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1.
Sleep Breath ; 25(1): 361-364, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32557244

RESUMO

PURPOSE: To determine the factors that sleep medicine/surgery fellowship program directors look for in applicants. METHODS: Program directors from 9 sleep medicine/surgery fellowship programs in the USA were sent an anonymous online survey. They were asked to select the five most important academic factors (of a list of 17) when evaluating potential fellowship candidates, then rank those five in order of importance. They were then asked to do the same for the most important subjective criteria (of a list of 12). RESULTS: Eight of 10 survey responses met inclusion criteria. Of the academic factors, strength of letters of recommendation, reputation of letter writer, and letters from sleep surgeons ranked highest. As for the subjective criteria, faculty assessment of the applicant on interview was ranked highest, followed by initiative and personality "fit" with the program. The reputation of an applicant's residency was ranked as more important than the reputation of their medical school. An applicant's performance in residency was assessed as more predictive of their performance in fellowship than performance during the interview process or position on the rank order list for the match. Only one program has a United States Medical Licensing Examination (USMLE) Step, and a different program has an Otolaryngology Training Examination (OTE) score cutoff. CONCLUSION: Letters of recommendation and interview are the most important factors in the selection process for hybrid sleep medicine and surgery fellowship programs, followed by research and residency program reputation. Sleep surgery-specific experience is helpful.


Assuntos
Bolsas de Estudo/organização & administração , Otolaringologia/educação , Critérios de Admissão Escolar , Medicina do Sono/educação , Bolsas de Estudo/métodos , Bolsas de Estudo/normas , Humanos , Otolaringologia/organização & administração , Otolaringologia/normas , Medicina do Sono/organização & administração , Medicina do Sono/normas , Inquéritos e Questionários , Estados Unidos
2.
EMBO Rep ; 17(4): 570-84, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26882547

RESUMO

Here, we show that miR-515-5p inhibits cancer cell migration and metastasis. RNA-seq analyses of both oestrogen receptor receptor-positive and receptor-negative breast cancer cells overexpressing miR-515-5p reveal down-regulation of NRAS, FZD4, CDC42BPA, PIK3C2B and MARK4 mRNAs. We demonstrate that miR-515-5p inhibits MARK4 directly 3' UTR interaction and that MARK4 knock-down mimics the effect of miR-515-5p on breast and lung cancer cell migration. MARK4 overexpression rescues the inhibitory effects of miR-515-5p, suggesting miR-515-5p mediates this process through MARK4 down-regulation. Furthermore, miR-515-5p expression is reduced in metastases compared to primary tumours derived from both in vivo xenografts and samples from patients with breast cancer. Conversely, miR-515-5p overexpression prevents tumour cell dissemination in a mouse metastatic model. Moreover, high miR-515-5p and low MARK4 expression correlate with increased breast and lung cancer patients' survival, respectively. Taken together, these data demonstrate the importance of miR-515-5p/MARK4 regulation in cell migration and metastasis across two common cancers.


Assuntos
Movimento Celular , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Metástase Neoplásica , Proteínas Serina-Treonina Quinases/genética , Células A549 , Animais , Apoptose , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo , Feminino , Humanos , Neoplasias Pulmonares/genética , Células MCF-7 , Camundongos , Invasividade Neoplásica , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , RNA Mensageiro
3.
Mol Cell Proteomics ; 14(5): 1201-16, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25693800

RESUMO

Current therapies for prostate cancer include antiandrogens, inhibitory ligands of the androgen receptor, which repress androgen-stimulated growth. These include the selective androgen receptor modulators cyproterone acetate and hydroxyflutamide and the complete antagonist bicalutamide. Their activity is partly dictated by the presence of androgen receptor mutations, which are commonly detected in patients who relapse while receiving antiandrogens, i.e. in castrate-resistant prostate cancer. To characterize the early proteomic response to these antiandrogens we used the LNCaP prostate cancer cell line, which harbors the androgen receptor mutation most commonly detected in castrate-resistant tumors (T877A), analyzing alterations in the proteome, and comparing these to the effect of these therapeutics upon androgen receptor activity and cell proliferation. The majority are regulated post-transcriptionally, possibly via nongenomic androgen receptor signaling. Differences detected between the exposure groups demonstrate subtle changes in the biological response to each specific ligand, suggesting a spectrum of agonistic and antagonistic effects dependent on the ligand used. Analysis of the crystal structures of the AR in the presence of cyproterone acetate, hydroxyflutamide, and DHT identified important differences in the orientation of key residues located in the AF-2 and BF-3 protein interaction surfaces. This further implies that although there is commonality in the growth responses between androgens and those antiandrogens that stimulate growth in the presence of a mutation, there may also be influential differences in the growth pathways stimulated by the different ligands. This therefore has implications for prostate cancer treatment because tumors may respond differently dependent upon which mutation is present and which ligand is activating growth, also for the design of selective androgen receptor modulators, which aim to elicit differential proteomic responses dependent upon cellular context.


Assuntos
Antagonistas de Androgênios/farmacologia , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/isolamento & purificação , Próstata/efeitos dos fármacos , Proteoma/isolamento & purificação , Receptores Androgênicos/química , Sequência de Aminoácidos , Antagonistas de Androgênios/química , Anilidas/química , Anilidas/farmacologia , Linhagem Celular Tumoral , Acetato de Ciproterona/química , Acetato de Ciproterona/farmacologia , Flutamida/análogos & derivados , Flutamida/química , Flutamida/farmacologia , Humanos , Masculino , Anotação de Sequência Molecular , Dados de Sequência Molecular , Mutação , Nandrolona/análogos & derivados , Nandrolona/química , Nandrolona/farmacologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Nitrilas/química , Nitrilas/farmacologia , Próstata/metabolismo , Próstata/patologia , Proteoma/genética , Proteoma/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais , Compostos de Tosil/química , Compostos de Tosil/farmacologia
4.
Carcinogenesis ; 37(1): 18-29, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26503968

RESUMO

Dickkopf-3 (Dkk-3) is a secreted protein whose expression is downregulated in many types of cancer. Endogenous Dkk-3 is required for formation of acini in 3D cultures of prostate epithelial cells, where it inhibits transforming growth factor (TGF)-ß/Smad signaling. Here, we examined the effects of Dkk-3 on the expression and activity of matrix metalloproteases (MMPs), which mediate the effects of TGF-ß on extracellular matrix disassembly during tissue morphogenesis and promote invasion of tumor cells. Silencing of Dkk-3 in prostate epithelial cells resulted in increased expression and enzyme activity of MMP-2 and MMP-9. Inhibition of MMP-9 partially restored normal acinar morphogenesis in Dkk-3-silenced RWPE-1 prostate epithelial cells. In PC3 prostate cancer cells, Dkk-3 inhibited TGF-ß-dependent migration and invasion. Inhibition was mediated by the Dkk-3 C-terminal cysteine-rich domain (Cys2), which also inhibited TGF-ß-induced expression of MMP9 and MMP13. In contrast, Dkk-3, but not Cys2, increased formation of normal acini in Dkk-3-silenced prostate epithelial cells. These observations highlight a role for Dkk-3 in modulating TGF-ß/MMP signals in the prostate, and suggest that the Dkk-3 Cys2 domain can be used as a basis for therapies that target the tumor promoting effects of TGF-ß signaling in advanced prostate cancer.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Fator de Crescimento Transformador beta/metabolismo , Células Acinares/metabolismo , Células Acinares/patologia , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Tumoral , Quimiocinas , Ativação Enzimática , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Morfogênese , Invasividade Neoplásica , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Estrutura Terciária de Proteína , Transdução de Sinais
5.
J Pathol ; 235(4): 581-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25408555

RESUMO

Biomechanical strain imposed by age-related thickening of the basal lamina and augmented tissue stiffness in the prostate gland coincides with increased cancer risk. Here we hypothesized that the structural alterations in the basal lamina associated with age can induce mechanotransduction pathways in prostate epithelial cells (PECs) to promote invasiveness and cancer progression. To demonstrate this, we developed a 3D model of PEC acini in which thickening and stiffening of basal lamina matrix was induced by advanced glycation end-product (AGE)-dependent non-enzymatic crosslinking of its major components, collagen IV and laminin. We used this model to demonstrate that antibody targeted blockade of CTLD2, the second of eight C-type lectin-like domains in Endo180 (CD280, CLEC13E, KIAA0709, MRC2, TEM9, uPARAP) that can recognize glycosylated collagens, reversed actinomyosin-based contractility [myosin-light chain-2 (MLC2) phosphorylation], loss of cell polarity, loss of cell-cell junctions, luminal infiltration and basal invasion induced by AGE-modified basal lamina matrix in PEC acini. Our in vitro results were concordant with luminal occlusion of acini in the prostate glands of adult Endo180(Δ) (Ex2-6/) (Δ) (Ex2-6) mice, with constitutively exposed CTLD2 and decreased survival of men with early (non-invasive) prostate cancer with high epithelial Endo180 expression and levels of AGE. These findings indicate that AGE-dependent modification of the basal lamina induces invasive behaviour in non-transformed PECs via a molecular mechanism linked to cancer progression. This study provides a rationale for targeting CTLD2 in Endo180 in prostate cancer and other pathologies in which increased basal lamina thickness and tissue stiffness are driving factors. © 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Membrana Basal/metabolismo , Movimento Celular , Células Epiteliais/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Lectinas de Ligação a Manose/metabolismo , Glicoproteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Mitogênicos/metabolismo , Animais , Membrana Basal/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Elasticidade , Humanos , Estimativa de Kaplan-Meier , Lectinas Tipo C/metabolismo , Masculino , Mecanotransdução Celular , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos Knockout , Invasividade Neoplásica , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estrutura Terciária de Proteína , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Fatores de Tempo
6.
J Cell Sci ; 126(Pt 8): 1858-67, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23444370

RESUMO

Loss of tissue organization is a hallmark of the early stages of cancer, and there is considerable interest in proteins that maintain normal tissue architecture. Prostate epithelial cells cultured in Matrigel form three-dimensional acini that mimic aspects of prostate gland development. The organization of these structures requires the tumor suppressor Dickkopf-3 (Dkk-3), a divergent member of the Dkk family of secreted Wnt signalling antagonists that is frequently downregulated in prostate cancer. To gain further insight into the function of Dkk-3 in the prostate, we compared the prostates of Dkk3-null mice with those of control littermates. We found increased proliferation of prostate epithelial cells in the mutant mice and changes in prostate tissue organization. Consistent with these observations, cell proliferation was elevated in acini formed by human prostate epithelial cells stably silenced for Dkk-3. Silencing of Dkk-3 increased TGF-ß/Smad signalling, and inhibitors of TGF-ß/Smad signalling rescued the defective acinar phenotype caused by loss of Dkk-3. These findings suggest that Dkk-3 maintains the structural integrity of the prostate gland by limiting TGF-ß/Smad signalling.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Morfogênese/fisiologia , Próstata/citologia , Próstata/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Western Blotting , Linhagem Celular , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Camundongos , Camundongos Knockout , Morfogênese/genética , Proteínas Smad/genética , Fator de Crescimento Transformador beta/genética
7.
Breast Cancer Res Treat ; 149(1): 59-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481644

RESUMO

Obesity is a known risk factor for breast cancer. We have recently identified that adipokine leptin regulates the expression of a proto-oncogenic enzyme sphingosine kinase 1 (SK1). Signal transducer and activator of transcription 3 (STAT3) has been linked to breast cancer progression and here we investigate the mechanism of leptin-induced STAT3 activation in ER-negative breast cancer. Gene and protein expression in human primary and secondary breast cancer tissues was analysed using quantitative real-time polymerase chain reaction (qRT-PCR) assay and immunofluorescence. Leptin-induced signalling was analysed in human ER-negative breast cancer cells using Western blotting, qRT-PCR and radiolabelling assays. Gene expression and receptor signalling was modified using small interfering RNA and neutralising antibodies. In human ER-negative breast tumours and lymph node metastases, the expression of leptin receptor significantly correlated with SK1. In ER-negative breast cancer cells, SK1 knockdown led to a significant reduction in leptin-induced STAT3 phosphorylation. Knockdown of another known activator of STAT3 signalling, gp130 also resulted in a significant decrease in leptin-induced STAT3 phosphorylation. ELISA assay showed that leptin produces a significant amount of IL-6 in an SK1-dependent manner. IL-6 neutralising antibodies significantly reduced p-STAT3. Immunofluorescent staining of human primary and secondary breast tumours showed significant correlation between SK1 and IL-6 (P < 0.001), SK1 and p-STAT3 (P < 0.01) and IL-6 and p-STAT3 (P < 0.01). Our findings demonstrate that leptin-induced STAT3 is partially cross activated through SK1-mediated IL6 secretion and gp130 activation. Positive correlations in human tissues suggest the potential significance of this pathway in ER-negative breast cancer.


Assuntos
Neoplasias da Mama/genética , Receptor gp130 de Citocina/biossíntese , Interleucina-6/biossíntese , Leptina/genética , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Fator de Transcrição STAT3/biossíntese , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Interleucina-6/genética , Metástase Linfática , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Receptores de Estrogênio/genética , Receptores para Leptina/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais , Ativação Transcricional/genética
8.
Sleep Breath ; 19(1): 205-12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24807119

RESUMO

PURPOSE: Conventional therapies for obstructive sleep apnea (OSA) are effective but suffer from poor patient adherence and may not fully alleviate major OSA-associated cardiovascular risk factors or improve certain aspects of quality of life. Predicting the onset of disordered breathing events in OSA patients may lead to improved strategies for treating OSA and inform our understanding of underlying disease mechanisms. In this work, we describe a deployable system capable of performing real-time predictions of sleep disordered breathing events in patients diagnosed with OSA, providing a novel approach for gaining insight into OSA pathophysiology, discovering population subgroups, and improving therapies. METHODS: LArge Memory STorage and Retrieval artificial neural networks with 864 different configurations were applied to polysomnogram records from 64 patients. Wavelet transforms, measures of entropy, and other statistics were applied to six physiological signals to provide network inputs. Approximate statistical tests were used to determine the best performing network for each patient. The most important predictors of disordered breathing events in OSA patients were determined by analyzing internal network parameters. RESULTS: The average optimized individual prediction sensitivity and specificity were 0.81 and 0.77, respectively. Predictions were better than random guessing for all OSA patients. Analysis of internal network parameters revealed a high degree of heterogeneity among disordered breathing event predictors and may reveal patient subgroups. CONCLUSIONS: We report the first practical system to predict individual disordered breathing events in a heterogeneous group of patients diagnosed with OSA. The pattern of disordered breathing predictors suggests variable underlying pathophysiological mechanisms and highlights the need for an individualized approach to OSA diagnosis, therapy, and management.


Assuntos
Técnicas de Apoio para a Decisão , Diagnóstico por Computador , Redes Neurais de Computação , Polissonografia , Processamento de Sinais Assistido por Computador , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Apneia Obstrutiva do Sono/classificação , Apneia Obstrutiva do Sono/fisiopatologia
9.
Breast Cancer Res ; 16(5): 426, 2014 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-25482303

RESUMO

INTRODUCTION: Obesity is a known risk factor for breast cancer. Sphingosine kinase 1 (SK1) is an oncogenic lipid kinase that is overexpressed in breast tumours and linked with poor prognosis, however, its role in obesity-driven breast cancer was never elucidated. METHODS: Human primary and secondary breast cancer tissues were analysed for SK1 and leptin receptor expression using quantitative real-time polymerase chain reaction (qRT-PCR) assay. Leptin-induced signalling was analysed in human oestrogen receptor (ER)-positive and negative breast cancer cells using Western blotting, qRT-PCR and radiolabelling assays. RESULTS: Our findings show for the first time that human primary breast tumours and associated lymph node metastases exhibit a strong correlation between SK1 and leptin receptor expression (Pearson R = 0.78 and R = 0.77, respectively, P <0.001). Both these genes are elevated in metastases of ER-negative patients and show a significant increase in patients with higher body mass index (BMI). Leptin induces SK1 expression and activation in ER-negative breast cancer cell lines MDAMB-231 and BT-549, but not in ER-positive cell lines. Pharmacological inhibition and gene knockdown showed that leptin-induced SK1 activity and expression are mediated by activation of extracellular signal-regulated kinases 1/2 (ERK1/2) and Src family kinase (SFK) pathways, but not by the major pathways downstream of leptin receptor (LEPR) - janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3). Src-homology 2 domain-containing phosphatase 2 (SHP2) appeared to be key to SK1 activation, and may function as an adaptor protein between SFKs and LEPR. Importantly, leptin-induced breast cancer cell proliferation was abrogated by SK1-specific small interfering RNA (siRNA). CONCLUSIONS: Overall, our findings demonstrate a novel SFK/ERK1/2-mediated pathway that links leptin signalling and expression of oncogenic enzyme SK1 in breast tumours and suggest the potential significance of this pathway in ER-negative breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Janus Quinase 2/metabolismo , Leptina/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Proliferação de Células , Indução Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Células MCF-7 , Obesidade/complicações , Obesidade/metabolismo , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Processamento de Proteína Pós-Traducional , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Receptores para Leptina/metabolismo , Transdução de Sinais , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quinases da Família src
10.
Blood ; 118(13): 3528-37, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21750319

RESUMO

The function of T-cell receptor (TCR) gene modified T cells is dependent on efficient surface expression of the introduced TCR α/ß heterodimer. We tested whether endogenous CD3 chains are rate-limiting for TCR expression and antigen-specific T-cell function. We show that co-transfer of CD3 and TCR genes into primary murine T cells enhanced TCR expression and antigen-specific T-cell function in vitro. Peptide titration experiments showed that T cells expressing introduced CD3 and TCR genes recognized lower concentration of antigen than T cells expressing TCR only. In vivo imaging revealed that TCR+CD3 gene modified T cells infiltrated tumors faster and in larger numbers, which resulted in more rapid tumor elimination compared with T cells modified by TCR only. After tumor clearance, TCR+CD3 engineered T cells persisted in larger numbers than TCR-only T cells and mounted a more effective memory response when rechallenged with antigen. The data demonstrate that provision of additional CD3 molecules is an effective strategy to enhance the avidity, anti-tumor activity and functional memory formation of TCR gene modified T cells in vivo.


Assuntos
Complexo CD3/fisiologia , Genes Codificadores dos Receptores de Linfócitos T/genética , Terapia Genética , Animais , Complexo CD3/genética , Complexo CD3/metabolismo , Células Cultivadas , Regulação para Baixo , Feminino , Terapia Genética/métodos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Linfoma de Células T/genética , Linfoma de Células T/patologia , Linfoma de Células T/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Resultado do Tratamento
11.
J Pathol ; 226(5): 775-83, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22072289

RESUMO

Cellular niches in adult tissue can harbour dysregulated microenvironments that become the driving force behind disease progression. The major environmental change when metastatic cells arrive in the bone is the destruction of mineralized type I collagen matrix. Once metastatic niches establish in bone, the invading tumour cells initiate a vicious cycle of osteolytic lesion formation via the dysregulation of paracrine signals and uncoupling of normal bone resorption and production. Here we report that the collagen receptor Endo180 (CD280, MRC2, uPARAP) participates in collagen deposition by primary human osteoblasts during de novo osteoid formation. This newly recognized function of Endo180 was suppressed in osteoblasts following heterotypic direct cell-cell contact in co-culture with prostate tumour cells. Reciprocal Endo180 up-regulation in osteolytic prostate tumour cells (PC3 and DU145) followed their direct contact with osteoblasts and promoted de novo collagen internalization, which is a previously characterized function of the constitutively recycling Endo180 receptor. The osteoblastic suppression and tumour cell-associated enhancement of Endo180 expression were equally sustained in these direct co-cultures. These findings are the first to demonstrate that increased tumour cell participation in collagen degradation and decreased collagen formation by osteoblasts in the osteolytic microenvironment are linked to the divergent regulation of a collagen-binding receptor. Immunohistochemical analysis of core biopsies from bone metastasis revealed higher levels of Endo180 expression in tumour cell foci than cells in the surrounding stroma. Additional experiments in prostate cell-osteoblast co-cultures indicate that divergent regulation of Endo180 is the result of dysregulated TGFß1 signalling. The findings of this study provide a rationale for targeting collagen remodelling by Endo180 in bone metastases and other collagen matrix pathologies.


Assuntos
Neoplasias Ósseas/metabolismo , Colágeno Tipo I/metabolismo , Lectinas de Ligação a Manose/metabolismo , Glicoproteínas de Membrana/metabolismo , Osteoblastos/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Mitogênicos/metabolismo , Células Estromais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Comunicação Autócrina , Biópsia , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Linhagem Celular Tumoral , Técnicas de Cocultura , Imunofluorescência , Humanos , Imuno-Histoquímica , Masculino , Lectinas de Ligação a Manose/genética , Glicoproteínas de Membrana/genética , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Comunicação Parácrina , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Superfície Celular/genética , Receptores Mitogênicos/genética , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Células Estromais/efeitos dos fármacos , Células Estromais/patologia , Transfecção , Microambiente Tumoral
12.
Int J Cancer ; 131(6): E872-83, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22539113

RESUMO

Glycogen synthase kinase (GSK-3) is upregulated in many types of tumor, including prostate cancer. GSK-3 inhibitors reduce prostate tumor cell growth; however, it is not clear if both isoforms, GSK-3α and GSK-3ß, are involved. Here, we compared their expression in prostate tumors and used gene silencing to study their functions in 22Rv1 prostate cancer cells. Compared to normal prostate, GSK-3α and GSK-3ß were upregulated in 25/79 and 24/79 cases of prostate cancer, respectively, with GSK-3α elevated in low Gleason sum score tumors and GSK-3ß expressed in high Gleason tumors, and both isoforms correlating with high expression of the androgen receptor (AR). Gene silencing of GSK-3α and, to a lesser extent, GSK-3ß reduced AR transcriptional activity. In addition, silencing of GSK-3ß, but not GSK-3α, reduced Akt phosphorylation. Acute and chronic silencing of either isoform reduced 22Rv1 growth in colony formation assays; however, this did not correlate with effects on AR activity. The GSK-3 inhibitor CHIR99021 reduced 22Rv1 colony formation by 50% in normal growth medium and by 15% in hormone-depleted medium, suggesting that GSK-3 is required both for hormone-dependent and hormone-independent proliferation. In addition, CHIR99021 enhanced growth inhibition by the AR antagonists bicalutamide and MDV3100. Finally, expression of GSK3A and GSK3B mRNAs correlated with a gene expression signature for androgen-regulated genes. Our observations highlight the importance of the GSK-3/AR signaling axis in prostate cancer and support the case for development of isoform-specific GSK-3 inhibitors and their use, in combination with AR antagonists, to treat patients with prostate cancer.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias da Próstata/enzimologia , Antagonistas de Androgênios/farmacologia , Linhagem Celular Tumoral , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Humanos , Masculino , Gradação de Tumores , Fosforilação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , RNA Mensageiro/análise
13.
BJU Int ; 109(12): 1801-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21933331

RESUMO

UNLABELLED: What's known on the subject? and What does the study add? Recent studies have demonstrated the efficacy of various new treatments. These have been in diverse areas of therapeutics research, including immunology and targeted biological therapy, as well as in new ways of approaching hormone refractory disease. The present paper seeks to review all of the key advances that have been reported in late-stage clinical studies and place them into the context of managing patients with advanced prostate cancer. OBJECTIVE: • To describe some of the most exciting late stage clinical developments in the field of new therapies for advanced prostate cancer. METHODS: • Pubmed was searched for articles pertaining to prostate cancer therapeutics clinical trials in the last 3 years. RESULTS: • Key positive trials in the areas of androgen resistance, tumour immunology, molecularly targeted agents and cytotoxics were reviewed and discussed in the context of metastatic prostate cancer. CONCLUSION: • Treatments emerging from these areas of scientific endeavour are progressing into clinical trials and are both good cause for hope in patients, and excellent examples of mechanism based drug discovery.


Assuntos
Antineoplásicos/uso terapêutico , Descoberta de Drogas/métodos , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Antagonistas de Androgênios/uso terapêutico , Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Vacinas Anticâncer/uso terapêutico , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Terapia de Alvo Molecular
14.
Proc Natl Acad Sci U S A ; 106(37): 15732-7, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19706389

RESUMO

Following estrogenic activation, the estrogen receptor-alpha (ERalpha) directly regulates the transcription of target genes via DNA binding. MicroRNAs (miRNAs) modulated by ERalpha have the potential to fine tune these regulatory systems and also provide an alternate mechanism that could impact on estrogen-dependent developmental and pathological systems. Through a microarray approach, we identify the subset of microRNAs (miRNAs) modulated by ERalpha, which include upregulation of miRNAs derived from the processing of the paralogous primary transcripts (pri-) mir-17-92 and mir-106a-363. Characterization of the mir-17-92 locus confirms that the ERalpha target protein c-MYC binds its promoter in an estrogen-dependent manner. We observe that levels of pri-mir-17-92 increase earlier than the mature miRNAs derived from it, implicating precursor cleavage modulation after transcription. Pri-mir-17-92 is immediately cleaved by DROSHA to pre-miR-18a, indicating that its regulation occurs during the formation of the mature molecule from the precursor. The clinical implications of this novel regulatory system were confirmed by demonstrating that pre-miR-18a was significantly upregulated in ERalpha-positive compared to ERalpha-negative breast cancers. Mechanistically, miRNAs derived from these paralogous pri-miRNAs (miR-18a, miR-19b, and miR-20b) target and downregulate ERalpha, while a subset of pri-miRNA-derived miRNAs inhibit protein translation of the ERalpha transcriptional p160 coactivator, AIB1. Therefore, different subsets of miRNAs identified act as part of a negative autoregulatory feedback loop. We propose that ERalpha, c-MYC, and miRNA transcriptional programs invoke a sophisticated network of interactions able to provide the wide range of coordinated cellular responses to estrogen.


Assuntos
Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Estradiol/farmacologia , Feminino , Humanos , Processamento Pós-Transcricional do RNA , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
15.
Immunol Cell Biol ; 89(2): 268-74, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20661259

RESUMO

Toll-like receptors (TLRs) lie in the core of resistance to infectious diseases allowing host immune cells to specifically detect pathogens by recognising their specific molecular patterns. Cell membrane-associated TLR4 (recognises lipopolysaccharide (LPS) of Gram-negative bacteria) and endosomal TLR7/8 (recognise viral single-stranded RNA) are known to activate hypoxia inducible factor-1α (HIF-1α) protein (necessary for cellular adaptation to the inflammatory stress) via redox-dependent mechanism. TLR4 triggers the cross talk between HIF-1α and apoptosis signal-regulating kinase 1 (ASK1), whereas TLR7/8 activates HIF-1α in the ASK1-independent manner. Here, we report that in THP-1 and RAW264.7 macrophages, ligand-induced activation of the TLR4 but not TLR7/8 induces activation and transcriptional upregulation of sphingosine kinase 1 (SphK1) in extracellular signal-regulating kinase and phospholipase C-1γ/PI3 kinase-dependent manner. TLR4-mediated SphK1 activation was found to be critical for the redox-dependent activation of HIF-1α and ASK1, as well as for the prevention of LPS-induced activation of caspase 3 and the expression of pro-inflammatory cytokine interleukin-6.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-6/biossíntese , Lipopolissacarídeos/farmacologia , MAP Quinase Quinase Quinase 5/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Sinalização do Cálcio/efeitos dos fármacos , Caspase 3/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Modelos Biológicos
16.
Am J Respir Crit Care Med ; 181(7): 727-33, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20019342

RESUMO

RATIONALE: The prediction of individual episodes of apnea and hypopnea in people with obstructive sleep apnea syndrome has not been thoroughly investigated. Accurate prediction of these events could improve clinical management of this prevalent disease. OBJECTIVES: To evaluate the performance of a system developed to predict episodes of obstructive apnea and hypopnea in individuals with obstructive sleep apnea; to determine the most important signals for making accurate and reliable predictions. METHODS: We employed LArge Memory STorage And Retrieval (LAMSTAR) artificial neural networks to predict apnea and hypopnea. Wavelet transform-based preprocessing was applied to six physiological signals obtained from a set of polysomnography studies and used to train and test the networks. MEASUREMENTS AND MAIN RESULTS: We tested prediction performance during non-REM and REM sleep as a function of data segment duration and prediction lead time. Measurements included average sensitivities, specificities, positive predictive values, and negative predictive values. Prediction performed best during non-REM sleep, using 30-second segments to predict events up to 30 seconds into the future. Most events were correctly predicted up to 60 seconds in the future. Apnea prediction achieved a sensitivity and specificity up to 80.6 +/- 5.6 and 72.8 +/- 6.6%, respectively. Hypopnea prediction achieved a sensitivity and specificity up to 74.4 +/- 5.9 and 68.8 +/- 7.0%., respectively. CONCLUSIONS: We report, to our knowledge, the first system to predict individual episodes of apnea and hypopnea. The most important signal for apnea prediction was submental electromyography. The most important signals for hypopnea prediction were submental electromyography and heart rate variability. This prediction system may facilitate improved therapies for obstructive sleep apnea.


Assuntos
Eletrodiagnóstico/métodos , Redes Neurais de Computação , Polissonografia/métodos , Síndromes da Apneia do Sono/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/fisiopatologia , Fases do Sono
17.
Ann Otol Rhinol Laryngol ; 130(4): 370-376, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32862654

RESUMO

OBJECTIVE: To compare patients with moderate-severe obstructive sleep apnea (OSA) undergoing traditional single and multilevel sleep surgery to those undergoing upper airway stimulation (UAS). STUDY DESIGN: Case control study comparing retrospective cohort of patients undergoing traditional sleep surgery to patients undergoing UAS enrolled in the ADHERE registry. SETTING: 8 multinational academic medical centers. SUBJECTS AND METHODS: 233 patients undergoing prior single or multilevel traditional sleep surgery and meeting study inclusion criteria were compared to 465 patients from the ADHERE registry who underwent UAS. We compared preoperative and postoperative demographic, quality of life, and polysomnographic data. We also evaluated treatment response rates. RESULTS: The pre and postoperative apnea hypopnea index (AHI) was 33.5 and 15 in the traditional sleep surgery group and 32 and 10 in the UAS group. The postoperative AHI in the UAS group was significantly lower. The pre and postoperative Epworth sleepiness scores (ESS) were 12 and 6 in both the traditional sleep surgery and UAS groups. Subgroup analysis evaluated those patients undergoing single level palate and multilevel palate and tongue base traditional sleep surgeries. The UAS group had a significantly lower postoperive AHI than both traditional sleep surgery subgroups. The UAS group had a higher percentage of patients reaching surgical success, defined as a postoperative AHI <20 with a 50% reduction from preoperative severity. CONCLUSION: UAS offers significantly better control of AHI severity than traditional sleep surgery. Quality life improvements were similar between groups.


Assuntos
Terapia por Estimulação Elétrica , Procedimentos Cirúrgicos Otorrinolaringológicos , Complicações Pós-Operatórias , Qualidade de Vida , Apneia Obstrutiva do Sono , Manuseio das Vias Aéreas/métodos , Estudos de Casos e Controles , Pesquisa Comparativa da Efetividade , Terapia por Estimulação Elétrica/efeitos adversos , Terapia por Estimulação Elétrica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos/efeitos adversos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Palato/cirurgia , Polissonografia/métodos , Polissonografia/estatística & dados numéricos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Língua/cirurgia
18.
Laryngoscope ; 131(7): 1676-1682, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33443811

RESUMO

OBJECTIVES/HYPOTHESIS: To determine the association between findings of blinded reviews of preoperative drug-induced sleep endoscopy (DISE) and outcomes of hypoglossal nerve stimulation (HNS) for obstructive sleep apnea (OSA). STUDY DESIGN: Cohort study. METHODS: A retrospective, multicenter cohort study of 343 adults who underwent treatment of OSA with HNS from 10 academic medical centers was performed. Preoperative DISE videos were scored by four blinded reviewers using the VOTE Classification and evaluation of a possible primary structure contributing to airway obstruction. Consensus DISE findings were examined for an association with surgical outcomes based on therapy titration polysomnogram (tPSG). Treatment response was defined by a decrease of ≥50% in the apnea-hypopnea index (AHI) to <15 events/hour. RESULTS: Study participants (76% male, 60.4 ± 11.0 years old) had a body mass index of 29.2 ± 3.6 kg/m2 . AHI decreased (35.6 ± 15.2 to 11.0 ± 14.1 events/hour; P < .001) on the tPSG, with a 72.6% response rate. Complete palate obstruction (vs. none) was associated with the greatest difference in AHI improvement (-26.8 ± 14.9 vs. -19.2 ± 12.8, P = .02). Complete (vs. partial/none) tongue-related obstruction was associated with increased odds of treatment response (78% vs. 68%, P = .043). Complete (vs. partial/none) oropharyngeal lateral wall-related obstruction was associated with lower odds of surgical response (58% vs. 74%, P = .042). CONCLUSIONS: The DISE finding of primary tongue contribution to airway obstruction was associated with better outcomes, whereas the opposite was true for the oropharyngeal lateral walls. This study suggests that the role for DISE in counseling candidates for HNS extends beyond solely for excluding complete concentric collapse related to the velum. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:1676-1682, 2021.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Terapia por Estimulação Elétrica/métodos , Endoscopia/métodos , Nervo Hipoglosso , Apneia Obstrutiva do Sono/terapia , Idoso , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/terapia , Contraindicações de Procedimentos , Aconselhamento , Terapia por Estimulação Elétrica/efeitos adversos , Terapia por Estimulação Elétrica/instrumentação , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Neuroestimuladores Implantáveis , Masculino , Pessoa de Meia-Idade , Orofaringe/diagnóstico por imagem , Palato/diagnóstico por imagem , Polissonografia , Período Pré-Operatório , Estudos Retrospectivos , Índice de Gravidade de Doença , Sono/efeitos dos fármacos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Língua/diagnóstico por imagem , Resultado do Tratamento
19.
Mol Cancer ; 9: 55, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20219091

RESUMO

BACKGROUND: Wnt-11 is a secreted protein that modulates cell growth, differentiation and morphogenesis during development. We previously reported that Wnt-11 expression is elevated in hormone-independent prostate cancer and that the progression of prostate cancer from androgen-dependent to androgen-independent proliferation correlates with a loss of mutual inhibition between Wnt-11- and androgen receptor-dependent signals. However, the prevalence of increased expression of Wnt-11 in patient tumours and the functions of Wnt-11 in prostate cancer cells were not known. RESULTS: Wnt-11 protein levels in prostate tumours were determined by immunohistochemical analysis of prostate tumour tissue arrays. Wnt-11 protein was elevated in 77/117 of tumours when compared with 27 benign prostatic hypertrophy specimens and was present in 4/4 bone metastases. In addition, there was a positive correlation between Wnt-11 expression and PSA levels above 10 ng/ml. Androgen-depleted LNCaP prostate cancer cells form neurites and express genes associated with neuroendocrine-like differentiation (NED), a feature of prostate tumours that have a poor prognosis. Since androgen-depletion increases expression of Wnt-11, we examined the role of Wnt-11 in NED. Ectopic expression of Wnt-11 induced expression of NSE and ASCL1, which are markers of NED, and this was prevented by inhibitors of cyclic AMP-dependent protein kinase, consistent with the known role of this kinase in NED. In contrast, Wnt-11 did not induce NSE expression in RWPE-1 cells, which are derived from benign prostate, suggesting that the role of Wnt-11 in NED is specific to prostate cancer. In addition, silencing of Wnt-11 expression in androgen-depleted LNCaP cells prevented NED and resulted in apoptosis. Silencing of Wnt-11 gene expression in androgen-independent PC3 cells also reduced expression of NSE and increased apoptosis. Finally, silencing of Wnt-11 reduced PC3 cell migration and ectopic expression of Wnt-11 promoted LNCaP cell invasion. CONCLUSIONS: These observations suggest that the increased level of Wnt-11 found in prostate cancer contributes to tumour progression by promoting NED, tumour cell survival and cell migration/invasion, and may provide an opportunity for novel therapy in prostate cancer.


Assuntos
Diferenciação Celular , Movimento Celular , Células Neuroendócrinas/patologia , Neoplasias da Próstata/patologia , Proteínas Wnt/metabolismo , Androgênios/deficiência , Androgênios/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Masculino , Invasividade Neoplásica , Células Neuroendócrinas/efeitos dos fármacos , Células Neuroendócrinas/metabolismo , Neoplasias da Próstata/genética , Proteínas Wnt/genética
20.
Breast Cancer Res Treat ; 124(2): 543-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20535545

RESUMO

Weight gain in women receiving chemotherapy for breast cancer is associated with a higher risk of recurrence. Using metabonomic profiling, we recently reported that plasma lactate and alanine were prognostic for weight gain in individuals with breast cancer receiving chemotherapy. The role of lipid second messengers has not been studied. We assessed serum levels of sphingosine-1-phosphate (S1P), a known secreted lipid second messenger with a role in cell growth, in sequential samples from post-menopausal women receiving standard chemotherapy for early breast cancer and correlated these with body mass measurements and metabonomic profiling. While serum S1P levels prior to treatment did not correlate with body weight changes or circulating alanine and lactate, S1P levels measured during therapy were inversely correlated with weight gain (P = 0.04), but not weight loss (P = 0.74) or no change in weight (P = 0.5), suggesting a role of dynamic circulating S1P in adipocyte growth. These data provide evidence for an association between serum S1P and weight gain during chemotherapy cycles in women with breast cancer. Lipid second messengers have a role in chemotherapy-induced weight gain in breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Lisofosfolipídeos/sangue , Esfingosina/análogos & derivados , Aumento de Peso/efeitos dos fármacos , Biomarcadores/sangue , Índice de Massa Corporal , Neoplasias da Mama/sangue , Quimioterapia Adjuvante , Regulação para Baixo , Feminino , Humanos , Metabolômica , Terapia Neoadjuvante , Medição de Risco , Fatores de Risco , Esfingosina/sangue , Fatores de Tempo , Resultado do Tratamento
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