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1.
Cell Commun Signal ; 20(1): 4, 2022 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-34998412

RESUMO

BACKGROUND: Research is revealing the complex coordination between cell signaling systems as they adapt to genetic and epigenetic changes. Tools to uncover these highly complex functional linkages will play an important role in advancing more efficacious disease treatments. Current tumor cell signal transduction research is identifying coordination between receptor types, receptor families, and transduction pathways to maintain tumor cell viability despite challenging tumor microenvironment conditions. METHODS: In this report, coactivated abnormal levels of signaling activity for c-Met and HER family receptors in live tumor cells were measured by a new clinical test to identify a subpopulation of breast cancer patients that could be responsive to combined targeted therapies. The CELsignia Multi-Pathway Signaling Function (CELsignia) Test uses an impedance biosensor to quantify an individual patient's ex vivo live tumor cell signaling response in real-time to specific HER family and c-Met co-stimulation and targeted therapies. RESULTS: The test identified breast tumors with hyperactive HER1, HER2, HER3/4, and c-Met coordinated signaling that express otherwise normal amounts of these receptors. The supporting data of the pre-clinical verification of this test included analyses of 79 breast cancer patients' cell response to HER and c-Met agonists. The signaling results were confirmed using clinically approved matching targeted drugs, and combinations of targeted drugs in addition to correlative mouse xenograft tumor response to HER and c-Met targeted therapies. CONCLUSIONS: The results of this study demonstrated the potential benefit of a functional test for identifying a subpopulation of breast cancer patients with coordinated abnormal HER and c-Met signaling for a clinical trial testing combination targeted therapy. Video Abstract.


Assuntos
Neoplasias da Mama , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Receptor ErbB-2/metabolismo , Transdução de Sinais , Microambiente Tumoral
2.
BMC Cancer ; 17(1): 199, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28302091

RESUMO

BACKGROUND: Approximately 18-20% of all human breast cancers have overexpressed human epidermal growth factor receptor 2 (HER2). Standard clinical practice is to treat only overexpressed HER2 (HER2+) cancers with targeted anti-HER2 therapies. However, recent analyses of clinical trial data have found evidence that HER2-targeted therapies may benefit a sub-group of breast cancer patients with non-overexpressed HER2. This suggests that measurement of other biological factors associated with HER2 cancer, such as HER2 signaling pathway activity, should be considered as an alternative means of identifying patients eligible for HER2 therapies. METHODS: A new biosensor-based test (CELxTM HSF) that measures HER2 signaling activity in live cells is demonstrated using a set of 19 human HER2+ and HER2- breast cancer reference cell lines and primary cell samples derived from two fresh patient tumor specimens. Pathway signaling is elucidated by use of highly specific agonists and antagonists. The test method relies upon well-established phenotypic, adhesion-related, impedance changes detected by the biosensor. RESULTS: The analytical sensitivity and analyte specificity of this method was demonstrated using ligands with high affinity and specificity for HER1 and HER3. The HER2-driven signaling quantified ranged 50-fold between the lowest and highest cell lines. The HER2+ cell lines were almost equally divided into high and low signaling test result groups, suggesting that little correlation exists between HER2 protein expression and HER2 signaling level. Unexpectedly, the highest HER2-driven signaling level recorded was with a HER2- cell line. CONCLUSIONS: Measurement of HER2 signaling activity in the tumor cells of breast cancer patients is a feasible approach to explore as a biomarker to identify HER2-driven cancers not currently diagnosable with genomic techniques. The wide range of HER2-driven signaling levels measured suggests it may be possible to make a distinction between normal and abnormal levels of activity. Analytical validation studies and clinical trials treating HER2- patients with abnormal HER2-driven signaling would be required to evaluate the analytical and clinical validity of using this functional biomarker as a diagnostic test to select patients for treatment with HER2 targeted therapy. In clinical practice, this method would require patient specimens be delivered to and tested in a central lab.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptor ErbB-2/isolamento & purificação , Técnicas Biossensoriais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Prognóstico , Receptor ErbB-2/genética
3.
Angew Chem Int Ed Engl ; 56(6): 1557-1560, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28044396

RESUMO

Methods for positionally selective remote C-H functionalizations are in high demand. Herein, we disclose the first heterogeneous ruthenium catalyst for meta-selective C-H functionalizations, which enabled remote halogenations with excellent site selectivity and ample scope. The versatile heterogeneous Ru@SiO2 catalyst was broadly applicable and could be easily recovered and reused, which set the stage for the direct fluorescent labeling of purines. In contrast to palladium, rhodium, iridium, or cobalt complexes, solely the ruthenium catalysis manifold provided access to meta-halogenated purine derivatives, illustrating the unique power of ruthenium C-H activation catalysis.

4.
J Am Chem Soc ; 138(37): 12252-7, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27545044

RESUMO

The Rh(III)-catalyzed oxidative C-H allylation of N-acetylbenzamides with 1,3-dienes is described. The presence of allylic hydrogens cis to the less substituted alkene of the 1,3-diene is important for the success of these reactions. With the assistance of reactions using deuterated 1,3-dienes, a proposed mechanism is provided. The key step is postulated to be the first reported examples of allyl-to-allyl 1,4-Rh(III) migration.

5.
Angew Chem Int Ed Engl ; 54(25): 7410-3, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25959544

RESUMO

A commercially available rhodium(II) complex catalyzes the direct arylation of 5-diazobarbituric acids with arenes, allowing straightforward access to 5-aryl barbituric acids. Free N-H groups are tolerated on the barbituric acid, with no complications arising from N-H insertion processes. This method was applied to the concise synthesis of a potent matrix metalloproteinase (MMP) inhibitor.


Assuntos
Compostos Azo/química , Barbitúricos/síntese química , Hidrocarbonetos Aromáticos/síntese química , Ródio/química , Compostos Azo/síntese química , Barbitúricos/química , Catálise , Hidrocarbonetos Aromáticos/química , Inibidores de Metaloproteinases de Matriz/síntese química , Inibidores de Metaloproteinases de Matriz/química
6.
Angew Chem Int Ed Engl ; 54(47): 13975-9, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26404643

RESUMO

Chiral cyclopentadienyl rhodium complexes promote highly enantioselective enol-directed C(sp(2))-H functionalization and oxidative annulation with alkynes to give spiroindenes containing all-carbon quaternary stereocenters. High selectivity between two possible directing groups, as well as control of the direction of rotation in the isomerization of an O-bound rhodium enolate into the C-bound isomer, appear to be critical for high enantiomeric excesses.

7.
Angew Chem Int Ed Engl ; 54(34): 9958-62, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26224377

RESUMO

1,3-Enynes containing allylic hydrogens cis to the alkyne function as three-carbon components in rhodium(III)-catalyzed, all-carbon [3+3] oxidative annulations to produce spirodialins. The proposed mechanism of these reactions involves the alkenyl-to-allyl 1,4-rhodium(III) migration.

8.
Chemistry ; 20(28): 8599-602, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24909937

RESUMO

The dearomatizing oxidative annulation of 2-alkenylphenols with alkynes and enynes proceeds with high yields and regioselectivities under Rh(III) catalysis. These reactions are successful using Cu(OAc)2 or air as the stoichiometric oxidant, and provide spirocyclic enones, the basic ring system of which appears in several natural products. Application of this process to the preparation of a highly functionalized tetracycle is also demonstrated.


Assuntos
Alcinos/química , Alcinos/síntese química , Ródio/química , Catálise , Ciclização , Estrutura Molecular , Oxirredução
9.
Angew Chem Int Ed Engl ; 53(37): 9931-5, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25048465

RESUMO

1,3-Enynes containing allylic hydrogens cis to the alkyne are shown to act as one-carbon partners, rather than two-carbon partners, in various rhodium-catalyzed oxidative annulations. The mechanism of these unexpected transformations is proposed to occur through double C-H activation, involving a hitherto rare example of the 1,4-migration of a Rh(III) species. This phenomenon is general across a variety of substrates, and provides a diverse range of heterocyclic products.

10.
Hosp Top ; 91(4): 69-80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24255935

RESUMO

The expectation that aging leads to a progressive deterioration of biological functions leading to higher healthcare costs is known as the healthcare cost creep due to age creep phenomenon. The authors empirically test the validity of this phenomenon in the context of hospitalization costs based on more than 8 million hospital inpatient records from 1,056 hospitals in the United States. The results question the existence of cost creep due to age creep after the age of 65 years as far as average hospitalization costs are concerned. The authors discuss implications for potential knowledge transfer for cost minimization and medical tourism.


Assuntos
Custos Hospitalares/tendências , Admissão do Paciente/economia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Bases de Dados Factuais , Humanos , Lactente , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estados Unidos , Adulto Jovem
11.
Org Biomol Chem ; 10(38): 7666-8, 2012 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22930235

RESUMO

Due to the lack of availability of unnatural (+)-quinic acid as a starting material, a 6-step synthesis of butane diacetal-protected (4S,5S)-dihydroxycyclohexen-1-one (formally derived from (+)-quinic acid) has been devised. The key catalytic asymmetric step involves a chiral Co-salen-catalysed epoxide ring-opening reaction. (4S,5S)-Dihydroxycyclohexen-1-one was utilised in the synthesis of two cyclohexenone natural products isolated from the mycelia of Lasiodiplodia theobromae.


Assuntos
Acetais/química , Produtos Biológicos/síntese química , Cobalto/química , Cicloexanonas/síntese química , Etilenodiaminas/química , Compostos Organometálicos/química , Ascomicetos/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Catálise , Cicloexanonas/química , Cicloexanonas/isolamento & purificação , Estrutura Molecular
12.
Org Lett ; 24(2): 686-691, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34995469

RESUMO

A mild and inexpensive method for direct hydrodecarboxylation of aliphatic carboxylic acids has been developed. The reaction does not require metals, light, or catalysts, rendering the protocol operationally simple, easy to scale, and more sustainable. Crucially, no additional H atom source is required in most cases, while a broad substrate scope and functional group tolerance are observed.

13.
Org Lett ; 22(17): 6977-6981, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32845648

RESUMO

Gold-catalyzed hydroarylation of unactivated alkynes with indoles have previously been reported to proceed with double indole addition to produce symmetrical bis(indolyl)methanes (BIMs). We demonstrate for the first time that the selectivity of the gold-catalyzed reaction can be fully switched to allow for isolation of the vinylindole products instead. Furthermore, this selective reaction can be utilized to synthesize the more difficult to access unsymmetrical BIMs from readily available starting materials.

14.
J Cancer Res Clin Oncol ; 146(3): 605-619, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32036454

RESUMO

PURPOSE: HER2 signaling functional activity may be important to measure in addition to HER2 protein quantification when identifying patients eligible for HER2 therapies. A HER2 Signaling Function (CELx HSF) Test for HER2-negative patients uses patient's live tumor cells on a biosensor to identify patients with abnormally high HER2-related signaling (HSFs+) likely to respond to anti-HER2 therapies. METHODS: The CELx HSF test was employed to: (1) characterize the sensitivity and specificity of the test to detect abnormal levels of HER2 signaling; (2) evaluate the inhibitory effectiveness of five different anti-HER2 therapies; (3) assess the correlation between CELx HSF test detection of abnormal HER2 signaling and response to HER2 therapy using xenograft models; and (4) confirm the prevalence of abnormal HER2 signaling amongst HER2-negative breast cancer patients (HER2-/HSFs+). RESULTS: HER2-/HSFs+ breast cancer patient samples were identified and showed sensitivity to five approved anti-HER2 therapies. Xenograft studies using both HER2+ and HER2- cell lines confirmed that CELx HER2 signaling status better predicts HER2 inhibitor efficacy than HER2 receptor status. In a study of 114 HER2-negative breast tumor patient samples, 27 (23.7%; 95% CI = 17-32%) had abnormal HER2 signaling (HSFs+). A ROC curve constructed with this dataset projects the CELx HSF Test would have greater than 90% sensitivity and specificity to detect the HER2-/HSFs+ patient population. CONCLUSIONS: The CELx HSF test is a well-characterized functional biomarker assay capable of identifying dynamic HER2-driven signaling dysfunction in tumor cells from HER2-negative breast cancer patients. This test has demonstrated efficacy of various HER2 targeted therapies in live tumor cells from the HSFs+ population and correlated the test result to HER2 drug response in mouse xenograft studies. The proportion of HER2-negative breast cancer patients found to have abnormal HER2 signaling in a 114 patient sample study, 20-25%, is significant. A clinical trial to evaluate the efficacy of anti-HER2 therapies in this patient population is warranted.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais/fisiologia , Animais , Antineoplásicos/farmacologia , Impedância Elétrica , Feminino , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Artigo em Inglês | MEDLINE | ID: mdl-19119084

RESUMO

Abnormal elevation of 11beta-HSD1 activities in tissues, such as fat and brain, may contribute to the development of the abdominal obesity and Alzheimer disease, and the inhibition of 11beta-HSD1 might be beneficial to the management of these diseases. To assess the effects of pharmacologic inhibitors of 11beta-HSD1, we developed a fast LC/MS/MS method to quantify corticosteroids in minced tissue samples in the presence of 11beta-HSD substrates. The novel on-line SPE-LC/MS/MS method was developed with dual binary gradient and a throughput of 4.5 min/sample. A total of six corticosteroids (cortisol, cortisone, corticosterone, dehydrocorticosterone, dexamethasone, and dehydrodexamethasone) were studied. The lower limit of quantitation from 0.40 to 11.4 fmol and 4.5 orders magnitude of dynamic range were obtained for these six compounds. Three novel enzymatic bi-products, all isomers of cortisol, were observed in the liver or fat samples. Two of them were identified by matching the HPLC retention times and MS/MS spectra with authentic compounds. The potential interferences of these isomers and their removal are discussed.


Assuntos
11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Corticosteroides/análise , Cromatografia Líquida , Extração em Fase Sólida , Espectrometria de Massas em Tandem , 11-beta-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Corticosteroides/metabolismo , Animais , Química Encefálica , Epididimo/química , Desenho de Equipamento , Rim/química , Modelos Lineares , Fígado/química , Masculino , Camundongos , Sensibilidade e Especificidade
16.
Chem Commun (Camb) ; 55(29): 4238-4241, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30900714

RESUMO

The use of copper catalysis with visible light photoredox catalysis in a cooperative fashion has recently emerged as a versatile means of developing new C-C bond forming reactions. In this work, dual copper and photoredox catalysis is exploited to effect C(sp2)-C(sp3) cross-couplings between aryl boronic acids and benzyl bromides.

17.
J Neurosci Res ; 86(10): 2214-26, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18438921

RESUMO

Activation of the Rho kinase (ROCK) pathway has been associated with inhibition of neurite regeneration and outgrowth in spinal cord injury. Growth-inhibitory substances present in the glial scar such as chondroitin sulfate proteoglycans (CSPGs) have been shown to create a nonpermissive environment for axon regeneration that results in growth cone collapse. In this study, an in vitro model was developed in nerve growth factor-differentiated PC12 cells where the Rho/ROCK pathway was modulated by CSPG. CSPG elicited concentration-dependent inhibition of neurite outgrowth in PC12 cells, which was reversed by ROCK inhibitors such as fasudil, dimethylfasudil, and Y27632. Further studies on the interactions of CSPG with ROCK inhibitors revealed that the modulation of ROCK by CSPG is noncompetitive in nature. It was also observed that ROCK inhibitors increased neurite outgrowth in undifferentiated PC12 cells, indicating constitutive ROCK activity in the cells. Analysis of signaling pathways demonstrated that the effect of CSPG increases the phosphorylation of myosin phosphatase, a substrate immediately downstream of ROCK activation. Fasudil, dimethylfasudil, and Y27632 inhibited the phosphorylation of myosin phosphatase induced by CSPG with rank order potencies comparable to those observed in the neurite outgrowth assay. In addition, ROCK inhibitors reversed cofilin phosphorylation induced by CSPG with similar rank order potencies. Taken together, our data demonstrate that the interaction of CSPG with the ROCK pathway involves downstream effectors of ROCK such as myosin phosphatase and cofilin.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/metabolismo , Neuritos/metabolismo , Transdução de Sinais/fisiologia , Quinases Associadas a rho/metabolismo , Animais , Cofilina 1/metabolismo , Inibidores Enzimáticos/farmacologia , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Neuritos/efeitos dos fármacos , Células PC12 , Fosforilação , Ratos , Transdução de Sinais/efeitos dos fármacos
18.
J Biomol Screen ; 13(6): 527-37, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18566484

RESUMO

Prioritization of compounds based on human hepatotoxicity potential is currently a key unmet need in drug discovery, as it can become a major problem for several lead compounds in later stages of the drug discovery pipeline. The authors report the validation and implementation of a high-content multiparametric cytotoxicity assay based on simultaneous measurement of 8 key cell health indicators associated with nuclear morphology, plasma membrane integrity, mitochondrial function, and cell proliferation. Compounds are prioritized by (a) computing an in vitro safety margin using the minimum cytotoxic concentration (IC(20)) across all 8 indicators and cell-based efficacy data and (b) using the minimal cytotoxic concentration alone to take into account concentration of drug in tissues. Feasibility data using selected compounds, including quinolone antibiotics, thiazolidinediones, and statins, suggest the viability of this approach. To increase overall throughput of compound prioritization, the authors have identified the higher throughput, plate reader-based CyQUANT assay that is similar to the high-content screening (HCS) assay in sensitivity of measuring inhibition of cell proliferation. It is expected that the phenotypic output from the multiparametric HCS assay in combination with other highly sensitive approaches, such as microarray-based expression analysis of toxic signatures, will contribute to a better understanding and predictivity of human hepatotoxicity potential.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hepatócitos/efeitos dos fármacos , Testes de Toxicidade/métodos , Xenobióticos/toxicidade , Bioensaio , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Xenobióticos/classificação
19.
Health Mark Q ; 25(3): 254-69, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19042547

RESUMO

Hospitals are a significant part of the burgeoning healthcare sector in the United States (U.S.) economy. Despite the availability of what some describe as the world's best healthcare, the U.S. suffers from wide discrepancies in healthcare provision across hospitals and regions of the country. Specifically, capacity, utilization, quality, and even financial performance of hospitals vary widely. Based on secondary data from 533 hospitals in the adjoining states of Indiana, Kentucky, and Ohio, this study develops several comparative metrics that enable benchmarking, which, in turn, leads to several inferences and implications for hospital administrators. The paper concludes with implications for hospital administrators and suggestions for future research.


Assuntos
Hospitais/provisão & distribuição , Demografia , Economia Hospitalar/estatística & dados numéricos , Número de Leitos em Hospital/economia , Número de Leitos em Hospital/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Hospitais/normas , Hospitais/estatística & dados numéricos , Hospitais com Fins Lucrativos/economia , Hospitais com Fins Lucrativos/estatística & dados numéricos , Humanos , Indiana , Kentucky , Marketing de Serviços de Saúde/economia , Ohio , Ambulatório Hospitalar/estatística & dados numéricos , Ambulatório Hospitalar/provisão & distribuição , Qualidade da Assistência à Saúde
20.
J Biomol Screen ; 12(7): 938-45, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17942786

RESUMO

A 384-well soft agar assay was developed to identify potential novel anticancer compounds. Normally used to detect cell transformation, the assay is used here to quantitate cell proliferation in a 3-dimensional (3-D) anchorage-independent format. HCC827 cells, which are highly sensitive to epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors, were used to develop the method and a set of 9600 compounds used to validate the assay. Results were compared to a monolayer assay using the same compound set. The assay provides a robust method to discover compounds that could be missed using traditional monolayer formats.


Assuntos
Antineoplásicos/química , Inibidores Enzimáticos/química , Ágar , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Humanos
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