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The development of castration-resistant prostate cancer (CRPC) is driven by intricate genetic and epigenetic mechanisms. Traf2- and Nck-interacting kinase (TNIK) has been reported as a serine/threonine kinase associated with tumor cell proliferation or unfavorable cancer behavior. The microarray approach revealed a substantial upregulation of TNIK expression levels, enabling us to investigate the functional behaviors of the TNIK gene in CRPC. Specifically, we discovered that AR suppresses TNIK gene transcription in LNCaP and C4-2 cells by forming a complex with H3K27me3. Following the reduction of AR levels induced by androgen deprivation therapy (ADT), TNIK is recruited to activate EGFR signaling through phosphorylation in C4-2 cells, thereby promoting CRPC progression. Our findings unveil a regulatory role of AR as a repressor for TNIK while also highlighting how TNIK activates the EGFR pathway via phosphorylation to drive CRPC progression. Consequently, targeting TNIK may represent an appealing therapeutic strategy for CRPC.
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The receptor Triggering Receptor Expressed on Myeloid cells 2 (TREM2) is associated with several neurodegenerative diseases including Alzheimer's Disease and TREM2 stimulation represents a novel therapeutic opportunity. TREM2 can be activated by antibodies targeting the stalk region, most likely through receptor dimerization. Endogenous ligands of TREM2 are suggested to be negatively charged apoptotic bodies, mimicked by phosphatidylserine incorporated in liposomes and other polyanionic molecules likely binding to TREM2 IgV fold. However, there has been much discrepancy in the literature on the nature of phospholipids (PLs) that can activate TREM2 and on the stability of the corresponding liposomes over time. We describe optimized liposomes as robust agonists selective for TREM2 over TREM1 in cellular system. The detailed structure/activity relationship studies of lipid polar heads indicate that negatively charged lipid heads are required for activity and we identified the shortest maximally active PL sidechain. Optimized liposomes are active on both TREM2 common variant and TREM2 R47H mutant. Activity and selectivity were further confirmed in different native TREM2 expressing cell types including on integrated cellular responses such as stimulation of phagocytic activity. Such tool agonists will be useful in further studies of TREM2 biology in cellular systems alongside antibodies, and in the design of small molecule synthetic TREM2 agonists.
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Enfermedad de Alzheimer , Liposomas , Glicoproteínas de Membrana/inmunología , Receptores Inmunológicos/inmunología , Enfermedad de Alzheimer/metabolismo , Anticuerpos/metabolismo , Encéfalo/metabolismo , Humanos , Ligandos , Microglía/metabolismo , Células Mieloides/metabolismo , Fosfatidilserinas/metabolismo , Receptor Activador Expresado en Células Mieloides 1/metabolismoRESUMEN
BACKGROUND: Prostate cancer (PC) can display very heterogeneous phenotypes ranging from indolent asymptomatic to aggressive lethal forms. Understanding how these PC subtypes vary in their striving for energy and anabolic molecules is of fundamental importance for developing more effective therapies and diagnostics. Here, we carried out an extensive analysis of prostate tissue samples to reveal metabolic alterations during PC development and disease progression and furthermore between TMPRSS2-ERG rearrangement-positive and -negative PC subclasses. METHODS: Comprehensive metabolomics analysis of prostate tissue samples was performed by non-destructive high-resolution magic angle spinning nuclear magnetic resonance (1H HR MAS NMR). Subsequently, samples underwent moderate extraction, leaving tissue morphology intact for histopathological characterization. Metabolites in tissue extracts were identified by 1H/31P NMR and liquid chromatography-mass spectrometry (LC-MS). These metabolomics profiles were analyzed by chemometric tools and the outcome was further validated using proteomic data from a separate sample cohort. RESULTS: The obtained metabolite patterns significantly differed between PC and benign tissue and between samples with high and low Gleason score (GS). Five key metabolites (phosphocholine, glutamate, hypoxanthine, arginine and α-glucose) were identified, who were sufficient to differentiate between cancer and benign tissue and between high to low GS. In ERG-positive PC, the analysis revealed several acylcarnitines among the increased metabolites together with decreased levels of proteins involved in ß-oxidation; indicating decreased acyl-CoAs oxidation in ERG-positive tumors. The ERG-positive group also showed increased levels of metabolites and proteins involved in purine catabolism; a potential sign of increased DNA damage and oxidative stress. CONCLUSIONS: Our comprehensive metabolomic analysis strongly indicates that ERG-positive PC and ERG-negative PC should be considered as different subtypes of PC; a fact requiring different, sub-type specific treatment strategies for affected patients.
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Biomarcadores de Tumor/análisis , Metaboloma , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/patología , Estudios de Seguimiento , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Clasificación del Tumor , Prostatectomía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/cirugíaRESUMEN
Bone metastasis is the lethal end-stage of prostate cancer (PC), but the biology of bone metastases is poorly understood. The overall aim of this study was therefore to explore molecular variability in PC bone metastases of potential importance for therapy. Specifically, genome-wide expression profiles of bone metastases from untreated patients (n = 12) and patients treated with androgen-deprivation therapy (ADT, n = 60) were analyzed in relation to patient outcome and to morphological characteristics in metastases and paired primary tumors. Principal component analysis and unsupervised classification were used to identify sample clusters based on mRNA profiles. Clusters were characterized by gene set enrichment analysis and related to histological and clinical parameters using univariate and multivariate statistics. Selected proteins were analyzed by immunohistochemistry in metastases and matched primary tumors (n = 52) and in transurethral resected prostate (TUR-P) tissue of a separate cohort (n = 59). Three molecular subtypes of bone metastases (MetA-C) characterized by differences in gene expression pattern, morphology, and clinical behavior were identified. MetA (71% of the cases) showed increased expression of androgen receptor-regulated genes, including prostate-specific antigen (PSA), and glandular structures indicating a luminal cell phenotype. MetB (17%) showed expression profiles related to cell cycle activity and DNA damage, and a pronounced cellular atypia. MetC (12%) exhibited enriched stroma-epithelial cell interactions. MetB patients had the lowest serum PSA levels and the poorest prognosis after ADT. Combined analysis of PSA and Ki67 immunoreactivity (proliferation) in bone metastases, paired primary tumors, and TUR-P samples was able to differentiate MetA-like (high PSA, low Ki67) from MetB-like (low PSA, high Ki67) tumors and demonstrate their different prognosis. In conclusion, bone metastases from PC patients are separated based on gene expression profiles into molecular subtypes with different morphology, biology, and clinical outcome. These findings deserve further exploration with the purpose of improving treatment of metastatic PC.
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Neoplasias Óseas/clasificación , Neoplasias Óseas/genética , Perfilación de la Expresión Génica , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Antígeno Ki-67/metabolismo , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Pronóstico , Antígeno Prostático Específico/metabolismo , Resultado del TratamientoRESUMEN
A correction to this paper has been published and can be accessed via a link at the top of the paper.
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Based on gene-expression profiles, prostate tumors can be subdivided into subtypes with different aggressiveness and response to treatment. We investigated if similar clinically relevant subgroups can be identified simply by the combination of two immunohistochemistry markers: one for tumor cell differentiation (prostate specific antigen, PSA) and one for proliferation (Ki67). This was analyzed in men with prostate cancer diagnosed at transurethral resection of the prostate 1975-1991 (n = 331) where the majority was managed by watchful waiting. Ki67 and PSA immunoreactivity was related to outcome and to tumor characteristics previously associated with prognosis. Increased Ki67 and decreased PSA were associated with poor outcome, and they provided independent prognostic information from Gleason score. A combinatory score for PSA and Ki67 immunoreactivity was produced using the median PSA and Ki67 levels as cut-off (for Ki67 the upper quartile was also evaluated) for differentiation into subgroups. Patients with PSA low/Ki67 high tumors showed higher Gleason score, more advanced tumor stage, and higher risk of prostate cancer death compared to other patients. Their tumor epithelial cells were often ERG positive and expressed higher levels of ErbB2, phosphorylated epidermal growth factor receptor (pEGF-R) and protein kinase B (pAkt), and their tumor stroma showed a reactive response with type 2 macrophage infiltration, high density of blood vessels and hyaluronic acid, and with reduced levels of caveolin-1, androgen receptors, and mast cells. In contrast, men with PSA high/Ki67 low tumors were characterized by low Gleason score, and the most favorable outcome amongst PSA/Ki67-defined subgroups. Men with PSA low/Ki67 low tumors showed clinical and tumor characteristics intermediate of the two groups above. A combinatory PSA/Ki67 immunoreactivity score identifies subgroups of prostate cancers with different epithelial and stroma phenotypes and highly different outcome but the clinical usefulness of this approach needs to be validated in other cohorts.
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Biomarcadores de Tumor/análisis , Calicreínas/análisis , Antígeno Ki-67/análisis , Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/patología , Anciano , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/mortalidadRESUMEN
Castration-resistant prostate cancer (CRPC) with neuroendocrine differentiation (NED) is a lethal disease for which effective therapies are urgently needed. The mechanism underlying development of CRPC with NED, however, remains largely uncharacterized. In this study, we explored and characterized the functional role of neurotensin (NTS) in cell line and animal models of CRPC with NED. NTS was acutely induced by androgen deprivation in animal models of prostate cancer (PCa) and activated downstream signaling leading to NED through activation of neurotensin receptor 1 (NTSR1) and neurotensin receptor 3 (NTSR3), but not neurotensin receptor 2 (NTSR2). Our findings also revealed the existence of a CK8+/CK14+ subpopulation in the LNCaP cell line that expresses high levels of both NTSR1 and NTSR3, and displays an enhanced susceptibility to develop neuroendocrine-like phenotypes upon treatment with NTS. More importantly, NTSR1 pathway inhibition prevented the development of NED and castration resistance in vivo. We propose a novel role of NTS in the development of CRPC with NED, and a possible strategy to prevent the onset of NED by targeting the NTS signaling pathway.
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Transdiferenciación Celular/genética , Células Neuroendocrinas/fisiología , Neurotensina/fisiología , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores de Neurotensina/fisiología , Proteínas Adaptadoras del Transporte Vesicular/fisiología , Animales , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Próstata/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/fisiopatologíaRESUMEN
In PTEN-deficient prostate cancers, AKT signaling may be activated upon suppression of androgen receptor signaling. Activation of AKT as well as NF-κB signaling involves a key regulatory protein complex containing PHLPP, FKBP51 and IKKα. Here, we report a critical role of lncRNA PCAT1 in regulating the PHLPP/FKBP51/IKKα complex and progression of castration-resistant prostate cancer (CRPC). Using database queries, bioinformatic analyses, as well as RIP and RNA pull-down assays, we discovered and validated that the lncRNA-PCAT1 perturbs the PHLPP/FKBP51/IKKα complex and activates AKT and NF-κB signaling. Expression of lncRNA-PCAT1 is positively linked to CRPC progression. PCAT1 binds directly to FKBP51, displacing PHLPP from the PHLPP/FKBP51/IKKα complex, leading to activation of AKT and NF-κB signaling. Targeting PCAT1 restores PHLPP binding to FKBP1 leading to suppression of AKT signaling. Preclinical study in a mouse model of CRPC suggests therapeutic potential by targeting lncRNA PCAT1 to suppress CRPC progression. Together, the newly identified PCAT1/FKBP51/IKKα complex provides mechanistic insight in the interplay between AKT, NF-κB and AR signaling in CRPC, and the preclinical studies suggest that a novel role for PCAT1 as a therapeutic target.
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Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , FN-kappa B/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Proteínas Proto-Oncogénicas c-akt/genética , ARN Largo no Codificante/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Animales , Línea Celular Tumoral , Proliferación Celular , Conjuntos de Datos como Asunto , Humanos , Quinasa I-kappa B/genética , Quinasa I-kappa B/metabolismo , Masculino , Ratones , Ratones Desnudos , FN-kappa B/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Neoplasias de la Próstata Resistentes a la Castración/patología , Unión Proteica , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal , Análisis de Supervivencia , Proteínas de Unión a Tacrolimus/genética , Proteínas de Unión a Tacrolimus/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: An increasing number of castration-resistant prostate cancer (CRPC) tumors exhibit neuroendocrine (NE) features. NE prostate cancer (NEPC) has poor prognosis, and its development is poorly understood.Experimental Design: We applied mass spectrometry-based proteomics to a unique set of 17 prostate cancer patient-derived xenografts (PDX) to characterize the effects of castration in vivo, and the proteome differences between NEPC and prostate adenocarcinomas. Genome-wide profiling of REST-occupied regions in prostate cancer cells was correlated to the expression changes in vivo to investigate the role of the transcriptional repressor REST in castration-induced NEPC differentiation. RESULTS: An average of 4,881 proteins were identified and quantified from each PDX. Proteins related to neurogenesis, cell-cycle regulation, and DNA repair were found upregulated and elevated in NEPC, while the reduced levels of proteins involved in mitochondrial functions suggested a prevalent glycolytic metabolism of NEPC tumors. Integration of the REST chromatin bound regions with expression changes indicated a direct role of REST in regulating neuronal gene expression in prostate cancer cells. Mechanistically, depletion of REST led to cell-cycle arrest in G1, which could be rescued by p53 knockdown. Finally, the expression of the REST-regulated gene secretagogin (SCGN) correlated with an increased risk of suffering disease relapse after radical prostatectomy. CONCLUSIONS: This study presents the first deep characterization of the proteome of NEPC and suggests that concomitant inhibition of REST and the p53 pathway would promote NEPC. We also identify SCGN as a novel prognostic marker in prostate cancer.
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Carcinoma Neuroendocrino/genética , Carcinoma Neuroendocrino/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Proteogenómica , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Animales , Carcinoma Neuroendocrino/patología , Ciclo Celular/genética , Línea Celular Tumoral , Biología Computacional/métodos , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Perfilación de la Expresión Génica , Xenoinjertos , Humanos , Masculino , Ratones , Modelos de Riesgos Proporcionales , Prostatectomía , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/cirugía , Proteogenómica/métodosRESUMEN
Mutations in SPOP, the gene most frequently point-mutated in primary prostate cancer, are associated with a high degree of genomic instability and deficiency in homologous recombination repair of DNA but the underlying mechanisms behind this defect are currently unknown. Here we demonstrate that SPOP knockdown leads to spontaneous replication stress and impaired recovery from replication fork stalling. We show that this is associated with reduced expression of several key DNA repair and replication factors including BRCA2, ATR, CHK1 and RAD51. Consequently, SPOP knockdown impairs RAD51 foci formation and activation of CHK1 in response to replication stress and compromises recovery from replication fork stalling. An SPOP interactome analysis shows that wild type (WT) SPOP but not mutant SPOP associates with multiple proteins involved in transcription, mRNA splicing and export. Consistent with the association of SPOP with transcription, splicing and RNA export complexes, the decreased expression of BRCA2, ATR, CHK1 and RAD51 occurs at the level of transcription.
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Replicación del ADN/genética , Inestabilidad Genómica/genética , Proteínas Nucleares/genética , Neoplasias de la Próstata/genética , Proteínas Represoras/genética , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteína BRCA2/genética , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Roturas del ADN de Doble Cadena , Daño del ADN/genética , Reparación del ADN/genética , Regulación de la Expresión Génica/genética , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Mutación , Neoplasias de la Próstata/patología , Empalme del ARN/genética , ARN Mensajero/genética , Recombinasa Rad51/genéticaRESUMEN
Purpose: Bone is the most predominant site of distant metastasis in prostate cancer, and patients have limited therapeutic options at this stage.Experimental Design: We performed a system-wide quantitative proteomic analysis of bone metastatic prostate tumors from 22 patients operated to relieve spinal cord compression. At the time of surgery, most patients had relapsed after androgen-deprivation therapy, while 5 were previously untreated. An extended cohort of prostate cancer bone metastases (n = 65) was used for immunohistochemical validation.Results: On average, 5,067 proteins were identified and quantified per tumor. Compared with primary tumors (n = 26), bone metastases were more heterogeneous and showed increased levels of proteins involved in cell-cycle progression, DNA damage response, RNA processing, and fatty acid ß-oxidation; and reduced levels of proteins were related to cell adhesion and carbohydrate metabolism. Within bone metastases, we identified two phenotypic subgroups: BM1, expressing higher levels of AR canonical targets, and mitochondrial and Golgi apparatus resident proteins; and BM2, with increased expression of proliferation and DNA repair-related proteins. The two subgroups, validated by the inverse correlation between MCM3 and prostate specific antigen immunoreactivity, were related to disease prognosis, suggesting that this molecular heterogeneity should be considered when developing personalized therapies.Conclusions: This work is the first system-wide quantitative characterization of the proteome of prostate cancer bone metastases and a valuable resource for understanding the etiology of prostate cancer progression. Clin Cancer Res; 24(21); 5433-44. ©2018 AACR.
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Neoplasias Óseas/metabolismo , Neoplasias Óseas/secundario , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteoma , Proteómica , Anciano , Biomarcadores de Tumor , Biopsia , Neoplasias Óseas/mortalidad , Neoplasias Óseas/terapia , Terapia Combinada , Biología Computacional/métodos , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Clasificación del Tumor , Pronóstico , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/terapia , Proteómica/métodos , TranscriptomaRESUMEN
Prostate cancer (PCa) is one of the most frequently diagnosed cancer among men in the western societies. Many PCa patients bear tumors that will not threat their lives if left untreated or if treatment is delayed. Our inability for early identification of these patients has resulted in massive overtreatment. Therefore, there is a great need of finding biomarkers for patient stratification according to prognostic risk; as well as there is a need for novel targets that can allow the development of effective treatments for patients that progress to castration-resistant PCa. Most biomarkers in cancer are proteins, including the widely-used prostate-specific antigen (PSA). Recent developments in mass spectrometry allow the identification and quantification of thousands of proteins and posttranslational modifications from small amounts of biological material, including formalin-fixed paraffin-embedded tissues, and biological fluids. Novel diagnostic and prognostic biomarkers have been identified in tissue, blood, urine, and seminal plasma of PCa patients, and new insights in the ethology and progression of this disease have been achieved using this technology. In this review, we summarize these findings and discuss the potential of this technology to pave the way toward the clinical implementation of precision medicine in PCa.
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SOCS2 is a pleiotropic E3 ligase. Its deficiency is associated with gigantism and organismal lethality upon inflammatory challenge. However, mechanistic understanding of SOCS2 function is dismal due to our unawareness of its protein substrates. We performed a mass spectrometry based proteomic profiling upon SOCS2 depletion and yield quantitative data for ~4200 proteins. Through this screen we identify a novel target of SOCS2, the serine-threonine kinase NDR1. Over-expression of SOCS2 accelerates turnover, while its knockdown stabilizes, endogenous NDR1 protein. SOCS2 interacts with NDR1 and promotes its degradation through K48-linked ubiquitination. Functionally, over-expression of SOCS2 antagonizes NDR1-induced TNFα-stimulated NF-κB activity. Conversely, depletion of NDR1 rescues the effect of SOCS2-deficiency on TNFα-induced NF-κB transactivation. Using a SOCS2-/- mice model of colitis we show that SOCS2-deficiency is pro-inflammatory and negatively correlates with NDR1 and nuclear p65 levels. Lastly, we provide evidence to suggest that NDR1 acts as an oncogene in prostate cancer. To the best of our knowledge, this is the first report of an identified E3 ligase for NDR1. These results might explain how SOCS2-deficiency leads to hyper-activation of NF-κB and downstream pathological implications and posits that SOCS2 induced degradation of NDR1 may act as a switch in restricting TNFα-NF-κB pathway.
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Colitis/metabolismo , FN-kappa B/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/química , Proteómica/métodos , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Línea Celular Tumoral , Colitis/genética , Modelos Animales de Enfermedad , Estabilidad de Enzimas , Regulación de la Expresión Génica , Células HEK293 , Humanos , Masculino , Espectrometría de Masas , Ratones , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/deficiencia , Activación Transcripcional , Factor de Necrosis Tumoral alfa/metabolismo , UbiquitinaciónRESUMEN
Castration resistant prostate cancer (CRPC) is a stage of relapse that arises after various forms of androgen ablation therapy (ADT) and causes significant morbidity and mortality. However, the mechanism underlying progression to CRPC remains poorly understood. Here, we report that YAP1, which is negatively regulated by AR, influences prostate cancer (PCa) cell self-renewal and CRPC development. Specifically, we found that AR directly regulates the methylation of YAP1 gene promoter via the formation of a complex with Polycomb group protein EZH2 and DNMT3a. In normal conditions, AR recruits EZH2 and DNMT3a to YAP1 promoter, thereby promoting DNA methylation and the repression of YAP1 gene transcription. Following ADT treatment or when AR activity is antagonized by Bicalutamide or Enzalutamide, YAP1 gene expression is switched on. In turn, YAP1 promotes SOX2 and Nanog expression and the de-differentiation of PCa cells to stem/progenitor-like cells (PCSC), which potentially contribute to disease recurrence. Finally, the knock down of YAP1 expression or the inhibition of YAP1 function by Verteporfin in TRAMP prostate cancer mice significantly suppresses tumor recurrence following castration. In conclusion, our data reveals that AR suppresses YAP1 gene expression through a novel epigenetic mechanism, which is critical for PCa cells self-renewal and the development of CRPC.
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BACKGROUND: Diabetes type 1 is characterized by the failure of beta cells to produce insulin. Suppressor of cytokine signaling (SOCS) proteins are important regulators of the Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway. Previous studies have shown that GH can prevent the development of type I diabetes in mice and that SOCS2 deficiency mimics a state of increased GH sensitivity. METHODOLOGY: The elevated sensitivity of SOCS2-/- mice to GH and possibly to PRL was the rationale to analyze the effects of multiple low dose streptozotocin (MLDSTZ)-induced diabetes in SOCS2-/- mice. RESULTS: We show that 6-month-old SOCS2-/- mice, but not 2-month-old mice, were less sensitive to MLDSTZ-induced diabetes, compared to controls. MLDSTZ treatment induced glucose intolerance in both SOCS2+/+ and SOCS2-/- mice, as shown by glucose tolerance tests, with SOCS2+/+ mice showing a more marked intolerance, compared to SOCS2-/- mice. Furthermore, insulin tolerance tests showed that the SOCS2-/- mice have an improved hypoglycemic response to exogenous insulin, compared to SOCS2+/+ mice. Moreover, in isolated islets, lipotoxic effects on insulin release could partly be overcome by ligands, which bind to GH or PRL receptors. CONCLUSION: Knockdown of SOCS2 makes mice less sensitive to MLDSTZ. These results are consistent with the proposal that elimination of SOCS2 in pancreatic islets creates a state of ß-cell hypersensitivity to GH/PRL that mimics events in pregnancy, and which is protective against MLDSTZ-induced type I diabetes in mice. SOCS2-dependent control of ß-cell survival may be of relevance to islet regeneration and survival in transplantation.
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Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/genética , Eliminación de Gen , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Glucosa/metabolismo , Hormona del Crecimiento/farmacología , Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Ratones , Ratones Endogámicos C57BL , Prolactina/farmacología , Estreptozocina/toxicidad , Proteínas Supresoras de la Señalización de Citocinas/genéticaRESUMEN
BACKGROUND: Clinical management of the prostate needs improved prognostic tests and treatment strategies. Because proteins are the ultimate effectors of most cellular reactions, are targets for drug actions and constitute potential biomarkers; a quantitative systemic overview of the proteome changes occurring during prostate cancer (PCa) initiation and progression can result in clinically relevant discoveries. OBJECTIVES: To study cellular processes altered in PCa using system-wide quantitative analysis of changes in protein expression in clinical samples and to identify prognostic biomarkers for disease aggressiveness. DESIGN, SETTING, AND PARTICIPANTS: Mass spectrometry was used for genome-scale quantitative proteomic profiling of 28 prostate tumors (Gleason score 6-9) and neighboring nonmalignant tissue in eight cases, obtained from formalin-fixed paraffin-embedded prostatectomy samples. Two independent cohorts of PCa patients (summing 752 cases) managed by expectancy were used for immunohistochemical evaluation of proneuropeptide-Y (pro-NPY) as a prognostic biomarker. RESULTS AND LIMITATIONS: Over 9000 proteins were identified as expressed in the human prostate. Tumor tissue exhibited elevated expression of proteins involved in multiple anabolic processes including fatty acid and protein synthesis, ribosomal biogenesis and protein secretion but no overt evidence of increased proliferation was observed. Tumors also showed increased levels of mitochondrial proteins, which was associated with elevated oxidative phosphorylation capacity measured in situ. Molecular analysis indicated that some of the proteins overexpressed in tumors, such as carnitine palmitoyltransferase 2 (CPT2, fatty acid transporter), coatomer protein complex, subunit alpha (COPA, vesicle secretion), and mitogen- and stress-activated protein kinase 1 and 2 (MSK1/2, protein kinase) regulate the proliferation of PCa cells. Additionally, pro-NPY was found overexpressed in PCa (5-fold, p<0.05), but largely absent in other solid tumor types. Pro-NPY expression, alone or in combination with the ERG status of the tumor, was associated with an increased risk of PCa specific mortality, especially in patients with Gleason score ≤ 7 tumors. CONCLUSIONS: This study represents the first system-wide quantitative analysis of proteome changes associated to localized prostate cancer and as such constitutes a valuable resource for understanding the complex metabolic changes occurring in this disease. We also demonstrated that pro-NPY, a protein that showed differential expression between high and low risk tumors in our proteomic analysis, is also a PCa specific prognostic biomarker associated with increased risk for disease specific death in patients carrying low risk tumors. PATIENT SUMMARY: The identification of proteins whose expression change in prostate cancer provides novel mechanistic information related to the disease etiology. We hope that future studies will prove the value of this proteome dataset for development of novel therapies and biomarkers.
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Neuropéptido Y/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Precursores de Proteínas/metabolismo , Proteoma , Biomarcadores de Tumor/metabolismo , Progresión de la Enfermedad , Humanos , Masculino , Espectrometría de Masas , Proteínas Mitocondriales/metabolismo , Clasificación del Tumor , Pronóstico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Regulador Transcripcional ERG/metabolismo , Espera VigilanteRESUMEN
BACKGROUND: Ubiquitination is a highly dynamic and reversible process with a central role in cell homeostasis. Deregulation of several deubiquitinating enzymes has been linked to tumor development but their specific role in prostate cancer progression remains unexplored. METHODS: RNAi screening was used to investigate the role of the ovarian tumor proteases (OTU) family of deubiquitinating enzymes on the proliferation and invasion capacity of prostate cancer cells. RhoA activity was measured in relation with OTUB1 effects on prostate cancer cell invasion. Tumor xenograft mouse model with stable OTUB1 knockdown was used to investigate OTUB1 influence in tumor growth. RESULTS: Our RNAi screening identified OTUB1 as an important regulator of prostate cancer cell invasion through the modulation of RhoA activation. The effect of OTUB1 on RhoA activation is important for androgen-induced repression of p53 expression in prostate cancer cells. In localized prostate cancer tumors OTUB1 was found overexpressed as compared to normal prostatic epithelial cells. Prostate cancer xenografts expressing reduced levels of OTUB1 exhibit reduced tumor growth and reduced metastatic dissemination in vivo. CONCLUSIONS: OTUB1 mediates prostate cancer cell invasion through RhoA activation and promotes tumorigenesis in vivo. Our results suggest that drugs targeting the catalytic activity of OTUB1 could potentially be used as therapeutics for metastatic prostate cancer.
Asunto(s)
Carcinogénesis/metabolismo , Cisteína Endopeptidasas/metabolismo , Invasividad Neoplásica/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Ubiquitinación/fisiología , Animales , Línea Celular , Línea Celular Tumoral , Proliferación Celular/fisiología , Humanos , Masculino , Ratones , Ratones Desnudos , Proteína p53 Supresora de Tumor/metabolismo , Proteína de Unión al GTP rhoA/metabolismoRESUMEN
17ß-estradiol (E2) may interfere with endocrine, metabolic, and gender-differentiated functions in liver in both females and males. Indirect mechanisms play a crucial role because of the E2 influence on the pituitary GH secretion and the GHR-JAK2-STAT5 signaling pathway in the target tissues. E2, through its interaction with the estrogen receptor, exerts direct effects on liver. Hypothyroidism also affects endocrine and metabolic functions of the liver, rendering a metabolic phenotype with features that mimic deficiencies in E2 or GH. In this work, we combined the lipid and transcriptomic analysis to obtain comprehensive information on the molecular mechanisms of E2 effects, alone and in combination with GH, to regulate liver functions in males. We used the adult hypothyroid-orchidectomized rat model to minimize the influence of internal hormones on E2 treatment and to explore its role in male-differentiated functions. E2 influenced genes involved in metabolism of lipids and endo-xenobiotics, and the GH-regulated endocrine, metabolic, immune, and male-specific responses. E2 induced a female-pattern of gene expression and inhibited GH-regulated STAT5b targeted genes. E2 did not prevent the inhibitory effects of GH on urea and amino acid metabolism-related genes. The combination of E2 and GH decreased transcriptional immune responses. E2 decreased the hepatic content of saturated fatty acids and induced a transcriptional program that seems to be mediated by the activation of PPARα. In contrast, GH inhibited fatty acid oxidation. Both E2 and GH replacements reduced hepatic CHO levels and increased the formation of cholesterol esters and triacylglycerols. Notably, the hepatic lipid profiles were endowed with singular fingerprints that may be used to segregate the effects of different hormonal replacements. In summary, we provide in vivo evidence that E2 has a significant impact on lipid content and transcriptome in male liver and that E2 exerts a marked influence on GH physiology, with implications in human therapy.