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1.
Molecules ; 28(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37446624

RESUMO

BiOCl/graphene aerogel graphene (BGA) was successfully obtained by in situ hydrothermal synthesis, and the chemical, structural, morphological, and photocatalytic properties were systematically characterized. BGA with the doping amount of BiOCl at 20% (BGA-4) exhibited the optimal activation efficiency for persulfate (PDS) on the degradation of methyl orange (MO) under simulated sunlight (SSL) illumination as compared to the pure graphene (GA) and aerogel composites with different BiOCl content. The influence of various reaction parameters on the MO removal efficiency, such as the reaction system, catalyst activator dose, PDS concentration, BiOCl doping amount, and the initial pH of the solution, was investigated. Under optimum conditions, the catalytic efficiency of BiOCl-doped GA with the mass ratio of 20% (BGA-4) was 5.61 times that of GA. The strengthening effect of BGA-4 benefited from the synergistic effect of 1O2, O2·- and the generation and rapid electron transfer of photo-induced electron (e-) in the BGA-4/SSL/PDS system. Considering the superior stability and recyclability of BGA-4, the BGA-4/SSL/PDS system exhibits great potential in actual wastewater treatment.


Assuntos
Grafite , Grafite/química , Luz Solar , Compostos Azo , Transporte de Elétrons
2.
J Nanosci Nanotechnol ; 21(1): 181-194, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213622

RESUMO

With continuous improvements in nanotechnology, the development of micro/nanoscale pores and fractures in reservoirs can be more clearly identified, and great progress has been made in tight sandstone and shale. Bedrock has an ultralow porosity and is a reservoir with low permeability. To study the characteristics of micro/nanoscale pore development and reveal their petroleum significance in the eastern segment of the Altun Piedmont, research has been conducted with the use of cathodoluminescence, field emission scanning electron microscopy and energy spectrum analysis, formation microresistivity image logging, high-pressure mercury injection and nuclear magnetic logging. The results have shown that the porosity of the bedrock reservoir in the eastern segment of the Altun Piedmont, as measured by helium injection and nuclear magnetic logging, is between 0.004% and 9.76%, the average porosity is between 1.663% and 3.844%, and the permeability is between the maximum of 0.002 mD and 33.239 mD. The average permeability is between 0.02 mD and approximately 3.836 mD. Micro/nanopores are generally developed, with the majority being intragranular micro/nanopores, intercrystalline micro/nanopores and microcracks, as summarized by the field emission scanning electron microscopy and energy dispersive spectroscopy analysis. Four differently sized pores develop: micropores account for approximately 20%, transition pores account for approximately 30%, and mesopores and macropores account for approximately 25% each. The pore throat development below 100 nm is greater than 50% according to the collation of experimental data from high-pressure mercury intrusion; therefore, micro/nanopores are the main storage space in the study area, and the gas logging shows good results. Micro/nanopores are also one of the main reservoir spaces of bedrock reservoirs in conjunction with the conventional reservoir space, and thus, micro/nanopores have important petroleum significance.

3.
Resuscitation ; 157: 141-148, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33191208

RESUMO

THE AIM OF THE STUDY: To identify the prognostic factors and effects of implantable cardioverter-defibrillators (ICDs) in out-of-hospital cardiac arrest (OHCA) patients with ICDs because the clinical characteristics and outcomes of OHCA patients with ICDs are unknown. METHODS: The North American Resuscitation Outcomes Consortium (ROC) Cardiac Epistry Version 3 dataset was analyzed. Eligible patients were divided into OHCA patients with and without ICDs. Multivariable regressions were employed to analyze. RESULTS: Of 51,634 eligible OHCA patients, 581 (1.13%) had implanted ICDs. Among them, 53 (9.1%) patients survived to hospital discharge, and 40 (6.9%) patients had favorable neurological outcome at hospital discharge. Multivariable regression showed ICDs were not associated with OHCA outcomes in the total OHCA patients. In the OHCA patients with ICDs, shockable initial emergency medical services (EMS)-recorded rhythms and the ICD-shock-only defibrillation pattern were independent favorable factors for survival to hospital discharge(OR = 3.3, 95%CI 1.7-6.2, P < 0.001; OR = 2.4, 95%CI 1.1-5.5, P = 0.035, respectively) and neurological outcome at hospital discharge (OR = 6.5, 95%CI 2.9-14.4, P < 0.001; OR = 3.6, 95%CI 1.4-9.1, P = 0.006, respectively). During field resuscitation in OHCA patients with ICDs, at least 34.9% of total patients and 64.6% of patients with initial EMS-recorded VT/VF rhythms needed additional external shocks. CONCLUSIONS: Shockable initial EMS-recorded rhythms and ICD-shock-only defibrillation pattern were independent factors for the favorable outcomes of OHCA patients with ICDs. ICDs were not associated with the outcomes of OHCA, and additional external shocks were needed in a substantial number of OHCA patients with ICDs during field resuscitation.


Assuntos
Reanimação Cardiopulmonar , Desfibriladores Implantáveis , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Choque , Cardioversão Elétrica , Humanos , Parada Cardíaca Extra-Hospitalar/terapia
4.
Sci Rep ; 10(1): 16694, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028918

RESUMO

Reservoir quality is a critical risk factor in basement reservoirs. Researches into basement reservoirs by petrographic analysis combined with X-ray diffraction, log identification, electron microscopy, field emission scanning electron microscopy, porosity and pulse-decay permeability and core analysis have provided insights into the characterization of the commonality, diversity and difference of the weathered basement rocks as gas reservoirs in the Dongping field. Geological structures, lithology and near-surface processes control the reservoir physical property together. From Wellblock Dp 3 to Wellblock Dp 17, the high uplift gradually transforms into the low slope area towards the center of basin, with the lithology changing as well, which results in different degrees of fracture development in the bedrock in different wellblocks. The basement lithologies are granite, granitic gneiss, and limestone with slate in Wellblock Dp3, Dp1 and Dp17, respectively. Though they all provide effective reservoir space for gas accumulation, the productivity of nature gas shows significant differences. Fractures are the main store space in the three wellblocks. The development of fractures gives rise to secondary porosity around them because of physical weathering and chemical dissolution, but they generate many inhomogeneous fractures and secondary solution pores, whether on the planar distribution or in vertical. In Wellblock Dp3, high angle fractures were generated under the action of structural stress mechanism, with a large number of secondary pores. The porosity is between 0.1 and 23.2%. In Wellblock Dp 1, low angle fractures were the main storage space, with plenty of solution pores mainly in melanocratic minerals. The porosity is between 0.1 and 18.8%. In Wellblock Dp 17, where short and dense fractures developed, the porosity is between 0.1 and 10.3%. The data indicate that the granite in the uplift in Wellblock Dp3 has better reservoir properties due to the stronger physical weathering and chemical dissolution. As the porosity gradually decreases towards the slope and low-lying area, the more favorable exploration area should be the uplift and slope area in the depression area. However, the effective caprock developed locally in Wellblock Dp3, which affected the gas accumulation. Meanwhile, the reservoirs' petrophysical properties showed distintive variation with different depths in different wellblocks. High productivity layers are under the 200 m, 100 m and 200 m depths from the top of the basement rocks in Wellblock Dp 3, Wellblock Dp 1 and Wellblock Dp 17, respectively. This suggestion in this study will be of significance for guiding oil and gas exploration in front of the Altun Mountains.

5.
Cardiol Res Pract ; 2020: 3786408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32300483

RESUMO

BACKGROUND: The conversion from a nonshockable rhythm (asystole or pulseless electrical activity (PEA)) to a shockable rhythm (pulseless ventricular tachycardia or ventricular fibrillation) may be associated with better out-of-hospital cardiac arrest (OHCA) outcomes. There are insufficient data on the prognostic significance of such conversions by initial heart rhythm and different rhythm conversion time. METHODS: Among 24,849 adult OHCA patients of presumed cardiac etiology with initial asystole or PEA in the Resuscitation Outcomes Consortium Cardiac Epidemiologic Registry (version 3, 2011-2015), we examined the association of shockable rhythm conversion with prehospital return of spontaneous circulation (ROSC), survival, and favorable functional outcome (modified Rankin Scale score ≤3) at hospital discharge by initial rhythm and rhythm conversion time (time from cardiopulmonary resuscitation (CPR) initiation by emergency medical providers to first shock delivery), using logistic regression adjusting for key clinical characteristics. RESULTS: Of 16,516 patients with initial asystole and 8,333 patients with initial PEA, 16% and 20% underwent shockable rhythm conversions; the median rhythm conversion time was 12.0 (IQR: 6.7-18.7) and 13.2 (IQR: 7.0-20.5) min, respectively. No difference was found in odds of prehospital ROSC across rhythm conversion time, regardless of initial heart rhythm. Shockable rhythm conversion was associated with survival and favorable functional outcome at hospital discharge only when occurred during the first 15 min of CPR, for those with initial asystole, or the first 10 min of CPR, for those with initial PEA. The associations between shockable rhythm conversion and outcomes were stronger among those with initial asystole compared with those with initial PEA. CONCLUSIONS: The conversion from a nonshockable rhythm to a shockable rhythm was associated with better outcomes only when occurred early in initial nonshockable rhythm OHCA, and it has greater prognostic significance when the initial rhythm was asystole.

6.
Resuscitation ; 149: 209-216, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31982506

RESUMO

BACKGROUND: Adrenaline is an important component in the resuscitation of individuals experiencing out-of-hospital cardiac arrest (OHCA). The 2018 Advanced Cardiac Life Support (ACLS) algorithm gives the option of either intravenous (IV) or intraosseous (IO) routes for adrenaline administration during cardiac arrest. However, the optimal route during prehospital resuscitation remains controversial. This study aims to investigate whether IV and IO routes lead to different outcomes in OHCA patients who received prehospital adrenaline. METHODS: This retrospective analysis included adult patients with OHCA of presumed cardiac origin who had Emergency Medical Services (EMS) CPR, received adrenaline, and were enrolled in the Resuscitation Outcomes Consortium (ROC) Cardiac Epistry version 3 database between 2011 and 2015. We divided the study population into IV and IO groups based on the administration route. Logistic regression analysis was performed to evaluate the association between adrenaline delivery routes and prehospital return of spontaneous circulation (ROSC), survival to hospital discharge, and favorable neurological outcome. RESULTS: Of the 35,733 patients included, 27,758 (77.7%) had adrenaline administered via IV access and 7975 (22.3%) via IO access. With the IO group as a reference in the logistic regression model, the adjusted odds ratios of the IV group for prehospital ROSC, survival and favorable neurological outcome were 1.367 (95%CI, 1.276-1.464), 1.468 (95%CI, 1.264-1.705) and 1.849 (95%CI, 1.526-2.240), respectively. Similar results were found in the propensity score matched population and subgroup analysis. CONCLUSION: Compared with the IO approach, the IV approach appears to be the optimal route for adrenaline administration in advanced life support for OHCA during prehospital resuscitation.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Epinefrina/uso terapêutico , Humanos , Infusões Intraósseas , Parada Cardíaca Extra-Hospitalar/tratamento farmacológico , Estudos Retrospectivos
7.
Resuscitation ; 127: 68-72, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29631004

RESUMO

BACKGROUND: Signing Do-Not-Resuscitate orders is an important element contributing to a worse prognosis for out-of-hospital cardiac arrest (OHCA). However, our data showed that some of those OHCA patients with Do-Not-Resuscitate orders signed in hospital survived to hospital discharge, and even recovered with favorable neurological function. In this study, we described their clinical features and identified those factors that were associated with better outcomes. METHODS: A retrospective, observational analysis was performed on all adult non-traumatic OHCA who were enrolled in the Resuscitation Outcomes Consortium (ROC) PRIMED study but signed Do-Not-Resuscitate orders in hospital after admission. We reported their demographics, characteristics, interventions and outcomes of all enrolled cases. Patients surviving and not surviving to hospital discharge, as well as those who did and did not obtain favorable neurological recovery, were compared. Logistic regression models assessed those factors which might be prognostic to survival and favorable neurological outcomes at discharge. RESULTS: Of 2289 admitted patients with Do-Not-Resuscitate order signed in hospital, 132(5.8%) survived to hospital discharge and 28(1.2%) achieved favorable neurological recovery. Those factors, including witnessed arrest, prehospital shock delivered, Return of Spontaneous Circulation (ROSC) obtained in the field, cardiovascular interventions or procedures applied, and no prehospital adrenaline administered, were independently associated with better outcomes. CONCLUSIONS: We suggest that some factors should be taken into considerations before Do-Not-Resuscitate decisions are made in hospital for those admitted OHCA patients.


Assuntos
Reanimação Cardiopulmonar/estatística & dados numéricos , Parada Cardíaca Extra-Hospitalar/mortalidade , Ordens quanto à Conduta (Ética Médica) , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisão Clínica , Cardioversão Elétrica , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/terapia , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Análise de Sobrevida , Tempo para o Tratamento
8.
Elife ; 72018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29350614

RESUMO

Current understanding of aggressive human basal-like triple-negative breast cancer (TNBC) remains incomplete. In this study, we show endothelial lipase (LIPG) is aberrantly overexpressed in basal-like TNBCs. We demonstrate that LIPG is required for in vivo tumorigenicity and metastasis of TNBC cells. LIPG possesses a lipase-dependent function that supports cancer cell proliferation and a lipase-independent function that promotes invasiveness, stemness and basal/epithelial-mesenchymal transition features of TNBC. Mechanistically, LIPG executes its oncogenic function through its involvement in interferon-related DTX3L-ISG15 signaling, which regulates protein function and stability by ISGylation. We show that DTX3L, an E3-ubiquitin ligase, is required for maintaining LIPG protein levels in TNBC cells by inhibiting proteasome-mediated LIPG degradation. Inactivation of LIPG impairs DTX3L-ISG15 signaling, indicating the existence of DTX3L-LIPG-ISG15 signaling. We further reveal LIPG-ISG15 signaling is lipase-independent. We demonstrate that DTX3L-LIPG-ISG15 signaling is essential for malignancies of TNBC cells. Targeting this pathway provides a novel strategy for basal-like TNBC therapy.


Assuntos
Carcinogênese , Lipase/metabolismo , Metástase Neoplásica/patologia , Metástase Neoplásica/fisiopatologia , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/fisiopatologia , Movimento Celular , Proliferação de Células , Citocinas/metabolismo , Transição Epitelial-Mesenquimal , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo
9.
Resuscitation ; 121: 1-8, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28943123

RESUMO

BACKGROUND: There remains controversy over the prognostic significance of spontaneous shockable rhythm conversion in out-of-hospital cardiac arrest (OHCA) patients with initial non-shockable heart rhythms (pulseless electrical activity [PEA] or asystole). The aim of this study was to examine the association of shockable rhythm conversion with multiple OHCA outcomes, and to explore effect modifiers. METHODS: A dual-reviewer search was conducted in PubMed and EMBASE databases in March 2017. Data on study design, patient characteristics, outcomes, adjusting and stratifying variables were extracted. Estimates were combined using random-effects models. RESULTS: Twelve studies involving 1,108,281 OHCA patients with initial non-shockable heart rhythms were identified using pre-specified eligibility criteria. Combined adjusted estimates showed that shockable rhythm conversion was associated with higher odds of pre-hospital return of spontaneous circulation (ROSC) (odds ratio [OR]=1.47, 95% confidence interval [CI] 1.40-1.55). Although shockable rhythm conversion was not associated with survival to hospital discharge (OR=1.36, 95% CI 0.77-2.38), it was associated with higher odds of one-month survival (OR=1.96, 95% CI 1.66-2.31), and one-month favourable neurological outcome (OR=2.69, 95% CI 2.00-3.62). Subgroup analyses found that shockable rhythm conversion from asystole, but not PEA, was associated with pre-hospital ROSC and survival to hospital discharge, and that earlier shockable rhythm conversions, compared to those occurring later during cardiopulmonary resuscitation, were associated with higher odds of one-month favourable neurological outcome. CONCLUSION: Shockable rhythm conversion from initial non-shockable heart rhythms was associated with better OHCA outcomes, depending on the type of initial heart rhythm, and time of rhythm conversion.


Assuntos
Reanimação Cardiopulmonar/mortalidade , Cardioversão Elétrica/mortalidade , Parada Cardíaca Extra-Hospitalar/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Reanimação Cardiopulmonar/métodos , Serviços Médicos de Emergência , Feminino , Frequência Cardíaca , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prognóstico , Estudos Prospectivos , Fatores de Tempo
10.
J Biol Chem ; 292(27): 11466-11484, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28512126

RESUMO

The normal myoepithelium has a tumor-suppressing nature and inhibits the progression of ductal carcinoma in situ (DCIS) into invasive ductal carcinoma (IDC). Conversely, a growing number of studies have shown that tumor-associated myoepithelial cells have a tumor-promoting effect. Moreover, the exact role of tumor-associated myoepithelial cells in the DCIS-to-IDC development remains undefined. To address this, we explored the role of tumor-associated myoepithelial cells in the DCIS-to-IDC progression. We developed a direct coculture system to study the cell-cell interactions between DCIS cells and tumor-associated myoepithelial cells. Coculture studies indicated that tumor-associated myoepithelial cells promoted the invasive progression of a DCIS cell model in vitro, and mechanistic studies revealed that the interaction with DCIS cells stimulated tumor-associated myoepithelial cells to secrete TGFß1, which subsequently contributed to activating the TGFß/Smads pathway in DCIS cells. We noted that activation of the TGFß signaling pathway promoted the epithelial-mesenchymal transition, basal-like phenotypes, stemness, and invasiveness of DCIS cells. Importantly, xenograft studies further demonstrated that tumor-associated myoepithelial cells enhanced the DCIS-to-IDC progression in vivo Furthermore, we found that TGFß-mediated induction of oncogenic miR-10b-5p expression and down-regulation of RB1CC1, a miR-10b-5p-targeted tumor-suppressor gene, contributed to the invasive progression of DCIS. Our findings provide the first experimental evidence to directly support the paradigm that altered DCIS-associated myoepithelial cells promote the invasive progression of DCIS into IDC via TGFß signaling activation.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Células Epiteliais/metabolismo , Células Mieloides/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Linhagem Celular Tumoral , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Células Mieloides/patologia , Invasividade Neoplásica , Transplante de Neoplasias , RNA Neoplásico/metabolismo
11.
Mol Cell Biol ; 37(4)2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27895151

RESUMO

Human breast adipose tissue is a heterogeneous cell population consisting of mature white adipocytes, multipotent mesenchymal stem cells, committed progenitor cells, fibroblasts, endothelial cells, and immune cells. Dependent on external stimulation, adipose-derived stem cells differentiate along diverse lineages into adipocytes, chondrocytes, osteoblasts, fibroblasts, and myofibroblasts. It is currently not fully understood how a high-fat diet reprograms adipose-derived stem cells into myofibroblasts. In our study, we used mouse models of a regular diet and of high-fat-diet-induced obesity to investigate the role of dietary fat on myofibroblast differentiation in the mammary stromal microenvironment. We found that a high-fat diet promotes myofibroblast differentiation by decreasing microRNA 140 (miR-140) expression in mammary adipose tissue through a novel negative-feedback loop. Increased transforming growth factor ß1 (TGF-ß1) in mammary adipose tissue in obese mice activates SMAD3 signaling, causing phospho-SMAD3 to bind to the miR-140 locus and inhibit miR-140 transcription. This prevents miR-140 from targeting SMAD3 for degradation, resulting in amplified TGF-ß1/SMAD3 signaling and miR-140 downregulation-dependent myofibroblast differentiation. Using tissue and coculture models, we found that myofibroblasts and the fibrotic microenvironment created by myofibroblasts impact the stemness and proliferation of normal ductal epithelial cells and early-stage breast cancer invasion and stemness.


Assuntos
Dieta Hiperlipídica , Regulação para Baixo/genética , Glândulas Mamárias Animais/patologia , MicroRNAs/genética , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Animais , Diferenciação Celular/genética , Separação Celular , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Retroalimentação Fisiológica , Feminino , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , Transdução de Sinais , Células Estromais/citologia , Células Estromais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
12.
Sci Rep ; 6: 39572, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27996039

RESUMO

Radiation-induced lung fibrosis (RILF) is a common side effect for patients with thoracic cancer receiving radiation therapy. RILF is characterized by excessive collagen deposition mediated by TGF-ß1 and its downstream factor SMAD3, but the exact molecular mechanism leading to fibrosis is yet to be determined. The present study investigated the impact of miR-140 on RILF development. Herein, we first found that loss of miR-140 is a marker of fibrotic lung tissue in vivo one-year post-radiation treatment. We showed that miR-140 knockout primary lung fibroblasts have a higher percentage of myofibroblasts compared to wild type primary lung fibroblasts, and that loss of miR-140 expression leads to increased activation of TGF-ß1 signaling as well as increased myofibroblast differentiation. We also identified fibronectin as a novel miR-140 target gene in lung fibroblasts. Finally, we have shown that miR-140 deficiency promotes accumulation of M2 macrophages in irradiated lung tissues. These data suggest that miR-140 is a key protective molecule against RILF through inhibiting myofibroblast differentiation and inflammation.


Assuntos
Reprogramação Celular , Fibroblastos/citologia , Pulmão/patologia , Macrófagos/citologia , MicroRNAs/metabolismo , Lesões por Radiação/metabolismo , Animais , Separação Celular , Colágeno/química , Fibronectinas/metabolismo , Citometria de Fluxo , Células HEK293 , Humanos , Inflamação , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/metabolismo , Fibrose Pulmonar/patologia , Fatores de Risco , Transdução de Sinais , Proteína Smad3/metabolismo
13.
Oncotarget ; 7(40): 65067-65089, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27556296

RESUMO

Dysregulation of long non-codng RNA (lncRNA) expression has been found to contribute to tumorigenesis. However, the roles of lncRNAs in BRCA1-related breast cancer remain largely unknown. In this study, we delineate the role of the novel BRCA1/lncRNA NEAT1 signaling axis in breast tumorigenesis. BRCA1 inhibits NEAT1 expression potentially through binding to its genomic binding site upstream of the NEAT1 gene. BRCA1 deficiency in human normal/cancerous breast cells and mouse mammary glands leads to NEAT1 overexpression. Our studies show that NEAT1 upregulation resulting from BRCA1 deficiency stimulates in vitro and in vivo breast tumorigenicity. We have further identified molecular mediators downstream of the BRCA1/NEAT1 axis. NEAT1 epigenetically silences miR-129-5p expression by promoting the DNA methylation of the CpG island in the miR-129 gene. Silencing of miR-129-5p expression by NEAT1 results in upregulation of WNT4 expression, a target of miR-129-5p, which leads to activation of oncogenic WNT signaling. Our functional studies indicate that this NEAT1/miR-129-5p/WNT4 axis contributes to the tumorigenic effects of BRCA1 deficiency. Finally our in silico expression correlation analysis suggests the existence of the BRCA1/NEAT1/miR-129-5p axis in breast cancer. Our findings, taken together, suggest that the dysregulation of the BRCA1/NEAT1/miR-129-5p/WNT4 signaling axis is involved in promoting breast tumorigenesis.


Assuntos
Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Transformação Celular Neoplásica/genética , RNA Longo não Codificante/genética , Transdução de Sinais/fisiologia , Animais , Proteína BRCA1/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Transformação Celular Neoplásica/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Proteína Wnt4/genética , Proteína Wnt4/metabolismo
14.
Oncotarget ; 7(30): 47511-47525, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27374087

RESUMO

The molecular mechanisms responsible for the Ductal Carcinoma in Situ (DCIS)-Invasive Ductal Carcinoma (IDC) transition have yet to be elucidated. Due to the lack of molecularly targeted therapies, basal-like DCIS has a high risk of recurrence and progression to invasive and metastatic cancers. In this study, by applying a novel single-cell clonogenic approach with the CD49f+/CD44+/CD24- surface markers, we characterized the aggressive clones that have enhanced self-renewal, migratory and invasive capacities derived from a human DCIS model cell line MCF10DCIS. The aggressive clones had elevated ALDH1 activity, lower global DNA methylation and increased expression of stem cell related genes, especially concurrent activation of SOX2/OCT4. In addition, we showed that the aggressive clones have increased expression of lincRNA-RoR and miR-10b compared to non-aggressive clones, which enhance their self-renewal and invasive abilities. Finally, we confirmed our in vitro results in vivo, demonstrating that aggressive clones were capable of forming tumors in nude mice, whereas non-aggressive clones were not. Our data suggest that lincRNA-RoR and miR10b could be used to distinguish aggressive clones from non-aggressive clones within the heterogeneous CD49f+/CD44+/CD24- DCIS population. Our findings also provide the foundation to develop new chemoprevention agents for DCIS-IDC transition.


Assuntos
Neoplasias da Mama/patologia , Antígeno CD24/análise , Carcinoma Intraductal não Infiltrante/patologia , Receptores de Hialuronatos/análise , Integrina alfa6/análise , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias da Mama/etiologia , Linhagem Celular Tumoral , Movimento Celular , Metilação de DNA , Feminino , Humanos , Camundongos , Fator 3 de Transcrição de Octâmero/fisiologia , Fatores de Transcrição SOXB1/fisiologia
15.
Mol Cell Biol ; 36(1): 30-8, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26459763

RESUMO

More than 40% of the U.S. population are clinically obese and suffer from metabolic syndrome with an increased risk of postmenopausal estrogen receptor-positive breast cancer. Adipocytes are the primary component of adipose tissue and are formed through adipogenesis from precursor mesenchymal stem cells. While the major molecular pathways of adipogenesis are understood, little is known about the noncoding RNA signaling networks involved in adipogenesis. Using adipocyte-derived stem cells (ADSCs) isolated from wild-type and microRNA 140 (miR-140) knockout mice, we identify a novel miR-140/long noncoding RNA (lncRNA) NEAT1 signaling network necessary for adipogenesis. miR-140 knockout ADSCs have dramatically decreased adipogenic capabilities associated with downregulation of NEAT1 expression. We identified a miR-140 binding site in NEAT1 and found that mature miR-140 in the nucleus can physically interact with NEAT1, leading to increased NEAT1 expression. We demonstrated that reexpression of NEAT1 in miR-140 knockout ADSCs is sufficient to restore their ability to undergo differentiation. Our results reveal an exciting new noncoding RNA signaling network that regulates adipogenesis and that is a potential new target in the prevention or treatment of obesity.


Assuntos
Adipócitos/metabolismo , Adipogenia/genética , MicroRNAs/genética , RNA Longo não Codificante/metabolismo , Tecido Adiposo/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Camundongos , RNA Longo não Codificante/genética , Células-Tronco/citologia , Regulação para Cima
16.
Cancer Lett ; 369(1): 184-91, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26300493

RESUMO

Breast and lung cancer patients who are treated with radiotherapy often have severe side effects, including radiation-induced lung damage and secondary cancers. Activation of the NRF2 pathway is a well-known mechanism that protects cells against radiation induced oxidative stress, but its role in radiation-induced lung damage is not well understood. Using human lung fibroblasts (HLFs) we found that ionizing radiation (IR) leads to BRCA1-dependent activation of NRF2 through the inhibition of KEAP1 function, promoting the nuclear accumulation of NRF2, and activating critical radioprotective mechanisms. We discovered that NRF2 directly binds to the miR-140 promoter and increases its expression in response to IR treatment. Gain and loss of function studies further showed the ability of miR-140 to regulate lung fibroblast self-renewal upon irradiation, a potential mechanism to contribute to the regulation of DNA repair. We verified our in vitro findings using primary lung fibroblast cultures from wild type and Nrf2 (KO) mice. Using these models we showed that IR induces overexpression of Brca1, Nrf2 and miR-140 in lung tissue after irradiation. These data reveal a novel radioprotective mechanism in which IR promotes NRF2 nuclear translocation and subsequent activation of miR-140 transcription in HLFs.


Assuntos
Fibroblastos/fisiologia , MicroRNAs/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Proteína BRCA1/metabolismo , Linhagem Celular , Autorrenovação Celular , Fibroblastos/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas , Ligação Proteica , Tolerância a Radiação
17.
Breast Cancer Res Treat ; 150(3): 685-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25783182

RESUMO

The tumor microenvironment plays a critical role in regulating breast tumor progression. Signaling between preadipocytes and breast cancer cells has been found to promote breast tumor formation and metastasis. Exosomes secreted from preadipocytes are important components of the cancer stem cell niche. Mouse preadipocytes (3T3L1) are treated with the natural antitumor compound shikonin (SK) and exosomes derived from mouse preadipocytes are co-cultured with MCF10DCIS cells. We examine how preadipocyte-derived exosomes can regulate early-stage breast cancer via regulating stem cell renewal, cell migration, and tumor formation. We identify a critical miR-140/SOX2/SOX9 axis that regulates differentiation, stemness, and migration in the tumor microenvironment. Next, we find that the natural antitumor compound SK can inhibit preadipocyte signaling inhibiting nearby ductal carcinoma in situ (DCIS) cells. Through co-culture experiments, we find that SK-treated preadipocytes secrete exosomes with high levels of miR-140, which can impact nearby DCIS cells through targeting SOX9 signaling. Finally, we find that preadipocyte-derived exosomes promote tumorigenesis in vivo, providing strong support for the importance of exosomal signaling in the tumor microenvironment. Our data also show that targeting the tumor microenvironment may assist in blocking tumor progression.


Assuntos
Adipócitos/fisiologia , Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Exossomos/fisiologia , Naftoquinonas/farmacologia , Células-Tronco Neoplásicas/patologia , Células 3T3 , Adipócitos/efeitos dos fármacos , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Cocultura , Exossomos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , MicroRNAs/genética , Transplante de Neoplasias , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Fatores de Transcrição SOX9/genética , Transdução de Sinais/efeitos dos fármacos
18.
Mol Cancer Res ; 13(2): 330-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25253741

RESUMO

UNLABELLED: Triple-negative (ER(-), HER2(-), PR(-)) breast cancer (TNBC) is an aggressive disease with a poor prognosis with no available molecularly targeted therapy. Silencing of microRNA-145 (miR-145) may be a defining marker of TNBC based on molecular profiling and deep sequencing. Therefore, the molecular mechanism behind miR-145 downregulation in TNBC was examined. Overexpression of the long intergenic noncoding RNA regulator of reprogramming, lincRNA-RoR, functions as a competitive endogenous RNA sponge in TNBC. Interestingly, lincRNA-RoR is dramatically upregulated in TNBC and in metastatic disease and knockdown restores miR-145 expression. Previous reports suggest that miR-145 has growth-suppressive activity in some breast cancers; however, these data in TNBC indicate that miR-145 does not affect proliferation or apoptosis but instead, miR-145 regulates tumor cell invasion. Investigation of miR-145-regulated pathways involved in tumor invasion revealed a novel target, the small GTPase ADP-ribosylation factor 6 (Arf6). Subsequent analysis demonstrated that ARF6, a known regulator of breast tumor cell invasion, is dramatically upregulated in TNBC and in breast tumor metastasis. Mechanistically, ARF6 regulates E-cadherin localization and affects cell-cell adhesion. These results reveal a lincRNA-RoR/miR-145/ARF6 pathway that regulates invasion in TNBCs. IMPLICATIONS: The lincRNA-RoR/miR-145/ARF6 pathway is critical to TNBC metastasis and could serve as biomarkers or therapeutic targets for improving survival.


Assuntos
Fatores de Ribosilação do ADP/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Fator 6 de Ribosilação do ADP , Fatores de Ribosilação do ADP/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Células HEK293 , Humanos , Células MCF-7 , MicroRNAs/metabolismo , Invasividade Neoplásica , RNA Longo não Codificante/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo
19.
Methods Mol Biol ; 1204: 35-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25182759

RESUMO

We have designed a dual-color fluorescent reporter that can track microRNA expression in vitro, which can be used for lineage tracing experiments. We have used this system to track miR-140 promoter activity in breast cancer cells and to follow the impact of estrogen signaling in cancer stem cell subpopulations.


Assuntos
Neoplasias da Mama/genética , Estrogênios/metabolismo , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Regiões Promotoras Genéticas , Neoplasias da Mama/metabolismo , Clonagem Molecular/métodos , Feminino , Corantes Fluorescentes/análise , Corantes Fluorescentes/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Células MCF-7 , Microscopia de Fluorescência/métodos , Plasmídeos/genética , Transdução de Sinais , Transfecção/métodos
20.
J Biol Chem ; 289(45): 31310-8, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25231996

RESUMO

Long noncoding RNAs (lncRNAs) have emerged as key regulators of gene expression in embryonic stem cell (ESC) self-renewal and differentiation. In ESCs, lncRNAs are regulated at the genetic level via transcription factor binding to lncRNA gene promoters. Here we demonstrate that the key cytoprotective transcription factor NRF2 controls lncRNA expression in mammary stem cells. By profiling lncRNAs in wild-type and NRF2 knockdown mammary stem cells, we demonstrate that the lncRNA ROR, a regulator of embryonic stem cell pluripotency, is overexpressed upon NRF2 knockdown. We performed promoter analyses and examined predicted NRF2 binding elements in the ROR promoter using luciferase reporter constructs of a ROR promoter deletion series. Our studies revealed that NRF2 binds to two specific NRF2 response elements flanking the ROR promoter and that these two NRF2 response elements are equally important to suppress ROR transcription. In addition, we identified associated H3K27me3 chromatin modification and EZH2 binding at the ROR promoter that was dependent on NRF2 binding. We observed that NRF2 knockdown or ROR overexpression leads to increased stem cell self-renewal in mammary stem cells. Furthermore, we demonstrate Nrf2 regulation of the mammary stem cell population in vivo. These observations provide further evidence for the critical role of NRF2 in maintaining normal stem cell subpopulations in mammary epithelium.


Assuntos
Estrogênios/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator 2 Relacionado a NF-E2/metabolismo , RNA Longo não Codificante , Células-Tronco/citologia , Animais , Antioxidantes/química , Linhagem Celular Tumoral , Células-Tronco Embrionárias/citologia , Células Epiteliais/citologia , Feminino , Hematopoese , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Regiões Promotoras Genéticas , Ligação Proteica , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Transdução de Sinais
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