RESUMEN
OBJECTIVES: Tumour cell proliferation requires high metabolism to meet the bioenergetics and biosynthetic needs. Dauer in Caenorhabditis elegans is characterized by lower metabolism, and we established an approach with C elegans to find potential tumour therapy targets. MATERIALS AND METHODS: RNAi screening was used to find dauer-related genes, and these genes were further analysed in glp-1(-) mutants for tumour-suppressing testing. The identified tumour-related genes were verified in clinical tumour tissues. RESULTS: The lifespan of glp-1(-) mutants was found to be extended by classical dauer formation signalling. Then, 61 of 287 kinase-coding genes in Caenorhabditis elegans were identified as dauer-related genes, of which 27 were found to be homologous to human oncogenes. Furthermore, 12 dauer-related genes were randomly selected for tumour-suppressing test, and six genes significantly extended the lifespan of glp-1(-) mutants. Of these six genes, F47D12.9, W02B12.12 and gcy-21 were newly linked to dauer formation. These three new dauer-related genes significantly suppressed tumour cell proliferation and thus extended the lifespan of glp-1(-) mutants in a longevity- or dauer-independent manner. The mRNA expression profiles indicated that these dauer-related genes trigged similar low metabolism pattern in glp-1(-) mutants. Notably, the expression of homolog gene DCAF4L2/F47D12.9, TSSK6/W02B12.12 and NPR1/gcy-21 was found to be higher in glioma compared with adjacent normal tissue. In addition, the high expression of TSSK6/W02B12.12 and NPR1/gcy-21 correlated with a worse survival in glioma patients. CONCLUSIONS: Dauer gene screening in combination with tumour-suppressing test in glp-1(-) mutants provided a useful approach to find potential targets for tumour therapy via suppressing tumour cell proliferation and rewiring tumour cell metabolism.
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Caenorhabditis elegans/genética , Glioma/metabolismo , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/metabolismo , Proliferación Celular , Células Germinativas/citología , Glioma/mortalidad , Glioma/patología , Humanos , Estimación de Kaplan-Meier , Longevidad/genética , Mutación , Neoplasias/genética , Pronóstico , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN , Receptores del Factor Natriurético Atrial/metabolismoRESUMEN
The von Hippel-Lindau (VHL) is deficient in â¼70% of clear-cell renal cell carcinomas (ccRCC), which contributes to the carcinogenesis and drug resistance of ccRCC. Here we show that VHL-deficient ccRCC cells present enhanced cytotoxicity of anthracyclines in a hypoxia-inducible factor-independent manner. By subtractive proteomic analysis coupling with RNAi or overexpression verification, aldehyde dehydrogenase 2 (ALDH2) is found to be transcriptionally regulated by VHL and contributes to enhanced anthracyclines cytotoxicity in ccRCC cells. Furthermore, VHL regulates ALDH2 expression by directly binding the promoter of -130 bp to -160 bp to activate the transcription of hepatocyte nuclear factor 4 alpha (HNF-4α). In addition, a positive correlation is found among the protein expressions of VHL, HNF-4α and ALDH2 in ccRCC samples. These findings will deepen our understanding of VHL function and shed light on precise treatment for ccRCC patients.
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Aldehído Deshidrogenasa Mitocondrial/genética , Antraciclinas/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/genética , Regulación hacia Abajo/genética , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Aldehído Deshidrogenasa Mitocondrial/metabolismo , Animales , Antraciclinas/farmacología , Antraciclinas/toxicidad , Carcinoma de Células Renales/patología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Factor Nuclear 4 del Hepatocito/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Renales/patología , Masculino , Ratones Desnudos , Proteínas de Neoplasias/metabolismo , Proteómica , Transcripción Genética/efectos de los fármacosRESUMEN
Obesity is a known cause of gallstone formation and gallstones increases the risk of gallbladder cancer (GBC), but the relation of body mass index (BMI) to GBC remains incompletely understood. To help elucidate the role of obesity in GBC, we performed a meta-analysis of the relationship between BMI and GBC risk. PUBMED and EMBASE databases were searched up to April 17, 2016. Fifteen articles with 5902 cases were identified. Random-effects models and dose-response meta-analyses were used to pool study results. Compared to normal weight, the pooled relative risks (RRs) and the corresponding 95% confidence intervals (CI) of GBC for overweight and obesity is 1.10 (0.98-1.23) and 1.58 (1.43-1.75) respectively. The RRs and 95% CI of overweight and obesity in man are 0.98 (0.90-1.08) and 1.43 (1.19-1.71), while the corresponding RRs in woman are 1.29 (1.08-1.55) and 1.68 (1.41-2.00) when compared to normal weight. A nonlinear dose-response relationship between BMI and risk of GBC was found (P=0.001), and the risk increased by 4% for each 1 kg/m2 increment in BMI. When adjusted for sex, at the point of BMI=25 kg/m2, the RRs (95% CIs) for women and men were 1.13 (1.01-1.25) and 0.98 (0.90-1.07) respectively. The corresponding RRs (95%CIs) at the point of BMI=30 kg/m2 were 1.56(1.39-1.75) vs. 1.24(1.06-1.44). These results suggest that association of obesity and risk of GBC is stronger in woman. Furthermore, overweight is only associated with GBC in woman. A even stricter weight control might be necessary for woman to prevent GBC.
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Neoplasias de la Vesícula Biliar/epidemiología , Obesidad/complicaciones , Sobrepeso/complicaciones , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Distribución por Sexo , Adulto JovenRESUMEN
Nuclear hormone receptors respond to small molecules such as retinoids or steroids and regulate development. Signaling in the conserved p38/PMK-1 MAP kinase pathway regulates innate immunity. In this study, we show that the Caenorhabditis elegans nuclear receptor DAF-12 negatively regulates the defense against pathogens via the downstream let-7 family of microRNAs, which directly target SKN-1, a gene downstream of PMK-1. These findings identify nuclear hormone receptors as components of innate immunity that crosstalk with the p38/PMK-1 MAP kinase pathway.
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Proteínas de Caenorhabditis elegans/inmunología , Caenorhabditis elegans/inmunología , Inmunidad Innata/fisiología , Sistema de Señalización de MAP Quinasas/inmunología , MicroARNs/inmunología , Receptores Citoplasmáticos y Nucleares/inmunología , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/inmunología , Sistema de Señalización de MAP Quinasas/genética , MicroARNs/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/inmunología , Receptores Citoplasmáticos y Nucleares/genética , Factores de Transcripción/genética , Factores de Transcripción/inmunologíaRESUMEN
The proteolytic activation of protein kinase Cδ (PKCδ) generates a catalytic fragment called PKCδ-CF, which induces cell death. However, the mechanisms underlying PKCδ-CF-mediated cell death are largely unknown. On the basis of an engineering leukemic cell line with inducible expression of PKCδ-CF, here we employ SILAC-based quantitative phosphoproteomics to systematically and dynamically investigate the overall phosphorylation events during cell death triggered by PKCδ-CF expression. Totally, 3000 phosphorylation sites were analyzed. Considering the fact that early responses to PKCδ-CF expression initiate cell death, we sought to identify pathways possibly related directly with PKCδ by further analyzing the data set of phosphorylation events that occur in the initiation stage of cell death. Interacting analysis of this data set indicates that PKCδ-CF triggers complicated networks to initiate cell death, and motif analysis and biochemistry verification reveal that several kinases in the downstream of PKCδ conduct these networks. By analysis of the specific sequence motif of kinase-substrate, we also find 59 candidate substrates of PKCδ from the up-regulated phosphopeptides, of which 12 were randomly selected for in vitro kinase assay and 9 were consequently verified as substrates of PKCδ. To our greatest understanding, this study provides the most systematic analysis of phosphorylation events initiated by the cleaved activated PKCδ, which would vastly extend the profound understanding of PKCδ-directed signal pathways in cell death. The MS data have been deposited to the ProteomeXchange with identifier PXD000225.
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Apoptosis , Fosfoproteínas/metabolismo , Proteína Quinasa C-delta/metabolismo , Procesamiento Proteico-Postraduccional , Proteoma/metabolismo , Secuencia de Aminoácidos , Línea Celular Tumoral , Secuencia de Consenso , Proteínas Cullin/metabolismo , Ontología de Genes , Células HEK293 , Humanos , Datos de Secuencia Molecular , Fosfoproteínas/genética , Fosforilación , Mapas de Interacción de Proteínas , Proteoma/genética , Proteómica , Transducción de SeñalRESUMEN
Our previous study has shown that PKCδ stimulates proteasome-dependent degradation of C/EBPα, which partially contributes to PKCδ-mediated apoptosis. However, the molecular interrelationship between these two important proteins is still unknown. In this study, we reported that C/EBPα was phosphorylated by activated PKCδ on three serines, two of which were reported for the first time. Phosphorylated C/EBPα underwent cytoplasmic translocation, which led to the inactivation of its transcriptional activity. Inactive cytoplasmic C/EBPα was finally subjected to proteasome degradation. This work reveals the exquisite molecular events linking activated PKCδ and C/EBPα degradation during cell apoptosis.