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Histone deacetylase 6 (HDAC6) mediates DNA damage signaling by regulating the mismatch repair and nucleotide excision repair pathways. Whether HDAC6 also mediates DNA double-strand break (DSB) repair is unclear. Here, we report that HDAC6 negatively regulates DSB repair in an enzyme activity-independent manner. In unstressed cells, HDAC6 interacts with H2A/H2A.X to prevent its interaction with the E3 ligase RNF168. Upon sensing DSBs, RNF168 rapidly ubiquitinates HDAC6 at lysine 116, leading to HDAC6 proteasomal degradation and a restored interaction between RNF168 and H2A/H2A.X. H2A/H2A.X is ubiquitinated by RNF168, precipitating the recruitment of DSB repair factors (including 53BP1 and BRCA1) to chromatin and subsequent DNA repair. These findings reveal novel regulatory machinery based on an HDAC6-RNF168 axis that regulates the H2A/H2A.X ubiquitination status. Interfering with this axis might be leveraged to disrupt a key mechanism of cancer cell resistance to genotoxic damage and form a potential therapeutic strategy for cancer.
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Reparación del ADN , Humanos , Línea Celular Tumoral , Daño del ADN , Histona Desacetilasa 6/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , UbiquitinaciónRESUMEN
The fundamental role of cells in safeguarding the genome's integrity against DNA double-strand breaks (DSBs) is crucial for maintaining chromatin homeostasis and the overall genomic stability. Aberrant responses to DNA damage, known as DNA damage responses (DDRs), can result in genomic instability and contribute significantly to tumorigenesis. Unraveling the intricate mechanisms underlying DDRs following severe damage holds the key to identify therapeutic targets for cancer. Chromatin lysine acylation, encompassing diverse modifications such as acetylation, lactylation, crotonylation, succinylation, malonylation, glutarylation, propionylation, and butyrylation, has been extensively studied in the context of DDRs and chromatin homeostasis. Here, we delve into the modifying enzymes and the pivotal roles of lysine acylation and their crosstalk in maintaining chromatin homeostasis and genome integrity in response to DDRs. Moreover, we offer a comprehensive perspective and overview of the latest insights, driven primarily by chromatin acylation modification and associated regulators.
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Attempts to create quantum degenerate gases without evaporative cooling have been pursued since the early days of laser cooling, with the consensus that polarization gradient cooling (PGC, also known as "optical molasses") alone cannot reach condensation. In the present work, we report that simple PGC can generate a small Bose-Einstein condensate (BEC) inside a corrugated micrometer-sized optical dipole trap. The experimental parameters enabling BEC creation were found by machine learning, which increased the atom number by a factor of 5 and decreased the temperature by a factor of 2.5, corresponding to almost 2 orders of magnitude gain in phase space density. When the trapping light is slightly misaligned through a microscopic objective lens, a BEC of â¼250 ^{87}Rb atoms is formed inside a local dimple within 40 ms of PGC after MOT loading.
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BACKGROUND: Psoriasis is a common chronic inflammatory disease with an unclear aetiology. Keratinocytes in psoriasis are susceptible to exogenous triggers that induce inflammatory cell death. OBJECTIVES: To investigate whether gasdermin E (GSDME)-mediated pyroptosis in keratinocytes contributes to the pathogenesis of psoriasis. METHODS: Skin samples from patients with psoriasis and from healthy controls were collected to evaluate the expression of GSDME, cleaved caspase-3 and inflammatory factors. We then analysed the data series GSE41662 to further compare the expression of GSDME between lesional and nonlesional skin samples in those with psoriasis. In vivo, a caspase-3 inhibitor and GSDME-deficient mice (Gsdme-/-) were used to block caspase-3/GSDME activation in an imiquimod-induced psoriasis model. Skin inflammation, disease severity and pyroptosis-related proteins were analysed. In vitro, tumour necrosis factor (TNF)-α-induced caspase-3/GSDME-mediated pyroptosis in the HACAT cell line was explored. RESULTS: Our analysis of the GSE41662 data series found that GSDME was upregulated in psoriasis lesions vs. normal skin. High levels of inflammatory cytokines such as interleukin (IL)-1ß, IL-6 and TNF-α were also found in psoriasis lesions. In mice in the Gsdme-/- and caspase-3 inhibitor groups, the severity of skin inflammation was attenuated and GSDME and cleaved caspase-3 levels decreased after imiquimod treatment. Similarly, IL-1ß, IL-6 and TNF-α expression was decreased in the Gsdme-/- and caspase-3 inhibitor groups. In vitro, TNF-α induced HACAT cell pyroptosis through caspase-3/GSDME pathway activation, which was suppressed by blocking caspase-3 or silencing Gsdme. CONCLUSIONS: Our study provides a novel explanation of TNF-α/caspase-3/GSDME-mediated keratinocyte pyroptosis in the initiation and -acceleration of skin inflammation and the progression of psoriasis.
Psoriasis is chronic and autoinflammatory common skin disease that affects 23% of the world's population. The disease is characterized by persistent inflammation in various body systems, including the skin and joints. However, the exact cause of the disease is unclear. In this study from China, we found that in people with psoriasis a protein called 'gasdermin E' (or 'GSDME') is increased in a type of skin cell called keratinocytes. In psoriasis, these keratinocytes are susceptible to a type of cell death called 'pyroptosis'. We aimed to find out whether pyroptosis caused by GSDME in keratinocytes contributes to the development of psoriasis. To do this, we looked at samples of skin from people with psoriasis and compared these to samples from healthy controls (those without psoriasis). Firstly, we investigated the levels of GSDME, another protein called caspase-3 and other inflammatory factors in the skin lesions from patients with psoriasis. Secondly, we analysed previously published data from 24 patients with psoriasis. Finally, we carried out a range of experiments to confirm our findings. We found that keratinocyte pyroptosis was mediated by the messenger proteins TNF-α/caspase-3, and that GSDME played a key role in the initiation and acceleration of skin inflammation and the progression of psoriasis. Targeting the GSDME pathway may be a novel strategy in treating psoriasis.
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Imiquimod , Queratinocitos , Psoriasis , Piroptosis , Piroptosis/fisiología , Psoriasis/patología , Psoriasis/metabolismo , Psoriasis/inmunología , Humanos , Queratinocitos/metabolismo , Animales , Ratones , Ratones Noqueados , Piel/patología , Piel/metabolismo , Piel/inmunología , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Células HaCaT , Masculino , Femenino , Proteínas de Unión a Fosfato/metabolismo , Estudios de Casos y Controles , Regulación hacia Arriba , Factor de Necrosis Tumoral alfa/metabolismo , GasderminasRESUMEN
This paper studies how negative emotions like stress, anxiety, and boredom can affect unhealthy food consumption. Using the Wuhan lockdown as an external shock, we examine the changes in food consumption in a city that was not in lockdown. We applied the difference-in-differences method to a large scanner dataset from a retail monopoly in China. Our findings reveal that negative emotions induced by the pandemic lockdown significantly elevated consumer spending on unhealthy food items such as crisps, sugary beverages, regular soda, and low-alcohol beverages. Notably, the effect of unhealthy food consumption was more pronounced among younger and wealthier demographics. Triggering factors, like information about confirmed new deaths and infections as well as proximity to local hospitals, were found to strongly influence the consumption of unhealthy foods. Overall, the lockdown's impact extended beyond short-term increases in snack consumption to substantial increases in overall dietary and nutritional intake.
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COVID-19 , Humanos , Control de Enfermedades Transmisibles , Bebidas , Bebidas Gaseosas , EmocionesRESUMEN
Epidemiologic surveys have indicated that cigarette smoking is an important risk factor for diabetes, but its mechanisms remain unclear. Andrographolide, an herb traditionally utilized in medicine, provides anti-inflammatory benefits for various diseases. In the present work, 265 patients with Type 2 diabetes (T2D) were investigated, and male C57BL/6 mice were exposed to cigareete smoke (CS) and/or to intraperitoneally injected andrographolide for 3 months. To elucidate the mechanism of CS-induced hyperglycemia and the protective mechanism of andrographolide, MIN6 cells were exposed to cigarette smoke extract (CSE) and/or to andrographolide. Our data from 265 patients with T2D showed that urinary creatinine and serum inflammatory cytokines (interleukin 6 (IL-6), IL-8, IL-1ß, and tumor necrosis factor α (TNF-α)) increased with smoking pack-years. In a mouse model, CS induced hyperglycemia, decreased insulin secretion, and elevated inflammation and pyroptosis in ß-cells of mice. Treatment of mice with andrographolide preserved pancreatic function by reducing the expression of inflammatory cytokines; the expression of TXNIP, NLRP3, cleaved caspase 1, IL-1ß; and the N-terminal of gasdermin D (GSDMD) protein. For MIN6 cells, CSE caused increasing secretion of the inflammatory cytokines IL-6 and IL-1ß, and the expression of TXNIP and pyroptosis-related proteins; however, andrographolide alleviated these changes. Furthermore, silencing of TXNIP showed that the blocking effect of andrographolide may be mediated by TXNIP. In sum, our results indicate that CS induces hyperglycemia through TXNIP-NLRP3-GSDMD axis-mediated inflammation and pyroptosis of islet ß-cells and that andrographolide is a potential therapeutic agent for CS-induced hyperglycemia.
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Fumar Cigarrillos , Diabetes Mellitus Tipo 2 , Diterpenos , Hiperglucemia , Proteínas de Unión a Fosfato , Humanos , Masculino , Ratones , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Piroptosis , Interleucina-6/metabolismo , Ratones Endogámicos C57BL , Inflamación/metabolismo , Citocinas/metabolismo , Proteínas Portadoras , Gasderminas , Productos de TabacoRESUMEN
Obesity and overweight are independent risk factors of erectile dysfunction (ED). It is controversial whether weight loss can improve erectile function. We thereby performed this meta-analysis to clarify the therapeutic effect of weight loss on erectile function in overweight or obese men. Literature search was conducted on databases including Cochrane Library, Embase, Web of Science and PubMed to obtain all relevant English articles published before March 1, 2021. The primary outcome was final International Index of Erectile Function (IIEF) score or change in IIEF score. The secondary outcome was final body weight and body mass index (BMI) or change in body weight and BMI. After screening, 5 studies with 619 participants were enrolled in our meta-analysis. Our result showed that the mean difference in body weight between weight loss group and control group was -18.07 kg with p < .01, and the mean difference in BMI was -9.6 kg/m2 with p < .01. The mean difference of IIEF between weight loss group and control group was 1.99 with p < .01. This meta-analysis showed that weight loss could improve erectile function in overweight or obese men. Losing weight could serve as an adjuvant therapy for ED.
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Disfunción Eréctil , Sobrepeso , Disfunción Eréctil/etiología , Humanos , Masculino , Obesidad/complicaciones , Sobrepeso/complicaciones , Erección Peniana , Ensayos Clínicos Controlados Aleatorios como Asunto , Pérdida de PesoRESUMEN
Idiopathic hypogonadotropic hypogonadism (IHH) is a rare genetically heterogeneous disease and characterized by incomplete or absent puberty and infertility. It is worth noting that partial IHH patients could recover reproductive endocrine function following treatment, which is termed reversal. This study aimed to investigate clinical and genetic characteristics of IHH reversal patients. A total of 141 IHH male patients were enrolled and followed up regularly. Their clinical and genetic features were collected and analysed to discover something in common in reversal cases. These IHH patients with a median age of 21 years (interquartile range: 18-24) were divided into reversal group (n = 13) and non-reversal group (n = 128). IL17RD, ERBB4, DLX5, EGFR, SEMA4D, B3GNT1 and CCKAR RSVs were demonstrated in reversal cases for the first time. Pathogenic/likely pathogenic (P/LP) RSVs consisted of 3 RSVs (one each patient, including PROKR2 p.W178S, EGFR p.G630R and CCKAR p.S291del) in reversal group. Reversal of IHH could not be ignored in clinical follow-up. Patients with high levels of basal LH and T may harbour more possibility of reversal and worthy extra attention to identify whether reversal occurs or not. Relapse after reversal also needs to be monitored.
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Hipogonadismo , Adulto , Humanos , Masculino , Adulto Joven , China , Estudios de Cohortes , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/genéticaRESUMEN
We demonstrate a new approach for fast preparation, manipulation, and collective readout of an atomic Rydberg-state qubit. By making use of Rydberg blockade inside a small atomic ensemble, we prepare a single qubit within 3 µs with a success probability of F_{p}=0.93±0.02, rotate it, and read out its state in 6 µs with a single-shot fidelity of F_{d}=0.92±0.04. The ensemble-assisted detection is 10^{3} times faster than imaging of a single atom with the same optical resolution, and enables fast repeated nondestructive measurement. We observe qubit coherence times of 15 µs, much longer than the π rotation time of 90 ns. Potential applications ranging from faster quantum information processing in atom arrays to efficient implementation of quantum error correction are discussed.
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N6-methyladenosine (m6A) is the most prevalent internal modification present in the mRNAs of all higher eukaryotes, where it is present within both coding and noncoding regions. In mammals, methylation requires the catalysis of a multicomponent m6A methyltransferase complex. Proposed biological functions for m6A modification include pre-mRNA splicing, RNA stability, cell fate regulation, and embryonic development. However, few studies have been conducted on m6A modification in trees. In particular, the regulation mechanism of RNA m6A in Populus development remains to be further elucidated. Here, we show that PtrMTA (Populus trichocarpa methyltransferase) was colocalized with PtrFIP37 in the nucleus. Importantly, the PtrMTA-overexpressing plants significantly increased the density of trichomes and exhibited a more developed root system than that of wild-type controls. Moreover, we found that PtrMTA-overexpressing plants had better tolerance to drought stress. We also found PtrMTA was a component of the m6A methyltransferase complex, which participated in the formation of m6A methylation in poplar. Taken together, these results demonstrate that PtrMTA is involved in drought resistance by affecting the development of trichomes and roots, which will provide new clues for the study of RNA m6A modification and expand our understanding of the epigenetic molecular mechanism in woody plants.
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Adaptación Biológica , Sequías , Metiltransferasas/genética , Desarrollo de la Planta , Raíces de Plantas/fisiología , Populus/fisiología , ARN Mensajero/genética , Tricomas/genética , Regulación de la Expresión Génica de las Plantas , Inmunohistoquímica , Metiltransferasas/metabolismo , Fenotipo , Desarrollo de la Planta/genética , Fenómenos Fisiológicos de las Plantas , ARN Mensajero/metabolismo , Estrés Fisiológico , Tricomas/metabolismoRESUMEN
BACKGROUND The WD repeat domain 5 (WDR5) is an essential component of methyltransferase complexes. The expression of WDR5 has been reported in several types of malignancy. This study aimed to investigate the expression of the WDR5 gene and protein in a human papillary carcinoma cell line in vitro, including the use WDR5 gene silencing, and the expression of the WDR5 protein in papillary thyroid carcinoma tissue, and clinicopathological characteristics including overall survival (OS). MATERIAL AND METHODS The role of WDR5 in proliferation and migration of the human papillary thyroid carcinoma cell line, KTC-1, was investigated using the cell counting kit-8 (CCK-8) assay and transwell assay after silencing WDR5 expression. Expression levels of WDR5 in 84 patients with papillary thyroid carcinoma were detected using immunohistochemistry. The correlation between WDR5 expression and clinicopathological features was analyzed using the chi-squared test. The prognostic role of WDR5 was evaluated by univariate analysis with the log-rank test, and by multivariate analysis with the Cox regression model. RESULTS WDR5 expression promoted the proliferation and migration of the KTC-1 cells. In tumor tissue from patients with papillary thyroid carcinoma, low expression and high expression levels of WDR5 were found in 72.6% and 27.4%, respectively. Increased expression of WDR5 was significantly associated with lymphatic invasion and reduced survival rates. WDR5 expression was an independent negative prognostic biomarker. CONCLUSIONS Expression of WDR5 promoted cell proliferation and migration in vitro and was associated with reduced prognosis in patients with papillary thyroid carcinoma.
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N-Metiltransferasa de Histona-Lisina/genética , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Adulto , Anciano , Pueblo Asiatico/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Progresión de la Enfermedad , Femenino , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Cáncer Papilar Tiroideo/metabolismo , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patologíaRESUMEN
BACKGROUND SET and MYND domain-containing protein 2 (SMYD2), which is identified as a protein-lysine methyltransferase, plays a crucial role in the progression of some tumors such as bladder carcinoma. However, the clinical significance of SMYD2 in patients with papillary thyroid carcinoma (PTC) has not been elucidated. In the present study, we aimed to investigate the expression and role of SMYD2 in human PTC. MATERIAL AND METHODS Clinicopathological analysis was performed in 107 patients with PTC. Expression of SMYD2 was determined by immunohistochemistry staining, quantitative RT-PCR, or Western blotting in PTC tissues, adjacent normal tissues, and PTC cells (K1 and B-CPAP). The prognostic value of SMYD2 in PTC patients was assessed by univariate and multivariate analysis. Clinical outcomes were evaluated by Kaplan-Meier log-rank tests. Cell proliferation was examined in PTC cells following overexpression or knockdown of SMYD2. RESULTS SMYD2 was highly expressed in PTC tissues compared to adjacent thyroid tissues. Additionally, high expression of SMYD2 was significantly related to tumor size, lymph node metastasis, and TNM stage. Moreover, SMYD2 was identified as an independent prognosis factor by multivariate analysis. Using 2 PTC cell lines, K1 and B-CPAP, we demonstrated that high expression of SMYD2 can promote tumor cell proliferation. CONCLUSIONS SMYD2 expression was upregulated in PTC tissues and significantly related to the poorer prognosis of PTC patients. Our studies suggested the potential role of SMYD2 as a new therapeutic target and prognostic biomarker in human PTC.
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N-Metiltransferasa de Histona-Lisina/biosíntesis , Cáncer Papilar Tiroideo/enzimología , Adulto , Anciano , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular/fisiología , Progresión de la Enfermedad , Femenino , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Cáncer Papilar Tiroideo/genética , Transcriptoma , Regulación hacia ArribaRESUMEN
The goal of diabetic drug treatment is to stabilize the blood sugar for a long time to close to the normal level, to correct the metabolic disorder and eliminate the symptoms. At present, glimepiride has become commonly used drugs for the treatment of diabetes with obesity. Compared with metformin, acarbose and rosiglitazone, glimepiride has different mechanisms of drug action, clinical combination showed synergistic hypoglycemic effect, good clinical curative effect. So, we use three treatments to study as group A (glimepiride and metformin); group B (glimepiride and acarbose); Group C (glimepiride and rosiglitazone). From the analysis of drug economics, glimepiride and metformin scheme is better, has the lowest cost per unit cost effect. From the comparison of scheme is efficient, the best curative effect is rosiglitazone plus glimepiride, effective rate as 96.7%. At the same time, the drug can be rationally used to reduce the occurrence of some drug-induced diseases and adverse drug reactions.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Economía Farmacéutica , Compuestos de Sulfonilurea/administración & dosificación , Compuestos de Sulfonilurea/uso terapéutico , Acarbosa/administración & dosificación , Acarbosa/economía , Acarbosa/uso terapéutico , Adulto , Glucemia , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/economía , Hipoglucemiantes/uso terapéutico , Masculino , Metformina/administración & dosificación , Metformina/economía , Metformina/uso terapéutico , Persona de Mediana Edad , Rosiglitazona/administración & dosificación , Rosiglitazona/economía , Rosiglitazona/uso terapéutico , Compuestos de Sulfonilurea/economíaRESUMEN
This paper explores the impacts of a water right's allocative priority-as an indicator of farmers' risk-bearing ability-on land irrigation under water supply uncertainty. We develop and use an economic model to simulate farmers' land irrigation decision and associated economic returns in eastern Idaho. Results indicate that the optimal acreage of land irrigated increases with water right priority when hydroclimate risk exhibits a negatively skewed or right-truncated distribution. Simulation results suggest that prior appropriation enables senior water rights holders to allocate a higher proportion of their land to irrigation, 6 times as much as junior rights holders do, creating a gap in the annual expected net revenue reaching up to $141.4 acre-1 or $55,800 per farm between the two groups. The optimal irrigated acreage, expected net revenue, and shadow value of a water right's priority are subject to substantial changes under a changing climate in the future, where temporal variation in water supply risks significantly affects the profitability of agricultural land use under the priority-based water sharing mechanism.
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Abnormal expression of miRNAs has been implicated in the pathogenesis of human lung cancers, most of which are attributable to cigarette smoke. The mechanisms of action, however, remain obscure. Here, we report that there are decreased expression of miR-218 and increased expression of EZH2 and H3K27me3 during cigarette smoke extract (CSE)-induced transformation of human bronchial epithelial (HBE) cells. Depletion of EZH2 by siRNA or by the EZH2 inhibitor, 3-deazaneplanocin A, attenuated CSE-induced decreases of miR-218 levels and increases of H3K27me3, which epigenetically controls gene transcription, and BMI1, an oncogene. Furthermore, ChIP assays demonstrated that EZH2 and H3K27me3 are enriched at the miR-218-1 promoter in HBE cells exposed to CSE, indicating that EZH2 mediates epigenetic silencing of miR-218 via histone methylation. In addition, miR-218 directly targeted BMI1, through which miR-218 ablates cancer stem cells (CSCs) self-renewal in transformed HBE cells. In CSE-transformed HBE cells, the protein level of Oct-4 and mRNA levels of CD133 and CD44, indicators of the acquisition of CSC-like properties, were reduced by over-expression of miR-218, and over-expression of miR-218 decreased the malignancy of transformed HBE cells. Thus, we conclude that epigenetic silencing of miR-218 via EZH2-mediated H3K27 trimethylation is involved in the acquisition of CSC-like properties and malignant transformation of HBE cells induced by CSE and thereby contributes to the carcinogenesis of cigarette smoke.
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Transformación Celular Neoplásica/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , MicroARNs/genética , Fumar/efectos adversos , Bronquios/citología , Línea Celular , Transformación Celular Neoplásica/efectos de los fármacos , Proteína Potenciadora del Homólogo Zeste 2/genética , Epigénesis Genética/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/patología , Lisina/metabolismo , Metilación/efectos de los fármacos , Proteína Quinasa 7 Activada por Mitógenos/genética , Proteína Quinasa 7 Activada por Mitógenos/metabolismoRESUMEN
Lung cancer is the leading cause of cancer mortality worldwide. A common interest in lung cancer research is the identification of biomarkers for early diagnosis and accurate prognosis. There is increasing evidence that microRNAs (miRNAs) are involved in lung cancer. To explore new biomarkers of chemical exposure in risk assessment of chemical carcinogenesis and lung cancer, we analyzed miRNA expression profiles of human bronchial epithelial (HBE) cells malignantly transformed by arsenite. High-throughput microarray analysis showed that 51 miRNAs were differentially expressed in transformed HBE cells relative to normal HBE cells. In particular, miR-191 was up-regulated in transformed cells. In HBE cells, arsenite induced increases of miR-191 and WT1 levels, decreased BASP1 expression, and activated the Wnt/ß-catenin pathway, effects that were blocked by miR-191 knockdown. In addition, a luciferase reporter assay indicated that BASP1 is a direct target of miR-191. By inhibiting the expression of BASP1, miR-191 increased the expression of WT1 to promote activation of Wnt/ß-catenin pathway. In transformed cells, inhibition of miR-191 expression blocked the epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties of cells and decreased their migratory capacity and neoplastic properties. Thus, these results demonstrate that miR-191 modulates the EMT and the CSC-like properties of transformed cells and indicate that it is an onco-miR involved in the neoplastic and metastatic properties of transformed cells.
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Neoplasias de los Bronquios/patología , Transición Epitelial-Mesenquimal/fisiología , MicroARNs/fisiología , Metástasis de la Neoplasia , Células Madre Neoplásicas/patología , Secuencia de Bases , Neoplasias de los Bronquios/genética , Línea Celular Transformada , Cartilla de ADN , Humanos , MicroARNs/genética , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
The incidence of lung diseases, including cancer, caused by cigarette smoke is increasing, but the molecular mechanisms of gene regulation induced by cigarette smoke remain unclear. This report describes a long noncoding RNA (lncRNA) that is induced by cigarette smoke extract (CSE) and experiments utilizing lncRNAs to integrate inflammation with the epithelial-mesenchymal transition (EMT) in human bronchial epithelial (HBE) cells. The present study shows that, induced by CSE, IL-6, a pro-inflammatory cytokine, leads to activation of STAT3, a transcription activator. A ChIP assay determined that the interaction of STAT3 with the promoter regions of HOX transcript antisense RNA (HOTAIR) increased levels of HOTAIR. Blocking of IL-6 with anti-IL-6 antibody, decreasing STAT3, and inhibiting STAT3 activation reduced HOTAIR expression. Moreover, for HBE cells cultured in the presence of HOTAIR siRNA for 24h, the CSE-induced EMT, formation of cancer stem cells (CSCs), and malignant transformation were reversed. Thus, IL-6, acting on STAT3 signaling, which up-regulates HOTAIR in an autocrine manner, contributes to the EMT and to CSCs induced by CSE. These data define a link between inflammation and EMT, processes involved in the malignant transformation of cells caused by CSE. This link, mediated through lncRNAs, establishes a mechanism for CSE-induced lung carcinogenesis.
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Transformación Celular Neoplásica/metabolismo , Células Epiteliales/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias Pulmonares/etiología , Pulmón/efectos de los fármacos , Células Madre Neoplásicas/efectos de los fármacos , ARN Largo no Codificante/metabolismo , Humo/efectos adversos , Fumar/efectos adversos , Animales , Comunicación Autocrina/efectos de los fármacos , Línea Celular Transformada , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Relación Dosis-Respuesta a Droga , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Interleucina-6/metabolismo , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Interferencia de ARN , ARN Largo no Codificante/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Transfección , Regulación hacia ArribaRESUMEN
Intercellular communications within the cancer microenvironment coordinate the assembly of various cell types. Exosomes are mediators of intercellular communication in immune signaling, tumor promotion, stress responses, and angiogenesis. The present research aimed to determine whether miRNAs secreted from human bronchial epithelial (HBE) cells transformed by 1.0 µM arsenite are transferred into normal HBE cells and are functionally active in the recipient cells. The results show that miR-21 is involved in exosome-mediated intercellular communication between neoplastic and normal HBE cells. Exosomes derived from transformed HBE cells stimulated proliferation of normal HBE cells, whereas exosomes from miR-21 depleted cells failed to stimulate proliferation. In normal HBE cells, the expression of phosphatase and tensin homolog, a target gene for miR-21, was increased by exosomal miR-21, indicating that exogenous miRNAs, via exosomal transport, function-like endogenous miRNAs. Concordantly, specific reduction of miR-21 content in exosome-producing transformed cells abolished the stimulation of proliferation by exosomes. Collectively, the data indicate that transformed HBE cells release exosomes containing miR-21, stimulating proliferation in neighboring normal HBE cells and supporting the concept that exosomal miRNAs are involved in cell-cell communication during carcinogenesis induced by environmental chemicals.
Asunto(s)
Arseniatos/toxicidad , Bronquios/efectos de los fármacos , Proliferación Celular , Transformación Celular Neoplásica/inducido químicamente , Células Epiteliales/efectos de los fármacos , Exosomas/efectos de los fármacos , MicroARNs/metabolismo , Comunicación Paracrina/efectos de los fármacos , Bronquios/metabolismo , Bronquios/patología , Línea Celular Transformada , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Técnicas de Cocultivo , Células Epiteliales/metabolismo , Células Epiteliales/patología , Exosomas/metabolismo , Humanos , Interleucina-6/metabolismo , MicroARNs/genética , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Interferencia de ARN , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Transfección , Regulación hacia ArribaRESUMEN
The Sharpe ratio function is a commonly used risk/return measure in financial econometrics. To estimate this function, most existing methods take a two-step procedure that first estimates the mean and volatility functions separately and then applies the plug-in method. In this paper, we propose a direct method via local maximum likelihood to simultaneously estimate the Sharpe ratio function and the negative log-volatility function as well as their derivatives. We establish the joint limiting distribution of the proposed estimators, and moreover extend the proposed method to estimate the multivariate Sharpe ratio function. We also evaluate the numerical performance of the proposed estimators through simulation studies, and compare them with existing methods. Finally, we apply the proposed method to the three-month US Treasury bill data and that captures a well-known covariate-dependent effect on the Sharpe ratio.