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1.
J Pathol ; 231(1): 77-87, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23729330

RESUMO

Levels of caveolin-1 (Cav-1) in tumour epithelial cells increase during prostate cancer progression. Conversely, Cav-1 expression in the stroma can decline in advanced and metastatic prostate cancer. In a large cohort of 724 prostate cancers, we observed significantly decreased levels of stromal Cav-1 in concordance with increased Gleason score (p = 0.012). Importantly, reduced expression of Cav-1 in the stroma correlated with reduced relapse-free survival (p = 0.009), suggesting a role for stromal Cav-1 in inhibiting advanced disease. Silencing of Cav-1 by shRNA in WPMY-1 prostate fibroblasts resulted in up-regulation of Akt phosphorylation, and significantly altered expression of genes involved in angiogenesis, invasion, and metastasis, including a > 2.5-fold increase in TGF-ß1 and γ-synuclein (SNCG) gene expression. Moreover, silencing of Cav-1 induced migration of prostate cancer cells when stromal cells were used as attractants. Pharmacological inhibition of Akt caused down-regulation of TGF-ß1 and SNCG, suggesting that loss of Cav-1 in the stroma can influence Akt-mediated signalling in the tumour microenvironment. Cav-1-depleted stromal cells exhibited increased levels of intracellular cholesterol, a precursor for androgen biosynthesis, steroidogenic enzymes, and testosterone. These findings suggest that loss of Cav-1 in the tumour microenvironment contributes to the metastatic behaviour of tumour cells by a mechanism that involves up-regulation of TGF-ß1 and SNCG through Akt activation. They also suggest that intracrine production of androgens, a process relevant to castration resistance, may occur in the stroma.


Assuntos
Adenocarcinoma/mortalidade , Caveolina 1/metabolismo , Neoplasias da Próstata/mortalidade , Células Estromais/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Biomarcadores/metabolismo , Progressão da Doença , Intervalo Livre de Doença , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Masculino , Recidiva Local de Neoplasia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Taxa de Sobrevida , Transfecção , Fator de Crescimento Transformador beta1/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral , gama-Sinucleína/metabolismo
2.
Int J Cardiol ; 412: 132336, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964548

RESUMO

BACKGROUND: Takotsubo syndrome (TS) is a reversible cause of heart failure; however, a minority of patients can develop serious complications, including cardiac rupture (CR). OBJECTIVES: Analyze case reports of CR related to TS, detailing patient characteristics to uncover risk factors and prognosis for this severe complication. METHODS: We conducted a systematic search of MEDLINE and Embase databases to identify case reports of patients with TS complicated by CR, from inception to October 2023. RESULTS: We included 44 subjects (40 females; 4 males) with a median age of 75 (IQR 71-82) years, of White/Caucasian (61%) or East Asian/Japanese (39%) ethnicity. An emotional trigger was present in 15 (34%) subjects and an apical ballooning pattern was observed in all cases (100%). ST-segment elevation was reported in 39 (93%) of 42 cases, with the anterior myocardial segments (37 [88%]) being the most compromised, followed by lateral (26 [62%]) and inferior (14 [33%]) segments. The median time to cardiac rupture was 48 (5-120) hours since admission, with the left ventricular free wall (25 [57%]) being the most frequent site of perforation. Surgery was attempted in 16 (36%) cases, and 28 (64%) patients did not survive. CONCLUSIONS: CR related to TS is a rare complication associated with high mortality and affecting elderly females, specially from White/Caucasian or East Asian/Japanese descent, presenting with anterior or lateral ST-segment elevation, and an apical ballooning pattern. Although data is limited and additional prospective studies are needed, the awareness of this life-threatening complication is crucial to early identify high-risk patients. CONDENSED ABSTRACT: Cardiac rupture is a rare complication of Takotsubo syndrome. We conducted a systematic review of cases complicated by cardiac rupture, and we identified 44 subjects (40 females and 4 males) with a median age of 75 (IQR 71-82) years, of White/Caucasian (61%) or East Asian/Japanese (39%) ethnicity, all with an apical ballooning pattern (100%). The median time to cardiac rupture was 48 (5-120) hours since admission, with the left ventricular free wall (25 [57%]) being the most frequent site of perforation. Surgery treatment was attempted in 16 (36%) cases, and 28 (64%) patients did not survive.

3.
Int J Cardiol ; 395: 131394, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37748523

RESUMO

BACKGROUND: Myocardial injury is associated with adverse outcomes. No data are reported about sex differences in incidence and factors associated with myocardial injury in an emergency department (ED) setting from a real-world perspective. We aimed to assess whether sex plays a major role in the diagnosis of myocardial injury in the ED. METHODS: In this subanalysis of a retrospective study, patients presenting at the ED with at least one high-sensitivity cardiac troponin T (hs-cTnT) value and without acute coronary syndromes diagnosis were compared. RESULTS: 31,383 patients were admitted to the ED, 4660 had one hs-cTnT value, and 3937 were enrolled: 1943 females (49.4%) and 1994 males (50.6%). The diagnosis of myocardial injury was higher among men (36.8% vs. 32.9%, p < 0.01). Male sex was independently associated with myocardial injury. An older age, an elevated NT-proB-type Natriuretic Peptide and a lower estimated glomerular filtrate rate were independently associated with myocardial injury in both sexes. CONCLUSIONS: In the ED, from a real-world perspective, myocardial injury occurred more frequently in males, and it was associated with older age and the presence of cardiac, lung, and kidney disease but not higher hs-cTnT values.


Assuntos
Síndrome Coronariana Aguda , Traumatismos Cardíacos , Humanos , Masculino , Feminino , Estudos Retrospectivos , Caracteres Sexuais , Biomarcadores , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/epidemiologia , Serviço Hospitalar de Emergência , Troponina T
4.
Am J Pathol ; 181(5): 1573-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23022210

RESUMO

Oncosomes are tumor-derived microvesicles that transmit signaling complexes between cell and tissue compartments. Herein, we show that amoeboid tumor cells export large (1- to 10-µm diameter) vesicles, derived from bulky cellular protrusions, that contain metalloproteinases, RNA, caveolin-1, and the GTPase ADP-ribosylation factor 6, and are biologically active toward tumor cells, endothelial cells, and fibroblasts. We describe methods by which large oncosomes can be selectively sorted by flow cytometry and analyzed independently of vesicles <1 µm. Structures resembling large oncosomes were identified in the circulation of different mouse models of prostate cancer, and their abundance correlated with tumor progression. Similar large vesicles were also identified in human tumor tissues, but they were not detected in the benign compartment. They were more abundant in metastases. Our results suggest that tumor microvesicles substantially larger than exosome-sized particles can be visualized and quantified in tissues and in the circulation, and isolated and characterized using clinically adaptable methods. These findings also suggest a mechanism by which migrating tumor cells condition the tumor microenvironment and distant sites, thereby potentiating advanced disease.


Assuntos
Micropartículas Derivadas de Células/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Fator 6 de Ribosilação do ADP , Animais , Caveolina 1/metabolismo , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/ultraestrutura , Citometria de Fluxo , Humanos , Masculino , Camundongos , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/ultraestrutura
5.
J Clin Med ; 11(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35807089

RESUMO

Background. Nowadays, it is still not possible to clinically distinguish whether an increase in high-sensitivity cardiac troponin (hs-cTn) values is due to myocardial injury or an acute coronary syndrome (ACS). Moreover, predictive data regarding hs-cTnT in an emergency room (ER) setting are scarce. This monocentric retrospective study aimed to improve the knowledge and interpretation of this cardiac biomarker in daily clinical practice. Methods. Consecutive adult patients presenting at the ER and hospitalized with a first abnormal hs-cTnT value (≥14 ng/L) were enrolled for 6 months. The baseline hs-cTnT value and the ensuing changes and variations were correlated with the clinical presentation and the type of diagnosis. Subsequently, multivariable models were built to assess which clinical/laboratory variables most influenced hospital admissions in the investigated population analyzed according to the final reason for hospitalization: (1) cardiovascular vs. non-cardiovascular diagnosis, and (2) ACS vs. non-ACS one. Results. A total of 4660 patients were considered, and, after a first screening, 4149 patients were enrolled. Out of 4129 patients, 1555 (37.5%) had a first hs-cTnT ≥14 ng/L, and 1007 (65%) were hospitalized with the following types of diagnosis: ACS (182; 18%), non-ACS cardiovascular disease (337; 34%) and non-cardiovascular disease (487; 48%). Higher hs-cTnT values and significant hs-cTnT variations were found in the ACS group (p < 0.01). The mean percentage of variation was higher in patients with ACS, intermediate in those with non-ACS cardiovascular disease, and low in those with non-cardiovascular disease (407.5%, 270.6% and 12.4%, respectively). Only syncope and CRP (OR: 0.08, 95% CI: 0.02−0.39, p < 0.01 and OR: 0.9988, 95% CI: 0.9979−0.9998, p = 0.02, respectively) or CRP (OR: 0.9948, 95% CI: 0.9908−0.9989, p = 0.01) and NT-proBNP (OR: 1.0002, 95% CI: 1.0000−1.0004, p = 0.02) were independent predictors of a cardiovascular disease diagnosis. On the other hand, only chest pain (OR: 22.91, 95% CI: 3.97−132.32, p < 0.01) and eGFR (OR: 1.04, 95% CI: 1.004−1.083, p = 0.03) were associated with the ACS diagnosis. Conclusions. Differently from the investigated biomarkers, in this study, only clinical variables predicted hospitalizations in different patients' subgroups.

6.
Transl Oncol ; 14(3): 101013, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33516089

RESUMO

Copy Number Alterations (CNAs) represent the most common genetic alterations identified in ovarian cancer cells, being responsible for the extensive genomic instability observed in this cancer. Here we report the identification of CNAs in a cohort of Italian patients affected by ovarian cancer performed by SNP-based array. Our analysis allowed the identification of 201 significantly altered chromosomal bands (70 copy number gains; 131 copy number losses). The 3300 genes subjected to CNA identified here were compared to those present in the TCGA dataset. The analysis allowed the identification of 11 genes with increased CN and mRNA expression (PDCD10, EBAG9, NUDCD1, ENY2, CSNK2A1, TBC1D20, ZCCHC3, STARD3, C19orf12, POP4, UQCRFS1). PDCD10 was selected for further studies because of the highest frequency of CNA. PDCD10 was found, by immunostaining of three different Tissue Micro Arrays, to be over-expressed in the majority of ovarian primary cancer samples and in metastatic lesions. Moreover, significant correlations were found in specific subsets of patients, between increased PDCD10 expression and grade (p < 0.005), nodal involvement (p < 0.05) or advanced FIGO stage (p < 0.01). Finally, manipulation of PDCD10 expression by shRNA in ovarian cancer cells (OVCAR-5 and OVCA429) demonstrated a positive role for PDCD10 in the control of cell growth and motility in vitro and tumorigenicity in vivo. In conclusion, this study allowed the identification of novel genes subjected to copy number alterations in ovarian cancer. In particular, the results reported here point to a prominent role of PDCD10 as a bona fide oncogene.

7.
J Extracell Vesicles ; 9(1): 1689784, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31839905

RESUMO

Tumour cells release diverse populations of extracellular vesicles (EVs) ranging in size, molecular cargo, and function. We sought to characterize mRNA and protein content of EV subpopulations released by human glioblastoma (GBM) cells expressing a mutant form of epidermal growth factor receptor (U87EGFRvIII) in vitro and in vivo with respect to size, morphology and the presence of tumour cargo. The two EV subpopulations purified from GBM U87EGFRvIII cancer cells, non-cancer human umbilical vein endothelial cells (HUVEC; control) and serum of U87EGFRvIII glioma-bearing mice using differential centrifugation (EVs that sediment at 10,000 × g or 100,000 × g are termed large EVs and small EVs, respectively) were characterized using transmission electron microscopy (TEM), confocal microscopy, nanoparticle tracking analysis (NTA), flow cytometry, immunofluorescence (IF), quantitative-polymerase chain reaction (qPCR), droplet digital polymerase chain reaction (ddPCR) and micro-nuclear magnetic resonance (µNMR). We report that both U87EGFRvIII and HUVEC release a similar number of small EVs, but U87EGFRvIII glioma cells alone release a higher number of large EVs compared to non-cancer HUVEC. The EGFRvIII mRNA from the two EV subpopulations from U87EGFRvIII glioma cells was comparable, while the EGFR protein (wild type + vIII) levels are significantly higher in large EVs. Similarly, EGFRvIII mRNA in large and small EVs isolated from the serum of U87EGFRvIII glioma-bearing mice is comparable, while the EGFR protein (wild type + vIII) levels are significantly higher in large EVs. Here we report for the first time a direct comparison of large and small EVs released by glioma U87EGFRvIII cells and from serum of U87EGFRvIII glioma-bearing mice. Both large and small EVs contain tumour-specific EGFRvIII mRNA and proteins and combining these platforms may be beneficial in detecting rare mutant events in circulating biofluids.

8.
Endocrinology ; 149(9): 4256-66, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18499757

RESUMO

Estrogen exerts neuroprotective effects and reduces beta-amyloid accumulation in models of Alzheimer's disease (AD). A few years ago, a new neuroprotective gene, i.e. seladin-1 (for selective AD indicator-1), was identified and found to be down-regulated in AD vulnerable brain regions. Seladin-1 inhibits the activation of caspase-3, a key modulator of apoptosis. In addition, it has been demonstrated that the seladin-1 gene encodes 3beta-hydroxysterol Delta24-reductase, which catalyzes the synthesis of cholesterol from desmosterol. We have demonstrated previously that in fetal neuroepithelial cells, 17beta-estradiol (17betaE2), raloxifene, and tamoxifen exert neuroprotective effects and increase the expression of seladin-1. The aim of the present study was to elucidate whether seladin-1 is directly involved in estrogen-mediated neuroprotection. Using the small interfering RNA methodology, significantly reduced levels of seladin-1 mRNA and protein were obtained in fetal neuroepithelial cells. Seladin-1 silencing determined the loss of the protective effect of 17betaE2 against beta-amyloid and oxidative stress toxicity and caspase-3 activation. A computer-assisted analysis revealed the presence of half-palindromic estrogen responsive elements upstream from the coding region of the seladin-1 gene. A 1490-bp region was cloned in a luciferase reporter vector, which was transiently cotransfected with the estrogen receptor alpha in Chinese hamster ovarian cells. The exposure to 17betaE2, raloxifene, tamoxifen, and the soy isoflavones genistein and zearalenone increased luciferase activity, thus suggesting a functional role for the half-estrogen responsive elements of the seladin-1 gene. Our data provide for the first time a direct demonstration that seladin-1 may be considered a fundamental mediator of the neuroprotective effects of estrogen.


Assuntos
Citoproteção/efeitos dos fármacos , Estradiol/farmacologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/efeitos dos fármacos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/fisiologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Sequência de Bases , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Cricetinae , Cricetulus , Citoproteção/genética , Inativação Gênica/fisiologia , Humanos , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , RNA Interferente Pequeno/farmacologia , Fatores de Tempo
9.
Oncotarget ; 6(42): 44072-83, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26624980

RESUMO

FYN is a SRC family kinase (SFK) that has been shown to be up-regulated in human prostate cancer (PCa) tissues and cell lines. In this study, we observed that FYN is strongly up-regulated in human neuroendocrine PCa (NEPC) tissues and xenografts, as well as cells derived from a NEPC transgenic mouse model. In silico analysis of FYN expression in prostate cancer cell line databases revealed an association with the expression of neuroendocrine (NE) markers such as CHGA, CD44, CD56, and SYP. The loss of FYN abrogated the invasion of PC3 and ARCaPM cells in response to MET receptor ligand HGF. FYN also contributed to the metastatic potential of NEPC cells in two mouse models of visceral metastasis with two different cell lines (PC3 and TRAMPC2-RANKL). The activation of MET appeared to regulate neuroendocrine (NE) features as evidenced by increased expression of NE markers in PC3 cells with HGF. Importantly, the overexpression of FYN protein in DU145 cells was directly correlated with the increase of CHGA. Thus, our data demonstrated that the neuroendocrine differentiation that occurs in PCa cells is, at least in part, regulated by FYN kinase. Understanding the role of FYN in the regulation of NE markers will provide further support for ongoing clinical trials of SFK and MET inhibitors in castration-resistant PCa patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Movimento Celular , Neoplasias Hepáticas/enzimologia , Tumores Neuroendócrinos/enzimologia , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Animais , Biomarcadores Tumorais/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células , Cromogranina A/metabolismo , Simulação por Computador , Bases de Dados Genéticas , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Masculino , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Invasividade Neoplásica , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/secundário , Fenótipo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-fyn/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Carga Tumoral , Regulação para Cima
10.
Oncotarget ; 6(13): 11327-41, 2015 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-25857301

RESUMO

Large oncosomes (LO) are atypically large (1-10 µm diameter) cancer-derived extracellular vesicles (EVs), originating from the shedding of membrane blebs and associated with advanced disease. We report that 25% of the proteins, identified by a quantitative proteomics analysis, are differentially represented in large and nano-sized EVs from prostate cancer cells. Proteins enriched in large EVs included enzymes involved in glucose, glutamine and amino acid metabolism, all metabolic processes relevant to cancer. Glutamine metabolism was altered in cancer cells exposed to large EVs, an effect that was not observed upon treatment with exosomes. Large EVs exhibited discrete buoyant densities in iodixanol (OptiPrep(TM)) gradients. Fluorescent microscopy of large EVs revealed an appearance consistent with LO morphology, indicating that these structures can be categorized as LO. Among the proteins enriched in LO, cytokeratin 18 (CK18) was one of the most abundant (within the top 5th percentile) and was used to develop an assay to detect LO in the circulation and tissues of mice and patients with prostate cancer. These observations indicate that LO represent a discrete EV type that may play a distinct role in tumor progression and that may be a source of cancer-specific markers.


Assuntos
Biomarcadores Tumorais/metabolismo , Micropartículas Derivadas de Células/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/patologia , Centrifugação , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Forminas , Glutamina/metabolismo , Humanos , Queratina-18/metabolismo , Masculino , Camundongos , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/genética , Tamanho das Organelas , Neoplasias da Próstata/sangue , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transporte Proteico , Proteômica/métodos , Interferência de RNA , Espectrometria de Massas em Tandem , Transfecção
11.
Cell Cycle ; 12(22): 3526-36, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24091630

RESUMO

Prostate cancer cells release atypically large extracellular vesicles (EVs), termed large oncosomes, which may play a role in the tumor microenvironment by transporting bioactive molecules across tissue spaces and through the blood stream. In this study, we applied a novel method for selective isolation of large oncosomes applicable to human platelet-poor plasma, where the presence of caveolin-1-positive large oncosomes identified patients with metastatic disease. This procedure was also used to validate results of a miRNA array performed on heterogeneous populations of EVs isolated from tumorigenic RWPE-2 prostate cells and from isogenic non-tumorigenic RWPE-1 cells. The results showed that distinct classes of miRNAs are expressed at higher levels in EVs derived from the tumorigenic cells in comparison to their non-tumorigenic counterpart. Large oncosomes enhanced migration of cancer-associated fibroblasts (CAFs), an effect that was increased by miR-1227, a miRNA abundant in large oncosomes produced by RWPE-2 cells. Our findings suggest that large oncosomes in the circulation report metastatic disease in patients with prostate cancer, and that this class of EV harbors functional molecules that may play a role in conditioning the tumor microenvironment.


Assuntos
Caveolina 1/metabolismo , Micropartículas Derivadas de Células/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Linhagem Celular Tumoral , Movimento Celular , Fibroblastos/patologia , Fibroblastos/fisiologia , Redes Reguladoras de Genes , Humanos , Técnicas In Vitro , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Transporte de RNA , Microambiente Tumoral
12.
EMBO Mol Med ; 4(8): 743-60, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22593025

RESUMO

Therapies for most malignancies are generally ineffective once metastasis occurs. While tumour cells migrate through tissues using diverse strategies, the signalling networks controlling such behaviours in human tumours are poorly understood. Here we define a role for the Diaphanous-related formin-3 (DIAPH3) as a non-canonical regulator of metastasis that restrains conversion to amoeboid cell behaviour in multiple cancer types. The DIAPH3 locus is close to RB1, within a narrow consensus region of deletion on chromosome 13q in prostate, breast and hepatocellular carcinomas. DIAPH3 silencing in human carcinoma cells destabilized microtubules and induced defective endocytic trafficking, endosomal accumulation of EGFR, and hyperactivation of EGFR/MEK/ERK signalling. Silencing also evoked amoeboid properties, increased invasion and promoted metastasis in mice. In human tumours, DIAPH3 down-regulation was associated with aggressive or metastatic disease. DIAPH3-silenced cells were sensitive to MEK inhibition, but showed reduced sensitivity to EGFR inhibition. These findings have implications for understanding mechanisms of metastasis, and suggest that identifying patients with chromosomal deletions at DIAPH3 may have prognostic value.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Metástase Neoplásica/patologia , Neoplasias/patologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Forminas , Inativação Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C
13.
J Steroid Biochem Mol Biol ; 124(3-5): 77-83, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21296663

RESUMO

Neurosteroids are involved in Central Nervous System development, brain functionality and neuroprotection but little is known about regulators of their biosynthesis. Recently gonadotropins, Gonadotropin-releasing Hormone (GnRH) and their receptors have been localized in different brain regions, such as hippocampus and cortex. Using human neuronal-like cells we found that GnRH up-regulates the expression of key genes of cholesterol and steroid synthesis when used in a narrow range around 1.0 nM. The expression of Hydroxysterol D24-reductase (seladin-1/DHCR24), that catalyzes the last step of cholesterol biosynthesis, is increased by 50% after 90 min of incubation with GnRH. StAR protein and P450 side chain cleavage (P450scc) are up-regulated by 3.3 times after 90 min and by 3.5 times after 3 h, respectively. GnRH action is mediated by LH and 1.0 nM GnRH enhances the expression of LHß as well. A two fold increase of cell cholesterol is induced after 90 min of GnRH incubation and 17ß-estradiol (E2) production is increased after 24, 48 and 72 h. These data indicate for the first time that GnRH regulates both cholesterol and steroid biosynthesis in human neuronal-like cells and suggest a new physiological role for GnRH in the brain.


Assuntos
Colesterol/biossíntese , Hormônio Liberador de Gonadotropina/farmacologia , Neurônios/efeitos dos fármacos , Esteroides/biossíntese , Encéfalo/citologia , Encéfalo/metabolismo , Linhagem Celular , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Hormônio Luteinizante Subunidade beta/genética , Hormônio Luteinizante Subunidade beta/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo
14.
Cell Cycle ; 8(15): 2420-4, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19556867

RESUMO

Here, we examined the status of stromal Cav-1 expression in patients with benign prostatic hypertrophy (BPH), primary prostate cancers (PCa), and prostate-cancer metastases (Mets). Interestingly, an absence of stromal Cav-1 directly correlated with prostate cancer disease progression. For example, virtually all BPH samples showed abundant stromal Cav-1 immunostaining. In contrast, in a subset of patients with primary prostate cancer, the stromal levels of Cav-1 were significantly decreased, and this correlated with a high Gleason score, indicative of a worse prognosis and poor clinical outcome. Remarkably, all metastatic tumors (either from lymph node or bone) were completely negative for stromal Cav-1 staining. Thus, stromal Cav-1 expression may be considered as a new biomarker of prostate cancer disease progression and metastasis. Mechanistically, stromal Cav-1 levels were inversely correlated with the epithelial expression levels of Cav-1 and epithelial phospho-Akt. Thus, loss of stromal Cav-1 is predictive of elevated levels of epithelial Cav-1 and epithelial Akt-activation. This provides important new clinical evidence for paracrine signaling between prostate cancer epithelial cells and the tumor stromal micro-environment, especially related to disease progression and metastasis.


Assuntos
Caveolina 1/metabolismo , Neoplasias/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Progressão da Doença , Epitélio/metabolismo , Humanos , Masculino , Metástase Neoplásica/patologia , Neoplasias/patologia , Neoplasias da Próstata/metabolismo , Células Estromais/metabolismo , Análise Serial de Tecidos
15.
Cancer Res ; 69(13): 5601-9, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19549916

RESUMO

Oncosomes have recently been described as membrane-derived microvesicles secreted by cancer cells, which transfer oncogenic signals and protein complexes across cell boundaries. Here, we show the rapid formation and secretion of oncosomes from DU145 and LNCaP human prostate cancer cells. Oncosome formation was stimulated by epidermal growth factor receptor activation and also by overexpression of membrane-targeted Akt1. Microvesicles shed from prostate cancer cells contained numerous signal transduction proteins and were capable of activating rapid phospho-tyrosine and Akt pathway signaling, and stimulating proliferation and migration, in recipient tumor cells. They also induced a stromal reaction in recipient normal cells. Knockdown of the actin nucleating protein Diaphanous Related Formin 3 (DRF3/Dia2) by RNA interference enhanced rates of oncosome formation, indicating that these structures resemble, and may be identical to, nonapoptotic membrane blebs, a feature of the amoeboid form of cell motility. Analysis of primary and metastatic human prostate tumors using 100K single nucleotide polymorphism arrays revealed a significantly higher frequency of deletion of the locus encoding DRF3 (DIAPH3) in metastatic tumors (P = 0.001) in comparison with organ-confined tumors. Fluorescence in situ hybridization confirmed increased chromosomal loss of DIAPH3 in metastatic tumors in a different cohort of patients (P = 0.006). These data suggest that microvesicles shed from prostate cancer cells can alter the tumor microenvironment in a manner that may promote disease progression. They also show that DRF3 is a physiologically relevant protein that seems to regulate this process.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 13 , Metástase Neoplásica/genética , Neoplasias da Próstata/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Vesícula/patologia , Divisão Celular , Linhagem Celular Tumoral , Primers do DNA , Forminas , Humanos , Hibridização in Situ Fluorescente , Masculino , Proteínas de Neoplasias/metabolismo , Oncogenes/genética , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/patologia , Interferência de RNA , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transfecção
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