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2.
NPJ Breast Cancer ; 7(1): 85, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215753

RESUMO

Management of breast cancer in limited-resource settings is hindered by a lack of low-cost, logistically sustainable approaches toward molecular and cellular diagnostic pathology services that are needed to guide therapy. To address these limitations, we have developed a multimodal cellphone-based platform-the EpiView-D4-that can evaluate both cellular morphology and molecular expression of clinically relevant biomarkers directly from fine-needle aspiration (FNA) of breast tissue specimens within 1 h. The EpiView-D4 is comprised of two components: (1) an immunodiagnostic chip built upon a "non-fouling" polymer brush-coating (the "D4") which quantifies expression of protein biomarkers directly from crude cell lysates, and (2) a custom cellphone-based optical microscope ("EpiView") designed for imaging cytology preparations and D4 assay readout. As a proof-of-concept, we used the EpiView-D4 for assessment of human epidermal growth factor receptor-2 (HER2) expression and validated the performance using cancer cell lines, animal models, and human tissue specimens. We found that FNA cytology specimens (prepared in less than 5 min with rapid staining kits) imaged by the EpiView-D4 were adequate for assessment of lesional cellularity and tumor content. We also found our device could reliably distinguish between HER2 expression levels across multiple different cell lines and animal xenografts. In a pilot study with human tissue (n = 19), we were able to accurately categorize HER2-negative and HER2-positve tumors from FNA specimens. Taken together, the EpiView-D4 offers a promising alternative to invasive-and often unavailable-pathology services and may enable the democratization of effective breast cancer management in limited-resource settings.

3.
J Law Health ; 29(2): 192-220, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30889327

RESUMO

There are many barriers to healthcare for the general population that has been documented throughout the years, with one particularly affected group being individuals with disabilities. One identified healthcare barrier for individuals with disabilities is the inability to gain access to the healthcare system through health insurance. While many attempts have been made to resolve this issue, serious problems have yet to be resolved. The Patient Protection Affordable Care Act (PPACA) attempted to solve the issue by expanding Health Insurance Portability and Accountability Act of 1996's (HIPAA) current regulations on employee wellness programs. The relevant regulations govern employee wellness programs to allow employers to offer their employees greater incentives for meeting employer-defined health targets. This expansion has an adverse effect because it disadvantages groups like individuals with disabilities by penalizing them through higher premiums or cost sharing when they are unable to meet wellness targets. This article argues PPACA's requirement for employee wellness programs provides additional barriers to healthcare insurance for individuals with disabilities. Part I of this Comment describes how the healthcare industry discriminates against individuals with disabilities by continuing to deny them meaningful access to healthcare through payment of higher premiums. Part II examines how the wellness program provision allows employers to shift the cost of medical coverage to the employee for failure to participate in the wellness program. Part III summarizes how the ADA's reasonable requirement places an obligation on employers to make reasonable accommodation to individuals with disabilities, which will improve the health of working individuals with disabilities. Part IV concludes with suggestions for further reform.

4.
J Biol Chem ; 283(6): 3365-3375, 2008 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-18055454

RESUMO

Sphingosine 1-phosphate (S1P), a sphingolipid metabolite that plays an important role in the regulation of cell survival, growth, migration, and angiogenesis, acts both inside the cells and as an extracellular mediator through binding to five G protein-coupled receptors (S1P(1-5)). Sphingosine kinase 1 (SK1), the enzyme responsible for S1P production, is overexpressed in many solid tumors, including gliomas. One common feature of these tumors is the presence of "hypoxic regions," characterized by cells expressing high levels of hypoxia-inducible factors HIF-1alpha and HIF-2alpha, two transcription regulators that modulate the levels of proteins with crucial roles in tumor progression. So far, nothing is known about the role and the regulation of SK1 during tumor-induced hypoxia or about SK1 regulation and HIFs. Here we investigated the role of HIF-1alpha and HIF-2alpha in the regulation of SK1 during hypoxic stress in glioma-derived U87MG cells. We report that hypoxia increases SK1 mRNA levels, protein expression, and enzyme activity, followed by intracellular S1P production and S1P release. Interestingly, knockdown of HIF-2alpha by small interfering RNA abolished the induction of SK1 and the production of extracellular S1P after CoCl(2) treatment, whereas HIF-1alpha small interfering RNA resulted in an increase of HIF-2alpha and of SK1 protein levels. Moreover, using chromatin immunoprecipitation analysis, we demonstrate that HIF-2alpha binds the SK1 promoter. Functionally, we demonstrate that conditioned medium from hypoxia-treated tumor cells results in neoangiogenesis in human umbilical vein endothelial cells in a S1P receptor-dependent manner. These studies provide evidence of a link between S1P production as a potent angiogenic agent and the hypoxic phenotype observed in many tumors.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Neoplasias Encefálicas/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Fator 1 Induzível por Hipóxia/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Regiões Promotoras Genéticas , Progressão da Doença , Humanos , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Transcrição Gênica , Regulação para Cima
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