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Pulmonary fibrosis is a common and severe fibrotic lung disease with high morbidity and mortality. Recent studies have reported a large number of unwanted myofibroblasts appearing in pulmonary fibrosis, and shown that the sustained activation of myofibroblasts is essential for unremitting interstitial fibrogenesis. However, the origin of these myofibroblasts remains poorly understood. Here, we create new mouse models of pulmonary fibrosis and identify a previously unknown population of endothelial cell (EC)-like myofibroblasts in normal lung tissue. We show that these EC-like myofibroblasts significantly contribute myofibroblasts to pulmonary fibrosis, which is confirmed by single-cell RNA sequencing of human pulmonary fibrosis. Using the transcriptional profiles, we identified a small molecule that redirects the differentiation of EC-like myofibroblasts and reduces pulmonary fibrosis in our mouse models. Our study reveals the mechanistic underpinnings of the differentiation of EC-like myofibroblasts in pulmonary fibrosis and may provide new strategies for therapeutic interventions.
Assuntos
Fibrose Pulmonar , Camundongos , Animais , Humanos , Fibrose Pulmonar/genética , Miofibroblastos/patologia , Pulmão/patologia , Diferenciação Celular , Modelos Animais de Doenças , Células Endoteliais , FibroseRESUMO
Adipose-derived cells (ADCs) from white adipose tissue are promising stem cell candidates because of their large regenerative reserves and the potential for cardiac regeneration. However, given the heterogeneity of ADC and its unsolved mechanisms of cardiac acquisition, ADC-cardiac transition efficiency remains low. In this study, we explored the heterogeneity of ADCs and the cellular kinetics of 39,432 single-cell transcriptomes along the leukemia inhibitory factor (LIF)-induced ADC-cardiac transition. We identified distinct ADC subpopulations that reacted differentially to LIF when entering the cardiomyogenic program, further demonstrating that ADC-myogenesis is time-dependent and initiates from transient changes in nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. At later stages, pseudotime analysis of ADCs navigated a trajectory with 2 branches corresponding to activated myofibroblast or cardiomyocyte-like cells. Our findings offer a high-resolution dissection of ADC heterogeneity and cell fate during ADC-cardiac transition, thus providing new insights into potential cardiac stem cells.
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Miócitos Cardíacos , Fator 2 Relacionado a NF-E2 , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/farmacologia , RNA-Seq , Diferenciação Celular/genéticaRESUMO
Endothelial-mesenchymal transition (EndMT) drives the endothelium to contribute to vascular calcification in diabetes mellitus. In our previous study, we showed that glycogen synthase kinase-3ß (GSK3ß) inhibition induces ß-catenin and reduces mothers against DPP homolog 1 (SMAD1) to direct osteoblast-like cells toward endothelial lineage, thereby reducing vascular calcification in Matrix Gla Protein (Mgp) deficiency. Here, we report that GSK3ß inhibition reduces vascular calcification in diabetic Ins2Akita/wt mice. Cell lineage tracing reveals that GSK3ß inhibition redirects endothelial cell (EC)-derived osteoblast-like cells back to endothelial lineage in the diabetic endothelium of Ins2Akita/wt mice. We also find that the alterations in ß-catenin and SMAD1 by GSK3ß inhibition in the aortic endothelium of diabetic Ins2Akita/wt mice are similar to Mgp-/- mice. Together, our results suggest that GSK3ß inhibition reduces vascular calcification in diabetic arteries through a similar mechanism to that in Mgp-/- mice.
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Calcificação Vascular , beta Catenina , Camundongos , Animais , beta Catenina/genética , Glicogênio Sintase Quinase 3 beta/genética , Camundongos Endogâmicos C57BL , InsulinaAssuntos
Antagonistas Adrenérgicos beta/farmacologia , Doenças da Aorta/prevenção & controle , Células Endoteliais/efeitos dos fármacos , Etanolaminas/farmacologia , Fatores de Transcrição SOXB1/metabolismo , Calcificação Vascular/prevenção & controle , Animais , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Modelos Animais de Doenças , Regulação para Baixo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Camundongos Knockout , Camundongos Knockout para ApoE , Osteopontina/genética , Osteopontina/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Proteína de Matriz GlaAssuntos
Antagonistas Adrenérgicos beta/farmacologia , Encéfalo/irrigação sanguínea , Células Endoteliais/patologia , Etanolaminas/farmacologia , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Malformações Arteriovenosas Intracranianas/tratamento farmacológico , Fatores de Transcrição SOXB1/metabolismo , Sítios de Ligação , Células Cultivadas , Regulação para Baixo , Células Endoteliais/metabolismo , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Malformações Arteriovenosas Intracranianas/genética , Malformações Arteriovenosas Intracranianas/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição SOXB1/genética , Transdução de SinaisRESUMO
OBJECTIVE: Bone morphogenetic protein (BMP) signaling is intricately involved in adipose tissue development. BMP7 together with BMP4 have been implicated in brown adipocyte differentiation but their roles during development remains poorly specified. Matrix Gla protein (MGP) inhibits BMP4 and BMP7 and is expressed in endothelial and progenitor cells. The objective was to determine the role of MGP in brown adipose tissue (BAT) development. METHODS: The approach included global and cell-specific Mgp gene deletion in combination with RNA analysis, immunostaining, thermogenic activity, and in vitro studies. RESULTS: The results revealed that MGP directs brown adipogenesis at two essential steps. Endothelial-derived MGP limits triggering of white adipogenic differentiation in the perivascular region, whereas MGP derived from adipose cells supports the transition of CD142-expressing progenitor cells to brown adipogenic maturity. Both steps were important to optimize the thermogenic function of BAT. Furthermore, MGP derived from both sources impacted vascular growth. Reduction of MGP in either endothelial or adipose cells expanded the endothelial cell population, suggesting that MGP is a factor in overall plasticity of adipose tissue. CONCLUSION: MGP displays a dual and cell-specific function in BAT, essentially creating a "cellular shuttle" that coordinates brown adipogenic differentiation with vascular growth during development.
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Adipócitos Marrons , Proteína de Matriz Gla , Adipócitos Marrons/metabolismo , Diferenciação Celular , Tecido Adiposo Marrom/metabolismo , Adipogenia/fisiologiaRESUMO
Carbon/cobalt ferromagnetic light composites with high performance of microwave absorbing properties were prepared by hydrothermal method using starch and hollow cobalt ferrites. It was concluded that after carbonization the spinel structure ferrites changed to Co3Fe7 alloys and the temperature of graphitization was significantly decreased for the catalytic of CoFe2O4/Co3Fe7. The increase of carbon content, and exist of CoFe2O4/Co3Fe7 heightened the microwave absorbing properties. Electromagnetic parameters were tested with 40% of the titled materials and 60% of paraffin wax composites by using HP8722ES vector network analyzer. The reflection was also simulated through transmission line theory. The microwave absorbers exhibited a maximum reflection loss -43 dB and the electromagnetic wave absorption less than -10 dB was found to exceed 3.0 GHz between 11.6 GHz and 15 GHz for an absorber thickness of 2 mm.
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Glucocorticoid-induced bone loss is a toxic effect of long-term therapy with glucocorticoids resulting in a significant increase in the risk of fracture. Here, we find that glucocorticoids reciprocally convert osteoblast-lineage cells into endothelial-like cells. This is confirmed by lineage tracing showing the induction of endothelial markers in osteoblast-lineage cells following glucocorticoid treatment. Functional studies show that osteoblast-lineage cells isolated from glucocorticoid-treated mice lose their capacity for bone formation but simultaneously improve vascular repair. We find that the glucocorticoid receptor directly targets Foxc2 and Osterix, and the modulations of Foxc2 and Osterix drive the transition of osteoblast-lineage cells to endothelial-like cells. Together, the results suggest that glucocorticoids suppress osteogenic capacity and cause bone loss at least in part through previously unrecognized osteoblast-endothelial transitions.
Assuntos
Doenças Ósseas Metabólicas , Glucocorticoides , Camundongos , Animais , Glucocorticoides/efeitos adversos , Osteoblastos , OsteogêneseRESUMO
Glucocorticoid-induced bone loss is a severe and toxic effect of long-term therapy with glucocorticoids, which are currently prescribed for millions of people worldwide. Previous studies have uncovered that glucocorticoids reciprocally converted osteoblast lineage cells into endothelial-like cells to cause bone loss and showed that the modulations of Foxc2 and Osterix were the causative factors that drove this harmful transition of osteoblast lineage cells. Here, we find that the inhibition of aurora kinase A halts this transition and prevents glucocorticoid-induced bone loss. We find that aurora A interacts with the glucocorticoid receptor and show that this interaction is required for glucocorticoids to modulate Foxc2 and Osterix. Together, we identify a new potential approach to counteracting unwanted transitions of osteoblast lineage cells in glucocorticoid treatment and may provide a novel strategy for ameliorating glucocorticoid-induced bone loss.
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Aurora Quinase A , Doenças Ósseas Metabólicas , Glucocorticoides , Glucocorticoides/efeitos adversos , Osteoblastos , Receptores de Glucocorticoides , AnimaisRESUMO
Transitions between cell fates commonly occur in development and disease. However, reversing an unwanted cell transition in order to treat disease remains an unexplored area. Here, we report a successful process of guiding ill-fated transitions toward normalization in vascular calcification. Vascular calcification is a severe complication that increases the all-cause mortality of cardiovascular disease but lacks medical therapy. The vascular endothelium is a contributor of osteoprogenitor cells to vascular calcification through endothelial-mesenchymal transitions, in which endothelial cells (ECs) gain plasticity and the ability to differentiate into osteoblast-like cells. We created a high-throughput screening and identified SB216763, an inhibitor of glycogen synthase kinase 3 (GSK3), as an inducer of osteoblastic-endothelial transition. We demonstrated that SB216763 limited osteogenic differentiation in ECs at an early stage of vascular calcification. Lineage tracing showed that SB216763 redirected osteoblast-like cells to the endothelial lineage and reduced late-stage calcification. We also found that deletion of GSK3ß in osteoblasts recapitulated osteoblastic-endothelial transition and reduced vascular calcification. Overall, inhibition of GSK3ß promoted the transition of cells with osteoblastic characteristics to endothelial differentiation, thereby ameliorating vascular calcification.
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Diferenciação Celular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Calcificação Vascular/metabolismo , Animais , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Indóis/farmacologia , Maleimidas/farmacologia , Camundongos , Camundongos Transgênicos , Inibidores de Proteínas Quinases/farmacologiaRESUMO
RNA interference (RNAi) is a posttranscriptional gene silencing mechanism triggered by double-stranded RNA (dsRNA), which causes degradation of homologous mRNAs. RNAi has been observed in a wide range of eukaryotes, including fungi, plants and animals. In vertebrates, long dsRNA activates the interferon response and yields nonspecific degradation of mRNA. In contrast, small interference RNA (siRNA) duplexes with a length of 21-23 nucleotides trigger specific gene silencing and thus are widely used in gene function studies. The use of siRNA for gene silencing in zebrafish has rarely been reported. In this report, we studied mammalian U6 promoter-driven siRNA-mediated RNA interference in zebrafish. The well characterized genes Myf5, Dlg3 and Nacre were selected as targets. Two to four target siRNAs were synthesized with incorporation of the U6 promoter. Constructs were introduced into early zebrafish embryos through microinjection, followed by in situ hybridization and embryonic development was monitored to determine whether U6 promoter-driven siRNAs could efficiently suppress specific gene expression. We showed that these siRNAs could partially suppress endogenous gene expression and that the siRNA efficiency varied at different targeted positions. However, the U6 promoter-driven siRNAs may also have induced nonspecific gene suppression (off-target effects). It appears that, despite the findings of previous reports, the current methodology of siRNA interference is not practical for studying gene function during early zebrafish development.
Assuntos
Proteínas de Membrana/genética , Fator de Transcrição Associado à Microftalmia/genética , Fator Regulador Miogênico 5/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Nuclear Pequeno/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Sequência de Bases , Embrião não Mamífero/metabolismo , Regiões Promotoras Genéticas , Peixe-Zebra/embriologiaRESUMO
AIMS: Several signaling pathways contribute to endothelial-mesenchymal transitions and vascular calcification, including bone morphogenetic protein (BMP) and transforming growth factor (TGF) ß signaling. The transcription factor homeobox D3 (Hoxd3) is known to regulate an invasive endothelial phenotype, and the aim of the study is to determine if HOXD3 modulates BMP and TGFß signaling in the endothelium. METHODS AND RESEARCH: We report that the endothelium with high BMP activity due to the loss of BMP inhibitor matrix Gla protein (MGP) shows induction of Hoxd3. HOXD3 is part of a BMP-triggered cascade. When activated by BMP9, activin receptor-like kinase (ALK) 1 induces HOXD3 expression. Hoxd3 promoter is a direct target of phosphorylated (p) SMAD1, a mediator of BMP signaling. High BMP activity further results in enhanced TGFß signaling due to induction of TGFß1 and its receptor, ALK5. This is mediated by HOXD3, which directly targets the Tgfb1 promoter. Finally, TGFß1 and BMP9 stimulate the expression of MGP, which limits the enhanced ALK1 induction by counteracting BMP4. The cascade of BMP9-HOXD3-TGFß also affects Notch signaling and angiogenesis through induction of Notch ligand Jagged 2 and suppression of Notch ligand delta-like 4 (Dll4). CONCLUSION: The results suggest that HOXD3 is a novel link between BMP9/ALK1 and TGFß1/ALK5 signaling. TRANSLATIONAL PERSPECTIVE: BMP and TGFß signaling are instrumental in vascular disease such as vascular calcification and atherosclerosis. This study demonstrated a novel type of cross talk between endothelial BMP and TGFß signaling as mediated by HOXD3. The results provide a possible therapeutic approach to control dysfunctional BMP and TGFß signaling by regulating HOXD3.
Assuntos
Receptores de Activinas Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Neovascularização Fisiológica , Proteínas/fisiologia , Receptores Notch/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Receptores de Activinas Tipo II/genética , Animais , Proteínas de Ligação a DNA/genética , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Receptores Notch/genética , Transdução de Sinais , Fator de Crescimento Transformador beta1/genéticaRESUMO
Notch signaling and Sry-box (Sox) family transcriptional factors both play critical roles in endothelial cell (EC) differentiation in vascularization. Recent studies have shown that excessive Notch signaling induces Sox2 to cause cerebral arteriovenous malformations (AVMs). Here, we examine human pulmonary AVMs and find no induction of Sox2. Results of epigenetic studies also show less alteration of Sox2-DNA binding in pulmonary AVMs than in cerebral AVMs. We identify high expression of ski-interacting protein (Skip) in brain ECs, a Notch-associated chromatin-modifying protein that is lacking in lung ECs. Knockdown of Skip abolished Notch-induction of Sox2 in brain ECs, while restoration of Skip in lung ECs enabled Notch-mediated Sox2 induction. The results suggest that Skip is a key factor for induction of Sox2 in cerebral AVMs.
Assuntos
Malformações Arteriovenosas Intracranianas/metabolismo , Coativadores de Receptor Nuclear/metabolismo , Receptores Notch/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , DNA/metabolismo , Células Endoteliais/metabolismo , Humanos , Malformações Arteriovenosas Intracranianas/patologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Modelos Biológicos , Ligação Proteica , Proteínas/metabolismo , Artéria Pulmonar/patologiaRESUMO
The carbon fibers were ultrasonically treated under nickel chloride solution, and nickel ions were attached to the surface of the carbon fibers, which replaces the nitric acid oxidation method used in the original electroless nickel plating. Electroless nickel plating was performed on the surface of the carbon fibers using a palladium-free technique successfully. Nickel-plated carbon fibers with a higher weight gain ratio than the original method was obtained. XPS was used to study the functional group changes on the surface of carbon fibers and the chemical valence of nickel element. The mechanism of ultrasonic treatment on the surface of carbon fibers was analyzed, and the effect of ultrasonic treatment on the weight gain rate of nickel-plated carbon fibers was discussed. The results show that the ultrasonic treatment under nickel chloride solution can significantly increase the content of polar functional groups on the surface of carbon fibers and can promote the bonding of the carboxyl group on the surface of the carbon fibers with the hydrated nickel ion to form CFCOONi. The formation of CFCOONi enhances the bonding strength between the nano-nickel particles and the carbon fibers, thereby increasing the bonding strength between the plating layer and the substrate. The concentration of nickel chloride solution and ultrasonic power during ultrasonic treatment has a great influence on the weight gain rate of carbon fibers after electroless plating. When the concentration is greater than 10â¯g/L, the higher the concentration, the smaller the weight gain rate. When the treatment concentration is less than 10â¯g/L, the concentration has little effect on the weight gain rate. The optimum treatment concentration obtained in the experiment was 7â¯g/L. As the ultrasonic power increases, the weight gain rate increases first and then decreases, and the optimal ultrasonic power is 80â¯W. Ultrasonic time does not have a large effect on the weight gain rate, but the too low ultrasonic time will cause a slight decrease in the weight gain rate.
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Breast cancer metastasis suppressor 1 (BRMS1) is a tumor metastasis suppressor implicated in multiple steps during the metastatic cascade. Many proteins interacting with BRMS1 have been identified to unravel the intracellular signaling mechanisms. In the present study, we report that FANCI is a novel interacting protein of BRMS1 as determined by coimmunoprecipitation assay. The linker region between two coiledcoil motifs of BRMS1 is required for BRMS1FANCI interaction. FANCI is an essential protein in the Fanconi anemia (FA) pathway responsible for the repair of DNA interstrand crosslinks (ICLs). We demonstrated that knockdown or knockout of BRMS1 significantly diminished the monoubiquitination of FANCI and FANCD2 in response to DNA ICL damage. BRMS1deficient cells exhibited suppressed FANCD2 foci formation and hypersensitivity to ICLs. Moreover, rescue assays by utilizing different BRMS1 constructs suggested that BRMS1FANCI interaction is necessary for the regulatory role of BRMS1 in the FA pathway. Overall, our findings characterize BRMS1 as a novel regulatory protein functioning in the DNA repair pathway via protein interaction.
Assuntos
Dano ao DNA/fisiologia , DNA/metabolismo , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Proteínas Repressoras/metabolismo , Linhagem Celular , Reparo do DNA/fisiologia , Anemia de Fanconi/metabolismo , Células HEK293 , Humanos , Transdução de Sinais/fisiologia , Ubiquitinação/fisiologiaRESUMO
One of the most fundamental parameters of any photovoltaic material is its quasi-Fermi level splitting (∆µ) under illumination. This quantity represents the maximum open-circuit voltage (Voc ) that a solar cell fabricated from that material can achieve. Herein, a contactless, nondestructive method to quantify this parameter for atomically thin 2D transition metal dichalcogenides (TMDs) is reported. The technique is applied to quantify the upper limits of Voc that can possibly be achieved from monolayer WS2 , MoS2 , WSe2 , and MoSe2 -based solar cells, and they are compared with state-of-the-art perovskites. These results show that Voc values of ≈1.4, ≈1.12, ≈1.06, and ≈0.93 V can be potentially achieved from solar cells fabricated from WS2 , MoS2 , WSe2 , and MoSe2 monolayers at 1 Sun illumination, respectively. It is also observed that ∆µ is inhomogeneous across different regions of these monolayers. Moreover, it is attempted to engineer the observed ∆µ heterogeneity by electrically gating the TMD monolayers in a metal-oxide-semiconductor structure that effectively changes the doping level of the monolayers electrostatically and improves their ∆µ heterogeneity. The values of ∆µ determined from this work reveal the potential of atomically thin TMDs for high-voltage, ultralight, flexible, and eye-transparent future solar cells.
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Zinc finger proteins (ZNFs) are one of the most abundant proteins in eukaryotic genomes with extraordinarily diverse functions. ZNF233 is located on 19q13.31 and encodes a 670-amino acid protein belonging to the Krüppel C2H2-type ZNF family. However, little is known about the role of ZNF233 in cancer progression. In this study, we reported for the first time that ZNF233 mRNA was remarkably up-regulated in hepatocellular carcinoma (HCC) tissues in comparison with corresponding non-tumorous normal liver tissues. ZNF233 expression level was correlated with tumor grade, tumor stage and prognosis of HCC patients. We further investigated the effect of ZNF233 on HCC cell growth. It is found that overexpression of ZNF233 in SMMC-7721 could promote G1/S transition and thus accelerate cell growth ratio. Consistently, knockdown of ZNF233 in QGY-7701 cells successfully suppressed cell proliferation in vitro and in vivo. Further immunohistochemical staining revealed a reduced Ki-67-positive cell percentage in xenografted tumor derived from ZNF233-knocking down cells. Taken together, these results demonstrate a positive role of ZNF233 in regulating HCC cell growth. ZNF233 might be developed as a novel biomarker and a potential therapeutic target for HCC.
Assuntos
Carcinoma Hepatocelular/patologia , Técnicas de Silenciamento de Genes/métodos , Neoplasias Hepáticas/patologia , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Regulação para Cima , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Gradação de Tumores , Transplante de Neoplasias , Prognóstico , Dedos de ZincoRESUMO
Tumor metastasis suppressor factor BRMS1 can regulate the metastasis of breast cancer and other tumors. Here we report scinderin (SCIN) as a novel transcriptional target of BRMS1. SCIN protein belongs to the cytoskeletal gelsolin protein superfamily and its involvement in tumorigenesis remains largely illusive. An inverse correlation between the expression levels of BRMS1 and SCIN was observed in hepatocellular carcinoma (HCC) cells and tissues. On the molecular level, BRMS1 binds to SCIN promoter and exerts a suppressive role in regulating SCIN transcription. FACS analysis and caspase 9 immunoblot reveal that knockdown of SCIN expression can sensitize HCC cells to chemotherapeutic drugs, leading to suppression of tumor growth in vivo. Consistently, overexpression of SCIN protects cells from apoptotic death, contributing to increased xenografted HCC cell growth. In summary, our study reveals SCIN as a functional apoptosis regulator as well as a novel target of BRMS1 during HCC tumorigenesis. Inhibition of SCIN might bring a potential cancer therapy approach.
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Breast cancer metastasis suppressor 1 (BRMS1) can specifically regulate tumor metastasis in many cancers. Our previous studies have demonstrated that BRMS1 can promote cell apoptosis through regulating osteopontin (OPN) expression in hepatocellular carcinoma (HCC) cells. However, the transcriptional targets of BRMS1 have not been thoroughly studied. In this study, death-associated protein kinase 1 (DAPK1), a tumor suppressor gene with multiple roles in regulating cell death, was identified as a potential transcriptional target of BRMS1 in the whole genome expression microarray. Quantitative real-time PCR and western blot analysis of HCC cells overexpressing BRMS1 further confirmed the transcriptional regulation relationship between BRMS1 and DAPK1. Moreover, DAPK1 expression was frequently decreased or even lost in HCC tissue samples by comparison with neighboring pathologically normal liver tissue, which was consistent with the decreased BRMS1 expression pattern. To unravel the molecular mechanism of BRMS1 in regulating DAPK1, a series of deletion mutants of DAPK1 promoter was subjected to luciferase assay. The luciferase units of -200 to -80 bp region, with two tandem putative NF-κB binding sites, were specifically enhanced by BRMS1 expression. Site-directed mutants of NF-κB binding sites blocked the transcriptional activation effect. In addition, the binding capability of BRMS1 and the putative NF-κB binding sites were demonstrated in the chromatin immunoprecipitation (ChIP) assay. In conclusion, our study characterized DAPK1 as a novel transcriptional target of BRMS1. Transcriptional activation of DAPK1 might be another important mechanism accounting for the metastasis suppressive activity of BRMS1.
Assuntos
Carcinoma Hepatocelular/genética , Proteínas Quinases Associadas com Morte Celular/genética , Neoplasias Hepáticas/genética , Proteínas Repressoras/genética , Ativação Transcricional/genética , Apoptose/genética , Sítios de Ligação , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas Quinases Associadas com Morte Celular/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , NF-kappa B/genética , Metástase Neoplásica , Regiões Promotoras Genéticas , Proteínas Repressoras/biossíntese , Deleção de Sequência , Análise Serial de TecidosRESUMO
The new coordination polymer of sodium trinitrophloroglucinate, [Na(H2TNPG)(H2O)2]n, was synthesized by reacting trinitrophloroglucinol (H3TNPG) with NaHCO3 in aqueous solution and [Na(H2TNPG)(H2O)2]n was recrystallized to be yellow single crystal. The title compound was characterized by using elemental analysis and Fourier transform infrared (FT-IR) spectrum. Its crystal structure was determined by single crystal X-ray diffraction analysis. The crystalline belongs to monoclinic system and C2/c space group. Each Na+ ion is six-coordinated to one H2TNPG- anion and four water molecules in which the oxygen atoms in the water molecules act as bridging atoms. Coordination bonds, electrostatic interaction and intermolecular hydrogen bonds assemble the ions into network structures. The thermal decomposition mechanism of the complex was studied by using differential scanning calorimetry (DSC), thermogravimetry/derivative thermogravimetry (TG/DTG) and FT-IR techniques. Under nitrogen atmosphere with a heating rate of 10 degrees C/min the thermal decomposition of the complex contained one endothermic and five exothermic processes. Two intense exothermic decomposition processes were observed in the range of 173-228 degrees C suggesting its energetic nature and the solid decomposition residue at 500 degrees C was sodium isonitrile. Explosive properties revealed that the compound is sensitive to mechanical stimuli. All properties data observed show that the title compound has explosive properties and can act as components of ecologically clean initiating compositions.