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1.
Mol Cancer ; 22(1): 206, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093346

RESUMO

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Altruísmo , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , Neoplasias da Mama/genética
2.
Am J Otolaryngol ; 44(2): 103765, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36603380

RESUMO

OBJECTIVES: To assess the use of tongue base palpation during cancer screening exams by Oral Healthcare Providers (OHPs) and explore attitudes about (1) the usefulness of oral cancer screening (OCS) in detecting early, asymptomatic lesions and (2) routine OCS of the general population. STUDY DESIGN: Survey study. SETTING: Private and hospital-based clinical practices of OHPs located in Massachusetts and Connecticut, United States. METHODS: An anonymous, online 9-item survey assessing beliefs and practice patterns about cancer screening exams was distributed to OHPs with practices in Massachusetts and Connecticut from August 2020 to June 2021. Data were analyzed using chi-square tests and Pearson correlations. Statistically significant levels were established at P < .050. RESULTS: One hundred seventy-one responses were analyzed (response rate 17 %). Tongue base palpation was performed as part of a routine cancer screening exam by 55 % of otolaryngologists, 34 % of dentists and 29 % of OMFS (P = .030). Providers who palpated the tongue base were also more likely to use palpation as an exam technique in the tonsils (r = 0.52 [95 % CI 0.40-0.62]; P < .001) among other intra-and extra-oral anatomical subsites. Almost all dentists (92 %) and OMFS (98 %) but only 58 % of otolaryngologists considered OCS useful for detection of early, asymptomatic malignant lesions in the oral cavity (P < .001). CONCLUSIONS: While tongue base palpation can detect oropharyngeal cancers in a pre-symptomatic stage, it is underutilized during routine cancer screening exams. Considering the rising incidence of oropharyngeal cancer, tongue base palpation should be established as a routine part of cancer screening by OHPs.


Assuntos
Neoplasias Bucais , Neoplasias Orofaríngeas , Neoplasias da Língua , Humanos , Estados Unidos , Estudos Transversais , Neoplasias Bucais/diagnóstico , Neoplasias Orofaríngeas/diagnóstico , Pessoal de Saúde , Inquéritos e Questionários , Língua , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/epidemiologia
4.
Br J Pharmacol ; 179(12): 2829-2843, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33533478

RESUMO

The Popeye domain-containing protein 1 (POPDC1), a tight junction-associated transmembrane protein with a unique binding site for cAMP, has been shown to act as a tumour suppressor in cancer cells. Through interaction with many downstream effectors and signalling pathways, POPDC1 promotes cell adhesion and inhibits uncontrolled cell proliferation, epithelial-to-mesenchymal transition and metastasis. However, POPDC1 expression is down-regulated in many types of cancer, thereby reducing its tumour-suppressive actions. This review discusses the role of POPDC1 in the progression of the malignant phenotype and highlights the broad range of benefits POPDC1 stabilisation may achieve therapeutically. Cancer stem cells (CSCs) are a key hallmark of malignancies and commonly promote treatment resistance. This article provides a comprehensive overview of CSC signalling mechanisms, many of which have been shown to be regulated by POPDC1 in other cell types, thus suggesting an additional therapeutic benefit for POPDC1-stabilising anti-cancer drugs. LINKED ARTICLES: This article is part of a themed issue on New avenues in cancer prevention and treatment (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.12/issuetoc.


Assuntos
Moléculas de Adesão Celular , Transdução de Sinais , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Proliferação de Células , Fenótipo
5.
BMC Med ; 19(1): 199, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34404389

RESUMO

BACKGROUND: The use of proactive genetic screening for disease prevention and early detection is not yet widespread. Professional practice guidelines from the American College of Medical Genetics and Genomics (ACMG) have encouraged reporting pathogenic variants that confer personal risk for actionable monogenic hereditary disorders, but only as secondary findings from exome or genome sequencing. The Centers for Disease Control and Prevention (CDC) recognizes the potential public health impact of three Tier 1 actionable disorders. Here, we report results of a large multi-center cohort study to determine the yield and potential value of screening healthy individuals for variants associated with a broad range of actionable monogenic disorders, outside the context of secondary findings. METHODS: Eligible adults were offered a proactive genetic screening test by health care providers in a variety of clinical settings. The screening panel based on next-generation sequencing contained up to 147 genes associated with monogenic disorders within cancer, cardiovascular, and other important clinical areas. Sequence and intragenic copy number variants classified as pathogenic, likely pathogenic, pathogenic (low penetrance), or increased risk allele were considered clinically significant and reported. Results were analyzed by clinical area and severity/burden of disease using chi-square tests without Yates' correction. RESULTS: Among 10,478 unrelated adults screened, 1619 (15.5%) had results indicating personal risk for an actionable monogenic disorder. In contrast, only 3.1 to 5.2% had clinically reportable variants in genes suggested by the ACMG version 2 secondary findings list to be examined during exome or genome sequencing, and 2% had reportable variants related to CDC Tier 1 conditions. Among patients, 649 (6.2%) were positive for a genotype associated with a disease of high severity/burden, including hereditary cancer syndromes, cardiovascular disorders, or malignant hyperthermia susceptibility. CONCLUSIONS: This is one of the first real-world examples of specialists and primary care providers using genetic screening with a multi-gene panel to identify health risks in their patients. Nearly one in six individuals screened for variants associated with actionable monogenic disorders had clinically significant results. These findings provide a foundation for further studies to assess the role of genetic screening as part of regular medical care.


Assuntos
Testes Genéticos , Médicos , Adulto , Estudos de Coortes , Exoma , Predisposição Genética para Doença , Genômica , Humanos
6.
Biosci Rep ; 37(6)2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-28954821

RESUMO

Breast cancer subtypes such as triple-negative that lack the expression of oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor 2 receptor (HER2), remain poorly clinically managed due to a lack of therapeutic targets. This necessitates identification and validation of novel targets. Suppression of Popeye domain-containing protein 1 (POPDC1) is known to promote tumorigenesis and correlate to poor clinical outcomes in various cancers, and also promotes cardiac and skeletal muscle pathologies. It remains to be established whether POPDC1 is dysregulated in breast cancer, and whether overcoming the dysregulation of POPDC1 could present a potential therapeutic strategy to inhibit breast tumorigenesis. We assessed the potential of POPDC1 as a novel target for inhibiting breast cancer cell migration and proliferation. POPDC1 was significantly suppressed with reduced cell membrane localization in breast cancer cells. Furthermore, functional suppression of POPDC1 promoted breast cancer cell migration and proliferation, which were inhibited by POPDC1 overexpression. Finally, cAMP interacts with POPDC1 and up-regulates its expression in breast cancer cells. These findings suggest that POPDC1 plays a role in breast tumorigenesis and represents a potential therapeutic target or biomarker in breast cancer medicine.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Carcinogênese/metabolismo , Proteínas de Membrana/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Carcinogênese/genética , Moléculas de Adesão Celular , Movimento Celular , Proliferação de Células , AMP Cíclico/metabolismo , Feminino , Humanos , Células MCF-7 , Proteínas de Membrana/genética , Proteínas Musculares , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
8.
Cancer Lett ; 406: 81-92, 2017 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-28807821

RESUMO

Breast cancer molecular heterogeneity has resulted in disparities in therapeutic response and targeting of molecular subtypes of breast cancer. This necessitates identification and validation of novel therapeutic targets for breast cancer treatment. Suppression of Popeye domain-containing (POPDC) proteins is hypothesized to promote malignant cell behaviour and poor clinical outcomes in various cancers. We aimed to determine whether POPDC proteins are suppressed in human ductal carcinoma tissues and if this correlates to clinical progression and Her2 status. We further assessed if the EGFR regulated POPDC1 in breast cancer. Here we show significant suppression of POPDC1 in malignant breast cancer tissues without correlation to clinical progression. Interestingly, POPDC2 and POPDC3 were highly expressed in malignant breast tissues. Furthermore, HER2+ status significantly correlated with high POPDC2 and POPDC3, but not POPDC1 expression. We further show for the first time that low POPDC1 correlates to high EGFR expression in breast cancer tissues and that EGFR negatively regulates POPDC1 expression in MCF7, MDA231 and SKBR3 breast cancer cells. Furthermore, overexpression of POPDC1 in MCF7, MDA231 and SKBR3 cells attenuated EGF-mediated cell migration and proliferation. These findings show that POPDC1 is suppressed in breast cancer and can potentially be targeted to inhibit EGFR-mediated cell migration and proliferation.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Receptores ErbB/metabolismo , Proteínas de Membrana/metabolismo , Apoptose , Western Blotting , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Proteínas Musculares/metabolismo , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/metabolismo , Células Tumorais Cultivadas
9.
Clin Chem ; 63(3): 731-741, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28073899

RESUMO

BACKGROUND: Molecular characterization of circulating tumor cells (CTCs) holds great promise for monitoring metastatic progression and characterizing metastatic disease. However, leukocyte and red blood cell contamination of routinely isolated CTCs makes CTC-specific molecular characterization extremely challenging. METHODS: Here we report the use of a paper-based medium for efficient extraction of microRNAs (miRNAs) from limited amounts of biological samples such as rare CTCs harvested from cancer patient blood. Specifically, we devised a workflow involving the use of Flinders Technology Associates (FTA)® Elute Card with a digital PCR-inspired "partitioning" method to extract and purify miRNAs from plasma and CTCs. RESULTS: We demonstrated the sensitivity of this method to detect miRNA expression from as few as 3 cancer cells spiked into human blood. Using this method, background miRNA expression was excluded from contaminating blood cells, and CTC-specific miRNA expression profiles were derived from breast and colorectal cancer patients. Plasma separated out during purification of CTCs could likewise be processed using the same paper-based method for miRNA detection, thereby maximizing the amount of patient-specific information that can be derived from a single blood draw. CONCLUSIONS: Overall, this paper-based extraction method enables an efficient, cost-effective workflow for maximized recovery of small RNAs from limited biological samples for downstream molecular analyses.


Assuntos
Perfilação da Expressão Gênica/métodos , MicroRNAs/sangue , MicroRNAs/genética , Células Neoplásicas Circulantes/metabolismo , Papel , Humanos , MicroRNAs/análise , MicroRNAs/isolamento & purificação , Células Neoplásicas Circulantes/patologia , Células Tumorais Cultivadas
10.
Ocul Oncol Pathol ; 3(4): 250-253, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29344475

RESUMO

PURPOSE: Ciliary body mesectodermal leiomyoma is a rare, benign smooth muscle tumor that typically presents in women in the second to fourth decade of life. The diagnosis is typically based on clinical color, funduscopic appearance, transillumination properties, and B-scan ultrasonography. METHODS: We present a patient with a 360° ciliary body mass with transillumination and ultrasonographic properties consistent with a ring melanoma. RESULTS: This case emphasizes the difficulty in differentiating the benign leiomyoma from similar appearing malignant tumors such as melanoma. CONCLUSION: The eye was enucleated and the diagnosis was ring-shaped leiomyoma.

11.
12.
Drug Discov Today ; 21(12): 1920-1927, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27458118

RESUMO

Popeye domain-containing (POPDC) proteins are a novel class of cAMP-binding molecules that affect cancer cell behaviour and correlate with poor clinical outcomes. They are encoded by the POPDC genes POPDC1, POPDC2, and POPDC3. The deletion of POPDC genes and the suppression of POPDC proteins correlate with enhanced cancer cell proliferation, migration, invasion, metastasis, drug resistance, and poor patient survival in various human cancers. Overexpression of POPDC proteins inhibits cancer cell migration and invasion in vitro. POPDC proteins present promising anticancer therapeutic targets and here we review their roles in promoting cancer progression and highlight their potential as anticancer therapeutic targets.


Assuntos
Moléculas de Adesão Celular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Neoplasias/metabolismo , Animais , Moléculas de Adesão Celular/genética , Humanos , Proteínas de Membrana/genética , Proteínas Musculares/genética , Neoplasias/tratamento farmacológico
13.
J Cataract Refract Surg ; 42(2): 239-45, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27026448

RESUMO

PURPOSE: To determine practice patterns with regard to intraocular lens (IOL) placement during cataract surgery when there is inadequate capsule support for intracapsular or sulcus IOL placement. SETTING: Pennsylvania State College of Medicine, Hershey, Pennsylvania, USA. DESIGN: Cross-sectional study of anonymous survey results. METHODS: An online survey was e-mailed to the coordinators of all Accreditation Council for Graduate Medical Education-accredited ophthalmology residency programs with a request to forward to all faculty who perform cataract surgery. RESULTS: Sixty-seven (57.2%) of 117 confirmed survey recipients participated. Thirty-six (62.1%) said they felt comfortable placing scleral-fixated posterior chamber IOLs (PC IOLs) independently. Faced with inadequate capsule support, 58.6% would place a primary anterior chamber IOL (AC IOL), 29.3% would place a primary scleral-fixated PC IOL, and 5.3% would leave the patient aphakic for secondary scleral-fixated PC IOL placement. Surgeons not comfortable placing scleral-fixated PC IOLs were most likely to choose primary AC IOLs (77.3%). Surgeons comfortable placing scleral-fixated PC IOLs were more evenly divided between primary AC IOLs (47.2%) and scleral-fixated PC IOLs (41.7%). Among surgeons who favored primary scleral-fixated PC IOLs, 63.7% cited a decreased risk for long-term complications as their reason for IOL choice; 50.0% of surgeons who favored primary AC IOLs cited avoidance of a second surgery. CONCLUSIONS: In general, primary AC IOL placement was preferred in the setting of inadequate capsule support, although less so among surgeons who were comfortable placing scleral-fixated PC IOLs. Lack of comfort with scleral-fixated PC IOL placement suggests a potential unmet training need in residency and fellowship programs. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Cápsula do Cristalino/patologia , Implante de Lente Intraocular/métodos , Facoemulsificação , Padrões de Prática Médica/estatística & dados numéricos , Centros Médicos Acadêmicos/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Câmara Anterior/cirurgia , Competência Clínica , Estudos Transversais , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Avaliação Educacional , Feminino , Inquéritos Epidemiológicos , Humanos , Internato e Residência , Lentes Intraoculares , Masculino , Pessoa de Meia-Idade , Oftalmologia/educação , Oftalmologia/estatística & dados numéricos , Facoemulsificação/educação , Facoemulsificação/estatística & dados numéricos , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Esclera/cirurgia , Técnicas de Sutura
14.
Expert Rev Mol Diagn ; 16(5): 521-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26810587

RESUMO

Precision or personalized medicine through clinical genome and exome sequencing has been described by some as a revolution that could transform healthcare delivery, yet it is currently used in only a small fraction of patients, principally for the diagnosis of suspected Mendelian conditions and for targeting cancer treatments. Given the burden of illness in our society, it is of interest to ask how clinical genome and exome sequencing can be constructively integrated more broadly into the routine practice of medicine for the betterment of public health. In November 2014, 46 experts from academia, industry, policy and patient advocacy gathered in a conference sponsored by Illumina, Inc. to discuss this question, share viewpoints and propose recommendations. This perspective summarizes that work and identifies some of the obstacles and opportunities that must be considered in translating advances in genomics more widely into the practice of medicine.


Assuntos
Atenção à Saúde/organização & administração , Genoma Humano , Genômica/métodos , Medicina de Precisão/tendências , Atenção à Saúde/métodos , Testes Genéticos , Genômica/instrumentação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Kit de Reagentes para Diagnóstico
15.
J Hematol Oncol ; 8: 75, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26108208

RESUMO

Circulating tumor cells (CTCs) are cells shed from tumors or metastatic sites and are a potential biomarker for cancer diagnosis, management, and prognostication. The majority of current studies use single or infrequent CTC sampling points. This strategy assumes that changes in CTC number, as well as phenotypic and molecular characteristics, are gradual with time. In reality, little is known today about the actual kinetics of CTC dissemination and phenotypic and molecular changes in the blood of cancer patients. Herein, we show, using clinical case studies and hypothetical simulation models, how sub-optimal CTC sampling may result in misleading observations with clinical consequences, by missing out on significant CTC spikes that occur in between sampling times. Initial studies using highly frequent CTC sampling are necessary to understand the dynamics of CTC dissemination and phenotypic and molecular changes in the blood of cancer patients. Such an improved understanding will enable an optimal, study-specific sampling frequency to be assigned to individual research studies and clinical trials and better inform practical clinical decisions on cancer management strategies for patient benefits.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias/metabolismo , Células Neoplásicas Circulantes/metabolismo , Humanos , Células Neoplásicas Circulantes/patologia
16.
Cardiovasc Res ; 107(4): 546-55, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26092100

RESUMO

AIMS: During restenosis, vascular smooth muscle cells (VSMCs) migrate from the vascular media to the developing neointima. Preventing VSMC migration is therefore a therapeutic target for restenosis. Drugs, such as prostacyclin analogues, that increase the intracellular concentration of cyclic adenosine monophosphate (cAMP) can inhibit VSMC migration, but the mechanisms via which this occurs are unknown. Two main downstream mediators of cAMP are protein kinase A (PKA) and exchange protein directly activated by cAMP (Epac). This study has examined the effects of the prostacyclin analogue beraprost on VSMC migration and investigated the intracellular pathways involved. METHODS AND RESULTS: In a chemotaxis chamber, human saphenous vein VSMC migrated towards a platelet-derived growth-factor-BB (PDGF) chemogradient. Incubation with therapeutically relevant concentrations of cAMP-producing agonist beraprost significantly decreased PDGF-induced migration. Direct activation of either PKA or Epac inhibited migration whereas inhibition of PKA did not prevent the anti-migratory effect of beraprost. Direct activation of Epac also prevented hyperplasia in ex vivo serum-treated human veins. Using fluorescence resonance energy transfer, we demonstrated that beraprost activated Epac but not PKA. The mechanisms of this Epac-mediated effect involved activation of Rap1 with subsequent inhibition of RhoA. Cytoskeletal rearrangement at the leading edge of the cell was consequently inhibited. Interestingly, Epac1 was localized to the leading edge of migrating VSMC. CONCLUSIONS: These results indicate that therapeutically relevant concentrations of beraprost can inhibit VSMC migration via a previously unknown mechanism involving the cAMP mediator Epac. This may provide a novel target that could blunt neointimal formation.


Assuntos
Movimento Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , Epoprostenol/análogos & derivados , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Epoprostenol/farmacologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Pharmacol Res ; 95-96: 82-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25836919

RESUMO

In isolated guinea-pig ileum (GPI), the A1-adenosine acute withdrawal response is under the control of several neuronal signalling systems, including the µ/κ-opioid and the cannabinoid CB1 systems. It is now well established that after the stimulation of the A1-adenosine system, the indirect activation of both µ/κ-opioid and CB1 systems is prevented by the peptide cholecystokinin-8 (CCk-8). In the present study, we have investigated the involvement of the Ca(2+)/ATP-activated K(+) channels in the regulation of both acute A1-withdrawal and CCk-8-induced contractures in the GPI preparation. Interestingly, we found that: (a) the A1-withdrawal contracture is inhibited by voltage dependent Ca(2+)-activated K(+) channels, Kv, while it is enhanced by the voltage independent Ca(2+)-activated K(+) channels, SKCa; (b) in the presence of CCk-8, the inhibitory effect of the A1 agonist, CPA, on the peptide induced contracture is significantly enhanced by the voltage independent Ca(2+)-activated K(+) channel, SKCa; and (c) the A1-withdrawal contracture precipitated in the presence of CCk-8 is controlled by the ATP-sensitive potassium channels, KATP. Our data suggest, for the first time, that both Ca(2+)- and ATP-activated K(+) channels are involved in the regulation of both A1-withdrawal precipitated and CCk-8 induced contractures.


Assuntos
Colecistocinina/farmacologia , Íleo/efeitos dos fármacos , Canais KATP/metabolismo , Contração Muscular/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Canais de Potássio Cálcio-Ativados/metabolismo , Receptor A1 de Adenosina/metabolismo , Receptores Opioides/metabolismo , Síndrome de Abstinência a Substâncias/fisiopatologia , Agonistas do Receptor A1 de Adenosina/farmacologia , Antagonistas do Receptor A1 de Adenosina/farmacologia , Animais , Cobaias , Íleo/metabolismo , Íleo/fisiopatologia , Técnicas In Vitro , Masculino , Antagonistas de Entorpecentes/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Síndrome de Abstinência a Substâncias/metabolismo
18.
Mol Diagn Ther ; 18(4): 459-68, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24664550

RESUMO

BACKGROUND AND OBJECTIVES: Among patients with colorectal cancer (CRC), KRAS mutations were reported to occur in 30-51 % of all cases. CRC patients with KRAS mutations were reported to be non-responsive to anti-epidermal growth factor receptor (EGFR) monoclonal antibody (MoAb) treatment in many clinical trials. Hence, accurate detection of KRAS mutations would be critical in guiding the use of anti-EGFR MoAb therapies in CRC. METHODS: In this study, we carried out a detailed investigation of the efficacy of a wild-type (WT) blocking real-time polymerase chain reaction (PCR), employing WT KRAS locked nucleic acid blockers, and Sanger sequencing, for KRAS mutation detection in rare cells. Analyses were first conducted on cell lines to optimize the assay protocol which was subsequently applied to peripheral blood and tissue samples from patients with CRC. RESULTS: The optimized assay provided a superior sensitivity enabling detection of as little as two cells with mutated KRAS in the background of 10(4) WT cells (0.02 %). The feasibility of this assay was further investigated to assess the KRAS status of 45 colorectal tissue samples, which had been tested previously, using a conventional PCR sequencing approach. The analysis showed a mutational discordance between these two methods in 4 of 18 WT cases. CONCLUSION: Our results present a simple, effective, and robust method for KRAS mutation detection in both paraffin embedded tissues and circulating tumour cells, at single-cell level. The method greatly enhances the detection sensitivity and alleviates the need of exhaustively removing co-enriched contaminating lymphocytes.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Neoplásicas Circulantes/patologia , Proteínas ras/genética , Humanos , Mutação , Parafina , Inclusão em Parafina
19.
Appl Physiol Nutr Metab ; 37(3): 418-24, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22486379

RESUMO

Leg exercise hemodynamics during single-leg knee extensions were compared among healthy groups of early perimenopausal (n = 15), late perimenopausal (n = 12), and early postmenopausal (n = 11) women. Femoral blood flow (FBF) and vascular conductance (FVC) at rest and during very light work rates (0 and 5 W) were similar among all three menopause stage groups. Vascular responses at 10 W (FBF) and 20 W (FBF and FVC) were significantly higher (P < 0.05) in early perimenopausal compared with late perimenopausal women. At 15 and 25 W, FBF and FVC were similar between late perimenopausal and early postmenopausal groups but higher (P < 0.05) in early perimenopausal women as compared with the other two menopausal groups. In the combined sample of all three menopause stage groups, follicle-stimulating hormone was significantly correlated with vascular conductance during submaximal (15 W) exercise (R = -0.56, P < 0.001), even after adjustment for age, fitness, LDL cholesterol, and abdominal fat (R = -0.46, P = 0.005). Collectively, these findings suggest that in middle-aged women, there is an association between menopause stage and leg vascular responsiveness during exercise.


Assuntos
Exercício Físico/fisiologia , Menopausa/sangue , Vasodilatação/fisiologia , Adulto , Análise de Variância , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea/fisiologia , Estradiol/sangue , Teste de Esforço/métodos , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiologia , Hormônio Foliculoestimulante/sangue , Frequência Cardíaca/fisiologia , Humanos , Hiperemia/sangue , Articulação do Joelho/fisiologia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiologia , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Valores de Referência , Fluxo Sanguíneo Regional , Ultrassonografia Doppler , Saúde da Mulher
20.
Chemotherapy ; 57(1): 71-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21293121

RESUMO

OBJECTIVE: This phase II study was designed to evaluate the effects of vinorelbine (VRL) and capecitabine (CAP) as second-line combination chemotherapy in patients with advanced breast cancer (ABC) previously treated with anthracyclines and/or taxanes. METHODS: Treatment consisted of VRL 25 mg/m(2) administered on days 1 and 8 of a 21-day treatment cycle, along with oral CAP 825 mg/m(2) twice daily for 14 days, followed by 7 days of rest. RESULTS: 50 patients were enrolled and 48/50 (96.0%) patients were assessable for response. The median time to progression (TTP) and overall survival (OS) of the patients were 5.0 (95% confidence interval, CI, 2.1-7.9 months) and 12.0 months (95% CI, 8.0-16.0 months), respectively. The objective response rate was 26.0% (95% CI, 13.8-38.2%) with 1 confirmed complete response and 12 partial responses. The most frequent hematological adverse event was neutropenia of grade 3 and 4 in 5 (10.4%) and 2 patients (4.2%), respectively. Grade 3 stomatitis, asthenia, and diarrhea were observed in 1 (2.1%), 2 (4.2%) and 3 (6.3%) patients, respectively. CONCLUSION: The combination of VRL and CAP is feasible as second-line chemotherapy in patients with ABC previously treated with anthracyclines and/or taxanes, with efficacy being comparable to other available combination regimens.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Vimblastina/análogos & derivados , Adulto , Idoso , Antraciclinas/uso terapêutico , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Pessoa de Meia-Idade , Taxoides/uso terapêutico , Vimblastina/administração & dosagem , Vimblastina/uso terapêutico , Vinorelbina
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