(5): 295-361, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33511867

RESUMO

The 14th edition of the Workshop on Recent Issues in Bioanalysis (14th WRIB) was held virtually on June 15-29, 2020 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. The 14th WRIB included three Main Workshops, seven Specialized Workshops that together spanned 11 days in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy and vaccine. Moreover, a comprehensive vaccine assays track; an enhanced cytometry track and updated Industry/Regulators consensus on BMV of biotherapeutics by LCMS were special features in 2020. As in previous years, this year's WRIB continued to gather a wide diversity of international industry opinion leaders and regulatory authority experts working on both small and large molecules to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance and achieving scientific excellence on bioanalytical issues. This 2020 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the Global Bioanalytical Community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2020 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication covers the recommendations on (Part 2A) BAV, PK LBA, Flow Cytometry Validation and Cytometry Innovation and (Part 2B) Regulatory Input. Part 1 (Innovation in Small Molecules, Hybrid LBA/LCMS & Regulated Bioanalysis), Part 3 (Vaccine, Gene/Cell Therapy, NAb Harmonization and Immunogenicity) are published in volume 13 of Bioanalysis, issues 4, and 6 (2021), respectively.


Assuntos
Bioensaio , Biotecnologia , Terapia Baseada em Transplante de Células e Tecidos , Terapia Genética , Relatório de Pesquisa , Biomarcadores/análise , Humanos
3.
Bioanalysis ; 11(23): 2099-2132, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31833782

RESUMO

The 2019 13th Workshop on Recent Issues in Bioanalysis (WRIB) took place in New Orleans, LA on 1-5 April 2019 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day, week-long event - a full immersion week of bioanalysis, biomarkers, immunogenicity and gene therapy. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule bioanalysis involving LCMS, hybrid LBA/LCMS, LBA cell-based/flow cytometry assays and qPCR approaches. This 2019 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2019 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on the 2018 FDA BMV guidance, 2019 ICH M10 BMV draft guideline and regulatory agencies' input on bioanalysis, biomarkers, immunogenicity and gene therapy. Part 1 (Innovation in small molecules and oligonucleotides and mass spectrometry method development strategies for large molecules bioanalysis) and Part 3 (New insights in biomarker assay validation, current and effective strategies for critical reagent management, flow cytometry validation in drug discovery and development and CLSI H62, interpretation of the 2019 FDA immunogenicity guidance and gene therapy bioanalytical challenges) are published in volume 10 of Bioanalysis, issues 22 and 24 (2019), respectively.


Assuntos
Bioensaio/normas , Biomarcadores/análise , Guias como Assunto , Fenômenos Imunogenéticos , Relatório de Pesquisa , United States Food and Drug Administration/legislação & jurisprudência , Humanos , Estados Unidos
4.
Anal Bioanal Chem ; 381(7): 1460-6, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15798905

RESUMO

A simple, fast method is described for the determination of Ag, As, Cd, Cu, Cr, Fe, Ni, and Se in marine biological tissues by electrothermal atomic-absorption spectrometry (ETAAS) and Na, Ca, K, Mg, Fe, Cu, and Mn by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Solubilization of the biological tissue was achieved by using formic acid with vortex mixing followed by heating to 50 degrees C in an ultrasonic bath. Once solubilized, the tissues were diluted to an appropriate volume with water for analysis. Aliquots were sampled into a graphite furnace and ICP-AES using a conventional autosampler. The method was validated by use of biological certified reference materials from NRC, DORM-2, DOLT-2, DOLT-3, LUTS-1, TORT-2, and NIST SRMs 1566b and 2976. Simplicity and reduced sample-preparation time prove to be the major advantages to the technique.


Assuntos
Técnicas de Química Analítica/métodos , Formiatos/química , Oligoelementos/análise , Animais , Reprodutibilidade dos Testes , Espectrofotometria Atômica/métodos
5.
J Natl Cancer Inst ; 96(10): 796-800, 2004 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-15150308

RESUMO

Vitamin E in foodstuffs is a mixture of tocopherols. In mouse Mutatect tumors, a model designed to detect DNA mutations, the hypoxanthine phosphoribosyltransferase (Hprt) gene mutation frequency is associated with the number of tumor-infiltrating neutrophils and both are markedly decreased in mice fed high levels of alpha-tocopherol. Dietary alpha-tocopherol is also associated with a decrease in neutrophil-associated loss of an interleukin 8 (IL-8)-expressing transgene in this tumor model. We examined Hprt gene mutation frequency (expressed as the number of 6-thioguanine-resistant colonies per 10(5) clonable tumor cells), IL-8 transgene loss, and myeloperoxidase activity (an indirect measure of neutrophil number) in tumors from Mutatect mice fed diets supplemented with various concentrations of D-alpha-tocopherol acetate and/or D-gamma-tocopherol acetate or neither tocopherol for 4 weeks. Hprt gene mutation frequency and myeloperoxidase activity were statistically significantly lower in tumor cells from mice fed alpha-tocopherol at 50 or 100 mg/kg body weight per day than in tumor cells from mice fed 0 mg/kg body weight per day alpha-tocopherol (P<.001 for each comparison). IL-8 transgene loss occurred in 28 of 28 tumors (100%; 95% confidence interval [CI] = 86% to 100%) from mice fed alpha-tocopherol at 50 mg or less/kg body weight per day and seven of 18 tumors (39%; 95% CI = 24% to 54%) from mice fed 100 mg/kg body weight per day (P<.001, Fisher's exact test, referent groups [pooled] 0, 25, and 50 mg/kg). gamma-Tocopherol had no detectable effect on any of the three endpoints. Thus, dietary alpha-tocopherol decreases two forms of genetic instability in a dose-dependent manner in this experimental tumor model.


Assuntos
Suplementos Nutricionais , Fibrossarcoma/tratamento farmacológico , Interleucina-8/genética , Neoplasias Experimentais/tratamento farmacológico , Vitamina E/administração & dosagem , Vitamina E/farmacologia , Análise de Variância , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fibrossarcoma/sangue , Fibrossarcoma/genética , Hipoxantina Fosforribosiltransferase/genética , Camundongos , Mutação , Transplante de Neoplasias , Neoplasias Experimentais/sangue , Neoplasias Experimentais/genética , Peroxidase/metabolismo , Transgenes , Vitamina E/sangue , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/farmacologia , gama-Tocoferol/administração & dosagem , gama-Tocoferol/farmacologia
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