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1.
Eur J Cancer Care (Engl) ; 27(4): e12857, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29767417

RESUMO

This study examined concordances of cancer patients' received and caregivers' provided support and dyadic relationship quality, and their predictive utility in prospective psychological distress and well-being. A total of 83 Chinese cancer patient-caregiver dyads were recruited in two government-funded hospitals in Hong Kong. Participants reported received (patient)/provided (caregiver) emotional and instrumental support and dyadic relationship quality within 6 months after diagnosis (T1), and anxiety and depressive symptoms, positive affect and life satisfaction at both T1 and 6-month follow-up (T2). We hypothesised that concordances at T1 would predict lower psychological distress and higher psychological well-being among both patients and caregivers at T2. Concordances were indicated by Gwet's AC2 scores (possible range = -1.00 to 1.00) and as follows: emotional support: M = 0.92, SD = 0.12, range = 0.25-1.00; instrumental support: M = 0.92, SD = 0.16, range = 0.08-1.00; and relationship quality: M = 0.63, SD = 0.27, range = -0.31 to 1.00. Hierarchical multiple regressions revealed that T1 concordances of perceived emotional and instrumental support and dyadic relationship quality positively predicted T2 anxiety symptoms [F(9, 74) = 6.725, ∆R2  = .031, p < .001)] and state positive affect [F(9, 74) = 3.436, ∆R2  = .042, p = .001)], whereas inversely predicted T2 depressive symptoms [F(9, 74) = 4.189, ∆R2  = .042, p < .01)]. Significant associations were found only among caregivers, but not patients.


Assuntos
Ansiedade/psicologia , Cuidadores/psicologia , Depressão/psicologia , Relações Interpessoais , Neoplasias/enfermagem , Apoio Social , Estresse Psicológico/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hong Kong , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Neoplasias/psicologia , Adulto Jovem
2.
Oncogene ; 32(18): 2282-91, 2291.e1-7, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-22797075

RESUMO

Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is expressed in the epithelial cells of a wide range of organs/tissues from which most cancers are derived. Although accumulating reports have indicated the association of cancer incidence with genetic variations in CFTR gene, the exact role of CFTR in cancer development and the possible underlying mechanism have not been elucidated. Here, we report that CFTR expression is significantly decreased in both prostate cancer cell lines and human prostate cancer tissue samples. Overexpression of CFTR in prostate cancer cell lines suppresses tumor progression (cell growth, adhesion and migration), whereas knockdown of CFTR leads to enhanced malignancies both in vitro and in vivo. In addition, we demonstrate that CFTR knockdown-enhanced cell proliferation, cell invasion and migration are significantly reversed by antibodies against either urokinase plasminogen activator (uPA) or uPA receptor (uPAR), which are known to be involved in various malignant traits of cancer development. More interestingly, overexpression of CFTR suppresses uPA by upregulating the recently described tumor suppressor microRNA-193b (miR-193b), and overexpression of pre-miR-193b significantly reverses CFTR knockdown-enhanced malignant phenotype and abrogates elevated uPA activity in prostate cancer cell line. Finally, we show that CFTR gene transfer results in significant tumor repression in prostate cancer xenografts in vivo. Taken together, the present study has demonstrated a previously undefined tumor-suppressing role of CFTR and its involvement in regulation of miR-193b in prostate cancer development.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neoplasias da Próstata/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/imunologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Oncogene ; 29(40): 5475-89, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20661220

RESUMO

Minichromosome maintenance (MCM) proteins 2-7 are important in DNA replication licensing. Functional roles beyond licensing are speculated. In addition, significances in medulloblastoma (MB) remain unclear. In this study, we showed the frequent deregulation of MCM2 and MCM3 expression in 7 MB cell lines and 31 clinical samples. Moreover, DAOY and ONS76 and the clinical samples expressed elevated MCM7 transcripts with genomic gain of the gene. Immunopositivity restricted to tumor cells was found in 41, 37 and 53 out of 73 MB cases for MCM2, MCM3 and MCM7, respectively. High-MCM3 expression was associated with poor prognosis. Knockdowns of these MCMs significantly inhibited anchorage-dependent and -independent MB cell growth. The inhibition of MCM3 expression by small interfering RNA knockdown was related to G1 arrest with reduced cyclin A expression, whereas the MCM2- and MCM7-knocked-down cells arrested at G2/M with increased cyclin A expression. Interestingly, we demonstrated the links of these MCMs with cell migration and invasion using wound-healing and Transwell migration/invasion assays. Exogenous overexpression of MCM2, MCM3 and MCM7 increased anchorage-independent cell growth, and also cell migration and invasion capabilities in MB cells. The knockdown reduced the number of filopodial cells and the cells with intense stress fibers by blocking cdc42 and Rho activation. Taken together, deregulation of MCM2, MCM3 and MCM7 expression might be involved in MB tumorigenesis and we revealed undefined roles of these MCMs in control of MB cell migration and invasion.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Movimento Celular/genética , Proteínas de Ligação a DNA/metabolismo , Meduloblastoma/metabolismo , Proteínas Nucleares/metabolismo , Biomarcadores Tumorais/análise , Proteínas de Ciclo Celular/genética , Separação Celular , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Hibridização Genômica Comparativa , Proteínas de Ligação a DNA/genética , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Meduloblastoma/genética , Meduloblastoma/patologia , Componente 2 do Complexo de Manutenção de Minicromossomo , Componente 3 do Complexo de Manutenção de Minicromossomo , Componente 7 do Complexo de Manutenção de Minicromossomo , Invasividade Neoplásica/genética , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Cell Death Differ ; 17(9): 1511-23, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20203690

RESUMO

G-protein-coupled receptor-30 (GPR30) shows estrogen-binding affinity and mediates non-genomic signaling of estrogen to regulate cell growth. We here showed for the first time, in contrast to the reported promoting action of GPR30 on the growth of breast and ovarian cancer cells, that activation of GPR30 by the receptor-specific, non-estrogenic ligand G-1 inhibited the growth of androgen-dependent and androgen-independent prostate cancer (PCa) cells in vitro and PC-3 xenografts in vivo. However, G-1 elicited no growth or histological changes in the prostates of intact mice and did not inhibit growth in quiescent BPH-1, an immortalized benign prostatic epithelial cell line. Treatment of PC-3 cells with G-1 induced cell-cycle arrest at the G(2) phase and reduced the expression of G(2)-checkpoint regulators (cyclin-A2, cyclin-B1, cdc25c, and cdc2) and phosphorylation of their common transcriptional regulator NF-YA in PC-3 cells. With extensive use of siRNA-knockdown experiments and the MEK inhibitor PD98059 in this study, we dissected the mechanism underlying G-1-induced inhibition of PC-3 cell growth, which was mediated through GPR30, followed by sustained activation of Erk1/2 and a c-jun/c-fos-dependent upregulation of p21, resulting in the arrest of PC-3 growth at the G(2) phase. The discovery of this signaling pathway lays the foundation for future development of GPR30-based therapies for PCa.


Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fase G2/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Animais , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Ciclopentanos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Quinolinas/farmacologia , RNA Interferente Pequeno/genética , Receptores de Estrogênio/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Phytother Res ; 22(10): 1384-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18570234

RESUMO

Fructus Corni, Fructus Schisandrae Chinensis, Poria, Rhizoma Alismatis and Rhizoma Dioscoreae are commonly used in traditional Chinese medicine for diabetes treatment. They are also the component herbs of an antidiabetic foot ulcer formula with demonstrated clinical efficacy. Although some of these herbal extracts were previously shown to possess in vivo antidiabetic effects (i.e. lowering blood glucose levels), the underlying mechanisms remain elusive. The objective of this study is to investigate the possible antidiabetic mechanisms of these individual herbs, using a systematic study platform which includes four in vitro tissue models: glucose absorption into intestinal brush border membrane vesicles (BBMV), gluconeogenesis by rat hepatoma cell line H4IIE, glucose uptake by human skin fibroblasts cell line Hs68 and mouse adipocytes 3T3-L1. All tested herbs showed significant in vitro antidiabetic effects in at least two models. Fructus Schisandrae Chinensis, Poria, Rhizoma Alismatis and Rhizoma Dioscoreae showed significant inhibitory effects in the BBMV glucose uptake assay. All tested herbs showed significant stimulatory effects to the glucose uptake of Hs68 and 3T3-L1 cells, except Poria and Rhizoma Dioscoreae which were not effective to Hs68 and 3T3-L1 respectively. However, none of the tested herbs inhibited hepatic gluconeogenesis. In conclusion, the five herbs exhibited distinct antidiabetic mechanisms in vitro and hence our investigations provided scientific evidence to support the traditional usage of these herbs for diabetic treatment in medicinal formulae.


Assuntos
Medicamentos de Ervas Chinesas , Hipoglicemiantes/farmacologia , Células 3T3-L1 , Animais , Glicemia/análise , Linhagem Celular Tumoral , Gluconeogênese/efeitos dos fármacos , Humanos , Técnicas In Vitro , Camundongos , Ratos
7.
Phytomedicine ; 14(11): 778-84, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17298878

RESUMO

Cortex Moutan (CM, root bark of Paeonia suffruticosa Andr.) is one of the common herbs found in anti-diabetic traditional Chinese medicine formulae. To study the potential anti-diabetic mechanisms of CM, four in vitro models (intestinal brush border membrane vesicles (BBMV), rat hepatoma cell line H4IIE, human skin fibroblasts cell line Hs68 and mouse adipocytes 3T3-L1) were used. CM showed significant in vitro anti-diabetic effects by inhibiting glucose uptake of BBMV and enhancing glucose uptake into Hs68 and 3T3-L1 cells. Using bioassay-guided fractionation, paeonol was confirmed to be one of the active constituents for inhibiting BBMV glucose uptake. With neonatal-streptozotocin diabetic rats, paeonol (200 and 400mg/kgbody wt.) was found to improve oral glucose tolerance in vivo. To the best of our knowledge, this is the first report on the anti-diabetic effect of paeonol.


Assuntos
Hipoglicemiantes/farmacologia , Paeonia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Glicemia , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose/metabolismo , Teste de Tolerância a Glucose , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Ratos , Ratos Wistar , Estreptozocina
8.
Br J Cancer ; 96(4): 617-22, 2007 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-17262084

RESUMO

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus-associated disease with high prevalence in Southern Chinese. Using multiparametric flow cytometry, we identified significant expansions of circulating naïve and memory CD4+CD25(high) T cells in 56 NPC patients compared with healthy age- and sex-matched controls. These were regulatory T cells (Treg), as they overexpressed Foxp3 and GITR, and demonstrated enhanced suppressive activities against autologous CD4+CD25- T-cell proliferation in functional studies on five patients. Abundant intraepithelial infiltrations of Treg with very high levels of Foxp3 expression and absence of CCR7 expression were also detected in five primary tumours. Our current study is the first to demonstrate an expansion of functional Treg in the circulation of NPC patients and the presence of infiltrating Treg in the tumour microenvironment. As Treg may play an important role in suppressing antitumour immunity, our findings provide critical insights for clinical management of NPC.


Assuntos
Fatores de Transcrição Forkhead/biossíntese , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Nasofaríngeas/imunologia , Receptores de Fator de Crescimento Neural/biossíntese , Receptores do Fator de Necrose Tumoral/biossíntese , Linfócitos T Reguladores/imunologia , Proliferação de Células , Células Cultivadas , Citometria de Fluxo/métodos , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Humanos , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Estadiamento de Neoplasias , Sensibilidade e Especificidade
9.
J Ethnopharmacol ; 109(1): 10-20, 2007 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16891069

RESUMO

Complications of diabetes impose major public health burdens worldwide. The positive effect of a Radix Astragali-based herbal preparation on healing diabetic foot ulcers in patients has been reported. Formula 1 is also referred as the 'Herbal drink to strengthen muscle and control swelling'. This formula contains six Chinese medical herbs, including Radix Astragali, Radix Rehmanniae, Rhizoma Smilacis Chinensis, Rhizoma Atractylodis Macrocephalae, Radix Polygoni Multiflori Preparata, and Radix Stephania Tetrandrae. Three of these herbs (Radix Astragali, Radix Rehmanniae, Rhizoma Atractylodis Macrocephalae) are commonly used in different anti-diabetic formulae of Chinese medicine. The objective of the current study is to use an interdisciplinary approach to test the hypothesis that Formula 1 and its components influence tissue and systemic glucose homeostasis. In vitro and in vivo models have been established including: (1) glucose absorption into intestinal brush border membrane vesicles (BBMV); (2) gluconeogenesis by H4IIE hepatoma cells; (3) glucose uptake by 3T3-L1 adipocytes and Hs68 skin fibroblasts; (4) normalization of glycaemic control in a diabetic rat model. The results of in vitro studies indicated that all herbal extracts can modify cellular glucose homeostasis. Since Formula 1 and Rhizoma Smilacis Chinensis extracts demonstrated potent effects on modifying glucose homeostasis in multiple tissues in vitro, they were further studied for their anti-diabetic activities in vivo using a streptozotocin (STZ)-induced diabetic rat model. The results showed that Formula 1 and Rhizoma Smilacis Chinensis extracts did not significantly improve oral glucose tolerance or basal glycaemia in diabetic rats. In conclusion, the anti-diabetic foot ulcer Formula 1 contains ingredients active in modifying tissue glucose homeostasis in vitro but these biological activities could not be associated with improved glycaemic control of diabetes in vivo.


Assuntos
Pé Diabético/tratamento farmacológico , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Fitoterapia , Plantas Medicinais/química , Células 3T3 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Glicemia/metabolismo , Carcinoma Hepatocelular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Cultivadas , Desoxiglucose/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glucose/biossíntese , Teste de Tolerância a Glucose , Humanos , Camundongos , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Coelhos , Ratos , Ratos Wistar
10.
Ann Hematol ; 85(8): 535-41, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16710717

RESUMO

We performed a retrospective analysis on the human leukocyte antigen (HLA) data of 53 consecutive Chinese patients with high-risk childhood acute lymphoblastic leukemia (ALL) diagnosed from 1989 to 2003. A significantly higher frequency of HLA-B67 in the male relapse group of patients [OR, 23.08; 95% CI, 5.31-100.36; p = 0.0042; for statistical significance after Bonferroni correction (Bc) p (Bc) < 0.0083] was identified after Bonferroni correction. Although not surviving the Bonferroni correction, gender effects on the association were also observed with HLA-A11, HLA-A32, HLA-A33, and HLA-B22, which were however more prevalent in the female patients and particularly those developing relapse. Two patients with HLA-A29 and HLA-B7 revealed significantly shortened survivals, suggestive of their potential prognostic impacts. Notably, for the first time, we found a significant correlation of leukocyte count with HLA types, where HLA-A33 (p = 0.006) or HLA-B17 (p < 0.001) signifies higher leukocytosis at presentation. Taken together, our findings support the involvement of HLA in Chinese high-risk childhood ALL.


Assuntos
Biomarcadores Tumorais/sangue , Suscetibilidade a Doenças/sangue , Antígenos HLA-A/sangue , Antígenos HLA-B/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Adolescente , Adulto , Povo Asiático , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Hong Kong , Humanos , Leucocitose/sangue , Leucocitose/diagnóstico , Leucocitose/mortalidade , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prognóstico , Recidiva , Estudos Retrospectivos , Caracteres Sexuais
11.
J Urol ; 172(1): 331-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15201806

RESUMO

PURPOSE: Various strategies have recently emerged to improve the diagnostic prediction of prostate cancer (CaP). One such strategy includes the mass profiling of serum protein fractions selectively adsorbed onto chemically modified probes. In the current study we further validated this approach, while offering a more versatile, less expensive and yet equally predictive alternative to existing technologies. MATERIALS AND METHODS: A solid core lipophilic C-18 resin was used to extract and enrich the low molecular weight protein fraction from patient serum for further analysis by mass spectrometry. Mass spectra generated from a 48 patient training set were data mined using multivariate analysis to identify diagnostically significant protein peaks. These peaks were then used to test a blinded study set comprising 168 patients with common statistical algorithms and commercially available software packages. RESULTS: A total of 36 peaks generated from the training set were used to test the combined set of 168 serum samples obtained from 98 healthy individuals and 70 patients with CaP. We report a sensitivity of 94.1% and a specificity of 99.0% with 1 false-positive, 4 false-negative and 5 nondiagnosed cases. CONCLUSIONS: Our results further indicate that mass profiling of serological proteins provides a means for the accurate detection of CaP. In addition, our approach was found to be superior to chip based protocols, generating rich, sharp, highly reproducible spectra attainable in a high throughput manner and at minimal cost. This technique is also scaleable for subsequent protein characterization using multidimensional protein identification technologies. Finally, analyses of mass spectra with commercially available statistical applications was found to be highly effective in generating highly discriminatory m/z values for CaP diagnosis.


Assuntos
Biomarcadores Tumorais/análise , Proteínas Sanguíneas/análise , Neoplasias da Próstata/diagnóstico , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise Serial de Proteínas , Testes Sorológicos
12.
Br J Haematol ; 123(4): 637-45, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14616967

RESUMO

The methylation status, mutation and expression of RASSF1A, and mutations of RAS and BRAF were studied in 52 patients with multiple myeloma (MM), one plasma cell leukaemia (PCL) patient and four MM-derived cell lines. Aberrant methylation of RASSF1A was found in nine of 32 MM patients and in one of four MM cell lines (U266), where the associated loss of transcription was reversible by demethylation treatment. RASSF1A transcription was further investigated on anti-CD138-sorted plasma cell-enriched bone marrow samples from 10 MM, one PCL and three reactive plasmacytosis patients. While the wild-type RASSF1A transcript was detected in all three reactive plasmacytosis and the PCL samples, we found no detectable wild-type transcripts in six of 10 MM samples studied. In two MM samples, only the non-functional variant transcript was detected, whereas the other four showed loss of transcription. In great contrast to western data, RAS mutations were identified in only four of 31 (13%) MM patients. While no RASSF1A or BRAF mutation (V599E) was detected in any of the primary MM studied (n = 21), the latter was found in the U266 cell line. Taken together, these data indicate that alterations of RAS signalling are critical in MM pathogenesis. In our current studies of Chinese MM patients, these alterations involved frequent RASSF1A inactivation (60%) as a result of transcriptional silencing or expression of a non-functional variant transcript.


Assuntos
Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/genética , Proteínas Oncogênicas/genética , Transdução de Sinais , Proteínas Supressoras de Tumor , Proteínas ras/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , China , Metilação de DNA , Análise Mutacional de DNA/métodos , Feminino , Expressão Gênica , Inativação Gênica , Genes Supressores de Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA/métodos , Transcrição Gênica
13.
Am J Pathol ; 159(1): 79-92, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438457

RESUMO

An antibody, GC-17, thoroughly characterized for its specificity for estrogen receptor-beta (ER-beta), was used to immunolocalize the receptor in histologically normal prostate, prostatic intraepithelial neoplasia, primary carcinomas, and in metastases to lymph nodes and bone. Comparisons were made between ER-beta, estrogen receptor-alpha (ER-alpha), and androgen receptor (AR) immunostaining in these tissues. Concurrently, transcript expression of the three steroid hormone receptors was studied by reverse transcriptase-polymerase chain reaction analysis on laser capture-microdissected samples of normal prostatic acini, dysplasias, and carcinomas. In Western blot analyses, GC-17 selectively identified a 63-kd protein expressed in normal and malignant prostatic epithelial cells as well as in normal testicular and prostatic tissues. This protein likely represents a posttranslationally modified form of the long-form ER-beta, which has a predicted size of 59 kd based on polypeptide length. In normal prostate, ER-beta immunostaining was predominately localized in the nuclei of basal cells and to a lesser extent stromal cells. ER-alpha staining was only present in stromal cell nuclei. AR immunostaining was variable in basal cells but strongly expressed in nuclei of secretory and stromal cells. Overall, prostatic carcinogenesis was characterized by a loss of ER-beta expression at the protein and transcript levels in high-grade dysplasias, its reappearance in grade 3 cancers, and its diminution/absence in grade 4/5 neoplasms. In contrast, AR was strongly expressed in all grades of dysplasia and carcinoma. Because ER-beta is thought to function as an inhibitor of prostatic growth, androgen action, presumably mediated by functional AR and unopposed by the beta receptor, may have provided a strong stimulus for aberrant cell growth. With the exception of a small subset of dysplasias in the central zone and a few carcinomas, ER-alpha-stained cells were not found in these lesions. The majority of bone and lymph node metastases contained cells that were immunostained for ER-beta. Expression of ER-beta in metastases may have been influenced by the local microenvironment in these tissues. In contrast, ER-alpha-stained cells were absent in bone metastases and rare in lymph nodes metastases. Irrespective of the site, AR-positive cells were found in all metastases. Based on our recent finding of anti-estrogen/ER-beta-mediated growth inhibition of prostate cancer cells in vitro, the presence of ER-beta in metastatic cells may have important implications for the treatment of late-stage disease.


Assuntos
Carcinoma/metabolismo , Próstata/metabolismo , Doenças Prostáticas/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Idoso , Western Blotting , Carcinoma/patologia , Carcinoma/secundário , Ensaio de Imunoadsorção Enzimática , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Humanos , Imunoquímica , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/secundário , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Mol Carcinog ; 30(1): 1-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11255259

RESUMO

RET fused gene (RFG)/ELE1alpha/androgen receptor-associated protein 70(ARA70) was first found to be involved in the activation of the RET proto-oncogene in thyroid neoplasm and has recently been shown to be a ligand-dependent transcriptional coregulator for androgen receptor (AR). The functionality of RFG/ELE1alpha/ARA70 remains controversial, and little is known about factors regulating its expression in the prostate. Of significant interest is whether this molecule is involved in prostate carcinogenesis. Using reverse transcriptase-polymerase chain reaction semiquantitation, we compared RFG/ELE1alpha/ARA70 mRNA levels in four prostate cancer cell lines (LNCaP, TSU-Pr1, DU-145, and PC-3) with those found in primary cultures of normal prostatic epithelial cells (PrECs). In addition, we examined the effects of androgen and antiandrogen, estrogen and antiestrogen, and a demethylating agent on RFG/ELE1alpha/ARA70 mRNA expression levels in AR- and AR+ PC-3 cells. Reduced levels of RFG/ELE1alpha/ARA70 message were observed in all four prostate cancer cell lines when compared with normal PrECs in primary cultures. RFG/ELE1alpha/ARA70 mRNA levels in PC-3 cells, which express both estrogen receptor subtypes, were upregulated by 17beta-estradiol and inhibited by the antiestrogen ICI-182780. In PC-3(AR+) cells, which were genetically engineered to express AR, exposure to androgen upregulated RFG/ELE1alpha/ARA70 mRNA expression, whereas treatment with 4-hydroxyflutamide lowered expression of this transcript. Furthermore, treatment of DU-145 cells, which did not express RFG/ELE1alpha/ARA70 transcripts, with a demethylating agent reactivated transcription of this gene. Polymerase chain reaction analyses of monochromosomal human-rodent hybrid panels localized a putative RFG/ELE1alpha/ARA70 isoform on human chromosome 5q31.1-31.2. In summary, we identified sex hormones and DNA hypermethylation as regulators of RFG/ELE1alpha/ARA70 expression in prostate cancer cells. In addition, we found reduced levels of RFG/ELE1alpha/ARA70 expression in prostate cancer cell lines when compared with expression levels in normal PrECs in culture. These findings suggest that RFG/ELE1alpha/ARA70 may be involved prostate carcinogenesis and that it may serve as a key mediator of estrogen-androgen synergism.


Assuntos
Androgênios/fisiologia , Metilação de DNA , Estrogênios/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Próstata/metabolismo , Neoplasias da Próstata/genética , Proteínas Recombinantes de Fusão/genética , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Humanos Par 5 , Primers do DNA , Células Epiteliais/metabolismo , Humanos , Masculino , Próstata/citologia , Neoplasias da Próstata/patologia , Proto-Oncogene Mas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
15.
Mol Carcinog ; 28(4): 236-46, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10972993

RESUMO

Germline mutations of BRCA1 and BRCA2 predispose to hereditary breast, ovarian, and possibly prostate cancer, yet structural mutations in these genes are infrequent in sporadic cancer cases. To better define the involvement of these genes in sporadic cancers, we characterized expression levels of BRCA1 and BRCA2 transcripts in cancer cell lines derived from neoplasms of the ovary, prostate, and breast and compared them with those expressed in primary cultures of normal epithelial cells established from these organs. We observed upregulation of BRCA1 and/or BRCA2 expression in six of seven ovarian cancer cell lines (OVCA420, OVCA429, OVCA432, ALST, DOV13, and SKOV3) when compared with levels found in normal ovary surface epithelial cells. Furthermore, five cancerous or immortalized prostatic epithelial cell lines (BPH-1, TSU-Pr1, LNCaP, PC-3, and DU145) also expressed higher levels of BRCA1 and/or BRCA2 mRNA than did primary cultures of normal prostatic epithelial cells. In contrast, only the estrogen receptor-positive MCF-7 cell line overexpressed these messages, whereas the estrogen receptor-negative breast cancer cell lines Hs578T, MDA-MB-231, and MDA-MB-468 showed no change in expression levels when compared with normal breast epithelial cells. In addition, expanding on our recent identification of a novel BRCA2 transcript variant carrying an in-frame exon 12 deletion (BRCA2 delta 12), we report increased expression of this variant in several ovarian, prostate, and mammary cancer cell lines (OVCA420, OVCA433, ALST, DOV13, SKOV3, TSU-Pr1, DU145, and MDA-MB-468). Most notably, high levels of BRCA2 delta 12 mRNA were detected in an estrogen receptor-positive breast cancer cell line, MCF-7, and in an androgen-independent prostate cancer cell line, DU-145. Interestingly, the wild-type BRCA2 transcript was barely detectable in DU145, which could be used as a model system for future investigations on BRCA2 delta 12 function. Taken together, our data suggest disruption of BRCA1 and/or BRCA2 gene expression in certain epithelial cancer cell lines of the ovary, prostate, and breast. Because wild-type BRCA1 and BRCA2 gene products increase during cell-cycle progression and are believed to exert growth-inhibitory action, enhanced expression of these genes in cancer cells may represent a negative feedback mechanism for curbing proliferation in fast-growing cells. At present, the functionality of BRCA2 delta 12 remains elusive.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Genes BRCA1 , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Neoplasias da Próstata/genética , Fatores de Transcrição/genética , Transcrição Gênica , Proteína BRCA2 , Mama/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Variação Genética , Humanos , Masculino , RNA Mensageiro/genética , Deleção de Sequência , Células Tumorais Cultivadas
16.
J Ethnopharmacol ; 71(3): 483-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10940587

RESUMO

Brandisia hancei is a medicinal herb in China. The ethanol extract of this plant and four phenylethanoid glycosides, acteoside (1), 2'-acetylacteoside (2), poliumoside (3) and brandioside (4), isolated from it were shown to have inhibitory effects on free radical-induced hemolysis of red blood cells and free radical scavenging activities in vitro. Brandioside (4) and poliumoside (3) showed stronger antioxidant effect than acteoside (1), 2'-acetylacteoside (2) and trolox.


Assuntos
Antioxidantes/farmacologia , Flavonoides , Glicosídeos/farmacologia , Medicina Tradicional Chinesa , Fenóis/farmacologia , Plantas Medicinais , Polímeros/farmacologia , Animais , Relação Dose-Resposta a Droga , Hemólise/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis , Ratos
17.
Prostate ; 44(1): 19-25, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10861753

RESUMO

BACKGROUND: Exposure of male Wistar rats to estradiol-17beta (E(2)) in the presence or absence of dihydrotestosterone propionate (DHT) was previously shown to result in prostate inflammation. The present study examines, for the first time, changes in the expression level of several proinflammatory genes during the course of this experimentally induced prostatitis. METHODS: Adult male Wistar rats were given chronic exposure to E(2) + DHT by capsule implantation or were injected with E(2) for short-term exposure. Semiquantitative RT-PCR was employed to measure changes in proinflammatory transcript levels in the separated lobes of the prostate after various times of exposure to estrogen with or without DHT. RESULTS: We observed an upregulation of IL-1beta, IL-6, MIP-2, and inducible nitric oxide synthase (iNOS) after only 4 days treatment with E(2). After 4 weeks of treatment with E(2) + DHT, a significant increase in transcript levels of IL-4, IL-5, IL-6, MIP-2, eotaxin, and iNOS was detected, while IL-1beta and TNF-alpha transcript levels only increased slightly. No increase in transcript levels for cyclooxygenase-2 (cox-2), IFN-gamma, IL-2, or IL-12 was observed. CONCLUSIONS: Upregulation of proinflammatory transcripts occurred shortly after exposure to E(2) and well before any inflammatory cells were observed in the prostate. The pattern of gene expression resembled a T(H)2-type helper-cell response.


Assuntos
Quimiocinas CC , Citocinas/análise , Estradiol/toxicidade , Regulação da Expressão Gênica , Próstata/efeitos dos fármacos , Prostatite/genética , Animais , Quimiocina CCL11 , DNA/química , Primers do DNA/química , Di-Hidrotestosterona/administração & dosagem , Di-Hidrotestosterona/toxicidade , Modelos Animais de Doenças , Estradiol/administração & dosagem , Histocitoquímica , Processamento de Imagem Assistida por Computador , Interleucina-1/análise , Interleucina-4/análise , Interleucina-5/análise , Interleucina-6/análise , Masculino , Óxido Nítrico Sintase/análise , Próstata/patologia , Prostatite/induzido quimicamente , Prostatite/patologia , RNA/química , RNA/isolamento & purificação , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/análise
18.
Cancer Res ; 60(12): 3175-82, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10866308

RESUMO

The aim of the current study is to demonstrate normal and malignant prostatic epithelial cells (PrECs) as targets for receptor-mediated estrogenic and antiestrogenic action. Using an improved protocol, we have successfully isolated and maintained highly enriched populations of normal PrECs from ultrasound-guided peripheral zone biopsies, individually determined to be morphologically normal. Semiquantitative reverse transcription-PCR analyses were used to determine whether transcripts of estrogen receptor (ER)-alpha and those of ER-beta were expressed in our normal PrEC primary cultures, in a commercially available PrEC preparation (PrEC; Clontech), in an immortalized PrEC line established from a benign prostatic hyperplasia specimen (BPH-1), and in three prostatic cancer cell lines (LNCaP, PC-3, and DU145). Expression levels of ER-alpha and ER-beta transcripts were related to those of two estrogen-responsive genes [progesterone receptor (PR) and pS2], at the message levels, to gain insights into the functionality of the ER subtypes in PrECs. Interestingly, only transcripts of ER-beta, but not those of ER-alpha, were found in our primary cultures of normal PrECs, along with both PR and pS2 mRNA. These data strongly suggest that estrogen action was signaled exclusively via ER-beta in normal human PrECs. In contrast, PrEC (Clontech) and BPH-1 cells expressed both ER-alpha and ER-beta transcripts and no PR nor pS2 mRNA in PrEC and only a minimal level of PR mRNA in BPH-1. Among the three prostate cancer cell lines, LNCaP expressed ER-beta mRNA along with transcripts of PR and pS2, DU145 expressed messages of ER-beta and PR, and PC-3 cells exhibited ER-alpha, ER-beta, and pS2 mRNA. Thus, unlike normal PrECs, expression patterns of these genes in malignant PrECs are more variable. Treatment of prostate cancer cells with demethylation agents effectively reactivated the expression of ER-alpha mRNA in LNCaP and DU145 and that of pS2 message in DU145. These findings provide experimental evidence that ER-alpha gene silencing in prostate cancer cells, and perhaps also in normal PrECs, are caused by DNA hypermethylation. To evaluate the potential of using antiestrogens as prostate cancer therapies, we have assessed the growth-inhibitory action of estrogens (estradiol and diethylstilbestrol) and antiestrogens (4-hydroxy-tamoxifen and ICI-182,780) on PC-3 and DU-145 cells. In PC-3 cells, which express both ER subtypes, estrogens as well as antiestrogens are effective inhibitors. In contrast, in DU145 cells, which express only ER-beta, antiestrogens, but not estrogens, are growth inhibitors. By comparison, ICI 182,780 is the more effective cell growth inhibitor. Importantly, the ICI 182,780-induced antiproliferative effects were reversed by cotreatment of DU145 cells with an ER-beta antisense oligonucleotide, hence lending additional support to a central role played by ER-beta in mediating growth-inhibitory action of antiestrogens.


Assuntos
Neoplasias da Próstata/metabolismo , Proteínas , Receptores de Estrogênio/biossíntese , Técnicas de Cultura de Células/métodos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Dietilestilbestrol/farmacologia , Relação Dose-Resposta a Droga , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios não Esteroides/farmacologia , Fulvestranto , Humanos , Masculino , Metilação , Oligonucleotídeos Antissenso/farmacologia , Próstata/metabolismo , Biossíntese de Proteínas , RNA/metabolismo , Receptores Androgênicos/biossíntese , Receptores de Progesterona/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Fator Trefoil-1 , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
19.
Proc Natl Acad Sci U S A ; 96(10): 5722-7, 1999 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-10318951

RESUMO

Our understanding of the roles played by sex hormones in ovarian carcinogenesis has been limited by a lack of data concerning the mode of sex hormone action in human ovarian surface epithelial (HOSE) cells, the tissue of origin of >90% of ovarian cancers. We have compared the relative abundance of estrogen receptor (ER)alpha, ERbeta, progesterone receptor (PR), and androgen receptor (AR) mRNA in four primary cultures of HOSE cells obtained from postmenopausal women to those found in late serous adenocarcinoma primary cell cultures and established ovarian cancer cell lines. We observed coexpression of ERalpha and ERbeta mRNA along with AR and PR transcripts in normal HOSE cells and disruption of ERalpha mRNA expression as well as dramatic down-regulation of PR and AR transcript expression in most ovarian cancer cells. In contrast, levels of ERbeta mRNA were unaffected by the malignant state. Additionally, a novel mutation involving a 32-bp deletion in exon 1 of ERalpha transcripts was detected in the SKOV3 cell line. This mutation would explain why SKOV3 was reported to be ER-positive but estrogen-insensitive. Taken together, these findings suggest that estrogens, signaling via either or both ER subtypes, may play an indispensable role in regulating normal HOSE cell functions. Therefore, loss of ERalpha, PR, and AR mRNA expression in HOSE cells may be responsible for neoplastic transformation in this cell type. In contrast, the roles played by ERbeta in normal and malignant HOSE cells remain elusive. Finally, the coexistence of mutated ERalpha mRNA and normal ERbeta transcripts in SKOV3 argues in favor of a dependency of ERbeta action on functional ERalphas.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Células Epiteliais/metabolismo , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Éxons , Feminino , Humanos , Mutação , Neoplasias Ovarianas/genética , Pós-Menopausa , RNA Mensageiro/metabolismo , Receptores Androgênicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Deleção de Sequência , Células Tumorais Cultivadas
20.
Toxicol Appl Pharmacol ; 154(1): 20-7, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9882588

RESUMO

Highly sensitive, sequence-specific competitive reverse transcriptase-polymerase chain reaction (RT-PCR) protocols were established for the detection and quantification of metallothionein (MT)-I and MT-II messages, in absolute values, in rat tissues. Detection limits for these protocols were in the range of 5 to 10 amol per microgram total RNA. Levels of MT-I and MT-II transcripts in the three major prostatic lobes, kidney, and testis were measured in untreated and cadmium (Cd)-treated rats. The dorsal prostate (DP), lateral prostate (LP), kidney, and testis expressed substantial levels of MT-I and MT-II mRNA while the ventral prostate (VP) had extremely low levels of the transcripts. Cd treatment induced higher levels of MT-I and/or MT-II mRNA expression in all tissues studied with the exception of LP. In the LP, Cd treatment caused reductions of MT-I and MT-II mRNA levels. The Cd-induced levels attained in the VP following Cd exposure were still markedly lower than those found in the kidney, testis, LP, and DP of untreated animals. These findings contradict previous claims that the MT genes in rat VP are unresponsive to Cd activation. The susceptibility of VP to Cd toxicity/carcinogenicity may therefore be explained by low levels of Cd-induced expression rather than lack of induction of MTs.


Assuntos
Cádmio/farmacologia , Expressão Gênica/efeitos dos fármacos , Metalotioneína/genética , Próstata/metabolismo , RNA Mensageiro/análise , Animais , Ligação Competitiva , Cádmio/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Próstata/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testículo/efeitos dos fármacos , Testículo/metabolismo
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