RESUMEN
Brown fat adipose tissue (BAT) is a therapeutic potential target to improve obesity, diabetes and cold acclimation in mammals. During the long-term cold exposure, the hyperplastic sympathetic network is crucial for BAT the maintain the highly thermogenic status. It has been proved that the sympathetic nervous drives the thermogenic activity of BAT via the release of norepinephrine. However, it is still unclear that how the thermogenic BAT affects the remodeling of the hyperplastic sympathetic network, especially during the long-term cold exposure. Here, we showed that following long-term cold exposure, SCD1-mediated monounsaturated fatty acid biosynthesis pathway was enriched, and the ratios of monounsaturated/saturated fatty acids were significantly up-regulated in BAT. And SCD1-deficiency in BAT decreased the capacity of cold acclimation, and suppressed long-term cold mediated BAT thermogenic activation. Furthermore, by using thermoneutral exposure and sympathetic nerve excision models, we disclosed that SCD1-deficiency in BAT affected the thermogenic activity, depended on sympathetic nerve. In mechanism, SCD1-deficiency resulted in the unbalanced ratio of palmitic acid (PA)/palmitoleic acid (PO), with obviously higher level of PA and lower level of PO. And PO supplement efficiently reversed the inhibitory role of SCD1-deficiency on BAT thermogenesis and the hyperplastic sympathetic network. Thus, our data provided insight into the role of SCD1-mediated monounsaturated fatty acids metabolism to the interaction between thermogenic activity BAT and hyperplastic sympathetic networks, and illustrated the critical role of monounsaturated fatty acids biosynthetic pathway in cold acclimation during the long-term cold exposure.
Asunto(s)
Tejido Adiposo Pardo , Termogénesis , Animales , Tejido Adiposo Pardo/metabolismo , Termogénesis/fisiología , Sistema Nervioso Simpático , Obesidad/metabolismo , Ácidos Grasos Monoinsaturados/metabolismo , Frío , MamíferosRESUMEN
The SLC25A32 dysfunction is associated with neural tube defects (NTDs) and exercise intolerance, but very little is known about disease-specific mechanisms due to a paucity of animal models. Here, we generated homozygous (Slc25a32Y174C/Y174C and Slc25a32K235R/K235R) and compound heterozygous (Slc25a32Y174C/K235R) knock-in mice by mimicking the missense mutations identified from our patient. A homozygous knock-out (Slc25a32-/-) mouse was also generated. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice presented with mild motor impairment and recapitulated the biochemical disturbances of the patient. While Slc25a32-/- mice die in utero with NTDs. None of the Slc25a32 mutations hindered the mitochondrial uptake of folate. Instead, the mitochondrial uptake of flavin adenine dinucleotide (FAD) was specifically blocked by Slc25a32Y174C/K235R, Slc25a32K235R/K235R, and Slc25a32-/- mutations. A positive correlation between SLC25A32 dysfunction and flavoenzyme deficiency was observed. Besides the flavoenzymes involved in fatty acid ß-oxidation and amino acid metabolism being impaired, Slc25a32-/- embryos also had a subunit of glycine cleavage system-dihydrolipoamide dehydrogenase damaged, resulting in glycine accumulation and glycine derived-formate reduction, which further disturbed folate-mediated one-carbon metabolism, leading to 5-methyltetrahydrofolate shortage and other folate intermediates accumulation. Maternal formate supplementation increased the 5-methyltetrahydrofolate levels and ameliorated the NTDs in Slc25a32-/- embryos. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice had no glycine accumulation, but had another formate donor-dimethylglycine accumulated and formate deficiency. Meanwhile, they suffered from the absence of all folate intermediates in mitochondria. Formate supplementation increased the folate amounts, but this effect was not restricted to the Slc25a32 mutant mice only. In summary, we established novel animal models, which enabled us to understand the function of SLC25A32 better and to elucidate the role of SLC25A32 dysfunction in human disease development and progression.
Asunto(s)
Ácido Fólico , Defectos del Tubo Neural , Animales , Humanos , Ratones , Carbono/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Ácido Fólico/metabolismo , Formiatos/metabolismo , Glicina/metabolismo , Mitocondrias/metabolismo , Defectos del Tubo Neural/genética , Defectos del Tubo Neural/metabolismoRESUMEN
BACKGROUND: Serum ceruloplasmin is one of the major diagnostic parameters for Wilson's disease (WD). Age and gender difference of serum ceruloplasmin remain controversy. This study aims to assess diagnostic value of serum ceruloplasmin level for WD in children up to age of 15 years. METHODS: Serum ceruloplasmin levels were measured in 317 WD patients, 21 heterozygotes, 372 healthy control children and 154 non-WD patients with other liver diseases. Receiver operating characteristic (ROC) curve was used to determine the diagnostic accuracy of serum ceruloplasmin for WD in children. RESULTS: Among healthy controls, serum ceruloplasmin level was slightly low in the infants younger than 6 months, and then maintained from 26 to 33 mg/dl after age of 6 months. A total of 8.1% of healthy children had levels of serum ceruloplasmin < 20 mg/dL. Serum ceruloplasmin level was 5.7 ± 4.7 mg/dl in WD patients, and 25.6 ± 5.9 mg/dl in heterozygous carriers. Only 1.9% of WD patients had serum ceruloplasmin levels > 20 mg/dL. Serum ceruloplasmin levels had gender difference, being higher in healthy boys than healthy girls, and higher in asymptomatic WD boys than asymptomatic WD girls (p < 0.01, p < 0.05). Serum ceruloplasmin levels also presented genotypic difference. WD patients with R778L homozygotes exhibited lower levels of serum ceruloplasmin than the patients without R778L (p < 0.05). The ROC curve revealed that serum ceruloplasmin level, at a cutoff value of 16.8 mg/dL, had the highest AUC value (0.990) with a sensitivity of 95.9% and a specificity of 93.6%. CONCLUSIONS: Serum ceruloplasmin is one of sensitive diagnostic biomarkers for WD in children. Gender and genotypic difference of serum ceruloplasmin level should be considered. The cutoff value of serum ceruloplasmin level < 16.8 mg/dL may provide the highest accuracy for diagnosis of WD in children.
Asunto(s)
Ceruloplasmina , Degeneración Hepatolenticular , Adolescente , Niño , Cobre/metabolismo , Femenino , Degeneración Hepatolenticular/diagnóstico , Heterocigoto , Humanos , Lactante , Masculino , Curva ROCRESUMEN
BACKGROUND: Hajdu-Cheney syndrome (HCS) is a rare inherited skeletal disorder caused by pathogenic mutations in exon 34 of NOTCH2. Its highly variable phenotypes make early diagnosis challenging. In this paper, we report a case of early-onset HCS with severe phenotypic manifestations but delayed diagnosis. CASE PRESENTATION: The patient was born to non-consanguineous, healthy parents of Chinese origin. She presented facial anomalies, micrognathia and skull malformations at birth, and was found hearing impairment, congenital heart disease and developmental delay during her first year of life. Her first visit to our center was at 1 year of age due to cardiovascular repair surgery for patent ductus arteriosus (PDA) and ventricular septal defect (VSD). Skull X-ray showed wormian bones. She returned at 7 years old after she developed progressive skeletal anomalies with fractures. She presented with multiple wormian bones, acro-osteolysis, severe osteoporosis, bowed fibulae and a renal cyst. Positive genetic test of a de novo heterozygous frameshift mutation in exon 34 of NOTCH2 (c.6426dupT) supported the clinical diagnosis of HCS. CONCLUSION: This is the second reported HCS case caused by the mutation c.6426dupT in NOTCH2, but presenting much earlier and severer clinical expression. Physicians should be aware of variable phenotypes so that early diagnosis and management may be achieved.
Asunto(s)
Síndrome de Hajdu-Cheney/diagnóstico , Síndrome de Hajdu-Cheney/genética , Fenotipo , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Pueblo Asiatico , Niño , Diagnóstico Precoz , Exones , Femenino , Mutación con Ganancia de Función , Síndrome de Hajdu-Cheney/complicaciones , Humanos , Masculino , Osteoporosis/complicaciones , Enfermedades Raras/complicaciones , Receptor Notch2/genética , Cráneo/patología , Adulto JovenRESUMEN
Wilson disease (WD) is a rare autosomal recessive disorder caused by mutations in the ATP7B gene. Clinical features and mutational analysis of Chinese children with WD at early age were rarely described. Herein, we retrospectively examined 114 children with WD at the mean of 5.9 years old age at diagnosis. Eight patients developed acute liver failure at mean age of 9.7 years old, 4 of whom died. Among the 114 patients, 86.0% were presymptomatic with isolated elevation of transaminases at diagnosis, 99.1% had decreased ceruloplasmin, and 68.4% had urinary copper excretion over 100 µg/24 hr. Bi-allele pathogenic ATP7B mutations were identified in all patients. Among the 60 mutations detected, 10 were novel, including 7 missense mutations (p.I566N, p.T704I, p.C980F, p.G1030 V, p.A1096Q, p.L1327P, and p.L1373F), 1 nonsense mutation (p.K866X), 1 small insertion (p.Y44LfsX2), and 1 small deletion (p.R1118PfsX10). The most frequent mutations were p.R778L, p.P992L, and p.I1148T, which affected 27.2, 25.4, and 20.2% of the 114 WD children, respectively. The patients carrying p.R778L presented a higher rate of acute liver failure than the patients without p.R778L (9.7% vs. 4.8%). These results will be helpful in establishing early diagnosis of WD at the gene level, offering beneficial information for genetic counseling and providing clues to genotype/phenotype correlation of ATP7B mutations.
Asunto(s)
ATPasas Transportadoras de Cobre/genética , Degeneración Hepatolenticular/genética , Fallo Hepático Agudo/genética , Hígado/metabolismo , Mutación , Adolescente , Enfermedades Asintomáticas , Biomarcadores/sangre , Ceruloplasmina/metabolismo , Niño , Preescolar , China , Cobre/orina , Análisis Mutacional de ADN , Femenino , Expresión Génica , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/mortalidad , Degeneración Hepatolenticular/patología , Humanos , Hígado/patología , Fallo Hepático Agudo/diagnóstico , Fallo Hepático Agudo/mortalidad , Fallo Hepático Agudo/patología , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Transaminasas/sangreRESUMEN
Better understanding of metastasis process would allow for the development of effective approaches to treat hepatocellular carcinoma (HCC). Recent literature has highlighted the fundamental role of interaction between tumor cells and their microenvironment components in tumor metastasis. Aberrant expression of epidermal growth factor (EGF) induces highly malignant HCC, and activated EGF/EGFR signaling is correlated with an aggressive phenotype and intrahepatic metastasis. Thus, EGF in the tumor microenvironment may influence the behavior of HCC cells. In this study, for the first time, we studied the expression of EGF in HCCs, and the potential role of EGF in the motility of HCC cells and the underlying mechanisms. It was demonstrated that EGF was highly expressed in HCCs and positively associated with higher tumor grade. In addition, EGF promoted the migration and invasion of HCC cells mainly via induction of fibronectin (FN) in vitro. Mechanistically, EGF simultaneously increased the nuclear translocation and PKC mediated phosphorylation of p65 which could bind to the -356 bp to -259 bp fragment of FN promoter, leading to a markedly increased activity of FN promoter in HCC cells. These results highlight the potential role of EGF in promoting HCC metastasis, demonstrate a novel pathway for regulation of FN expression and provide potential targets for HCC prevention and treatment.
Asunto(s)
Carcinoma Hepatocelular/metabolismo , Movimiento Celular , Factor de Crecimiento Epidérmico/biosíntesis , Fibronectinas/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Factor de Crecimiento Epidérmico/genética , Fibronectinas/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Proteínas de Neoplasias/genéticaRESUMEN
Gaucher disease (GD) is a common lysosomal storage disorder caused by the deficiency of acid ß-glucosidase, due to mutations in the GBA gene. To explore the clinical and molecular characteristics of GD patients from Southern China, GBA gene were analyzed by nest PCR and direct Sanger-sequencing. Novel missense mutations were transiently transfected in COS-7 cells by plasmid system for functional verification. Among the 22 GD patients, 19 patients were classified as type 1 and three as type 2. Over 60% of the type 1 patient had the onset before two years of age and about 42% of them died before three years of age. Six type 1 patients with L444P homozygous genotype, presented with early onset and severe hepatosplenomegaly. Four novel mutations Y22C, F109L, L149F and c.983_990delCCCACTGG were identified. The GBA activities in vitro of novel mutants Y22C, F109L and L149F were 20.2%, 6.9% and 6.5% of the wild-type, respectively. L444P mutation accounted for 47.7% of the mutant alleles. Our results revealed that type 1 GD tends to present with a severe phenotype among southern Chinese. L444P was the most prevalent mutation and L444P homozygous genotype was associated with severe type 1 GD. Three novel missense mutations identified were pathogenic.
Asunto(s)
Enfermedad de Gaucher/genética , Glucosilceramidasa/genética , Mutación , Adolescente , Adulto , Anciano , Animales , Pueblo Asiatico/genética , Células COS , Niño , Preescolar , China/epidemiología , Chlorocebus aethiops , Femenino , Enfermedad de Gaucher/epidemiología , Genotipo , Glucosilceramidasa/química , Homocigoto , Humanos , Lactante , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación Missense , Mutación Puntual , Conformación Proteica , Adulto JovenRESUMEN
Biotinidase (BTD) deficiency is a rare autosomal recessive metabolic disease, which develops neurological and cutaneous symptoms because of the impaired biotin recycling. Pathogenic mutations on BTD gene cause BTD deficiency. Clinical features and mutation analysis of Chinese children with BTD deficiency were rarely described. Herein, for the first time, we reported the clinical features, BTD gene mutations and their functional studies of eight symptomatic children with BTD deficiency from southern China. Fatigue, hypotonia, proximal muscular weakness, hearing deficits, rash and respiratory problems are common clinical phenotype of our patients. Seizures are observed only in patients with profound BTD deficiency. Five novel mutations were detected, among which c.637delC (H213TfsTer51) was found in 50% of our patients and might be considered as a common mutation. In vitro studies confirmed three mild mutations c.1368A>C (Q456H), c.1613G>A (R538H), and c.644T>A (L215H) which retained 10-30% of wild type enzyme activity, and six severe mutations c.235C>T (R79C), c.1271G>C (C424S), c.1412G>A (C471Y), c.637delC (H213TfsTer51), c.395T>G (M132W), c.464T>C (L155P), and c.1493dupT (L498FfsTer13) which retained <10% of wild type enzyme activity. c.1330G>C (D444H) decreased the protein expression but not activity of BTD enzyme, and H213TfsTer51 was structurally damaging while L498FfsTer13 was functionally damaging. These results will be helpful in establishing the definitive diagnosis of BTD deficiency at the gene level, offering appropriate genetic counseling, and providing clues to structure/function relationships of the enzyme.
Asunto(s)
Deficiencia de Biotinidasa/diagnóstico , Deficiencia de Biotinidasa/genética , Biotinidasa/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mutación , Fenotipo , Alelos , Animales , Biomarcadores , Biotinidasa/metabolismo , Deficiencia de Biotinidasa/metabolismo , Línea Celular , Preescolar , China , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Análisis de Secuencia de ADNRESUMEN
OBJECTIVE: To report the 4-year experience of early prenatal diagnosis of lysosomal storage disorders (LSDs) at a center in mainland China. METHOD: Forty-seven pregnancies affected with LSDs were assed using enzymes and/or molecular studies. Prenatal studies were performed on 43 uncultured chorionic villi (CV) samples, two amniotic fluid samples, and two umbilical cord blood samples. RESULTS: Of the 47 fetuses, 23 (48.9%) were determined to normal, 13 (27.7%) to be carriers, and 11 (23.4%) diagnosed as affected. In this cohort, mucopolysaccharidoses (MPS) type II was the most common LSD, followed by Pompe disease and then metachromatic leucodystrophy. In the 17 MPS II cases, the four affected fetuses showed MPS II enzyme activity expression levels of 1.4% to 6.7%, while the enzyme activity levels of the 13 normal fetuses ranged from 72% to 240.4%. In the seven Pompe cases, three fetuses were normal with Pompe enzyme activity expression levels of 20%, 38.8%, and 77.3%, while four carrier pregnancies showed enzyme activity levels of 17.5%, 17.5%, 33.4%, and 13.8%, respectively. CONCLUSION: Based on different enzyme properties in uncultured CV, different prenatal diagnostic strategies should be adopted for MPS II and Pompe disease. Combining enzyme assay and molecular studies in uncultured CV improves the reliability of prenatal diagnosis of LSDs.
Asunto(s)
Muestra de la Vellosidad Coriónica/estadística & datos numéricos , Enfermedades por Almacenamiento Lisosomal/diagnóstico , Adulto , Femenino , Humanos , Enfermedades por Almacenamiento Lisosomal/enzimología , Embarazo , Adulto JovenRESUMEN
Natural killer (NK) cells play an important role in preventing cancer development. NK group 2 member D (NKG2D) is an activating receptor expressed in the membrane of NK cells. Tumour cells expressing NKG2DL become susceptible to an immune-dependent rejection mainly mediated by NK cells. The paradoxical roles of transforming growth factor beta (TGF-ß) in regulation of NKG2DL are presented in many studies, but the mechanism is unclear. In this study, we showed that TGF-ß up-regulated the expression of NKG2DLs in both PC3 and HepG2 cells. The up-regulation of NKG2DLs was characterized by increasing the expression of UL16-binding proteins (ULBPs) 1 and 2. TGF-ß treatment also increased the expression of transcription factor SP1. Knockdown of SP1 significantly attenuated TGF-ß-induced up-regulation of NKG2DLs in PC3 and HepG2 cells, suggesting that SP1 plays a key role in TGF-ß-induced up-regulation of NKG2DLs. TGF-ß treatment rapidly increased SP1 protein expression while not mRNA level. It might be due to that TGF-ß can elevate SP1 stability by activating PI3K/AKT signalling pathway, subsequently inhibiting GSK-3ß activity and decreasing the association between SP1 and GSK-3ß. Knockdown of GSK-3ß further verified our findings. Taken together, these results revealed that AKT/GSK-3ß-mediated stabilization of SP1 is required for TGF-ß induced up-regulation of NKG2DLs. Our study provided valuable evidence for exploring the tumour immune modulation function of TGF-ß.
Asunto(s)
Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Similares a Lectina de Células NK/metabolismo , Factor de Transcripción Sp1/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Regulación hacia Arriba/efectos de los fármacos , Células Hep G2 , Humanos , Modelos Biológicos , Fosfatidilinositol 3-Quinasas/metabolismo , Estabilidad Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacosRESUMEN
Myeloid-derived suppressor cells (MDSC) have been identified as a population of immature myeloid cells that suppress anti-tumor immunity. MDSC are increased in tumor-bearing hosts; thus, depletion of MDSC may enhance anti-tumor immunity. Histone deacetylase inhibitors (HDACi) are chemical agents that are primarily used against hematologic malignancies. The ability of these agents to modulate anticancer immunity has recently been extensively studied. However, the effect of HDACi on MDSC has remained largely unexplored. In the present study, we provide the first demonstration that HDACi treatment decreases MDSC accumulation in the spleen, blood and tumor bed but increases the proportion of T cells (particularly the frequency of IFN-γ- or perforin-producing CD8+ T cells) in BALB/C mice with 4T1 mammary tumors. In addition, HDACi exposure of bone marrow (BM) cells significantly eliminated the MDSC population induced by GM-CSF or the tumor burden in vitro, which was further demonstrated as functionally important to relieve the inhibitory effect of MDSC-enriched BM cells on T cell proliferation. Mechanistically, HDACi increased the apoptosis of Gr-1+ cells (almost MDSC) compared with that of Gr-1- cells, which was abrogated by the ROS scavenger N-acetylcysteine, suggesting that the HDACi-induced increase in MDSC apoptosis due to increased intracellular ROS might partially account for the observed depletion of MDSC. These findings suggest that the elimination of MDSC using an HDACi may contribute to the overall anti-tumor properties of these agents, highlighting a novel property of HDACi as potent MDSC-targeting agents, which may be used to enhance the efficacy of immunotherapeutic regimens.
Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Células Supresoras de Origen Mieloide/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Supresoras de Origen Mieloide/patologíaRESUMEN
BACKGROUND: The interaction between hepatocellular carcinoma (HCC) cells and their microenvironment plays a fundamental role in tumor metastasis. The HCC microenvironment is rich in epidermal growth factor (EGF) and tumor necrosis factor α (TNFα), which may cooperatively, rather than individually, interact with tumor cells to influence their biological behavior. METHODS: Immunohistochemistry was performed to study the expression of EGF and TNFα in HCCs. Western blotting, immunofluorescence, qRT-PCR, wound healing scratch and invasion assay, and chromatin immunoprecipitation assays were used to study the combined roles of EGF and TNFα in the motility of HCC cells in vitro. RESULTS: We demonstrated that both EGF and TNFα were highly expressed in HCCs, and HCCs with higher expression of both EGF and TNFα were more frequently rated as high-grade tumors. In vitro, EGF and TNFα cooperatively promoted the motility of HCC cells mainly via synergistic induction of an extracellular matrix glycoprotein fibronectin (FN). Mechanistically, EGF and TNFα jointly increased the nuclear translocation and PKC mediated phosphorylation of NF-κB/p65 which could bind to the -356bp to -259bp fragment of the FN promoter, leading to a markedly increased activity of the FN promoter in HCC cells. CONCLUSIONS: HCCs with higher expression of both EGF and TNFα were more frequently rated as high-grade tumors. EGF and TNFα cooperatively promoted the motility of HCC cells mainly through NF-κB/p65 mediated synergistic induction of FN in vitro. GENERAL SIGNIFICANCE: These findings highlight the crosstalk between EGF and TNFα in promoting HCC, and provide potential targets for HCC prevention and treatment.
Asunto(s)
Carcinoma Hepatocelular/genética , Factor de Crecimiento Epidérmico/genética , Fibronectinas/biosíntesis , Neoplasias Hepáticas/genética , Factor de Transcripción ReIA/genética , Factor de Necrosis Tumoral alfa/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/genética , Fibronectinas/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , FN-kappa B/genética , FosforilaciónRESUMEN
BACKGROUND: Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development of metastatic cancers. Basic fibroblast growth factor (bFGF) is significantly elevated in metastatic prostate cancers, which has been mentioned mainly to induce EMT in normal cells. However, there is no description about bFGF induced EMT and its underlying mechanism in prostate cancer cells. METHODS: Western blotting, immunofluorescence and qRT-PCR assays were used to study protein or mRNA expression profiles of the EMT. Wound healing scratch, migration and invasion assays were used to test the motility of cells undergoing EMT. More methods were used to explore the underlying mechanisms. RESULTS: We demonstrated that bFGF promoted EMT and motility of human prostate cancer PC-3 cells. Both protein and mRNA expression of Snail were rapidly increased after bFGF treatment. Ectopic expression of Snail triggered EMT and enhanced cell motility in PC-3 cells, and knockdown of Snail almost abolished bFGF induced EMT, suggesting the critical role of Snail. Mechanistic study demonstrated that bFGF promoted the stability, nuclear localization and transcription of Snail by inhibiting the activity of glycogen synthase kinase 3 beta (GSK-3ß) through phosphatidylinositide 3 kinases (PI3K)/protein kinase B (AKT) signaling pathway. CONCLUSIONS: It is concluded that bFGF can promote EMT and motility of PC-3 cells, and AKT/GSK-3ß signaling pathway controls the stability, localization and transcription of Snail which is crucial for this bFGF induced EMT. GENERAL SIGNIFICANCE: To our knowledge, this is the first study to demonstrate that bFGF can induce EMT via AKT/GSK-3ß/Snail signaling pathway in prostate cancer cells.
Asunto(s)
Transición Epitelial-Mesenquimal , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factores de Transcripción/biosíntesis , Línea Celular Tumoral , Movimiento Celular/genética , Factor 2 de Crecimiento de Fibroblastos/genética , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de Señal/genética , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genéticaRESUMEN
Histone deacetylase inhibitors (HDACIs) are now emerging as a new class of anticancer drugs. Some of them have been used in clinical treatment for tumors, most impressively in the hematological tumors. But their single-agent activities in epithelial-derived tumors are limited. The mechanisms of these actions of HDACIs are not yet well understood. In this study, it was found for the first time that HDACIs were able to induce epithelial-mesenchymal transitions (EMT) which is believed to trigger tumor cell invasion and metastasis. We show that HDACIs induce fibroblast-like morphology, up-regulate Snail and Vimentin and down-regulate E-cadherin in epithelial cell-derived tumor cell lines. It demonstrates that HDACI treatment enhances further Snail acetylation and reduces its ubiquitylation, and induces Snail transcription as well as Snail nuclear translocation in CNE2 cells. Snail knockdown by siRNAs prevents the change in cell morphology and Vimentin up-regulation in response to HDACIs. The results suggested that Snail plays an important role in the HDACI-induced EMT. It is very crucial for a better understanding of clinical therapeutical failure of HDACIs in the patients with epithelial cell-derived cancers. Therefore, our results indicate that more attention should be paid to the cancer treatment using HDACIs due to the fact that it will enhance the spread risks of cancer cells to facilitate cancer progression and it is very important to select appropriate drugs for different tumors.
Asunto(s)
Movimiento Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Histona Desacetilasa 1/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Nasofaríngeas/patología , Factores de Transcripción/metabolismo , Western Blotting , Cadherinas/genética , Cadherinas/metabolismo , Histona Desacetilasa 1/genética , Humanos , Inmunoprecipitación , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/metabolismo , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción de la Familia Snail , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Células Tumorales Cultivadas , Regulación hacia Arriba , Vimentina/genética , Vimentina/metabolismo , Cicatrización de HeridasRESUMEN
Cancer metastasis is considered a major challenge in cancer therapy. Recently, epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) signaling has been shown to induce epithelial-mesenchymal transition (EMT) and thereby to promote cancer metastasis. However, the underlying mechanism has not been fully elucidated. We demonstrate that EGF can induce EMT in human prostate and lung cancer cells and thus promote invasion and migration. EGF-induced EMT has been characterized by the cells acquiring mesenchymal spindle-like morphology and increasing their expression of N-cadherin and fibronectin, with a concomitant decrease of E-cadherin. Both protein and mRNA expression of transcription factor Snail rapidly increases after EGF treatment. The knockdown of Snail significantly attenuates EGF-induced EMT, suggesting that Snail is crucial for this process. To determine the way that Snail is accumulated, we demonstrate (1) that EGF promotes the stability of Snail via inhibiting the activity of glycogen synthase kinase 3 beta (GSK-3ß), (2) that protein kinase C (PKC) rather than the phosphatidylinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway is responsible for GSK-3ß inhibition and (3) that GSK-3ß inhibition promotes the transcription of Snail. Taken together, these results reveal that the PKC/GSK-3ß signaling pathway controls both the stability and transcription of Snail, which is crucial for EMT induced by EGF in PC-3 and A549 cells. Our study suggests a novel signaling pathway for Snail regulation and provides a better understanding of growth-factor-induced tumor EMT and metastasis.
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Factor de Crecimiento Epidérmico/farmacología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/metabolismo , Neoplasias/patología , Proteína Quinasa C/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Humanos , Invasividad Neoplásica , Neoplasias/enzimología , Neoplasias/genética , Estabilidad Proteica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacosRESUMEN
BACKGROUND AIMS: Acute liver failure (ALF), a life-threatening disease characterized by the sudden loss of hepatic function, can occur after an accidental or intentional acetaminophen overdose. METHODS: With the use of an ALF mouse model, we examined both the preventive and therapeutic potential of intravenously administered human umbilical cord-derived mesenchymal stromal cells (hUCMSCs). Primary hUCMSCs were purified from freshly collected full-term umbilical cords and intravenously transplanted into BALB/c mice either before and after ALF induced by acetaminophen intoxication. We found that hUCMSCs significantly improved survival rates and relative liver weight of mice in both pre-ALF and post-ALF animals. Correspondingly, serum levels of markers that reflect hepatic injury (ie, aspartate aminotransferase, alanine aminotransferase and total bilirubin) were significantly attenuated in the group receiving hUCMSC therapy. RESULTS: Mechanistically, we found that the protective potential of intravenously administered hUCMSCs was mediated by paracrine pathways that involved antioxidants (glutathione, superoxide dismutase), the reduction of inflammatory agents (tumor necrosis factor-α, interleukin-6) and elevated serum levels of hepatocyte growth factor. CONCLUSIONS: Through these paracrine effects, intravenously administered hUCMSCs reduced hepatic necrosis/apoptosis and enhanced liver regeneration. Thus, our data demonstrate that intravenously administered hUCMSCs may be useful in the prevention or treatment of acetaminophen-induced ALF.
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Acetaminofén/toxicidad , Fallo Hepático Agudo/terapia , Hígado/metabolismo , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Acetaminofén/administración & dosificación , Administración Intravenosa , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Bilirrubina/sangre , Diferenciación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Hígado/patología , Fallo Hepático Agudo/inducido químicamente , Masculino , Ratones Endogámicos BALB C , Cordón Umbilical/citologíaRESUMEN
Circular RNAs (circRNAs), a subclass of non-coding RNAs characterized by covalently closed continuous loops, play a key role in tumorigenesis and aggressiveness. However, the potential molecular mechanism of circRNAs in triple-negative breast cancer (TNBC) remains largely unknown. Exploring their roles and mechanisms in TNBC progression may help identify new diagnostic markers and therapeutic targets. In this study, we found that circ-FOXO3 was dramatically downregulated in TNBC tissues and blood samples from patients with TNBC. Notably, low circ-FOXO3 expression in TNBC tissues and bloods was associated with lymph node metastasis and unfavorable outcomes in patients with TNBC. Overexpression of circ-FOXO3 significantly inhibited the growth, invasion, and metastasis of TNBC cells both in vitro and in vivo. Moreover, we demonstrated that circ-FOXO3 was predominantly expressed in the cytoplasm and directly interacted with Wolf-Hirschhorn syndrome candidate 1 (WHSC1), thereby inhibiting WHSC1 nuclear localization and activity, resulting in the inhibition of H3K36me2 modifications at the Zeb2 promoter, ultimately inhibiting Zeb2 expression and halting TNBC growth and metastasis. Taken together, these results reveal the tumor-suppressive functions of circ-FOXO3 in inhibiting WHSC1-mediated H3K36me2 modification of Zeb2, suggesting that circ-FOXO3 could serve as a potential novel predictive prognostic biomarker and therapeutic target for TNBC.
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MicroARNs , ARN Circular , Neoplasias de la Mama Triple Negativas , Humanos , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/metabolismo , ARN Circular/genética , Neoplasias de la Mama Triple Negativas/metabolismoRESUMEN
Resistance to osimertinib represents a significant challenge for the successful treatment of non-small cell lung cancer (NSCLC) harboring activating mutations in epidermal growth factor receptor (EGFR). N6-methyladenosine (m6A) on mRNAs is critical for various biological processes, yet whether m6A regulates osimertinib resistance of NSCLC remains unknown. In this study, we demonstrated that developing osimertinib-resistant phenotypes depends on m6A reduction resulting from downexpression of m6A methyltransferase METTL14 in EGFR-mutant NSCLCs. Both in vitro and in vivo assay showed that specific knockdown of METTL14 was sufficient to confer osimertinib resistance and elevated expression of METTL14 rescued the efficacy of osimertinib in the resistant NSCLC cells. Mechanistically, METTL14 promoted m6A methylation of pro-apoptotic Bim mRNA and increased Bim mRNA stability and expression, resulting in activating the Bim-dependent pro-apoptotic signaling and thereby promoting osimertinib-induced cell apoptosis. Analysis of clinical samples revealed that decreased expression of METTL14 was observed in osimertinib-resistant NSCLC tissues and significantly associated with a poor prognosis. In conclusion, our study reveals a novel regulatory mechanism by which METTL14-mediated m6A methylation of Bim mRNA inhibited osimertinib resistance of NSCLC cells. It offers more evidences for the involvement of m6A modification in regulation of osimertinib resistance, and provides potential therapeutic targets for novel approaches to overcome the tolerance of osimertinib and other EGFR-TKIs. Implications: This study offers more evidences for the involvement of METTL14-mediated m6A modification in regulation of osimertinib resistance, and provides potential therapeutic targets for novel approaches to overcome the tolerance of osimertinib and other EGFR-TKIs.
RESUMEN
INTRODUCTION: Interleukin-1 beta (IL-1ß) can promote cell migration, invasion and metastasis in various cancer cells. The mechanism of its role in human trophoblast has not been fully investigated. Therefore, we aimed to investigate the expression level of IL-1ß in first trimester decidua and placenta and its potential role in regulation of extravillous trophoblast cell (EVT) invasion and migration. METHODS: First trimester placenta and decidua were collected to study the expression levels of IL-1ß and its receptors by immunohistochemical staining. Primary isolates of first trimester EVT or the HTR-8/SVneo trophoblast like cell line were used to assess migration and invasion. Matrix metalloproteinase levels were assessed by gelatin zymography and ELISA. The phosphorylation profile of signaling pathway proteins was detected with the Proteome Profiler Human Phospho-Kinase Array Kit. Differentially expressed proteins in cells was detected and verified by Western Blot. RESULTS: IL-1ß, its receptors and antagonist are expressed in first trimester placenta and decidua, exogenous IL-1ß stimulates trophoblast cell outgrowth, migration and invasion through the ERK signaling pathway. IL-1ß was significantly increased in the placenta at 6-7 weeks gestation compared with 8-9 weeks gestation (P < 0.0001). Transwell and RTCA assays indicated that IL-1ß stimulates the invasion and migration of EVT. In addition, IL-1ß promoted the phosphorylation of ERK 1/2. It also promoted the expression of MMP2 and MMP9 in EVT as demonstrated by gelatin zymography assay and enzyme linked immunosorbent assay. DISCUSSION: This study demonstrated IL-1ß expression in placenta and decidua, and that it regulates EVT invasion and migration.