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1.
J Cell Mol Med ; 22(6): 3246-3258, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29602239

RESUMO

Toll-like receptor 4 (TLR4) which acts as a receptor for lipopolysaccharide (LPS) has been reported to be involved in carcinogenesis. However, the regulatory mechanism of it has not been elucidated. Herein, we demonstrate that TLR4 promotes the malignant growth of liver cancer stem cells. Mechanistically, TLR4 promotes the expression of histone-lysine N-methyltransferase (SUV39 h2) and increases the formation of trimethyl histone H3 lysine 9-heterochromatin protein 1-telomere repeat binding factor 2 (H3K9me3-HP1-TRF2) complex at the telomeric locus under mediation by long non coding RNA urothelial cancer-associated 1 (CUDR). At the telomeric locus, this complex promotes binding of POT1, pPOT1, Exo1, pExo1, SNM1B and pSNM1B but prevents binding of CST/AAF to telomere, thus controlling telomere and maintaining telomere length. Furthermore, TLR4 enhances interaction between HP1α and DNA methyltransferase (DNMT3b), which limits RNA polymerase II deposition on the telomeric repeat-containing RNA (TERRA) promoter region and its elongation, thus inhibiting transcription of TERRA. Ultimately, TLR4 enhances the telomerase activity by reducing the interplay between telomerase reverse transcriptase catalytic subunit (TERT) and TERRA. More importantly, our results reveal that tri-complexes of HP1 isoforms (α, ß and γ) are required for the oncogenic action of TLR4. This study elucidates a novel protection mechanism of TLR4 in liver cancer stem cells and suggests that TLR4 can be used as a novel therapeutic target for liver cancer.


Assuntos
Proteínas Cromossômicas não Histona/genética , Neoplasias Hepáticas/genética , Telomerase/genética , Receptor 4 Toll-Like/genética , Linhagem Celular Tumoral , Homólogo 5 da Proteína Cromobox , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Isoformas de Proteínas/genética , RNA Longo não Codificante/genética , Telômero/genética , Homeostase do Telômero/genética , Proteína 2 de Ligação a Repetições Teloméricas/genética , Fatores de Transcrição/genética , DNA Metiltransferase 3B
2.
Inorg Chem ; 53(17): 9052-7, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25116434

RESUMO

Two new oxalate-bridged Gd(III) coordination polymers, namely, (choline)[Gd(C2O4)(H2O)3Cl]Cl·H2O (1) and [Gd(C2O4)(H2O)3Cl] (2), were first obtained ionothermally by using a deep eutectic solvent (DES). The magnetic studies and heat capacity measurements reveal that the two-dimensional Gd(III)-based coordination polymer of 2 has the higher magnetic density and exhibits a larger cryogenic magnetocaloric effect (MCE) (ΔS(m) = 48 J kg(-1) K(-1) for ΔH = 7 T at 2.2 K).

4.
Inorg Chem ; 51(9): 5099-109, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22486154

RESUMO

A series of mononuclear gold(I) acetylide complexes with urea moiety, R'(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(4)-4-R (R' = cyclohexyl, R = NO(2) (2a), CF(3) (2b), Cl (2c), H (2d), CH(3) (2e), (t)Bu (2f), OCH(3) (2g); R' = phenyl, R = NO(2) (3a), OCH(3) (3b); R' = 4-methoxyphenyl, R = H (4a), OCH(3) (4b)), have been synthesized and characterized. The crystal structures of Ph(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(4)-4-NO(2) (3a) and (4-CH(3)OC(6)H(4))(3)PAuC≡CC(6)H(4)-4-NHC(O)NHC(6)H(5) (4a) have been determined by X-ray diffraction. Complexes 2a-2g, 3b, and 4a-4b show intense luminescence both in the solid state and in degassed THF solution at 298 K. Anion binding properties of complexes 2a-2g, 3a-3b, and 4a-4b have been studied by UV-vis and (1)H NMR titration experiments. In general, the log K values of 2a-2g with the same anion in THF depend on the substituent R on the acetylide ligand of 2a-2g: R = NO(2) (2a) > CF(3) (2b) ≥ Cl (2c) > H (2d) > CH(3) (2e) ≈ (t)Bu (2f) ≥ OCH(3) (2g). Complex 2a with NO(2) group shows the dramatic color change toward F(-) in DMSO, which provides an access of naked eye detection of F(-).


Assuntos
Técnicas de Química Analítica/instrumentação , Técnicas de Química Sintética , Ouro/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Ureia/química , Cristalografia por Raios X , Dimetil Sulfóxido/química
5.
ACS Appl Mater Interfaces ; 14(30): 34161-34170, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34333970

RESUMO

Defect passivation is a key strategy to prepare high-performance perovskite solar cells (PVSCs). Even though abundant passivation molecules have been applied, the absence of detailed researches with regard to different functional groups in polymer additives may inevitably impede the establishment of passivation molecules selection rules. In this work, three passivation molecules including poly(vinyl alcohol) (PVA), polymethyl acrylate (PMA), and poly(acrylic acid) (PAA) are employed to systematically analyze the passivation effect from hydroxyl, carbonyl, and carboxyl groups. In general, PVA (-OH) can form hydrogen bonds with perovskite and PMA (-C═O) can complex with uncoordinated Pb2+. Specifically, PAA (-COOH) can interact selectively with MA+ and I- ions via hydrogen bonding and complex with uncoordinated Pb2+ to passivate defects more effectively. Hence, the PAA-incorporated PVSCs based on MAPbI3 achieve the champion power conversion efficiency (PCE) of 20.29% with open-circuit voltage up to 1.13 V. In addition, PAA cross-linking perovskite grains can relieve mechanical stress, as well as occupy the major channels to suppress ion migration and water/oxygen erosion. The corresponding unencapsulated devices demonstrate a superior light soaking stability, retaining more than 80% of the original PCE under one sun illumination for 1000 h.

6.
Chemistry ; 17(8): 2458-66, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21319238

RESUMO

A family of linear Dy(3) and Tb(3) clusters have been facilely synthesized from the reactions of DyCl(3), the polydentate 3-methyloxysalicylaldoxime (MeOsaloxH(2) ) ligand with auxiliary monoanionic ligands, such as trichloroacetate, NO(3)(-), OH(-), and Cl(-). Complexes 1-5 contain a nearly linear Ln(3) core, with similar Ln···Ln distances (3.6901(4)-3.7304(3) Å for the Dy(3) species, and 3.7273(3)-3.7485(5) Å for the Tb(3) species) and Ln···Ln···Ln angles of 157.036(8)-159.026(15)° for the Dy(3) species and 157.156(8)-160.926(15)° for the Tb(3) species. All three Ln centers are bridged by the two doubly-deprotonated [MeOsalox](2-) ligands and two of the four [MeOsaloxH](-) ligands through the N,O-η(2)-oximato groups and the phenoxo oxygen atoms (Dy-O-Dy angles=102.28(16)-106.85(13)°; Tb-O-Tb angles=102.00(11)-106.62(11)°). The remaining two [MeOsaloxH](-) ligands each chelate an outer Ln(III) center through their phenoxo oxygen and oxime nitrogen atoms. Magnetic studies reveal that both Dy(3) and Tb(3) clusters exhibit significant ferromagnetic interactions and that the Dy(3) species behave as single-molecule magnets, expanding upon the recent reports of the pure 4f type SMMs.


Assuntos
Compostos de Ferro/síntese química , Elementos da Série dos Lantanídeos/síntese química , Magnetismo , Cristalografia por Raios X , Compostos de Ferro/química , Elementos da Série dos Lantanídeos/química , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Termodinâmica
7.
ACS Appl Mater Interfaces ; 13(13): 15420-15428, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33759500

RESUMO

Tin-based perovskite solar cells (PVSCs) are regarded as the most promising alternative among lead-free PVSCs. However, the rapid crystallization for tin-based perovskite tends to cause inferior film morphology and abundant defect states, which make poor photovoltaic performance. Here, 1-butyl-3-methylimidazolium bromide (BMIBr) ionic liquids (ILs) with strong polarity and a low melting point are first employed to produce the Ostwald ripening effect and obtain high-quality tin-based perovskite films with a large grain size. Meanwhile, the non-radiative recombination ascribed from defect states can also be effectively reduced for BMIBr-treated perovskite films. Consequently, a photoelectric conversion efficiency (PCE) of 10.09% for inverted tin-based PVSCs is attained by the Ostwald ripening effect. Moreover, the unencapsulated devices with BMIBr retain near 85% of the original PCE in a N2 glovebox beyond 1200 h and about 40% of the original PCE after exposure to air for 48 h.

8.
ACS Appl Mater Interfaces ; 12(12): 14049-14056, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32129060

RESUMO

Tin-based perovskite solar cells (PVSCs) have emerged as the most promising lead-free perovskite materials owing to their superior optoelectronic properties. However, the deficiency of accurate control of the tin-based perovskite crystallization process increases the possibility of unexpected perovskite film morphology and defects, resulting in inferior power conversion efficiency (PCE). Meanwhile, the poor environmental stability of tin-based perovskite films hinders its further development. In this work, a unique polymer [poly(ethylene-co-vinyl acetate) (EVA)] is introduced into anti-solvent during spin coating of formamidinium tin tri-iodide (FASnI3) precursor solution. The C═O groups contained in EVA have a powerful Lewis acid-base complexation with uncoordinated tin atoms in perovskite grains, which can greatly improve the grain size, optimize the grain orientation, and decrease the surface defects of FASnI3 films. This strategy offers an impressive PCE of 7.72% with favorable reproducibility. More importantly, the PVSC devices based on FASnI3-EVA absorbers have a self-encapsulation effect, which exhibits distinguished moisture and oxygen barrier property, thereby retaining 62.4% of the original efficiency value after aging for 48 h in the air with a humidity of 60%. Such a convenient strategy provides a new inspiration for the establishment of stable and high-performance tin-based PVSCs.

9.
Chem Commun (Camb) ; 56(28): 4007-4010, 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32159204

RESUMO

The N and O atoms in the bidentate ligand 8-hydroxyquinoline (8-HQ) can simultaneously coordinate with Sn2+, which greatly inhibits the oxidation of Sn2+. The formation of complexes improves the quality of FASnI3 films and reduces defect states, resulting in improvements in the efficiency and stability of FASnI3-based perovskite solar cells.

10.
Adv Mater ; 32(26): e2000617, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32449256

RESUMO

Sequential deposition is certified as an effective technology to obtain high-performance perovskite solar cells (PVSCs), which can be derivatized into large-scale industrial production. However, dense lead iodide (PbI2 ) causes incomplete reaction and unsatisfactory solution utilization of perovskite in planar PVSCs without mesoporous titanium dioxide as a support. Here, a novel autonomously longitudinal scaffold constructed by the interspersion of in situ self-polymerized methyl methacrylate (sMMA) in PbI2 is introduced to fabricate efficient PVSCs with excellent flexural endurance and environmental adaptability. By this strategy perovskite solution can be confined within an organic scaffold with vertical crystal growth promoted, effectively inhibiting exciton accumulation and recombination at grain boundaries. Additionally, sMMA cross-linked perovskite network can release mechanical stress and occupy the main channels for ion migration and water/oxygen permeation to significantly improve operational stability, which opens up a new strategy for the commercial development of large-area PVSCs in flexible electronics.

11.
Chem Commun (Camb) ; (47): 6348-50, 2008 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-19048151

RESUMO

Three microporous Ln-Co-pyta heterometallic compounds [Ln4Co3(pyta)6(H2O)9].5H2O (Ln = Sm (1), Eu (2), Gd (3); H3pyta = 2,4,6-pyridinetricarboxylic acid) have interesting selective adsorption abilities towards H2/N2 and CO2/N2 because of size-selective effects; magnetic analysis reveals that has a ferromagnetic behavior.


Assuntos
Gases/química , Magnetismo , Adsorção , Modelos Moleculares , Conformação Molecular , Porosidade
12.
Cell Death Dis ; 9(3): 253, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29449541

RESUMO

Maternally expressed gene 3 (MEG3) encodes an lncRNA which is suggested to function as a tumor suppressor and has been showed to involve in a variety of cancers. Herein, our findings demonstrate that MEG3 inhibits the malignant progression of liver cancer cells in vitro and in vivo. Mechanistically, MEG3 promotes the expression and maturition of miR122 which targets PKM2. Therefore, MEG3 decreases the expression and nuclear location of PKM2 dependent on miR122. Furthermore, MEG3 also inhibits CyclinD1 and C-Myc via PKM2 in liver cancer cells. On the other hand, MEG3 promotes ß-catenin degradation through ubiquitin-proteasome system dependent on PTEN. Strikingly, MEG3 inhibits ß-catenin activity through PKM2 reduction and PTEN increase. Significantly, we also found that excessive ß-catenin abrogated the effect of MEG3 in liver cancer. In conclusion, our study for the first time demonstrates that MEG3 acts as a tumor suppressor by negatively regulating the activity of the PKM2 and ß-catenin signaling pathway in hepatocarcinogenesis and could provide potential therapeutic targets for the treatment of liver cancer.


Assuntos
Proteínas de Transporte/metabolismo , Proliferação de Células , Neoplasias Hepáticas/enzimologia , Proteínas de Membrana/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , RNA Longo não Codificante/metabolismo , Hormônios Tireóideos/metabolismo , beta Catenina/metabolismo , Animais , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Estabilidade Enzimática , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , PTEN Fosfo-Hidrolase/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , RNA Longo não Codificante/genética , Transdução de Sinais , Hormônios Tireóideos/genética , Carga Tumoral , beta Catenina/genética , Proteínas de Ligação a Hormônio da Tireoide
13.
Mol Ther Nucleic Acids ; 11: 367-381, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29858072

RESUMO

Inflammatory and autophagy-related gene P62 is highly expressed in most human tumor tissues. Herein, we demonstrate that P62 promotes human mesenchymal stem cells' malignant transformation via the cascade of P62-tumor necrosis factor alpha (TNF-α)-CUDR-CTCF-insulin growth factor II (IGFII)-H-Ras signaling. Mechanistically, we reveal P62 enhances IGFII transcriptional activity through forming IGFII promoter-enhancer chromatin loop and increasing METTL3 occupancy on IGFII 3' UTR and enhances H-Ras overexpression by harboring inflammation-related factors, e.g., TNFR1, CLYD, EGR1, NFκB, TLR4, and PPARγ. Furthermore, the P62 cooperates with TNF-α to promote malignant transformation of mesenchymal stem cells. These findings, for the first time, provide insight into the positive role that P62 plays in malignant transformation of mesenchymal stem cells and reveal a novel link between P62 and the inflammation factors in mesenchymal stem cells.

14.
Mol Ther Nucleic Acids ; 11: 494-507, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29858084

RESUMO

MicroRNAs are known to be involved in carcinogenesis. Recently, microRNA-372 (miR372) has been proven to play a substantial role in several human cancers, but its functions in liver cancer remain unclear. Herein, our results demonstrate that miR372 accelerates growth of liver cancer cells in vitro and in vivo. Mechanistically, miR372 enhances expression of Y-box-binding protein 1 (YB-1) by targeting for phosphatase and tensin homolog (PTEN) directly and consequently promotes phosphorylation of YB-1 via HULC looping dependent on ERK1/2 and PTEN. In particular, HULC knockdown or PTEN overexpression abrogated this miR372 action. Moreover, miR372 inhibits the degradation of ß-catenin dependent on phosphorylation of YB-1 and then enhances the expression and activity of pyruvate kinase M2 isoform (PKM2) by ß-catenin-LEF/TCF4 pathway. Furthermore, the loading of LEF/TCF4 on PKM2 promoter region was significantly increased in miR372 overexpressing Hep3B, and thus, glycolytic proton efflux rate (glycoPER) was significantly increased in rLV-miR372 group compared to the rLV group. Moreover, ß-catenin knockdown abrogates this function of miR372. Ultimately, miR372 promotes the expression of erbB-2 through PKM2-pH3T11-acetylation on histone H3 lysine 9 (H3K9Ac) pathway. Of significance, both YB-1 knockdown and erbB-2 knockdown abrogate oncogenic action of miR372. Our observations suggest that miR372 promotes liver cancer cell cycle progress by activating cyclin-dependent kinase 2 (CDK2)-cyclin E-P21/Cip1 complex through miR372-YB-1-ß-catenin-LEF/TCF4-PKM2-erbB-2 axis. This study elucidates a novel mechanism for miR372 in liver cancer cells and suggests that miR372 can be used as a novel therapeutic target of liver cancer.

15.
Oncotarget ; 8(30): 49093-49109, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28467776

RESUMO

Changes in histone lysine methylation status have been observed during cancer formation. JMJD2A protein is a demethylase that is overexpressed in several tumors. Herein, our results demonstrate that JMJD2A accelerates malignant progression of liver cancer cells in vitro and in vivo. Mechanistically, JMJD2A promoted the expression and mature of pre-miR372 epigenetically. Notably, miR372 blocks the editing of 13th exon-introns-14th exon and forms a novel transcript( JMJD2AΔ) of JMJD2A. In particular, JMJD2A inhibited P21(WAF1/Cip1) expression by decreasing H3K9me3 dependent on JMJD2AΔ. Thereby, JMJD2A could enhance Pim1 transcription by suppressing P21(WAF1/Cip1). Furthermore, through increasing the expression of Pim1, JMJD2A could facilitate the interaction among pRB, CDK2 and CyclinE which prompts the transcription and translation of oncogenic C-myc. Strikingly, JMJD2A may trigger the demethylation of Pim1. On the other hand, Pim1 knockdown and P21(WAF1/Cip1) overexpression fully abrogated the oncogenic function of JMJD2A. Our observations suggest that JMJD2A promotes liver cancer cell cycle progress through JMJD2A-miR372-JMJD2AΔ-P21WAF1/Cip1-Pim1-pRB-CDK2-CyclinE-C-myc axis. This study elucidates a novel mechanism for JMJD2A in liver cancer cells and suggests that JMJD2A can be used as a novel therapeutic targets of liver cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , Animais , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Epigênese Genética , Proteínas Fúngicas/metabolismo , Xenoenxertos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Regiões Promotoras Genéticas , Proteínas de Ligação a Retinoblastoma/metabolismo , Transdução de Sinais , Ativação Transcricional , Ubiquitina-Proteína Ligases/metabolismo
16.
Chem Commun (Camb) ; (19): 2021-3, 2006 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-16767262

RESUMO

Two new isostructural coordination polymers with novel anionic metal-organic frameworks are synthesized under microwave conditions using an ionic liquid EMIm-Br as solvent and template.

17.
Oncotarget ; 7(41): 66525-66539, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27167190

RESUMO

P53 is frequently mutated in human tumors as a novel gain-of-function to promote tumor development. Although dimeric (M340Q/L344R) influences on tetramerisation on site-specific post-translational modifications of p53, it is not clear how dimeric (M340Q/L344R) plays a role during hepatocarcinogenesis. Herein, we reveal that P53 (N340Q/L344R) promotes hepatocarcinogenesis through upregulation of PKM2. Mechanistically, P53 (N340Q/L344R) forms complex with CUDR and the complex binds to the promoter regions of PKM2 which enhances the expression, phosphorylation of PKM2 and its polymer formation. Thereby, the polymer PKM2 (tetramer) binds to the eleventh threonine on histone H3 that increases the phosphorylation of the eleventh threonine on histone H3 (pH3T11). Furthermore, pH3T11 blocks HDAC3 binding to H3K9Ac that prevents H3K9Ac from deacetylation and stabilizes the H3K9Ac modification. On the other hand, it also decreased tri-methylation of histone H3 on the ninth lysine (H3K9me3) and increases one methylation of histone H3 on the ninth lysine (H3K9me1). Moreover, the combination of H3K9me1 and HP1 α forms more H3K9me3-HP1α complex which binds to the promoter region of Pim1, enhancing the expression of Pim1 that enhances the expression of TERT, oncogenic lncRNA HOTAIR and reduces the TERRA expression. Ultimately, P53 (N340Q/L344R) accerlerates the growth of liver cancer cells Hep3B by activating telomerase and prolonging telomere through the cascade of P53 (N340Q/L344R)-CUDR-PKM2-pH3T11- (H3K9me1-HP1α)-Pim1- (TERT-HOTAIR-TERRA). Understanding the novel functions of P53 (N340Q/L344R) will help in the development of new liver cancer therapeutic approaches that may be useful in a broad range of cancer types.


Assuntos
Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas c-pim-1/biossíntese , RNA Longo não Codificante/genética , Hormônios Tireóideos/genética , Proteína Supressora de Tumor p53/genética , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Homólogo 5 da Proteína Cromobox , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Proteínas Proto-Oncogênicas c-pim-1/genética , Regulação para Cima , Proteínas de Ligação a Hormônio da Tireoide
18.
Sci Rep ; 6: 36045, 2016 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-27782152

RESUMO

The dysregulation of lncRNAs has increasingly been linked to many human diseases, especially in cancers. Our results demonstrate HULC, MALAT1 and TRF2 are highly expressed in human hepatocellular carcinoma tissues, and HULC plus MALAT1 overexpression drastically promotes the growth of liver cancer stem cells. Mechanistically, both HULC and MALAT1 overexpression enhanced RNA polII, P300, CREPT to load on the promoter region of telomere repeat-binding factor 2(TRF2), triggering the overexpression, phosphorylation and SUMOylation of TRF2. Strikingly, the excessive TRF2 interacts with HULC or MALAT1 to form the complex that loads on the telomeric region, replacing the CST/AAF and recruiting POT1, pPOT1, ExoI, SNM1B, HP1 α. Accordingly, the telomere is greatly protected and enlonged. Furthermore, the excessive HULC plus MALAT1 reduced the methylation of the TERC promoter dependent on TRF2, increasing the TERC expression that causes the increase of interplay between TRET and TERC. Ultimately, the interaction between RFC and PCNA or between CDK2 and CyclinE, the telomerase activity and the microsatellite instability (MSI) are significantly increased in the liver cancer stem cells. Our demonstrations suggest that haploinsufficiency of HULC/MALAT1 plays an important role in malignant growth of liver cancer stem cell.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/biossíntese , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/biossíntese , RNA Neoplásico/biossíntese , Proteína 2 de Ligação a Repetições Teloméricas/biossíntese , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Proteína 2 de Ligação a Repetições Teloméricas/genética
19.
Oncotarget ; 7(31): 50131-50149, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27367027

RESUMO

Cancer stem cells are associated with tumor recurrence. IKK is a protein kinase that is composed of IKKα, IKKß, IKKγ. Herein, we demonstrate that IKKα plus IKKß promoted and IKKγ inhibited liver cancer stem cell growth in vitro and in vivo. Mechanistically, IKKα plus IKKß enhanced and IKKγ inhibited the interplay among HP1α, HP1ß and HP1γ that competes for the interaction among HP1α, SUZ12, HEZ2. Therefore, IKKα plus IKKß inhibited and IKKγ enhanced the activity of H3K27 methyltransferase SUZ12 and EZH2, which methylates H3K27 immediately sites on HOTAIR promoter region. Therefore, IKKα plus IKKß increased and IKKγ decreased the HOTAIR expression. Strikingly, IKKα plus IKKß decreases and IKKγ increases the HP1α interplays with DNA methyltransferase DNMT3b, which increases or decreases TERRA promoter DNA methylation. Thus IKKα plus IKKß reduces and IKKγ increases to recruit TRF1 and RNA polymerase II deposition and elongation on the TERRA promoter locus, which increases or decreases TERRA expression. Furthermore, IKKα plus IKKß decreases/increases and IKKγ increases/decreases the interplay between TERT and TRRRA/between TERT and TREC. Ultimately, IKKα plus IKKß increases and IKKγ decreases the telomerase activity. On the other hand, at the telomere locus, IKKα plus IKKß increases/drcreases and IKKγ decreases/increases TRF2, POT1, pPOT1, Exo1, pExo1, SNM1B, pSNM1B/CST-AAF binding, which keep active telomere regulatory genes and poised for telomere length. Strikingly, HOTAIR is required for IKKα plus IKKß and IKKγ to control telomerase activity and telomere length. These observations suggest that HOTAIR operates the action of IKKα, IKKß, IKKγ in liver cancer stem cells. This study provides a novel basis to elucidate the oncogenic action of IKKα, IKKß, IKKγ and prompts that IKKα, IKKß, IKKγ cooperate to HOTAR to be used as a novel therapeutic targets for liver cancer.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Quinase I-kappa B/metabolismo , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/metabolismo , Telômero/ultraestrutura , Animais , Movimento Celular , Homólogo 5 da Proteína Cromobox , Metilação de DNA , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Inflamação , Camundongos , Camundongos Endogâmicos BALB C , Recidiva Local de Neoplasia , Transplante de Neoplasias , Transdução de Sinais
20.
Sci Rep ; 6: 36843, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27833137

RESUMO

Inflammatory cytokines and lncRNAs are closely associated with tumorigenesis. Herein, we reveal inflammatory cytokines IL6 cooperates with long noncoding RNA CUDR to trigger the malignant transformation of human embryonic stem cells-derived hepatocyte-like stem cells. Mechanistically, IL6 cooperates with CUDR to cause MELLT3 to interact with SUV39h1 mRNA3'UTR and promote SUV39h1 expression. Moreover, the excessive SUV39h1 also increases tri-methylation of histone H3 on nineth lysine (H3K9me3). Intriguingly, under inflammatory conditions, H3K9me3 promotes the excessive expression and phosphorylation of NF-κB, and in turn, phorsphorylated NF-κB promotes the expression and phosphorylation of Stat3. Furthermore, that the phosphorylated Stat3 loads onto the promoter region of miRs and lncRNAs. Ultimately, the abnormal expression of miRs and lncRNAs increased telomerase activity, telomere length and microsatellite instability (MSI), leading to malignant transformation of hepatocyte-like stem cells.


Assuntos
Transformação Celular Neoplásica , Interleucina-6/fisiologia , Neoplasias Hepáticas Experimentais/patologia , RNA Longo não Codificante/fisiologia , Animais , Linhagem Celular , Regulação Neoplásica da Expressão Gênica , Hepatócitos/patologia , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Fígado/metabolismo , Fígado/patologia , Metiltransferases/metabolismo , Camundongos Endogâmicos BALB C , MicroRNAs/metabolismo , Instabilidade de Microssatélites , NF-kappa B/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Células-Tronco/patologia , Telomerase/metabolismo , Homeostase do Telômero
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