Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 298
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Biomed Environ Sci ; 33(1): 72-75, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32029063

RESUMO

Serum samples were tested for Bartonella henselae IgG antibodies using indirect immunofluorescence assays. We then analyzed associated risk factors. Serum samples were considered positive when reactive at a dilution of more than 1:320. Differences between groups and risk factors associated with Bartonella exposure were statistically analyzed using Chi-square tests and the generalized linear model. 122 of 1,260 samples (9.68%) were positive for B. henselae infection. The infection rate ranged from 0% to 30.43% and differed significantly among age groups ( P < 0.01); infection rate in the 50-59 years group was significantly higher than that in other age groups. The seroprevalence of Bartonella varied significantly among sites within the four provinces, and the infection rate of field workers was significantly higher than that of urban workers.

2.
Nanoscale ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32016276

RESUMO

The well-known Stöber method has been widely used to synthesize nonporous silica nanospheres (NPs), however, in the absence of surfactant templates, the synthesis of mesoporous silica nanospheres (MSNs) has not been achieved. Herein, in the absence of organic surfactant templates, by a simple premixing of three components tetraethoxysilane-water-ethanol (TEOS-H2O-EtOH) with a precise molar ratio, the parent silica nanoparticles with a low condensation degree and controlled particle size can be readily obtained. Subsequently, via a simple two-step post-treatment, the obtained MSNs exhibited a high surface area (ca. 500 m2 g-1), accessible mesopores (3.0 nm), and a large pore volume (0.87 mL g-1), similar to those of MCM-41 and SBA-15 silicas. The unique self-templating role of the 'pre-Ouzo' effect of ternary surfactant-free TEOS-H2O-EtOH systems was proposed to understand the formation of mesoporosity.

3.
Mol Oncol ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31925912

RESUMO

Bone metastasis is associated with cancer-related death in patients with prostate cancer (PCa). Long noncoding RNAs (lncRNAs) play critical roles in tumor progression of PCa. Nevertheless, the biological function of lncRNAs in PCa bone metastasis remains unclear. PCAT7 was identified as a bone metastasis-related lncRNA via analyzing TCGA dataset. Meanwhile, PCAT7 was found to be elevated in primary PCa tissues with bone metastasis and associated with bone metastasis status and poor prognosis of patients with PCa. Functionally, our results reveal that PCAT7 overexpression promotes PCa bone metastasis in vivo, as well as migration, invasion, and EMT of PCa cells in vitro; on the contrary, PCAT7 knockdown has an inverse effect. Mechanistically, PCAT7 activates TGF-ß/SMAD signaling by upregulating TGFBR1 expression via sponging miR-324-5p. In turn, TGF-ß signaling forms a positive feedback loop with PCAT7 via SMAD3/SP1 complex-induced PCAT7 upregulation. Finally, the clinical positive correlation between PCAT7 and TGFBR1 and TGF-ß signaling activity, and the negative association with miR-324-5p are further demonstrated in PCa tissues and clinical primary PCa cells. This study reveals a novel mechanism that is responsible for the constitutive activation of TGF-ß signaling in PCa bone metastasis, implying that PCAT7 can act as a potential therapeutic target against bone metastasis of PCa via disrupting the constitutive active loop between PCAT7 and TGF-ß signaling.

4.
Oncogene ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988454

RESUMO

Circulating tumor cells (CTC) disseminating is an important cause of distant metastasis. However, the mechanism involved in increasing the numbers of CTCs in breast cancer is unclear. Herein, Zinc finger protein 367 (ZNF367) was identified as a potential prometastatic gene in an integrative breast cancer datasets. ZNF367 was upregulated in breast cancer tissues and cell lines, and significantly correlated with poorer metastasis-free and overall survivals in patients. ZNF367 promoted tumor metastasis accompanied with increase of CTC numbers. Mechanistically, ZNF367 interacted with chromatin remodeling protein BRG1 and transcriptionally activated CIT and TP53BP2, leading to the inhibition of the Hippo pathway and activation of YAP1, which gave rise to the resistance of anoikis and increased CTCs in the blood circulation. More importantly, administration of a YAP1 inhibitor Verteporfin resensitized ZNF367-overexpressing breast cancer cells to anoikis and abrogated metastasis. Our findings addressed the importance of ZNF367 in breast cancer as a prognostic biomarker and offered a potential therapeutic strategy for the treatment of a subset of metastatic breast cancer with ZNF367 overexpression.

5.
Ann Hepatol ; 19(1): 79-87, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31548168

RESUMO

INTRODUCTION AND OBJECTIVES: Necroptosis and endoplasmic reticulum (ER) stress has been implicated in acute and chronic liver injury. Activated eukaryotic initiation factor 2 alpha (eIF2α) attenuates protein synthesis and relieves the load of protein folding in the ER. In this study, we aimed to analyze the impact of eIF2α phosphorylation on hepatocyte necroptosis in acute liver injury. MATERIALS AND METHODS: Male BALB/c mice were injected with tunicamycin or d-galactosamine, and LO2 cells were incubated with tunicamycin to induce acute liver injury. 4-Phenylbutyric acid (PBA) and salubrinal were used to inhibit ER stress and eIF2α dephosphorylation, respectively. We analyzed the eIF2α phosphorylation, ER stress, and hepatocyte necroptosis in mice and cells model. RESULTS: Tunicamycin or d-galactosamine significantly induced ER stress and necroptosis, as well as eIF2α phosphorylation, in mice and LO2 cells (p<0.05). ER stress aggravated tunicamycin-induced hepatocyte necroptosis in mice and LO2 cells (p<0.05). Elevated eIF2α phosphorylation significantly mitigated hepatocyte ER stress (p<0.05) and hepatocyte necroptosis in mice (34.37±3.39% vs 22.53±2.18%; p<0.05) and LO2 cells (1±0.11 vs 0.33±0.05; p<0.05). Interestingly, tumor necrosis factor receptor (TNFR) 1 protein levels were not completely synchronized with necroptosis. TNFR1 expression was reduced in d-galactosamine-treated mice (p<0.05) and cells incubated with tunicamycin for 12 and 24h (p<0.05). ER stress partially restored TNFR1 expression and increased necroptosis in tunicamycin-incubated cells (p<0.05). CONCLUSIONS: These results imply that ER stress can mediate hepatocyte necroptosis independent of TNFR1 signaling and elevated eIF2α phosphorylation can mitigate ER stress during acute liver injury.

6.
Nat Commun ; 10(1): 5424, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822675

RESUMO

Due to a lack of Mesozoic fossil records, the origins and early evolution of feather-feeding behaviors by insects are obscure. Here, we report ten nymph specimens of a new lineage of insect, Mesophthirus engeli gen et. sp. nov. within Mesophthiridae fam. nov. from the mid-Cretaceous (ca. 100 Mya) Myanmar (Burmese) amber. This new insect clade shows a series of ectoparasitic morphological characters such as tiny wingless body, head with strong chewing mouthparts, robust and short antennae having long setae, legs with only one single tarsal claw associated with two additional long setae, etc. Most significantly, these insects are preserved with partially damaged dinosaur feathers, the damage of which was probably made by these insects' integument-feeding behaviors. This finding demonstrates that feather-feeding behaviors of insects originated at least in mid-Cretaceous, accompanying the radiation of feathered dinosaurs including early birds.

7.
PLoS One ; 14(12): e0225502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826006

RESUMO

Two new genera and species of Elateridae, Megalithomerus magohalmii gen. et sp. nov. and Koreagrypnus jinju gen. et sp. nov., are described based on two pairs of fossils from the late Early Cretaceous Jinju Formation in Jinju City, South Korea. Both Megalithomerus and Koreagrypnus represent the youngest occurrences of an extinct elaterid subfamily, Protagrypninae. Megalithomerus magohalmii is the largest known fossil elaterid. These newly described elaterids provide a better understanding of the morphological diversity and occurrence of Protagrypninae through geologic time.

8.
J Pharm Pharmacol ; 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31826333

RESUMO

OBJECTIVES: Withanolides are a group of modified C28 ergostane-type steroids with a C-22, C-26 δ-lactone side chain or a C-23, C-26 γ-lactone side chain. They enjoy a limited distribution in the plant kingdom and predominantly occur in several genera of Solanaceae. Of which, the genus Physalis is an important resource for this type of natural molecules. The present review aims to comprehensively illustrate the structural characteristics and classification of withanolides, and particularly focus on the progression on phytochemical and pharmacological aspects of withanolides from Physalis ranging from January 2015 to June 2019. KEY FINDINGS: Approximately 351 natural withanolides with novel and unique structures have so far been identified from genus Physalis, mainly isolated from the species of P. angulata and P. peruviana. Withanolides demonstrated diverse biological activity, such as anticancer, anti-inflammatory, antimicrobial, immunoregulatory, trypanocidal and leishmanicidal activity. Their observed pharmacological functions supported the uses of Physalis species in traditional or folk medicines. SUMMARY: Due to their unique structure skeleton and potent bioactivities, withanolides are regarded to be promising drug candidates, particularly for developing anticancer and anti-inflammatory agents. Further investigations for discovering novel withanolides of genus Physalis, exploiting their pharmacological values and evaluating their potency as therapeutic agents are significant work.

9.
Urol Int ; : 1-6, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31851995

RESUMO

INTRODUCTION: To evaluate the potential predictive value of the Mayo Adhesive Probability (MAP) score combined with the RENAL score for intraoperative outcomes in retroperitoneal laparoscopic nephron-sparing surgery (NSS) in an Eastern Asian population. METHODS: An initial of 388 patients undergoing retroperitoneal laparoscopic NSS were identified. MAP and RENAL scores were calculated according to CT and a logistic regression model was adopted as a combination of the RENAL score and the MAP score. RESULTS: A total of 293 patients were included. The overall intraoperative complication rate was 7.5% (21 cases). The MAP score was found to correlate with operation time (OT; r = 0.169), estimated blood loss (EBL; r = 0.318), and intraoperative complications (r = 0.242). The RENAL score was correlated with warm is-chemia time (r = 0.503), OT (r = 0.334), intraoperative complications (r = 0.178), and EBL (r = 0.218). The MAP score and the RENAL score were reliable predictors of overall intraoperative complications, with areas under the curve (AUC) of 0.728 and 0.759, respectively. After combination of these 2 scores, the AUC of overall intra-operative complications was improved with statistical significance (AUC = 0.847, combination vs. RENAL score: p = 0.044 < 0.05; combination vs. MAP score: p = 0.005 < 0.05). CONCLUSION: The MAP score is an important predictor of EBL, OT, and intraoperative complications in retroperitoneal laparoscopic NSS and its combination with the RENAL score showed a superior predictive value compared to a single score in overall intraoperative complications. The MAP score might be considered in preoperative radiologic aspects as regularly as the RENAL score.

10.
Sci Rep ; 9(1): 20245, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882985

RESUMO

Ice thickness has a great influence on glacial movement and ablation. Over the course of the change in thickness, area and external climate, the dynamic process of how glaciers change and whether a glacier's changes in melting tend to be stable or irregular is a problem that needs to be studied in depth. In our study, the changes in the dynamic process of the No. 8 Glacier in Hei Valley (H8) under the conditions of different thicknesses in 1969 and 2009 were simulated based on the Full-Stokes code Elmer/Ice (http://www.csc.fi/elmer/). The results were as follows: (1) The thickness reduction in glaciers would lead to a decrease in ice surface tension and basal pressure and friction at the bottom, and the resulting extensional and compressional flow played an important role in the variations in glacial velocity. (2) The force at the bottom of the glacier was key to maintaining the overall stress balance, and the glaciers that often melted and collapsed in bedrock were more easily destroyed by the overall force balance and increased change rate of glacial thaw. (3) Temperature changes at different altitudes affected the ice viscous force. The closer the ice surface temperature was to the melting point, the greater the influence of temperature changes on the ice viscous force and ice surface velocity. Finally, we used the RCP 4.8 and 8.5 climate models to simulate the changes in H8 over the next 40 years. The results showed that with some decreases in ice surface compression and tension, the gravity component changes caused by local topography begin to control the ice flow movement on the surface of glacier, and melting of the glacial surface will appear as an irregular change. The simulation results further confirmed that the fluctuation in glacial dynamic characteristics could be attributed to the change in the gravity component caused by ablation.

11.
Free Radic Biol Med ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31760092

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease resulted from airflow obstructions, and there is a driving requirement for novel and effective preventive and therapeutic agents of COPD. Nuclear factor-erythroid 2-related factor 2 (Nrf2) has been regarded to be a promising therapeutic target for COPD. Resveratrol is a natural Nrf2 activator with antioxidant and anti-inflammatory properties, however, its application is limited by its relative low efficiency and poor bioavailability. Herein, based on the skeleton of resveratrol, trans-4,4'-dihydroxystilbene (DHS) has been firstly identified to be an Nrf2 activator, which is more potent than the well-known sulforaphane (SF) and resveratrol. Our results indicate that DHS blocks Nrf2 ubiquitylation through specifically reacting with Cys151 cysteine in Keap1 protein to activate Nrf2-regulated defensive response, and thus enhances intracellular antioxidant capability. Furthermore, DHS relieves lipopolysaccharide (LPS)-stimulated inflammatory response via inhibition of NF-κB. Importantly, DHS significantly ameliorates pathological alterations (e.g. infiltration of leukocytes and fibrosis), downregulates the levels of oxidant biomarkers malondialdehyde (MDA) and 8-oxo-7,8-dihydro-2'-deoxyguanosin (8-oxo-dG), and inhibits the overproductions of inflammatory mediators [e.g. tumor necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and matrix metalloproteinase-9 (MMP-9)] in a cigarette smoke (CS)-induced pulmonary impairment mice model. Taken together, this study demonstrates that DHS attenuates the CS-induced pulmonary impairments through inhibitions of oxidative stress and inflammatory response targeting Nrf2 and NF-κB in vitro and in vivo, and could be developed into a preventive agent against pulmonary impairments induced by CS.

12.
Mol Ther Nucleic Acids ; 18: 567-579, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31678733

RESUMO

The prime issue derived from prostate cancer (PCa) is its high prevalence to metastasize to bone. MicroRNA-204-5p (miR-204-5p) has been reported to be involved in the development and metastasis in a variety of cancers. However, the clinical significance and biological functions of miR-204-5p in bone metastasis of PCa are still not reported yet. In this study, we find that miR-204-5p expression is reduced in PCa tissues and serum sample with bone metastasis compared with that in PCa tissues and serum sample without bone metastasis, which is associated with advanced clinicopathological characteristics and poor bone metastasis-free survival in PCa patients. Moreover, upregulation of miR-204-5p inhibits the migration and invasion of PCa cells in vitro, and importantly, upregulating miR-204-5p represses bone metastasis of PCa cells in vivo. Our results further demonstrated that miR-204-5p suppresses invasion, migration, and bone metastasis of PCa cells via inactivating nuclear factor κB (NF-κB) signaling by simultaneously targeting TRAF1, TAB3, and MAP3K3. In clinical PCa samples, miR-204-5p expression negatively correlates with TRAF1, TAB3, and MAP3K3 expression and NF-κB signaling activity. Therefore, our findings reveal a new mechanism underpinning the bone metastasis of PCa, as well as provide evidence that miR-204-5p might serve as a novel serum biomarker in bone metastasis of PCa. This study identifies a novel functional role of miR-204-5p in bone metastasis of prostate cancer and supports the potential clinical value of miR-204-5p as a serum biomarker in bone metastasis of PCa.

13.
Zootaxa ; 4691(2): zootaxa.4691.2.4, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31719403

RESUMO

A new genus and species of rhagionids with a long proboscis, Elliprhagio macrosiphonius gen. et sp. nov., is described from the Middle Jurassic Jiulongshan Formation in Daohugou, Inner Mongolia, China, which is considered to be the earliest hematophagous rhagionid described hitherto according to the typically piercing and sucking mouthparts. All previously documented rhagionids from northeastern China are reviewed a key to genera of Rhagionidae from Daohugou is provided for the first time. The genus Daohugorhagio Zhang, 2013 is considered as a new synonym of Trichorhagio Zhang, 2013.


Assuntos
Charadriiformes , Dípteros , Animais , China , Fósseis
14.
Zootaxa ; 4585(2): zootaxa.4585.2.8, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31716173

RESUMO

A new genus and species of Cydnidae, Punctacorona triplosticha gen. et sp. nov. (Heteroptera: Pentatomomorpha) is described and illustrated from Myanmar amber. This new genus is established based on its forewing anterior margin angulated, clavus narrow, with three rows of distinct punctures, metapleuron neighboring to posterior margin of evaporatorium carinate. A comparison between the new species and the Chilamnestocoris mixtus Lis et al. 2018 from Myanmar is provided.


Assuntos
Gastrópodes , Heterópteros , Âmbar , Animais , Fósseis , Mianmar
15.
Zootaxa ; 4613(2): zootaxa.4613.2.11, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31716420

RESUMO

A new genus and species of Ithonidae, Puripolystoechotes pumilus gen. et sp. nov., is described from the Middle Jurassic of Inner Mongolia, China. The new genus is distinguished by possessing a hind wing with a simple humeral vein, only three ra-rp crossveins, M forked slightly distal to origin of RP1, and wing membrane without color pattern. This is the third ithonid genus from this locality, showing interesting morphological similarity with the other ithonids from the same locality and period.


Assuntos
Fósseis , Holometábolos , Animais , China , Insetos , Asas de Animais
16.
Zootaxa ; 4661(1): zootaxa.4661.1.10, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31716724

RESUMO

A new genus with a new species, Lasiopsychops impunctatus gen. et sp. nov., and a new species, Electropsychops oligophlebius sp. nov., of silky lacewings in Psychopsidae are described from mid-Cretaceous Burmese amber. Lasiopsychops gen. nov. has typical characters of the extant Psychopsidae, i.e., broad triangular forewing, broad costal space, presence of the vena triplica and the paired ectoprocts and gonocoxites 9 of female genitalia, implying its close affinity with the extant lineages of Psychopsidae. The new findings of the Cretaceous psychopsids enhance our knowledge on the diversity and evolution of Psychopsidae during the Mesozoic.


Assuntos
Âmbar , Seda , Animais , Feminino , Fósseis , Holometábolos , Insetos
17.
ACS Appl Mater Interfaces ; 11(44): 41178-41187, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31600433

RESUMO

Lithium nickel manganese cobalt oxide (NMC) materials, with low cost and high energy density, are considered to be among the most promising cathode materials for Li-ion batteries (LIBs). However, several issues have hindered their further deployment, particularly for high-powered applications, including limited rate capability, capacity loss during cycling (especially at high temperatures and high voltages), and difficulty in reproducibly preparing the desired particle morphology. In this work, we have developed a robust LiNi0.33Mn0.33Co0.33O2 cathode material (NMC-111) capable of high-rate performance for LIBs. Our high power NMC-111 (HP-NMC) cathode materials showed significantly enhanced electrochemical performance, relative to a commercial NMC-111 (c-NMC), with discharge capacities of 138 and 131 mAh/g at high current rates of 20 and 30 C, respectively. The material also exhibited enhanced cycling stability under both room temperature and at 50 °C. We ascribe the high performance of our material to a unique crystalline microstructure observed by electron microscopy characterization, which showed preferential orientation of the Li-diffusing channels radially outward. This HP-NMC material achieved one of the highest performance metrics among NMC materials reported to date, especially for high-powered electric vehicles.

18.
Ear Hear ; 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31567561

RESUMO

OBJECTIVES: The purpose of this study was to develop a deep-learning framework for the diagnosis of chronic otitis media (COM) based on temporal bone computed tomography (CT) scans. DESIGN: A total of 562 COM patients with 672 temporal bone CT scans of both ears were included. The final dataset consisted of 1147 ears, and each of them was assigned with a ground truth label from one of the 3 conditions: normal, chronic suppurative otitis media, and cholesteatoma. A random selection of 85% dataset (n = 975) was used for training and validation. The framework contained two deep-learning networks with distinct functions: a region proposal network for extracting regions of interest from 2-dimensional CT slices; and a classification network for diagnosis of COM based on the extracted regions. The performance of this framework was evaluated on the remaining 15% dataset (n = 172) and compared with that of 6 clinical experts who read the same CT images only. The panel included 2 otologists, 3 otolaryngologists, and 1 radiologist. RESULTS: The area under the receiver operating characteristic curve of the artificial intelligence model in classifying COM versus normal was 0.92, with sensitivity (83.3%) and specificity (91.4%) exceeding the averages of clinical experts (81.1% and 88.8%, respectively). In a 3-class classification task, this network had higher overall accuracy (76.7% versus 73.8%), higher recall rates in identifying chronic suppurative otitis media (75% versus 70%) and cholesteatoma (76% versus 53%) cases, and superior consistency in duplicated cases (100% versus 81%) compared with clinical experts. CONCLUSIONS: This article presented a deep-learning framework that automatically extracted the region of interest from two-dimensional temporal bone CT slices and made diagnosis of COM. The performance of this model was comparable and, in some cases, superior to that of clinical experts. These results implied a promising prospect for clinical application of artificial intelligence in the diagnosis of COM based on CT images.

19.
Theranostics ; 9(21): 6063-6079, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534537

RESUMO

Background: The reciprocal repressive loop between ZEB1 and miRNAs has been extensively reported to play an important role in tumor progression and metastasis of various human tumor types. The aim of this study was to elucidate the role and the underlying mechanism of the double-negative feedback loop between ZEB1and miR-33a-5p in bone metastasis of prostate cancer (PCa). Methods: miR-33a-5p expression was examined in 40 bone metastatic and 165 non-bone metastatic PCa tissues by real-time PCR. Statistical analysis was performed to evaluate the clinical correlation between miR-33a-5p expression and clinicopathological characteristics, and overall and bone metastasis-free survival in PCa patients. The biological roles of miR-33a-5p in bone metastasis of PCa were investigated both by EMT and the Transwell assay in vitro, and by a mouse model of left cardiac ventricle inoculation in vivo. siRNA library, real-time PCR and chromatin immunoprecipitation (ChIP) were used to identify the underlying mechanism responsible for the decreased expression of miR-33a-5p in PCa. Bioinformatics analysis, Western blotting and luciferase reporter analysis were employed to examine the relationship between miR-33a-5p and its potential targets. Clinical correlation of miR-33a-5p with its targets was examined in human PCa tissues and primary PCa cells. Results: miR-33a-5p expression was downregulated in PCa tissues with bone metastasis and bone-derived cells, and low expression of miR-33a-5p strongly and positively correlated with advanced clinicopathological characteristics, and shorter overall and bone metastasis-free survival in PCa patients. Upregulating miR-33a-5p inhibited, while silencing miR-33a-5p promoted EMT, invasion and migration of PCa cells. Importantly, upregulating miR-33a-5p significantly repressed bone metastasis of PC-3 cells in vivo. Our results further revealed that recurrent ZEB1 upregulation induced by copy number gains transcriptionally inhibited miR-33a-5p expression, contributing to the reduced expression of miR-33a-5p in bone metastatic PCa tissues. In turn, miR-33a-5p formed a double negative feedback loop with ZEB1 in target-independent manner, which was dependent on TGF-ß signaling. Finally, the clinical negative correlations of miR-33a-5p with ZEB1 expression and TGF-ß signaling activity were demonstrated in PCa tissues and primary PCa cells. Conclusion: Our findings elucidated that copy number gains of ZEB1-triggered a TGF-ß signaling-dependent miR-33a-5p-mediated negative feedback loop was highly relevant to the bone metastasis of PCa.

20.
J Exp Clin Cancer Res ; 38(1): 391, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488180

RESUMO

BACKGROUND: Clinically, prostate cancer (PCa) exhibits a high avidity to metastasize to bone. Myc-associated zinc-finger protein (MAZ) is a well-documented oncogene involved in the progression and metastasis of multiple cancer types, even in PCa. However, the clinical significance and biological roles of MAZ in bone metastasis of PCa remain unclear. METHODS: MAZ expression was examined in PCa tissues with bone metastasis, PCa tissues without bone metastasis and metastatic bone tissues by real-time PCR and immunohistochemistry (IHC), respectively. Statistical analysis was performed to evaluate the clinical correlation between MAZ expression and clinicopathological features and bone metastasis-free survival in PCa patients. Biological roles of MAZ in bone metastasis of PCa were investigated both in vitro by transwell assay, and in vivo by a mouse model of left cardiac ventricle inoculation. The bioinformatics analysis, western blot, pull-down assays, chromatin immunoprecipitation (ChIP) and luciferase reporter assays were applied to demonstrate and examine the relationship between MAZ and its potential downstream signalling pathway. TaqMan copy number assay was performed to identify the underlying mechanism responsible for MAZ overexpression in PCa tissues. RESULTS: MAZ expression is elevated in PCa tissues with bone metastasis compared with that in PCa tissues without bone metastasis, and is further increased in metastatic bone tissues. High expression of MAZ positively correlates with poor overall and bone metastasis-free survival in PCa patients. Upregulating MAZ elevates, while silencing MAZ represses the invasion and migration abilities of PCa cells in vitro and bone metastasis ability in vivo. Our results further reveal that MAZ promotes bone metastasis of PCa dependent on KRas signalling, although MAZ transcriptionally upregulates KRas and HRas expression, where the Ral guanine nucleotide exchange factor (RalGEF) signaling is responsible for the different roles of KRas and HRas in mediating the pro-bone metastasis of MAZ in PCa. Finally, our results indicate that recurrent gains contribute to MAZ overexpression in a small portion of PCa tissues. CONCLUSION: These results indicate that the MAZ/Kras/ RalGEF signalling axis plays a crucial role in promoting PCa cell bone metastasis, suggesting a potential therapeutic utility of MAZ in bone metastasis of PCa.


Assuntos
Neoplasias Ósseas/secundário , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Transcrição/metabolismo , Fator ral de Troca do Nucleotídeo Guanina/metabolismo , Idoso , Animais , Biópsia , Neoplasias Ósseas/mortalidade , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Modelos Biológicos , Gradação de Tumores , Estadiamento de Neoplasias , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA