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1.
Prev Chronic Dis ; 8(3): A69, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21477509

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States. CRC screening allows for prevention through the removal of precancerous lesions and early detection of cancer. COMMUNITY CONTEXT: Ride for Life Alaska (RFL), a nonprofit organization that raises funds to fight cancer, and the Anchorage Neighborhood Health Center (ANHC), which is Alaska's largest community health center, joined efforts to provide CRC screening and outreach to an ethnically diverse group of low-income underinsured or uninsured patients residing in and around Anchorage, Alaska. METHODS: RFL and ANHC worked with gastroenterologists, medical practices, and pathology services to contribute pro bono and reduced-fee services for CRC screening. Information to patients was distributed through signs in the clinic, flyers, and the ANHC website. OUTCOMES: CRC screening was increased in this population. During 2007-2009, there were 2,561 immunochemical fecal occult blood tests given to patients, and 1,558 were completed (61%); 24% were positive. Sixteen gastroenterologists, 4 medical practices, and 2 laboratories provided 111 follow-up colonoscopies and pathology services to patients identified through the CRC screening program who did not have other funding resources available for follow-up care. INTERPRETATION: This program provides a model for leveraging scarce screening resources by drawing on multiple partners to increase CRC screening. Recommendations for those seeking to initiate similar programs are to have memoranda of agreement in place and a clear scope of work for all participating people and organizations to avoid delays in program implementation; hire a screening care coordinator to manage patient care and collaborate with medical practices; and identify program champions who have the energy and persistence to craft such partnerships.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Centros Comunitarios de Salud , Detección Precoz del Cáncer , Pacientes no Asegurados/estadística & datos numéricos , Pobreza/estadística & datos numéricos , Anciano , Alaska/epidemiología , Neoplasias Colorrectales/prevención & control , Conducta Cooperativa , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Obtención de Fondos , Personal de Salud , Investigación sobre Servicios de Salud , Humanos , Masculino , Persona de Mediana Edad , Organizaciones sin Fines de Lucro
2.
FASEB J ; 22(6): 1649-59, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18180334

RESUMEN

Local physical interactions between cells and extracellular matrix (ECM) influence directional cell motility that is critical for tissue development, wound repair, and cancer metastasis. Here we test the possibility that the precise spatial positioning of focal adhesions governs the direction in which cells spread and move. NIH 3T3 cells were cultured on circular or linear ECM islands, which were created using a microcontact printing technique and were 1 microm wide and of various lengths (1 to 8 microm) and separated by 1 to 4.5 microm wide nonadhesive barrier regions. Cells could be driven proactively to spread and move in particular directions by altering either the interisland spacing or the shape of similar-sized ECM islands. Immunofluorescence microscopy confirmed that focal adhesions assembled preferentially above the ECM islands, with the greatest staining intensity being observed at adhesion sites along the cell periphery. Rac-FRET analysis of living cells revealed that Rac became activated within 2 min after peripheral membrane extensions adhered to new ECM islands, and this activation wave propagated outward in an oriented manner as the cells spread from island to island. A computational model, which incorporates that cells preferentially protrude membrane processes from regions near newly formed focal adhesion contacts, could predict with high accuracy the effects of six different arrangements of micropatterned ECM islands on directional cell spreading. Taken together, these results suggest that physical properties of the ECM may influence directional cell movement by dictating where cells will form new focal adhesions and activate Rac and, hence, govern where new membrane protrusions will form.


Asunto(s)
Movimiento Celular , Adhesiones Focales , Proteínas de Unión al GTP rac/metabolismo , Animales , Adhesión Celular , Extensiones de la Superficie Celular/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestructura , Transferencia Resonante de Energía de Fluorescencia , Ratones , Células 3T3 NIH
3.
J Med Chem ; 61(19): 8797-8810, 2018 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-30204441

RESUMEN

While the treatment of gastrointestinal stromal tumors (GISTs) has been revolutionized by the application of targeted tyrosine kinase inhibitors capable of inhibiting KIT-driven proliferation, diverse mutations to this kinase drive resistance to established therapies. Here we describe the identification of potent pan-KIT mutant kinase inhibitors that can be dosed without being limited by the tolerability issues seen with multitargeted agents. This effort focused on identification and optimization of an existing kinase scaffold through the use of structure-based design. Starting from a series of previously reported phenoxyquinazoline and quinoline based inhibitors of the tyrosine kinase PDGFRα, potency against a diverse panel of mutant KIT driven Ba/F3 cell lines was optimized, with a particular focus on reducing activity against a KDR driven cell model in order to limit the potential for hypertension commonly seen in second and third line GIST therapies. AZD3229 demonstrates potent single digit nM growth inhibition across a broad cell panel, with good margin to KDR-driven effects. Selectivity over KDR can be rationalized predominantly by the interaction of water molecules with the protein and ligand in the active site, and its kinome selectivity is similar to the best of the approved GIST agents. This compound demonstrates excellent cross-species pharmacokinetics, shows strong pharmacodynamic inhibition of target, and is active in several in vivo models of GIST.


Asunto(s)
Descubrimiento de Drogas , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Proteínas Mutantes/antagonistas & inhibidores , Mutación , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-kit/antagonistas & inhibidores , Quinazolinas/química , Quinazolinas/farmacología , Triazoles/química , Triazoles/farmacología , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/metabolismo , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/metabolismo , Tumores del Estroma Gastrointestinal/patología , Humanos , Modelos Moleculares , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Conformación Proteica , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Quinazolinas/farmacocinética , Distribución Tisular , Triazoles/farmacocinética , Células Tumorales Cultivadas
4.
Sci Adv ; 4(6): eaat1719, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29938225

RESUMEN

Poor survival rates of patients with tumors arising from or disseminating into the brain are attributed to an inability to excise all tumor tissue (if operable), a lack of blood-brain barrier (BBB) penetration of chemotherapies/targeted agents, and an intrinsic tumor radio-/chemo-resistance. Ataxia-telangiectasia mutated (ATM) protein orchestrates the cellular DNA damage response (DDR) to cytotoxic DNA double-strand breaks induced by ionizing radiation (IR). ATM genetic ablation or pharmacological inhibition results in tumor cell hypersensitivity to IR. We report the primary pharmacology of the clinical-grade, exquisitely potent (cell IC50, 0.78 nM), highly selective [>10,000-fold over kinases within the same phosphatidylinositol 3-kinase-related kinase (PIKK) family], orally bioavailable ATM inhibitor AZD1390 specifically optimized for BBB penetration confirmed in cynomolgus monkey brain positron emission tomography (PET) imaging of microdosed 11C-labeled AZD1390 (Kp,uu, 0.33). AZD1390 blocks ATM-dependent DDR pathway activity and combines with radiation to induce G2 cell cycle phase accumulation, micronuclei, and apoptosis. AZD1390 radiosensitizes glioma and lung cancer cell lines, with p53 mutant glioma cells generally being more radiosensitized than wild type. In in vivo syngeneic and patient-derived glioma as well as orthotopic lung-brain metastatic models, AZD1390 dosed in combination with daily fractions of IR (whole-brain or stereotactic radiotherapy) significantly induced tumor regressions and increased animal survival compared to IR treatment alone. We established a pharmacokinetic-pharmacodynamic-efficacy relationship by correlating free brain concentrations, tumor phospho-ATM/phospho-Rad50 inhibition, apoptotic biomarker (cleaved caspase-3) induction, tumor regression, and survival. On the basis of the data presented here, AZD1390 is now in early clinical development for use as a radiosensitizer in central nervous system malignancies.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Inhibidores de Proteínas Quinasas/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Apoptosis/efectos de los fármacos , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Humanos , Ratones , Fosforilación , Inhibidores de Proteínas Quinasas/química , Tolerancia a Radiación/efectos de los fármacos , Fármacos Sensibilizantes a Radiaciones/química , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Rayos X , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Biomed Microdevices ; 8(4): 299-308, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17003962

RESUMEN

This paper describes a miniaturized, integrated, microfluidic device that can pull molecules and living cells bound to magnetic particles from one laminar flow path to another by applying a local magnetic field gradient, and thus selectively remove them from flowing biological fluids without any wash steps. To accomplish this, a microfabricated high-gradient magnetic field concentrator (HGMC) was integrated at one side of a microfluidic channel with two inlets and outlets. When magnetic micro- or nano-particles were introduced into one flow path, they remained limited to that flow stream. In contrast, when the HGMC was magnetized, the magnetic beads were efficiently pulled from the initial flow path into the collection stream, thereby cleansing the original fluid. Using this microdevice, living E. coli bacteria bound to magnetic nanoparticles were efficiently removed from flowing solutions containing densities of red blood cells similar to that found in blood. Because this microdevice allows large numbers of beads and cells to be sorted simultaneously, has no capacity limit, and does not lose separation efficiency as particles are removed, it may be especially useful for separations from blood or other clinical samples. This on-chip HGMC-microfluidic separator technology may potentially allow cell separations to be carried out in the field outside of hospitals and clinical laboratories.


Asunto(s)
Escherichia coli/citología , Microfluídica , Nanopartículas , Separación Celular/instrumentación , Separación Celular/métodos , Magnetismo , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/instrumentación , Microfluídica/métodos
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