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1.
Haematologica ; 109(2): 411-421, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584287

RESUMO

Leukemia stem cells (LSC) represent a crucial and rare subset of cells present in acute myeloid leukemia (AML); they play a pivotal role in the initiation, maintenance, and relapse of this disease. Targeting LSC holds great promise for preventing AML relapse and improving long-term outcomes. However the precise molecular mechanisms governing LSC self-renewal are still poorly understood. Here, we present compelling evidence that the expression of miR-30e-5p, a potential tumor-suppressive microRNA, is significantly lower in AML samples than in healthy bone marrow samples. Forced expression of miR- 30e effectively inhibits leukemogenesis, impairs LSC self-renewal, and delays leukemia progression. Mechanistically, Cyb561 acts as a direct target of miR-30e-5p in LSC, and its deficiency restricts the self-renewal of LSC by activating reactive oxygen series signaling and markedly prolongs recipients' survival. Moreover, genetic or pharmacological overexpression of miR-30e-5p or knockdown of Cyb561 suppresses the growth of human AML cells. In conclusion, our findings establish the crucial role of the miR-30e-5p/Cyb561/ROS axis in finely regulating LSC self-renewal, highlighting Cyb561 as a potential therapeutic target for LSC-directed therapies.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Humanos , Espécies Reativas de Oxigênio , Autorrenovação Celular/genética , MicroRNAs/genética , Transdução de Sinais , Recidiva , Proliferação de Células/genética , Linhagem Celular Tumoral
2.
Prostate ; 75(9): 907-16, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25728608

RESUMO

BACKGROUND: PTEN/AKT signaling plays a key role in prostate cancer development and maintenance of prostate cancer stem cells. How other oncogenes or tumor suppressors interact with this pathway remain to be elucidated. SLUG is an zinc finger transcription factor of the Snail superfamily, and it promotes cancer metastasis and determines the mammary stem cell state. METHODS: SLUG was overexpressed in cells by retroviral vector and knockdown of SLUG and PTEN was mediated by shRNAs-expressing lentiviruses. Expression level of SLUG and PTEN was examined by Western blot, RT-PCR, and qPCR analyses. PTEN promoter activity was measured by luciferase reporter assay. ChIP assay was used to measure the binding between SLUG and the PTEN promoter in vivo. RESULT: We showed that overexpression of SLUG decreased expression of PTEN tumor repressor in prostate cancer cell lines 22RV1 and DU145; conversely, knockdown of SLUG expression elevated PTEN expresson at both protein and RNA level in these cells. We demonstrated that SLUG overexpression inhibits PTEN promoter activity through the proximal promoter region in prostate cancer cells. By ChIP assay, we confirmed that SLUG directly binds to the PTEN promoter region covering the E-box sites. We also showed that Slug deficiency leads to an increased expression of PTEN in mouse embryo fibroblasts and prostate tissues. Importantly, we found that overexpression of SLUG increases drug resistance of DU145 prostate cancer cell line and knockdown of SLUG by shRNA sensitizes DU145 cell line to chemotherapeutic drugs. We further demonstrated that PTEN knockdown converts drug sensitivity of DU145 cells expressing SLUG shRNA to anticancer drugs. CONCLUSION: We provide compelling evidence showing that PTEN is a direct functional target of SLUG. Our findings offer new insight in the regulation of the PTEN/AKT pathway and provide a molecular basis for potential targeted therapies of prostate cancer Prostate 75:907-916, 2015. © 2015 Wiley Periodicals, Inc.


Assuntos
PTEN Fosfo-Hidrolase/biossíntese , Neoplasias da Próstata/metabolismo , Fatores de Transcrição/biossíntese , Animais , Western Blotting , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/genética , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , RNA Neoplásico/química , RNA Neoplásico/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética
3.
Nat Med ; 13(1): 78-83, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17159988

RESUMO

Interstitial loss of all or part of the long arm of chromosome 5, or del(5q), is a frequent clonal chromosomal abnormality in human myelodysplastic syndrome (MDS, a preleukemic disorder) and acute myeloid leukemia (AML), and is thought to contribute to the pathogenesis of these diseases by deleting one or more tumor-suppressor genes. Although a major commonly deleted region (CDR) has been delineated on chromosome band 5q31.1 (refs. 3-7), attempts to identify tumor suppressors within this band have been unsuccessful. We focused our analysis of gene expression on RNA from primitive leukemia-initiating cells, which harbor 5q deletions, and analyzed 12 genes within the CDR that are expressed by normal hematopoietic stem cells. Here we show that the gene encoding alpha-catenin (CTNNA1) is expressed at a much lower level in leukemia-initiating stem cells from individuals with AML or MDS with a 5q deletion than in individuals with MDS or AML lacking a 5q deletion or in normal hematopoietic stem cells. Analysis of HL-60 cells, a myeloid leukemia line with deletion of the 5q31 region, showed that the CTNNA1 promoter of the retained allele is suppressed by both methylation and histone deacetylation. Restoration of CTNNA1 expression in HL-60 cells resulted in reduced proliferation and apoptotic cell death. Thus, loss of expression of the alpha-catenin tumor suppressor in hematopoietic stem cells may provide a growth advantage that contributes to human MDS or AML with del(5q).


Assuntos
Transformação Celular Neoplásica , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Células Progenitoras Mieloides/patologia , alfa Catenina/genética , Doença Aguda , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HL-60 , Humanos , Ácidos Hidroxâmicos/farmacologia , Hibridização in Situ Fluorescente/métodos , Células K562 , Leucemia Mieloide/sangue , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Mutação , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Células Progenitoras Mieloides/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Células U937 , alfa Catenina/metabolismo
4.
Cell Rep ; 43(3): 113875, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38451818

RESUMO

Liver injury stimulates hepatocyte replication and hepatic stellate cell (HSC) activation, thereby driving liver regeneration. Aberrant HSC activation induces liver fibrosis. However, mechanisms underlying liver regeneration and fibrosis remain poorly understood. Here, we identify hepatic Snai1 and Snai2 as important transcriptional regulators for liver regeneration and fibrosis. Partial hepatectomy or CCl4 treatment increases occupancies of Snai1 and Snai2 on cyclin A2 and D1 promoters in the liver. Snai1 and Snai2 in turn increase promoter H3K27 acetylation and cyclin A2/D1 expressions. Hepatocyte-specific deletion of both Snai1 and Snai2, but not one alone, suppresses liver cyclin A2/D1 expression and regenerative hepatocyte proliferation after hepatectomy or CCl4 treatments but augments CCl4-stimulated HSC activation and liver fibrosis. Conversely, Snai2 overexpression in the liver enhances hepatocyte replication and suppresses liver fibrosis after CCl4 treatment. These results suggest that hepatic Snai1 and Snai2 directly promote, via histone modifications, reparative hepatocyte replication and indirectly inhibit liver fibrosis.


Assuntos
Ciclina A2 , Regeneração Hepática , Animais , Camundongos , Ciclina A2/metabolismo , Hepatectomia , Fígado/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Regeneração Hepática/fisiologia
5.
Adv Mater ; 36(26): e2309770, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447017

RESUMO

Percutaneous thermotherapy, a minimally invasive operational procedure, is employed in the ablation of deep tumor lesions by means of target-delivering heat. Conventional thermal ablation methods, such as radiofrequency or microwave ablation, to a certain extent, are subjected to extended ablation time as well as biosafety risks of unwanted overheating. Given its effectiveness and safety, percutaneous thermotherapy gains a fresh perspective, thanks to magnetic hyperthermia. In this respect, an injectable- and magnetic-hydrogel-construct-based thermal ablation agent is likely to be a candidate for the aforementioned clinical translation. Adopting a simple and environment-friendly strategy, a magnetic colloidal hydrogel injection is introduced by a binary system comprising super-paramagnetic Fe3O4 nanoparticles and gelatin nanoparticles. The colloidal hydrogel constructs, unlike conventional bulk hydrogel, can be easily extruded through a percutaneous needle and then self-heal in a reversible manner owing to the unique electrostatic cross-linking. The introduction of magnetic building blocks is exhibited with a rapid magnetothermal response to an alternating magnetic field. Such hydrogel injection is capable of generating heat without limitation of deep penetration. The materials achieve outstanding therapeutic results in mouse and rabbit models. These findings constitute a new class of locoregional interventional thermal therapies with minimal collateral damages.


Assuntos
Carcinoma Hepatocelular , Coloides , Hidrogéis , Neoplasias Hepáticas , Animais , Coelhos , Camundongos , Hidrogéis/química , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Coloides/química , Gelatina/química , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Hipertermia Induzida/métodos , Linhagem Celular Tumoral , Injeções , Nanopartículas Magnéticas de Óxido de Ferro/química
6.
J Clin Invest ; 133(4)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36512408

RESUMO

Leptin exerts its biological actions by activating the long-form leptin receptor (LepRb). LepRb signaling impairment and leptin resistance are believed to cause obesity. The transcription factor Slug - also known as Snai2 - recruits epigenetic modifiers and regulates gene expression by an epigenetic mechanism; however, its epigenetic action has not been explored in leptin resistance. Here, we uncover a proobesity function of neuronal Slug. Hypothalamic Slug was upregulated in obese mice. LepRb+ cell-specific Slug-knockout (SlugΔLepRb) mice were resistant to diet-induced obesity, type 2 diabetes, and liver steatosis and experienced decreased food intake and increased fat thermogenesis. Leptin stimulated hypothalamic Stat3 phosphorylation and weight loss to a markedly higher level in SlugΔLepRb than in Slugfl/fl mice, even before their body weight divergence. Conversely, hypothalamic LepRb+ neuron-specific overexpression of Slug, mediated by AAV-hSyn-DIO-Slug transduction, induced leptin resistance, obesity, and metabolic disorders in mice on a chow diet. At the genomic level, Slug bound to and repressed the LepRb promoter, thereby inhibiting LepRb transcription. Consistently, Slug deficiency decreased methylation of LepRb promoter H3K27, a repressive epigenetic mark, and increased LepRb mRNA levels in the hypothalamus. Collectively, these results unravel what we believe to be a previously unrecognized hypothalamic neuronal Slug/epigenetic reprogramming/leptin resistance axis that promotes energy imbalance, obesity, and metabolic disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Obesidade , Receptores para Leptina , Fatores de Transcrição da Família Snail , Animais , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Hipotálamo/metabolismo , Leptina/genética , Leptina/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo , Receptores para Leptina/genética , Receptores para Leptina/metabolismo , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
7.
Blood ; 115(9): 1709-17, 2010 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-20032500

RESUMO

Both extrinsic and intrinsic mechanisms tightly govern hematopoietic stem cell (HSC) decisions of self-renewal and differentiation. However, transcription factors that can selectively regulate HSC self-renewal division after stress remain to be identified. Slug is an evolutionarily conserved zinc-finger transcription factor that is highly expressed in primitive hematopoietic cells and is critical for the radioprotection of these key cells. We studied the effect of Slug in the regulation of HSCs in Slug-deficient mice under normal and stress conditions using serial functional assays. Here, we show that Slug deficiency does not disturb hematopoiesis or alter HSC homeostasis and differentiation in bone marrow but increases the numbers of primitive hematopoietic cells in the extramedullary spleen site. Deletion of Slug enhances HSC repopulating potential but not its homing and differentiation ability. Furthermore, Slug deficiency increases HSC proliferation and repopulating potential in vivo after myelosuppression and accelerates HSC expansion during in vitro culture. Therefore, we propose that Slug is essential for controlling the transition of HSCs from relative quiescence under steady-state condition to rapid proliferation under stress conditions. Our data suggest that inhibition of Slug in HSCs may present a novel strategy for accelerating hematopoietic recovery, thus providing therapeutic benefits for patients after clinical myelosuppressive treatment.


Assuntos
Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Regeneração/fisiologia , Fatores de Transcrição/deficiência , Animais , Transplante de Medula Óssea , Diferenciação Celular , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Fluoruracila/toxicidade , Hematopoese Extramedular/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Transcrição da Família Snail , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
8.
Blood ; 115(23): 4707-14, 2010 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20360471

RESUMO

Bone marrow injury is a major adverse side effect of radiation and chemotherapy. Attempts to limit such damage are warranted, but their success requires a better understanding of how radiation and anticancer drugs harm the bone marrow. Here, we report one pivotal role of the BH3-only protein Puma in the radiosensitivity of hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs). Puma deficiency in mice confers resistance to high-dose radiation in a hematopoietic cell-autonomous manner. Unexpectedly, loss of one Puma allele is sufficient to confer mice radioresistance. Interestingly, null mutation in Puma protects both primitive and differentiated hematopoietic cells from damage caused by low-dose radiation but selectively protects HSCs and HPCs against high-dose radiation, thereby accelerating hematopoietic regeneration. Consistent with these findings, Puma is required for radiation-induced apoptosis in HSCs and HPCs, and Puma is selectively induced by irradiation in primitive hematopoietic cells, and this induction is impaired in Puma-heterozygous cells. Together, our data indicate that selective targeting of p53 downstream apoptotic targets may represent a novel strategy to protecting HSCs and HPCs in patients undergoing intensive cancer radiotherapy and chemotherapy.


Assuntos
Proteínas Reguladoras de Apoptose , Apoptose/efeitos da radiação , Raios gama/efeitos adversos , Células-Tronco Hematopoéticas/metabolismo , Tolerância a Radiação/fisiologia , Proteínas Supressoras de Tumor , Animais , Apoptose/fisiologia , Relação Dose-Resposta à Radiação , Camundongos , Camundongos Knockout , Mutação , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
9.
Mol Cancer ; 10: 139, 2011 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-22074556

RESUMO

BACKGROUND: SLUG is a zinc-finger transcription factor of the Snail/Slug zinc-finger family that plays a role in migration and invasion of tumor cells. Mechanisms by which SLUG promotes migration and invasion in prostate cancers remain elusive. METHODS: Expression level of CXCR4 and CXCL12 was examined by Western blot, RT-PCR, and qPCR analyses. Forced expression of SLUG was mediated by retroviruses, and SLUG and CXCL12 was downregulated by shRNAs-expressing lentiviruses. Migration and invasion of prostate cancer were measured by scratch-wound assay and invasion assay, respectively. RESEARCH: We demonstrated that forced expression of SLUG elevated CXCR4 and CXCL12 expression in human prostate cancer cell lines PC3, DU145, 22RV1, and LNCaP; conversely, reduced expression of SLUG by shRNA downregulated CXCR4 and CXCL12 expression at RNA and protein levels in prostate cancer cells. Furthermore, ectopic expression of SLUG increased MMP9 expression and activity in PC3, 22RV1, and DU-145 cells, and SLUG knockdown by shRNA downregulated MMP9 expression. We showed that CXCL12 is required for SLUG-mediated MMP9 expression in prostate cancer cells. Moreover, we found that migration and invasion of prostate cancer cells was increased by ectopic expression of SLUG and decreased by SLUG knockdown. Notably, knockdown of CXCL12 by shRNA impaired SLUG-mediated migration and invasion in prostate cancer cells. Lastly, our data suggest that CXCL12 and SLUG regulate migration and invasion of prostate cancer cells independent of cell growth. CONCLUSION: We provide the first compelling evidence that upregulation of autocrine CXCL12 is a major mechanism underlying SLUG-mediated migration and invasion of prostate cancer cells. Our findings suggest that CXCL12 is a therapeutic target for prostate cancer metastasis.


Assuntos
Movimento Celular , Quimiocina CXCL12/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Receptores CXCR4/metabolismo , Fatores de Transcrição/genética , Linhagem Celular Tumoral , Quimiocina CXCL12/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica , Neoplasias da Próstata/metabolismo , Receptores CXCR4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo
10.
J Cell Biochem ; 109(2): 363-74, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19950207

RESUMO

The signals that direct pluripotent stem cell differentiation into lineage-specific cells remain largely unknown. Here, we investigated the roles of BMP on vascular progenitor development from human embryonic stem cells (hESCs). In a serum-free condition, hESCs sequentially differentiated into CD34+CD31-, CD34+CD31+, and then CD34-CD31+ cells during vascular cell development. CD34+CD31+ cells contained vascular progenitor population that gives rise to endothelial cells and smooth muscle cells. BMP4 promoted hESC differentiation into CD34+CD31+ cells at an early stage. In contrast, TGFbeta suppressed BMP4-induced CD34+CD31+ cell development, and promoted CD34+CD31- cells that failed to give rise to either endothelial or smooth muscle cells. The BMP-Smad inhibitor, dorsomorphin, inhibited phosphorylation of Smad1/5/8, and blocked hESC differentiation to CD34+CD31+ progenitor cells, suggesting that BMP Smad-dependent signaling is critical for CD34+CD31+ vascular progenitor development. Our findings provide new insight into how pluripotent hESCs differentiate into vascular cells.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula , Células-Tronco Embrionárias/citologia , Neovascularização Fisiológica , Proteínas Smad/metabolismo , Antígenos CD34 , Proteína Morfogenética Óssea 4/antagonistas & inibidores , Proteína Morfogenética Óssea 4/farmacologia , Diferenciação Celular/fisiologia , Linhagem Celular , Meios de Cultura Livres de Soro , Células-Tronco Embrionárias/metabolismo , Células Endoteliais/citologia , Humanos , Músculo Liso Vascular/citologia , Fosforilação , Molécula-1 de Adesão Celular Endotelial a Plaquetas , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais , Fator de Crescimento Transformador beta/farmacologia
11.
J Cell Biochem ; 111(1): 29-39, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20506197

RESUMO

The molecules and environment that direct pluripotent stem cell differentiation into cardiomyocytes are largely unknown. Here, we determined a critical role of receptor tyrosine kinase, EphB4, in regulating cardiomyocyte generation from embryonic stem (ES) cells through endothelial cells. The number of spontaneous contracting cardiomyocytes, and the expression of cardiac-specific genes, including alpha-MHC and MLC-2V, was significantly decreased in EphB4-null ES cells. EphB4 was expressed in endothelial cells underneath contracting cardiomyocytes, but not in cardiomyocytes. Angiogenic inhibitors, including endostatin and angiostatin, inhibited endothelial cell differentiation and diminished cardiomyogenesis in ES cells. Generation of functional cardiomyocytes and the expression of cardiac-specific genes were significantly enhanced by co-culture of ES cells with human endothelial cells. Furthermore, the defects of cardiomyocyte differentiation in EphB4-deficient ES cells were rescued by human endothelial cells. For the first time, our study demonstrated that endothelial cells play an essential role in facilitating cardiomyocyte differentiation from pluripotent stem cells. EphB4 signaling is a critical component of the endothelial niche to regulate regeneration of cardiomyocytes.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Células Endoteliais/fisiologia , Miócitos Cardíacos/fisiologia , Inibidores da Angiogênese/farmacologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Efrina-B2/genética , Efrina-B2/metabolismo , Humanos , Camundongos , Camundongos Knockout , Miócitos Cardíacos/citologia , Receptor EphB4/genética , Receptor EphB4/metabolismo , Transdução de Sinais
12.
Prostate ; 70(16): 1768-77, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20564361

RESUMO

BACKGROUND: Slug is a transcription factor of the Snail/Slug zinc-finger family and is implicated in metastasis of tumors, but its role in cell proliferation of prostate cancers is unclear. METHODS: Expression level of Slug and other genes was examined by Western blot, RT-PCR, and QPCR analyses. The forced expression of Slug was mediated by retroviruses and adenoviruses. Slug was downregulated by shRNA. Cell growth was measured by the MTT assay and the quick cell proliferation assay. RESULTS: Here, we demonstrated that Slug expression is elevated in mouse prostate tumors, and human prostate cancer cell lines LNCaP, PC-3, and 22RV1. Forced expression of Slug-inhibited proliferation of prostate cancer cells PC-3 and DU-145. Conversely, reduced expression of Slug by shRNA promoted growth of PC-3 cancer cells. Consistent with these data, we found that forced expression of Slug in prostate cancer cells led to G1 cell-cycle arrest. Furthermore, ectopic expression of Slug decreased cyclin D1 expression in both PC-3 and DU-145 cells, and knockdown of Slug by shRNA upregulated cyclin D1 expression in these cancer cells. In addition, we demonstrated that ectopic expression of cyclin D1 relieved Slug-mediated inhibition of proliferation of prostate cancer cells. CONCLUSIONS: We provide the first compelling evidence that Slug is a negative regulator of proliferation of prostate cancer cells. Our findings in this study are distinct from the previously reported role of Slug as a promoter for tumor metastasis, and suggest that Slug is a prognostic marker and potential therapeutic target.


Assuntos
Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Fatores de Transcrição/genética , Animais , Western Blotting , Ciclo Celular , Divisão Celular , Galinhas/imunologia , Primers do DNA , Humanos , Masculino , Camundongos , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo
13.
J Clin Invest ; 130(6): 2992-3004, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32365055

RESUMO

De novo lipogenesis is tightly regulated by insulin and nutritional signals to maintain metabolic homeostasis. Excessive lipogenesis induces lipotoxicity, leading to nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes. Genetic lipogenic programs have been extensively investigated, but epigenetic regulation of lipogenesis is poorly understood. Here, we identified Slug as an important epigenetic regulator of lipogenesis. Hepatic Slug levels were markedly upregulated in mice by either feeding or insulin treatment. In primary hepatocytes, insulin stimulation increased Slug expression, stability, and interactions with epigenetic enzyme lysine-specific demethylase-1 (Lsd1). Slug bound to the fatty acid synthase (Fasn) promoter where Slug-associated Lsd1 catalyzed H3K9 demethylation, thereby stimulating Fasn expression and lipogenesis. Ablation of Slug blunted insulin-stimulated lipogenesis. Conversely, overexpression of Slug, but not a Lsd1 binding-defective Slug mutant, stimulated Fasn expression and lipogenesis. Lsd1 inhibitor treatment also blocked Slug-stimulated lipogenesis. Remarkably, hepatocyte-specific deletion of Slug inhibited the hepatic lipogenic program and protected against obesity-associated NAFLD, insulin resistance, and glucose intolerance in mice. Conversely, liver-restricted overexpression of Slug, but not the Lsd1 binding-defective Slug mutant, had the opposite effects. These results unveil an insulin/Slug/Lsd1/H3K9 demethylation lipogenic pathway that promotes NAFLD and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Epigênese Genética , Lipogênese , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fatores de Transcrição da Família Snail/biossíntese , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Deleção de Genes , Hepatócitos , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Fatores de Transcrição da Família Snail/genética
14.
Leukemia ; 34(2): 380-390, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31492896

RESUMO

Leukemia stem cells (LSCs) are the rare populations of acute myeloid leukemia (AML) cells that are able to initiate, maintain, and propagate AML. Targeting LSCs is a promising approach for preventing AML relapse and improving long-term outcomes. While Slug, a zinc-finger transcription repressor, negatively regulates the self-renewal of normal hematopoietic stem cells, its functions in AML are still unknown. We report here that Slug promotes leukemogenesis and its loss impairs LSC self-renewal and delays leukemia progression. Mechanistically, Slc13a3, a direct target of Slug in LSCs, restricts the self-renewal of LSCs and markedly prolongs recipient survival. Genetic or pharmacological inhibition of SLUG or forced expression of Slc13a3 suppresses the growth of human AML cells. In conclusion, our studies demonstrate that Slug differentially regulates self-renewal of LSCs and normal HSCs, and both Slug and Slc13a3 are potential therapeutic targets of LSCs.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição da Família Snail/metabolismo , Simportadores/metabolismo , Animais , Proliferação de Células/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Cell Death Dis ; 11(3): 180, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152291

RESUMO

Forkhead box M1 (FoxM1) transcriptional factor has a principal role in regulating cell proliferation, self-renewal, and tumorigenesis. However, whether FoxM1 regulates endogenous muscle development and regeneration remains unclear. Here we found that loss of FoxM1 in muscle satellite cells (SCs) resulted in muscle atrophy and defective muscle regeneration. FoxM1 functioned as a direct transcription activator of adenomatous polyposis coli (Apc), preventing hyperactivation of wnt/ß-catenin signaling during muscle regeneration. FoxM1 overexpression in SCs promoted myogenesis but impaired muscle regeneration as a result of spontaneous activation and exhaustion of SCs by transcriptional regulation of Cyclin B1 (Ccnb1). The E3 ubiquitin ligase Cdh1 (also termed Fzr1) was required for FoxM1 ubiquitylation and subsequent degradation. Loss of Cdh1 promoted quiescent SCs to enter into the cell cycle and the SC pool was depleted by serial muscle injuries. Haploinsufficiency of FoxM1 ameliorated muscle regeneration of Cdh1 knock-out mice. These data demonstrate that the Cdh1-FoxM1-Apc axis functions as a key regulator of muscle development and regeneration.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Proteína Forkhead Box M1/metabolismo , Desenvolvimento Muscular/genética , Animais , Humanos , Camundongos
16.
Nat Commun ; 10(1): 2568, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189923

RESUMO

Activation of the p16Ink4a-associated senescence pathway during aging breaks muscle homeostasis and causes degenerative muscle disease by irreversibly dampening satellite cell (SC) self-renewal capacity. Here, we report that the zinc-finger transcription factor Slug is highly expressed in quiescent SCs of mice and functions as a direct transcriptional repressor of p16Ink4a. Loss of Slug promotes derepression of p16Ink4a in SCs and accelerates the entry of SCs into a fully senescent state upon damage-induced stress. p16Ink4a depletion partially rescues defects in Slug-deficient SCs. Furthermore, reduced Slug expression is accompanied by p16Ink4a accumulation in aged SCs. Slug overexpression ameliorates aged muscle regeneration by enhancing SC self-renewal through active repression of p16Ink4a transcription. Our results identify a cell-autonomous mechanism underlying functional defects of SCs at advanced age. As p16Ink4a dysregulation is the chief cause for regenerative defects of human geriatric SCs, these findings highlight Slug as a potential therapeutic target for aging-associated degenerative muscle disease.


Assuntos
Autorrenovação Celular/genética , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Células Satélites de Músculo Esquelético/fisiologia , Fatores de Transcrição da Família Snail/metabolismo , Envelhecimento/fisiologia , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Fatores de Transcrição da Família Snail/genética
17.
Methods Mol Biol ; 1733: 255-263, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29435939

RESUMO

MicroRNAs are small 18-24 nt single-stranded noncoding RNA molecules involved in many biological processes, including stemness maintenance and cellular reprogramming. Current methods used in loss-of-function studies of microRNAs have several limitations. Here, we describe a new approach for dissecting miR-302/367 functions by transcription activator-like effectors (TALEs), which are natural effector proteins secreted by Xanthomonas and Ralstonia bacteria. Knockdown of the miR-302/367 cluster uses the Kruppel-associated box repressor domain fused with specific TALEs designed to bind the miR-302/367 cluster promoter. Knockout of the miR-302/367 cluster uses two pairs of TALE nucleases (TALENs) to delete the miR-302/367 cluster in human primary cells. Together, both TALE-based transcriptional repressor and TALENs are two promising approaches for loss-of-function studies of microRNA cluster in human primary cells.


Assuntos
Reprogramação Celular/genética , MicroRNAs/genética , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Fibroblastos/metabolismo , Deleção de Genes , Genes Reporter , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lentivirus/genética , Plasmídeos/genética , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Retroviridae/genética
18.
Stem Cells Transl Med ; 6(5): 1412-1423, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28244269

RESUMO

Muscle stem cells (MuSCs) exhibit robust myogenic potential in vivo, thus providing a promising curative treatment for muscle disorders. Ex vivo expansion of adult MuSCs is highly desired to achieve a therapeutic cell dose because of their scarcity in limited muscle biopsies. Sorting of pure MuSCs is generally required for all the current culture systems. Here we developed a soft three-dimensional (3D) salmon fibrin gel culture system that can selectively expand mouse MuSCs from bulk skeletal muscle preparations without cell sorting and faithfully maintain their regenerative capacity in culture. Our study established a novel platform for convenient ex vivo expansion of MuSCs, thus greatly advancing stem cell-based therapies for various muscle disorders. Stem Cells Translational Medicine 2017;6:1412-1423.


Assuntos
Fibrina/química , Géis/química , Fibras Musculares Esqueléticas/citologia , Células Satélites de Músculo Esquelético/citologia , Animais , Diferenciação Celular/fisiologia , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
19.
Mol Ther Nucleic Acids ; 7: 31-41, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28624206

RESUMO

Muscle stem cells (MuSCs) hold great therapeutic potential for muscle genetic disorders, such as Duchenne muscular dystrophy (DMD). The CRISP/Cas9-based genome editing is a promising technology for correcting genetic alterations in mutant genes. In this study, we used fibrin-gel culture system to selectively expand MuSCs from crude skeletal muscle cells of mdx mice, a mouse model of DMD. By CRISP/Cas9-based genome editing, we corrected the dystrophin mutation in expanded MuSCs and restored the skeletal muscle dystrophin expression upon transplantation in mdx mice. Our studies established a reliable and feasible platform for gene correction in MuSCs by genome editing, thus greatly advancing tissue stem cell-based therapies for DMD and other muscle disorders.

20.
Cell Stem Cell ; 19(3): 355-69, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27345836

RESUMO

Pluripotency is increasingly recognized as a spectrum of cell states defined by their growth conditions. Although naive and primed pluripotency states have been characterized molecularly, our understanding of events regulating state acquisition is wanting. Here, we performed comparative RNA sequencing of mouse embryonic stem cells (ESCs) and defined a pluripotent cell fate (PCF) gene signature associated with acquisition of naive and primed pluripotency. We identify Zfp281 as a key transcriptional regulator for primed pluripotency that also functions as a barrier toward achieving naive pluripotency in both mouse and human ESCs. Mechanistically, Zfp281 interacts with Tet1, but not Tet2, and its direct transcriptional target, miR-302/367, to negatively regulate Tet2 expression to establish and maintain primed pluripotency. Conversely, ectopic Tet2 alone, but not Tet1, efficiently reprograms primed cells toward naive pluripotency. Our study reveals a molecular circuitry in which opposing functions of Tet1 and Tet2 control acquisition of alternative pluripotent states.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Linhagem da Célula/genética , Dioxigenases , Epigênese Genética , Perfilação da Expressão Gênica , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Pluripotentes/citologia , Interferência de RNA , Transcrição Gênica
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