Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.424
Filtrar
1.
DNA Cell Biol ; 38(7): 651-659, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31140859

RESUMO

Breast cancer is the leading cause of death in women. Although numerous clinical regimens are used to treat breast cancer and manifest satisfied efficacy, drug resistance is emerging as the major obstacle to their long-term use. It is critically necessary to decipher the molecular mechanism underlying this process to obtain improved and long-term use of each regimen. In the present study, we showed the negative relationship between EZH2 and chemoresistance to taxol in breast cancer cells. EZH2 interference was capable of decreasing while overexpression increasing apoptosis of breast cancer cells challenged with taxol. Meanwhile, p21, the inhibitor of cell cycle entry, interference upregulated, while overexpression downregulated apoptosis induced by taxol. Mechanistically, EZH2 was recruited to the promoter of p21 accompanied with H3K27me3 enrichment and transcription silencing. Collectively, EZH2 attenuates chemoresistance of breast cancer cells to taxol by dampening p21 epigenetically.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Neoplasias da Mama/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Paclitaxel/toxicidade , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Humanos , Células MCF-7
2.
Mol Med Rep ; 19(6): 5097-5104, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059057

RESUMO

Numerous studies have demonstrated the association between senescence and cancer. However, the molecular mechanism regulating senescence in ovarian cancer remains unknown. In the present study, the protein expression level of calbindin 1 (CALB1) in ovarian cancer was examined using western blot and immunohistochemistry. The function of CALB1 in ovarian cancer cells was examined using MTT assay, anchorage­independent growth assay and senescence assay. The molecular mechanisms underlying CALB1 function were investigated using immunoprecipitation and pull­down assays. In the present study, the expression of CALB1 was found to be increased in ovarian cancer. Overexpression of CALB1 promoted the proliferation and colony formation of ovarian cancer cells and inhibited senescence by modulating the expression levels of p21 and p27. Knockdown of CALB1 inhibited the proliferation and colony formation of ovarian cancer cells. Mechanistically, co­immunoprecipitation assays revealed that CALB1 interacts with MDM2 proto­oncogene (MDM2) and promoted the interaction between p53 and MDM2. Collectively, the present study suggested that CALB1 may act as an oncogene in ovarian cancer by inhibiting the p53 pathway.


Assuntos
Calbindina 1/metabolismo , Senescência Celular , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Calbindina 1/antagonistas & inibidores , Calbindina 1/genética , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo
3.
Mol Med Rep ; 19(6): 5195-5202, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059098

RESUMO

MicroRNAs (miRNAs) are considered to be critical mediators of gene expression with respect to tumor progression, although their role in ischemia­induced angiogenesis is poorly characterized, including in peripheral arterial disease (PAD). Furthermore, the underlying mechanism of action of specific miRNAs in PAD remains unknown. Reverse transcription­quantitative polymerase chain reaction analysis revealed that microRNA­93 (miR­93) was significantly upregulated in patients with PAD and in the EA.hy926 endothelial cells in response to hypoxia. Additionally, miRNA (miR)­93 promoted angiogenesis by enhancing proliferation, migration and tube formation. Cyclin dependent kinase inhibitor 1A (CDKN1A), verified as a potential target gene of miR­93, was inhibited by overexpressed miR­93 at the protein and mRNA expression levels. Furthermore, a hind­limb ischemia model served to evaluate the role of miR­93 in angiogenesis in vivo, and the results demonstrated that miR­93 overexpression enhanced capillary density and perfusion recovery from hind­limb ischemia. Taken together, miR­93 was indicated to be a promising target for pharmacological regulation to promote angiogenesis, and the miR­93/CDKN1A pathway may function as a novel therapeutic approach in PAD.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/metabolismo , MicroRNAs/metabolismo , Neovascularização Fisiológica , Doença Arterial Periférica/patologia , Regiões 3' não Traduzidas , Idoso , Animais , Hipóxia Celular , Linhagem Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/química , Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Membro Posterior/patologia , Humanos , Isquemia/metabolismo , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/química , MicroRNAs/genética , Pessoa de Meia-Idade , Doença Arterial Periférica/sangue , Doença Arterial Periférica/genética
4.
Int J Mol Sci ; 20(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035388

RESUMO

Transactivation of p21 (cyclin-dependent kinase inhibitor 1A, CDKN1A) is closely related to the recruitment of transcription cofactors at the p53 responsive elements (p53REs) in its promoter region. Human chromatin remodeling enzyme INO80 can be recruited to the p53REs of p21 promoter and negatively regulates p21. As one of the key subunits of the INO80 complex, YY1 has also been confirmed to bind to the p53RE sites of p21 promoter. Importantly, YY1 was recently reported to be bound and stabilized by BCCIP (BRCA2 and CDKN1A-interacting protein). Therefore, we hypothesized that the YY1/BCCIP complex plays an important role in regulating the transactivation of p21. Here we present evidence that the YY1/BCCIP complex coordinatively regulates p53RE-mediated p21 transactivation. We first confirmed the cross-interaction between YY1, BCCIP, and p53, suggesting an intrinsic link between three proteins in the regulation of p21 transcription. In dual luciferase assays, YY1 inhibited p53RE-mediated luciferase activity, whereas BCCIP revealed the opposite effect. More interestingly, the region 146-270 amino acids of YY1, which bound to BCCIP, increased p53-mediated luciferase activity, indicating the complexity of the YY1/BCCIP complex in co-regulating p21 transcription. Further in-depth research confirmed the co-occupancy of YY1/BCCIP with p53 at the p53RE-proximal region of p21. Lentiviral-mediated knockdown of BCCIP inhibited the recruitment of p53 and YY1 at the p53RE proximal region of p21; however, this phenomenon was reversed by expressing exogenous YY1, suggesting the collaborative regulation of YY1/BCCIP complex in p53RE-mediated p21 transcription. These data provide new insights into the transcriptional regulation of p21 by the YY1/BCCIP complex.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fator de Transcrição YY1/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Células HCT116 , Humanos , Proteínas Nucleares/genética , Ativação Transcricional/genética , Ativação Transcricional/fisiologia , Fator de Transcrição YY1/genética
5.
Nat Commun ; 10(1): 1969, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036808

RESUMO

Long noncoding RNAs (lncRNAs) are emerging as regulators of fundamental biological processes. Here we report on the characterization of an intergenic lncRNA expressed in epithelial tissues which we termed EPR (Epithelial cell Program Regulator). EPR is rapidly downregulated by TGF-ß and its sustained expression largely reshapes the transcriptome, favors the acquisition of epithelial traits, and reduces cell proliferation in cultured mammary gland cells as well as in an animal model of orthotopic transplantation. EPR generates a small peptide that localizes at epithelial cell junctions but the RNA molecule per se accounts for the vast majority of EPR-induced gene expression changes. Mechanistically, EPR interacts with chromatin and regulates Cdkn1a gene expression by affecting both its transcription and mRNA decay through its association with SMAD3 and the mRNA decay-promoting factor KHSRP, respectively. We propose that EPR enables epithelial cells to control proliferation by modulating waves of gene expression in response to TGF-ß.


Assuntos
Estabilidade de RNA/genética , RNA Longo não Codificante/genética , Proteína Smad3/metabolismo , Transcriptoma/genética , Fator de Crescimento Transformador beta/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , RNA Longo não Codificante/efeitos dos fármacos
6.
Nat Commun ; 10(1): 2016, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043605

RESUMO

Appropriate therapeutic modulation of endothelial proliferation and sprouting is essential for the effective inhibition of angiogenesis in cancer or its induction in cardiovascular disease. The current view is that an increase in growth factor concentration, and the resulting mitogenic activity, increases both endothelial proliferation and sprouting. Here, we modulate mitogenic stimuli in different vascular contexts by interfering with the function of the VEGF and Notch signalling pathways at high spatiotemporal resolution in vivo. Contrary to the prevailing view, our results indicate that high mitogenic stimulation induced by VEGF, or Notch inhibition, arrests the proliferation of angiogenic vessels. This is due to the existence of a bell-shaped dose-response to VEGF and MAPK activity that is counteracted by Notch and p21, determining whether endothelial cells sprout, proliferate, or become quiescent. The identified mechanism should be considered to achieve optimal therapeutic modulation of angiogenesis.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Mitógenos/farmacologia , Neovascularização Patológica/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Knockout , Neovascularização Patológica/patologia , Receptores Notch/antagonistas & inibidores , Receptores Notch/metabolismo , Retina , Vasos Retinianos , Transdução de Sinais/genética , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Nat Commun ; 10(1): 2147, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089132

RESUMO

Cancer-relevant signalling pathways rely on bidirectional nucleocytoplasmic transport events through the nuclear pore complex (NPC). However, mechanisms by which individual NPC components (Nups) participate in the regulation of these pathways remain poorly understood. We discover by integrating large scale proteomics, polysome fractionation and a focused RNAi approach that Nup155 controls mRNA translation of p21 (CDKN1A), a key mediator of the p53 response. The underlying mechanism involves transcriptional regulation of the putative tRNA and rRNA methyltransferase FTSJ1 by Nup155. Furthermore, we observe that Nup155 and FTSJ1 are p53 repression targets and accordingly find a correlation between the p53 status, Nup155 and FTSJ1 expression in murine and human hepatocellular carcinoma. Our data suggest an unanticipated regulatory network linking translational control by and repression of a structural NPC component modulating the p53 pathway through its effectors.


Assuntos
Carcinoma Hepatocelular/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Neoplasias Hepáticas/patologia , Metiltransferases/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas Nucleares/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Metiltransferases/metabolismo , Camundongos , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Interferente Pequeno/metabolismo
8.
Nutrients ; 11(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987009

RESUMO

Certain antioxidative flavonoids are known to activate nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates cellular antioxidants and detoxifying response and is reportedly highly activated in many types of cancers. Few studies on the potential undesired effects of flavonoid intake during chemotherapy have been conducted, yet Nrf2 activators could favor cancer cell survival by attenuating chemotherapeutic efficiency. This study aimed to examine if luteolin, an Nrf2 activator, hinders chemotherapeutic activity of oxaliplatin, a potent anticancer agent for colorectal cancer, in HCT116 cells. Luteolin treatment strongly increased the transcriptional activity of the antioxidant response element in HCT116 cells and induced the protein expression of heme oxygenase-1, which were indicative of its Nrf2-inducing potential. Intriguingly, 25 µM luteolin reduced cell viability through apoptotic induction, which was intensified in p53-expressing cells while 1 µM oxaliplatin caused cell cycle arrest at G0/G1-phase via the p53/p21-dependent mechanism. Moreover, luteolin treatment was found to reduce oxaliplatin-treated p53-null cell viability and colony counts further, thereby demonstrating an additional effect of luteolin in the killing of human colorectal tumor HCT116 cells not expressing functional p53 protein. The findings suggest that luteolin can induce p53-mediated apoptosis regardless of oxaliplatin treatment and may eliminate oxaliplatin-resistant p53-null colorectal cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Luteolina/farmacologia , Oxaliplatina/farmacologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Elementos de Resposta Antioxidante/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células HCT116 , Heme Oxigenase-1/metabolismo , Humanos , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
9.
Phytother Res ; 33(6): 1689-1696, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30932278

RESUMO

The tumor suppressor p53 plays essential roles in cellular protection mechanisms against a variety of stress stimuli and its activation induces apoptosis or autophagy in certain cancer cells. Here, we identified protopine, an isoquinoline alkaloid isolated from Nandina domestica, as an activator of the p53 pathway from cell-based natural compound screening based on p53-responsive transcription. Protopine increased the p53-mediated transcriptional activity and promoted p53 phosphorylation at the Ser15 residue, resulting in stabilization of p53 protein. Moreover, protopine up-regulated the expression of p21WAF1/CIP1 and BAX, downstream genes of p53, and inhibited the proliferation of HCT116 colon cancer cells. Apoptosis was elicited by protopine as indicated by caspase-3/7 activation, poly ADP ribose polymerase cleavage, and increased population of Annexin V-FITC-positive cells. Furthermore, protopine induced the formation of microtubule-associated protein 1 light chain 3 (LC3) puncta and LC3-II turnover, typical biochemical markers of autophagy, in HCT116 cells. Our findings suggest that protopine exerts its antiproliferative activity by stimulating the p53 pathway and may have potential as a chemopreventive agent for human colon cancer.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Benzofenantridinas/isolamento & purificação , Benzofenantridinas/uso terapêutico , Alcaloides de Berberina/isolamento & purificação , Alcaloides de Berberina/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Ranunculales/química , Apoptose/fisiologia , Autofagia/fisiologia , Benzofenantridinas/farmacologia , Berberidaceae/química , Berberidaceae/classificação , Alcaloides de Berberina/farmacologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta a Droga , Células HCT116 , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Ranunculales/classificação , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
PLoS Genet ; 15(4): e1008058, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933982

RESUMO

In the skin and gill epidermis of fish, ionocytes develop alongside keratinocytes and maintain body fluid ionic homeostasis that is essential for adaptation to environmental fluctuations. It is known that ionocyte progenitors in zebrafish embryos are specified from p63+ epidermal stem cells through a patterning process involving DeltaC (Dlc)-Notch-mediated lateral inhibition, which selects scattered dlc+ cells into the ionocyte progenitor fate. However, mechanisms by which the ionocyte progenitor population is modulated remain unclear. Krüppel-like factor 4 (Klf4) transcription factor was previously implicated in the terminal differentiation of mammalian skin epidermis and is known for its bifunctional regulation of cell proliferation in a tissue context-dependent manner. Here, we report novel roles for zebrafish Klf4 in the ventral ectoderm during embryonic skin development. We found that Klf4 was expressed in p63+ epidermal stem cells of the ventral ectoderm from 90% epiboly onward. Knockdown or knockout of klf4 expression reduced the proliferation rate of p63+ stem cells, resulting in decreased numbers of p63+ stem cells, dlc-p63+ keratinocyte progenitors and dlc+ p63+ ionocyte progenitor cells. These reductions subsequently led to diminished keratinocyte and ionocyte densities and resulted from upregulation of the well-known cell cycle regulators, p53 and cdkn1a/p21. Moreover, mutation analyses of the KLF motif in the dlc promoter, combined with VP16-klf4 or engrailed-klf4 mRNA overexpression analyses, showed that Klf4 can bind the dlc promoter and modulate lateral inhibition by directly repressing dlc expression. This idea was further supported by observing the lateral inhibition outcomes in klf4-overexpressing or knockdown embryos. Overall, our experiments delineate novel roles for zebrafish Klf4 in regulating the ionocyte progenitor population throughout early stem cell stage to initiation of terminal differentiation, which is dependent on Dlc-Notch-mediated lateral inhibition.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Padronização Corporal , Diferenciação Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ectoderma/citologia , Ectoderma/embriologia , Ectoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Brânquias/citologia , Brânquias/embriologia , Brânquias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transporte de Íons , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Receptores Notch/genética , Receptores Notch/metabolismo , Transativadores/genética , Transativadores/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
11.
Anticancer Res ; 39(4): 1849-1857, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952725

RESUMO

BACKGROUND/AIM: Melanoma-associated antigen A12 (MAGEA12) has recently been reported as a repressor of tumor-suppressor genes. This study aimed to investigate the implications of MAGEA12 expression in the pathogenesis of cutaneous squamous cell carcinoma (cSCC). MATERIALS AND METHODS: MAGEA12 and p21 expression were investigated in 15 samples of normal skin and 111 of cSCC tissues by immunohistochemistry. The biological functions of MAGEA12 in cSCC were also investigated both in vitro and in vivo. RESULTS: Expression of both MAGEA12 and p21 was significantly increased in cSCC. MAGEA12 expression showed a positive correlation, while p21 expression showed negative correlation with the recurrence-free survival of patients with cSCC. In addition, MAGEA12 knockdown significantly attenuated proliferative, migratory, invasive, and tumorigenic activities of cSCC cells and was negatively correlated with p21 expression both in vitro and in vivo. CONCLUSION: MAGEA12-mediated down-regulation of p21 may be involved in cSCC pathogenesis and MAGEA12 may serve as a molecular biomarker in cSCC.


Assuntos
Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Intervalo Livre de Progressão , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Adulto Jovem
12.
Mol Cell Biochem ; 458(1-2): 49-59, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30911957

RESUMO

Berberine has shown anticancer properties and has potential for a chemopreventive and/or chemotherapeutic agent for breast cancer. Berberine showed cytotoxicity to breast cancer cells, with an increase in the levels of p21/cip1 and p27/kip1, cyclin-dependent kinase inhibitors (CDKI), but mechanisms involved in up-regulating these molecules are largely unknown. Herein, we studied the key regulatory mechanisms involved in berberine-mediated up-regulation of p21/cip1 and p27/kip1. Berberine treatment for 24 and 48 h decreased the number of cells by 44-84% (P < 0.0001) and 38-78% (P < 0.0001), and increased cell death by 12-17% (P < 0.005) and 38-78% (P < 0.0001) in MCF-7 and MDA-MB-231 cells, respectively. Cells were arrested in G1 phase by berberine which was accompanied with up-regulation of mRNA and protein level of both p21/cip1 and p27/kip1. Berberine decreased the expression of protein levels of cyclin D1, cyclin E, CDK2, CDK4, and CDK6 to cause G1 phase arrest. Berberine caused nuclear localization of p21/cip1 in both the cell lines. Our data for the first time showed that the post-translational stability of both the proteins was strongly increased by berberine as examined by cycloheximide chase assay. Inhibition of Akt was associated with berberine-mediated up-regulation of p21/cip1 and also led to a decrease in cell viability accompanied with significant G1 phase cell cycle arrest. Our study revealed that berberine not only up-regulates mRNA and protein levels of p21/cip1 and p27/kip1 but also increases their nuclear localization and post-translational protein stability. Further, Akt inhibition was found to mediate berberine-mediated up-regulation of p21/cip1 but not the p27/kip1.


Assuntos
Berberina/farmacologia , Neoplasias da Mama/tratamento farmacológico , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/biossíntese , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Humanos , Células MCF-7 , Estabilidade Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética
13.
Fish Shellfish Immunol ; 88: 198-206, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30826413

RESUMO

Viral capsid proteins play an important role in the viral infection process. To identify the cellular proteins in shrimp that interact with the Penaeus stylirostris densovirus capsid protein (PstDNV-CP), we constructed a yeast two-hybrid (Y2H) cDNA library of the muscle tissue of Litopenaeus vannamei, and hybridized the bait vector pGBKT7-CP with this library. Cloning and sequencing showed that the shrimp protein interacting with PstDNV-CP was a homolog of BRCA2 and CDKN1A(p21)-interacting protein (BCCIP). We named this protein L. vannamei BCCIP (LvBCCIP). Further analysis showed that LvBCCIP interacted with L. vannamei calmodulin (LvCaM). We validated the interactions between PstDNV-CP and LvBCCIP, and between LvBCCIP and LvCaM, with GST pulldown assays. The gene expression of LvBCCIP increased significantly after PstDNV challenge. In addition, the PstDNV titer of PstDNV-challenged shrimp was significantly reduced after LvBCCIP expression was inhibited using double-stranded RNA (dsRNA) interference. These results indicated that LvBCCIP is critical to PstDNV pathogenesis in L. vannamei. Interestingly, the growth rate of L. vannamei was significantly reduced when LvBCCIP gene expression was silenced, indicating that LvBCCIP may also be associated with growth regulation in L. vannamei. Thus, the interaction between PstDNV-CP and LvBCCIP might explain why PstDNV infection leads to runt-deformity syndrome in shrimp.


Assuntos
Proteínas do Capsídeo/metabolismo , Densovirus/fisiologia , Penaeidae/virologia , Animais , Proteína BRCA2/metabolismo , Calmodulina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Expressão Gênica , Penaeidae/crescimento & desenvolvimento , Interferência de RNA
14.
J Agric Food Chem ; 67(17): 4808-4816, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30888162

RESUMO

Cellular senescence is the state of irreversible cell cycle arrest that provides a blockade during oncogenic transformation and tumor development. Avenanthramide A (AVN A) is an active ingredient exclusively extracted from oats, which possesses antioxidant, anti-inflammatory, and anticancer activities. However, the underlying mechanism(s) of AVN A in the prevention of cancer progression remains unclear. In the current study, we revealed that AVN A notably attenuated tumor formation in an azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model. AVN A treatment triggered cellular senescence in human colon cancer cells, evidenced by enlarging cellular size, upregulating ß-galactosidase activity, γ-H2AX positive staining, and G1 phase arrest. Moreover, AVN A treatment significantly increased the expression of miR-129-3p, which markedly repressed the E3 ubiquitin ligase Pirh2 and two other targets, IGF2BP3 and CDK6. The Pirh2 silencing by miR-129-3p led to a significant increase in protein levels of p53 and its downstream target p21, which subsequently induced cell senescence. Taken together, our data indicate that miR-129-3p/Pirh2/p53 is a critical signaling pathway in AVN A induced cellular senescence and AVN A could be a potential chemopreventive strategy for cancer treatment.


Assuntos
Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , ortoaminobenzoatos/administração & dosagem , Animais , Ciclo Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/fisiopatologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética
15.
Mater Sci Eng C Mater Biol Appl ; 99: 322-332, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889706

RESUMO

Vascular disease is a major complication of aging, but the molecular mechanisms underlying the aging-induced vascular dysfunction remain unclear, and there is no effective treatment to prevent aging induced diseases. The objectives of the present study are to identify the signaling pathway mediating aging-induced vascular dysfunction and to develop an exosome based therapy to inhibit aging process. We used 11-month-old C57BL6 mice as pre-aging animal model and H2O2 treated H9C2 cells as an in vitro aging model to examine the therapeutic effect of miR-675. We found decreased expression of the potential aging modulator miR-675 in aging muscle, and H2O2 treatment decreased the expression of miR-675 and upregulated the expression of the aging marker ß-gal and TGF-ß1. We also found that miR-675 mimic decreased ß-gal staining in H2O2 treated H9C2 cells. Dual-luciferase reporter assays verified TGF-ß1 as the target gene of miR-675. Moreover, senescent H9C2 cells incubated with exosomes isolated from UMSCs transfected with the miR-675 mimic showed increased expression of miR-675, reduced activity of the aging marker ß-gal and reduced protein levels of TGF-ß1. We employed silk fibroin hydrogel to encapsulate exosomes in order to prolong the half-life of exosome in vivo. Fourier transform infrared spectroscopy (FTIR) revealed that exosomes were successfully encapsulated by the hydrogel. Laser Doppler perfusion imaging showed that the miR-675 exosomes encapsulated in silk fibroin hydrogel promote blood perfusion in ischemic hindlimbs. We demonstrated that miR-675 exosomes encapsulated in silk fibroin hydrogel provided sustained release of exosomes in vitro, and increased the retention time of red fluorescent PKH26-exosome in the tissue. Taken together, this study identified miR-675 as an important regulator of cell senescence and provided a novel strategy to deliver powerful exosomes by silk fibroin hydrogel to treat aging-induced vascular dysfunction.


Assuntos
Envelhecimento/patologia , Exossomos/metabolismo , Fibroínas/química , Técnicas de Transferência de Genes , Membro Posterior/fisiopatologia , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Animais , Sequência de Bases , Bombyx , Forma Celular , Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Membro Posterior/irrigação sanguínea , Humanos , Camundongos , MicroRNAs/genética , Perfusão , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Cordão Umbilical/citologia
16.
Chem Biol Interact ; 304: 106-123, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30840857

RESUMO

Naphthalene diimide (NDI) derivatives have been shown to exhibit promising antineoplastic properties. In the current study, we assessed the anticancer and anti-bacterial properties of di-substituted NDI derivative. The naphthalene-bis-hydrazimide, 1, negatively affected the cell viability of three cancer cell lines (AGS, HeLa and PC3) and induced S phase cell cycle arrest along with SubG0/G1 accumulation. Amongst three cell lines, gastric cancer cell line, AGS, showed the highest sensitivity towards the NDI derivative 1. Compound 1 induced extensive DNA double strand breaks causing p53 activation leading to transcription of p53 target gene p21 in AGS cells. Reduction in protein levels of p21 and BRCA1 suggested that 1 treated AGS cells underwent cell death due to accumulation of DNA damage as a result of impaired DNA damage repair. ß-catenin downregulation and consequently decrease in levels of c-Myc may have led to 1 induced AGS cell proliferation inhibition.1 induced AGS cell S phase arrest was mediated through CylinA/CDK2 downregulation. The possible mechanisms involved in anticancer activity of 1 includes ROS upregulation, induction of DNA damage, disruption of mitochondrial membrane potential causing ATP depletion, inhibition of cell proliferation and downregulation of antiapoptotic factors ultimately leading to mitochondria mediated apoptosis. Further compound 1 also inhibited H. pylori proliferation as well as H. pylori induced morphological changes in AGS cells. These findings suggest that NDI derivative 1 exhibits two-pronged anticancer activity, one by directly inhibiting cancer cell growth and inducing apoptosis and the other by inhibiting H. pylori.


Assuntos
Adenocarcinoma/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Regulação para Baixo/efeitos dos fármacos , Imidas/farmacologia , Naftalenos/farmacologia , Proteínas Proto-Oncogênicas c-myc/biossíntese , Fase S/efeitos dos fármacos , Neoplasias Gástricas/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Proteínas Proto-Oncogênicas c-myc/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
PLoS One ; 14(1): e0203577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30703085

RESUMO

RB-E2F transcriptional control plays a key role in regulating the timing of cell cycle progression from G1 to S-phase in response to growth factor stimulation. Despite this role, it is genetically dispensable for cell cycle exit in primary fibroblasts in response to growth arrest signals. Mice engineered to be defective for RB-E2F transcriptional control at cell cycle genes were also found to live a full lifespan with no susceptibility to cancer. Based on this background we sought to probe the vulnerabilities of RB-E2F transcriptional control defects found in Rb1R461E,K542E mutant mice (Rb1G) through genetic crosses with other mouse strains. We generated Rb1G/G mice in combination with Trp53 and Cdkn1a deficiencies, as well as in combination with KrasG12D. The Rb1G mutation enhanced Trp53 cancer susceptibility, but had no effect in combination with Cdkn1a deficiency or KrasG12D. Collectively, this study indicates that compromised RB-E2F transcriptional control is not uniformly cancer enabling, but rather has potent oncogenic effects when combined with specific vulnerabilities.


Assuntos
Fatores de Transcrição E2F/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Proteína do Retinoblastoma/genética , Animais , Carcinogênese/genética , Ciclo Celular/genética , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Fibroblastos , Predisposição Genética para Doença , Humanos , Antígeno Ki-67/análise , Camundongos , Camundongos Transgênicos , Mutação , Neoplasias/patologia , Cultura Primária de Células , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Medicina (Kaunas) ; 55(2)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30700046

RESUMO

BACKGROUND AND OBJECTIVE: Alterations in gene expressions are often due to epigenetic modifications that can have a significant influence on cancer development, growth, and progression. Lately, histone deacetylase inhibitors (HDACi) such as suberoylanilide hydroxamic acid (SAHA, or vorinostat, MK0683) have been emerging as a new class of drugs with promising therapeutic benefits in controlling cancer growth and metastasis. The small molecule RG7388 (idasanutlin, R05503781) is a newly developed inhibitor that is specific for an oncogene-derived protein called MDM2, which is also in clinical trials for the treatment of various types of cancers. These two drugs have shown the ability to induce p21 expression through distinct mechanisms in MCF-7 and LNCaP cells, which are reported to have wild-type TP53. Our understanding of the molecular mechanism whereby SAHA and RG7388 can induce cell cycle arrest and trigger cell death is still evolving. In this study, we performed experiments to measure the cell cycle arrest effects of SAHA and RG7388 using MCF-7 and LNCaP cells. MATERIALS AND METHODS: The cytotoxicity, cell cycle arrest, and apoptosis/necroptosis effects of the SAHA and RG7388 treatments were assessed using the Trypan Blue dye exclusion (TBDE) method, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, fluorescence assay with DEVD-amc substrate, and immunoblotting methods. RESULTS: The RG7388 treatment was able to induce cell death by elevating p21WAF1/CIP1 through inhibition of MDM2 in LNCaP, but not in MCF-7 cells, even though there was evidence of p53 elevation. Hence, we suspect that there is some level of uncoupling of p53-mediated transcriptional induction of p21WAF1/CIP1 in MCF-7 cells. CONCLUSION: Our results from MCF-7 and LNCaP cells confirmed that SAHA and RG7388 treatments were able to induce cell death via a combination of cell cycle arrest and cytotoxic mechanisms. We speculate that our findings could lead to the development of newer treatments for breast and prostate cancers with drug combinations including HDACi.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Pirrolidinas/farmacologia , Vorinostat/farmacologia , para-Aminobenzoatos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Feminino , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Células MCF-7 , Masculino , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Pirrolidinas/uso terapêutico , Proteína Supressora de Tumor p53/biossíntese , Vorinostat/uso terapêutico , para-Aminobenzoatos/uso terapêutico
19.
Andrologia ; 51(5): e13243, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30746737

RESUMO

This study is aimed to analyse the cross-link between cyclin D1, cdk-4, p21, PCNA and DNA damage during different periods of reperfusion following experimental torsion in rats. Thirty mature male Wistar rats (N = 6) were used. Following 4 hr from torsion induction, the reperfusion was induced. Animals were subdivided into groups, including 4 hr torsion-induced (T1), 1 hr post-reperfusion (T2), 2 hr post-reperfusion (T3), 4 hr post-reperfusion (T4) and 8 hr post-reperfusion (T5) groups. The seminiferous tubules differentiation (TDI) and spermatogenesis indices were evaluated. The expressions of cyclin D1, cdk-4, p21and PCNA were analysed using Reverse Transcriptase-PCR (RT-PCR). Moreover, the cyclin D1+ , cdk-4+ , p21+ and PCNA+ cell numbers/mm2 of tissue were assessed through immunohistochemical staining. The testicular DNA fragmentation was analysed using TUNEL assay and DNA ladder test. Observations demonstrated that reperfusion significantly increased (p < 0.05) up-regulated the expressions of cyclin D1, cdk-4 and PCNA. The animals in T5 group showed diminished expression of p21 and represented diminished DNA fragmentation versus T1 group. In conclusion, minimum 8 hr post-reperfusion is needed to re-initiate necessary expressions of cyclin D1, cdk-4 and PCNA to restore cell cycling machinery and ameliorate torsion-induced DNA damage.


Assuntos
Fragmentação do DNA , Traumatismo por Reperfusão/patologia , Torção do Cordão Espermático/patologia , Espermatozoides/patologia , Animais , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Humanos , Masculino , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Túbulos Seminíferos/crescimento & desenvolvimento , Túbulos Seminíferos/metabolismo , Torção do Cordão Espermático/complicações , Espermatogênese/fisiologia , Espermatozoides/metabolismo , Regulação para Cima
20.
Molecules ; 24(3)2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754632

RESUMO

Pyrano[2,3-c]pyrazole derivatives have been reported as exerting various biological activities. One compound with potential anti-tumor activity was screened out by MTT assay from series of dihydropyrazopyrazole derivatives we had synthesized before using a one-pot, four-component reaction, and was named as 6-amino-4-(2-hydroxyphenyl)-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (hereinafter abbreviated as AMDPC). The IC50 of AMDPC against Bcap-37 breast cancer cells was 46.52 µg/mL. Then the hydrophobic AMDPC was encapsulated in PEG-PLGA block copolymers, and then self-assembled as polymeric micelle (mPEG-PLGA/AMDPC) to improve both physiochemical and release profiles. The effect of mPEG-PLGA/AMDPC on BCAP-37 cancer cells showed similar anti-tumor effects as AMDPC. Furthermore, the anti-tumor mechanism of mPEG-PLGA/AMDPC was investigated, which can probably be attributed to stimulating the expression of P21 gene and therefore protein production on BCAP-37 cells, and then blocked the cell cycle through the P53-independent pathway both in S phase and G2 phase. Thus, mPEG-PLGA/AMDPC is a promising therapeutic agent for cancer treatment, and further in vivo studies will be developed.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pirazolonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Células MCF-7 , Micelas , Nanotecnologia , Poliésteres/química , Polietilenoglicóis/química , Pirazolonas/síntese química , Pirazolonas/química , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA