Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29.247
Filtrar
1.
Nat Commun ; 11(1): 4467, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948751

RESUMO

Recent studies have reported that upregulation of disulfide-bond A oxidoreductase-like protein (DsbA-L) prevented lipid-induced renal injury in diabetic nephropathy (DN). However, the role and regulation of proximal tubular DsbA-L for renal tubulointerstitial fibrosis (TIF) remains unclear. In current study, we found that a proximal tubules-specific DsbA-L knockout mouse (PT-DsbA-L-KO) attenuated UUO-induced TIF, renal cell apoptosis and inflammation. Mechanistically, the DsbA-L interacted with Hsp90 in mitochondria of BUMPT cells which activated the signaling of Smad3 and p53 to produce connective tissue growth factor (CTGF) and then resulted in accumulation of ECM of BUMPT cells and mouse kidney fibroblasts. In addition, the progression of TIF caused by UUO, ischemic/reperfusion (I/R), aristolochic acid, and repeated acute low-dose cisplatin was also alleviated in PT-DsbA-L-KO mice via the activation of Hsp90 /Smad3 and p53/CTGF axis. Finally, the above molecular changes were verified in the kidney biopsies from patients with obstructive nephropathy (Ob). Together, these results suggest that DsbA-L in proximal tubular cells promotes TIF via activation of the Hsp90 /Smad3 and p53/CTGF axis.


Assuntos
Fibrose/genética , Predisposição Genética para Doença/genética , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Nefropatias/genética , Idoso , Animais , Apoptose , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Nefropatias Diabéticas , Modelos Animais de Doenças , Feminino , Fibrose/patologia , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Inflamação , Rim/lesões , Nefropatias/patologia , Túbulos Renais Proximais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Proteína Supressora de Tumor p53/metabolismo
2.
Adv Exp Med Biol ; 1268: 307-318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32918225

RESUMO

It has now been convincingly shown that vitamin D and p53 signaling protect against spontaneous or carcinogen-induced malignant transformation of cells. The vitamin D receptor (VDR) and the p53/p63/p73 proteins (the p53 family hereafter) exert their effects as receptors/sensors that turn into transcriptional regulators upon stimulus. While the p53 clan, mostly in the nucleoplasm, responds to a large and still growing number of alterations in cellular homeostasis commonly referred to as stress, the nuclear VDR is transcriptionally activated after binding its naturally occurring biologically active ligand 1,25-dihydroxyvitamin D with high affinity. Interestingly, a crosstalk between vitamin D and p53 signaling has been demonstrated that occurs at different levels, has genome-wide implications, and is of high importance for many malignancies, including non-melanoma skin cancer. These interactions include the ability of p53 to upregulate skin pigmentation via POMC derivatives including alpha-MSH and ACTH. Increased pigmentation protects the skin against UV-induced DNA damage and skin photocarcinogenesis, but also inhibits cutaneous synthesis of vitamin D. A second level of interaction is characterized by binding of VDR and p53 protein, an observation that may be of relevance for the ability of 1,25-dihydroxyvitamin D to increase the survival of skin cells after UV irradiation. UV irradiation-surviving cells show significant reductions in thymine dimers in the presence of 1,25-dihydroxyvitamin D that are associated with increased nuclear p53 protein expression and significantly reduced NO products. A third level of interaction is documented by the ability of vitamin D compounds to regulate the expression of the murine double minute (MDM2) gene in dependence of the presence of wild-type p53. MDM2 has a well-established role as a key negative regulator of p53 activity. Finally, p53 and its family members have been implicated in the direct regulation of the VDR. This review gives an update on some of the implications of the crosstalk between vitamin D and p53 signaling for carcinogenesis in the skin and other tissues, focusing on a genome-wide perspective.


Assuntos
Neoplasias/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Vitamina D/metabolismo , Animais , Humanos , Raios Ultravioleta/efeitos adversos , Vitaminas/metabolismo
3.
Anticancer Res ; 40(9): 4857-4867, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878773

RESUMO

BACKGROUND/AIM: Anticancer peptide PNC-27 binds to HDM-2 protein on cancer cell membranes inducing the formation of cytotoxic transmembrane pores. Herein, we investigated HDM-2 membrane expression and the effect of PNC-27 treatment on human non-stem cell acute myelogenous leukemia cell lines: U937, acute monocytic leukemia; OCI-AML3, acute myelomonocytic leukemia and HL60, acute promyelocytic leukemia. MATERIALS AND METHODS: We measured cell surface membrane expression of HDM-2 using flow cytometry. Cell viability was assessed using MTT assay while direct cytotoxicity was measured by lactate dehydrogenase (LDH) release and induction of apoptotic markers annexin V and caspase-3. RESULTS: HDM-2 is expressed at high levels in membranes of U937, OCI-AML3 and HL-60 cells. PNC-27 can bind to membrane HDM-2 to induce cell necrosis and LDH release within 4 h. CONCLUSION: Targeting membrane HDM-2 can be a potential strategy to treat leukemia. PNC-27 targeting membrane HDM-2 demonstrated significant anti-leukemia activity in a variety of leukemic cell lines.


Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide/patologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/farmacologia , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , L-Lactato Desidrogenase/metabolismo , Leucemia Mieloide/metabolismo , Necrose , Proteína Supressora de Tumor p53/metabolismo
4.
Anticancer Res ; 40(9): 4961-4968, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878784

RESUMO

BACKGROUND/AIM: Despite advances in treatment modalities, the visual prognosis of retinoblastoma still remains unsatisfactory, underscoring the need to develop novel therapeutic approaches. MATERIALS AND METHODS: The effect on the growth of six human retinoblastoma cell lines and a normal human fibroblast cell line of CEP1347, a small-molecule kinase inhibitor originally developed for the treatment of Parkinson's disease and therefore with a known safety profile in humans, was examined. The role of the P53 pathway in CEP1347-induced growth inhibition was also investigated. RESULTS: CEP1347 selectively inhibited the growth of retinoblastoma cell lines expressing murine double minute 4 (MDM4), a P53 inhibitor. Furthermore, CEP1347 reduced the expression of MDM4 and activated the P53 pathway in MDM4-expressing retinoblastoma cells, which was required for the inhibition of their growth by CEP1347. CONCLUSION: We propose CEP1347 as a promising candidate for the treatment of retinoblastomas, where functional inactivation of P53 as a result of MDM4 activation is reportedly common.


Assuntos
Antineoplásicos/farmacologia , Carbazóis/farmacologia , Retinoblastoma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reposicionamento de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Retinoblastoma/metabolismo , Retinoblastoma/patologia
5.
Anticancer Res ; 40(9): 4979-4987, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878786

RESUMO

BACKGROUND/AIM: Multiple myeloma is a highly heterogeneous disease of clonal plasma cells. Histone deacetylase (HDAC) inhibitors are promising anticancer drugs but their precise mechanisms of actions are not well understood. MATERIALS AND METHODS: Cell-cycle regulation and pro-apoptotic effects of two histone deacetylase inhibitors, suberohydroxamic acid (SAHA) and suberoylanilide hydroxamic acid (SBHA), were analyzed in multiple myeloma cell lines RPMI8226 and U266 with differing TP53 status using gene-expression analysis. RESULTS: Enhanced expression of cyclin-dependent kinase inhibitor 1A (CDKN1A/p21WAF/CIP1) detected in the TP53-deleted U266 cell line after SAHA treatment indicates the P53-independent mode of transcriptional activation of CDKN1A gene. In contrast, CDKN1A gene expression was significantly increased by both SBHA and SAHA treatment of TP53-mutated RPMI8226 cells. CONCLUSION: SAHA appears to be a potentially effective pro-apoptotic and anticancer drug with universal application in the treatment of heterogeneous populations of multiple myeloma cells.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/genética , Mieloma Múltiplo/patologia , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Proteína Supressora de Tumor p53/genética
6.
Nat Commun ; 11(1): 4586, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934222

RESUMO

Frequent mutation of the tumour suppressor RNF43 is observed in many cancers, particularly colon malignancies. RNF43, an E3 ubiquitin ligase, negatively regulates Wnt signalling by inducing degradation of the Wnt receptor Frizzled. In this study, we discover that RNF43 activity requires phosphorylation at a triplet of conserved serines. This phospho-regulation of RNF43 is required for zebrafish development and growth of mouse intestinal organoids. Cancer-associated mutations that abrogate RNF43 phosphorylation cooperate with active Ras to promote tumorigenesis by abolishing the inhibitory function of RNF43 in Wnt signalling while maintaining its inhibitory function in p53 signalling. Our data suggest that RNF43 mutations cooperate with KRAS mutations to promote multi-step tumorigenesis via the Wnt-Ras-p53 axis in human colon cancers. Lastly, phosphomimetic substitutions of the serine trio restored the tumour suppressive activity of extracellular oncogenic mutants. Therefore, harnessing phospho-regulation of RNF43 might be a potential therapeutic strategy for tumours with RNF43 mutations.


Assuntos
Carcinogênese/metabolismo , Receptores Wnt/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Carcinogênese/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Proteína Oncogênica p21(ras)/genética , Proteína Oncogênica p21(ras)/metabolismo , Fosforilação , Proteólise , Receptores Wnt/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Via de Sinalização Wnt
7.
J Environ Pathol Toxicol Oncol ; 39(2): 179-189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32749126

RESUMO

Ginkgo biloba extract EGb761 conveys an anticancer effect, but little is known regarding its role in hepatocellular carcinoma (HCC). Our study aims to determine the anticancer effect of EGb761 on HCC cell lines and clarify the underlying molecular mechanism. We explore biological functions of EGb761 in HCC using morphological observation, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cytotoxic analysis. We investigate the effects of EGb761 on proliferation and apoptosis of HCC cells using plate clone formation, proliferating cell nuclear antigen, and terminal deoxynucleotidyl transferase d-untranslated protein nick end labeling assays. Protein expressions of the NF-κB/p53 signal pathway were detected and identified using immunohistochemistry. The effect of EGb761 on the p53 signaling pathway was further confirmed by adding pifithrin (PFT)-α, an inhibitor of p53. We determine that EGb761 inhibits cell growth, reduces cell viability, and promotes apoptosis of HCC cells. In addition, EGb761 reduces proliferation and increases apoptosis of human hepatocellular carcinomas (HepG2) cells in a dose-dependent manner. We also find that EGb761 exerts an anticancer effect on HepG2 cells by activating p53 and inhibiting nuclear factor (NF)-κB signaling pathways. This study confirms that EGb761 inhibits proliferation and triggers apoptosis of HCC cells through the NF-κB/p53 signaling pathway.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
8.
Nat Commun ; 11(1): 4287, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855419

RESUMO

Warsaw Breakage Syndrome (WABS) is a rare disorder related to cohesinopathies and Fanconi anemia, caused by bi-allelic mutations in DDX11. Here, we report multiple compound heterozygous WABS cases, each displaying destabilized DDX11 protein and residual DDX11 function at the cellular level. Patient-derived cell lines exhibit sensitivity to topoisomerase and PARP inhibitors, defective sister chromatid cohesion and reduced DNA replication fork speed. Deleting DDX11 in RPE1-TERT cells inhibits proliferation and survival in a TP53-dependent manner and causes chromosome breaks and cohesion defects, independent of the expressed pseudogene DDX12p. Importantly, G-quadruplex (G4) stabilizing compounds induce chromosome breaks and cohesion defects which are strongly aggravated by inactivation of DDX11 but not FANCJ. The DNA helicase domain of DDX11 is essential for sister chromatid cohesion and resistance to G4 stabilizers. We propose that DDX11 is a DNA helicase protecting against G4 induced double-stranded breaks and concomitant loss of cohesion, possibly at DNA replication forks.


Assuntos
Anormalidades Múltiplas/etiologia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Quadruplex G , Troca de Cromátide Irmã , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Proliferação de Células , RNA Helicases DEAD-box/química , DNA Helicases/química , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Estabilidade Proteica , Pseudogenes , RNA Helicases/genética , RNA Helicases/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Síndrome , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
9.
PLoS Pathog ; 16(8): e1008792, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32813746

RESUMO

Tumor suppressors can exert pro-proliferation functions in specific contexts. In the beta human papillomavirus type 38 (HPV38) experimental model, the viral proteins E6 and E7 promote accumulation of a wild-type (WT) p53 form in human keratinocytes (HKs), promoting cellular proliferation. Inactivation of p53 by different means strongly decreases the proliferation of HPV38 E6/E7 HKs. This p53 form is phosphorylated at S392 by the double-stranded RNA-dependent protein kinase PKR, which is highly activated by HPV38. PKR-mediated S392 p53 phosphorylation promotes the formation of a p53/DNMT1 complex, which inhibits expression of integrin alpha 1 (ITGA1), a repressor of epidermal growth factor receptor (EGFR) signaling. Ectopic expression of ITGA1 in HPV38 E6/E7 HKs promotes EGFR degradation, inhibition of cellular proliferation, and cellular death. Itga1 expression was also inhibited in the skin of HPV38 transgenic mice that have an elevated susceptibility to UV-induced skin carcinogenesis. In summary, these findings reveal the existence of a specific WT p53 form that displays pro-proliferation properties.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Proliferação de Células , Queratinócitos/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/complicações , Proteínas Repressoras/metabolismo , Neoplasias Cutâneas/etiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Células Cultivadas , Regulação para Baixo , Humanos , Queratinócitos/imunologia , Queratinócitos/virologia , Camundongos , Camundongos Transgênicos , Proteínas Oncogênicas Virais/genética , Papillomaviridae/isolamento & purificação , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/virologia , Proteínas Repressoras/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/genética
10.
Yakugaku Zasshi ; 140(8): 963-968, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741869

RESUMO

Metabolome analysis is an approach to investigate cell characteristics from the metabolites that are constantly produced and changed by those cells. We conducted a metabolome analysis of the response of 786-O renal cell carcinoma (RCC) cells to histone deacetylase (HDAC) inhibitors, which are expected to increase anticancer drug sensitivity, and compared the response with that of drug-resistant cells. Trichostatin A (TSA), an HDAC inhibitor, increased the sensitivity of 786-O cells to sunitinib. Moreover, TCA cycle and nucleotide metabolism of the cells were promoted. The findings that acetylated p53 (active form) and early apoptotic cells were increased suggests that the mechanism involved enhancement of mitochondrial metabolism and function. In addition, established sunitinib-resistant RCC cells were exposed to a combination of sunitinib and TSA, resulting in significant growth inhibition. Principal component analysis revealed that the parent and resistant cells were obviously different, but approximately half their fluctuations were illustrated by the same pathways. In summary, it was suggested that TSA reduced sunitinib resistance by triggering intracellular metabolome shifts in energy metabolism. This was the first recognized mechanism of action of TSA as an HDAC inhibitor.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Metaboloma , Metabolômica , Sunitinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Humanos , Mitocôndrias/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
11.
PLoS One ; 15(8): e0237669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810137

RESUMO

Pancreatic beta cell death is a hallmark of type 1 and 2 diabetes (T1D/T2D), but the underlying molecular mechanisms are incompletely understood. Key proteins of the DNA damage response (DDR), including tumor protein P53 (P53, also known as TP53 or TRP53 in rodents) and Ataxia Telangiectasia Mutated (ATM), a kinase known to act upstream of P53, have been associated with T2D. Here we test and compare the effect of ATM and P53 ablation on beta cell survival in the rat beta cell line Ins1E. We demonstrate that ATM and P53 differentially regulate beta cell apoptosis induced upon fundamentally different types of diabetogenic beta cell stress, including DNA damage, inflammation, lipotoxicity and endoplasmic reticulum (ER) stress. DNA damage induced apoptosis by treatment with the commonly used diabetogenic agent streptozotocin (STZ) is regulated by both ATM and P53. We show that ATM is a key STZ induced activator of P53 and that amelioration of STZ induced cell death by inhibition of ATM mainly depends on P53. While both P53 and ATM control lipotoxic beta cell apoptosis, ATM but not P53 fails to alter inflammatory beta cell death. In contrast, tunicamycin induced (ER stress associated) apoptosis is further increased by ATM knockdown or inhibition, but not by P53 knockdown. Our results reveal differential roles for P53 and ATM in beta cell survival in vitro in the context of four key pathophysiological types of diabetogenic beta cell stress, and indicate that ATM can use P53 independent signaling pathways to modify beta cell survival, dependent on the cellular insult.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sobrevivência Celular/genética , Células Secretoras de Insulina/patologia , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Diabetes Mellitus/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Técnicas de Silenciamento de Genes , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Ratos , Estreptozocina/toxicidade , Tunicamicina/toxicidade
12.
PLoS One ; 15(8): e0236881, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745107

RESUMO

PIERCE1, p53 induced expression 1 in Rb null cells, is a novel p53 target involved in the DNA damage response and cell cycle in mice. These facts prompted us to study the function of PIERCE1 with respect to p53-associated pathophysiology of cancer in humans. Unexpectedly, PIERCE1 did not respond to overexpression and activation of p53 in humans. In this study, we swapped p53 protein expression in human and mouse cells to find the clue of this difference between species. Human p53 expression in mouse cells upregulated PIERCE1 expression, suggesting that p53-responsive elements on the PIERCE1 promoter are crucial, but not the p53 protein itself. Indeed, in silico analyses of PIERCE1 promoters revealed that p53-responsive elements identified in mice are not conserved in humans. Consistently, chromatin immunoprecipitation-sequencing (ChIP-seq) analyses confirmed p53 enrichment against the PIERCE1 promoter region in mice, not in human cells. To complement the p53 study in mice, further promoter analyses suggested that the human PIERCE1 promoter is more similar to guinea pigs, lemurs, and dogs than to rodents. Taken together, our results confirm the differential responsiveness of PIERCE1 expression to p53 due to species differences in PIERCE1 promoters. The results also show partial dissimilarity after p53 induction between mice and humans.


Assuntos
Proteínas de Ciclo Celular , Elementos de Resposta/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/genética , Humanos , Camundongos , Regiões Promotoras Genéticas , Transcrição Genética/fisiologia
13.
Nat Commun ; 11(1): 3839, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737294

RESUMO

Chromatin regulates spatiotemporal gene expression during neurodevelopment, but it also mediates DNA damage repair essential to proliferating neural progenitor cells (NPCs). Here, we uncover molecularly dissociable roles for nucleosome remodeler Ino80 in chromatin-mediated transcriptional regulation and genome maintenance in corticogenesis. We find that conditional Ino80 deletion from cortical NPCs impairs DNA double-strand break (DSB) repair, triggering p53-dependent apoptosis and microcephaly. Using an in vivo DSB repair pathway assay, we find that Ino80 is selectively required for homologous recombination (HR) DNA repair, which is mechanistically distinct from Ino80 function in YY1-associated transcription. Unexpectedly, sensitivity to loss of Ino80-mediated HR is dependent on NPC division mode: Ino80 deletion leads to unrepaired DNA breaks and apoptosis in symmetric NPC-NPC divisions, but not in asymmetric neurogenic divisions. This division mode dependence is phenocopied following conditional deletion of HR gene Brca2. Thus, distinct modes of NPC division have divergent requirements for Ino80-dependent HR DNA repair.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/genética , Proteína BRCA2/genética , Cromatina/química , Proteínas de Ligação a DNA/genética , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Reparo de DNA por Recombinação , ATPases Associadas a Diversas Atividades Celulares/deficiência , Animais , Apoptose/genética , Proteína BRCA2/deficiência , Divisão Celular , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , DNA/genética , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/deficiência , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Transgênicos , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Neocórtex/metabolismo , Células-Tronco Neurais/citologia , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
14.
Prostate ; 80(12): 1012-1023, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649013

RESUMO

BACKGROUND: Small cell neuroendocrine (NE) carcinomas of the prostate classically lose androgen receptor (AR) expression, may harbor loss of the RB1, TP53, and PTEN tumor suppressor genes, and are associated with a poor prognosis. However usual-type adenocarcinomas may also contain areas of NE differentiation, and in this context the molecular features and biological significance are less certain. METHODS: We examined the molecular phenotype and oncologic outcomes of primary prostate adenocarcinomas with ≥5% NE differentiation (≥5% chromogranin A-positive NE cells in any given tumor spot on tissue microarray) using three independent study sets: a set of tumors with paneth cell-like NE differentiation (n = 26), a retrospective case-cohort of intermediate- and high-risk patients enriched for adverse outcomes (n = 267), and primary tumors from a retrospective series of men with eventual castration-resistant metastatic prostate cancer (CRPC) treated with abiraterone or enzalutamide (n = 55). RESULTS: Benign NE cells expressed significantly lower quantified AR levels compared with paired benign luminal cells (P < .001). Similarly, paneth-like NE carcinoma cells or carcinoma cells expressing chromogranin A expressed significantly lower quantified AR levels than paired non-NE carcinoma cells (P < .001). Quantified ERG protein expression, was also lower in chromogranin A-labeled adenocarcinoma cells compared with unlabeled cells (P < .001) and tumors with NE differentiation showed lower gene expression scores for AR activity compared with those without. Despite evidence of lower AR signaling, adenocarcinomas with NE differentiation did not differ by prevalence of TP53 missense mutations, or PTEN or RB1 loss, compared with those without NE differentiation. Finally, NE differentiation was not associated with time to metastasis in intermediate- and high-risk patients (P = .6 on multivariate analysis), nor with progression-free survival in patients with CRPC treated with abiraterone or enzalutamide (P = .9). CONCLUSION: NE differentiation in usual-type primary prostate adenocarcinoma is a molecularly and clinically distinct form of lineage plasticity from that occurring in small cell NE carcinoma.


Assuntos
Células Neuroendócrinas/patologia , Tumores Neuroendócrinos/patologia , Neoplasias da Próstata/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Diferenciação Celular/fisiologia , Estudos de Coortes , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Células Neuroendócrinas/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/metabolismo , Estudos Retrospectivos , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
15.
Zhonghua Bing Li Xue Za Zhi ; 49(7): 715-720, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32610384

RESUMO

Objective: To evaluate the association of p53 protein expression with clinicopathological features and prognosis in esophageal spindle cell carcinoma. Methods: A total of 4 439 esophageal squamous cell carcinoma (ESCC) patients who underwent radical esophagectomy without neoadjuvant therapy between May 2010 and May 2019 were included. The HE slides and clinicopathological parameters were reviewed. Among these, there were 63 cases of esophageal spindle cell carcinoma; p53 protein expression was evaluated by immunohistochemistry (IHC) and its correlation with clinicopathological parameters and patients' outcome was analyzed. Results: The 63 esophageal spindle cell carcinoma accounted for 1.4% (63/4 439) of all ESCC. Of the 63 patients there were 55 males and 8 females, male to female ratio was 7∶1. The p53 protein mutation expression rate was 77.8% (49/63), including 14 cases with wild-type expression, 22 with nonsense mutation expression, and 27 with missense mutation expression. The concordance rate of p53 protein expression between carcinoma components and spindle cell components was 100%. Survival analysis showed that p53 protein mutation expression was significantly correlated with overall survival (OS, P=0.044), patients with p53 protein mutation expression had poorer OS. Conclusion: p53 protein expression is highly concordant in the squamous cell carcinoma components and spindle cell components of esophageal spindle cell carcinoma; its mutation expression is associated with poor outcome of the patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteína Supressora de Tumor p53/metabolismo , Biomarcadores Tumorais , Feminino , Humanos , Masculino , Prognóstico
16.
Chem Biol Interact ; 328: 109196, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32687844

RESUMO

Cancer metastasis and resistance for chemotherapeutic agent correlate with epithelial-mesenchymal transition (EMT), while ROS production also involves in the EMT process, However, how autophagy mediated ROS production affects EMT remains unclear. Previous study showed that DpdtC (2,2'-di-pyridylketone hydrazone dithiocarbamate) could induce ferritinophagy in HepG2 cell. To insight into more details that how ferritinophagy affects cellular feature, the SGC-7901and BGC-823 gastric cancer cell lines were used. Interestingly DpdtC treatment resulted in EMT inhibition and was ROS dependent. Similar situation occurred in TGF-ß1 induced EMT model, supporting that DpdtC was able to inhibit EMT. Next the ability of DpdtC in ferritinophagy induction was further evaluated. As expected, DpdtC induced ferritinophagy in the absence and presence of TGF-ß1. The correlation analysis revealed that an enhanced ferritinophagic flux contributed to the EMT inhibition. In addition, ferritinophagy triggers Fenton reaction, resulting in ROS production which give rise of p53 response, thus the role of p53 was further investigated. DpdtC treatment resulted in upregulation of p53, but, the addition of p53 inhibitor, PFT-α could significantly neutralize the action of DpdtC on ferritinophagy induction and EMT inhibition. Furthermore, autophagy inhibitors or NAC could counteract the action of DpdtC, indicating that ferrtinophagy-mediated ROS played an important role in the cellular events. In addition to upregulation of p53, its down-stream targets, AKT/mTor were also downregulated, supporting that DpdtC induced EMT inhibition was achieved through ferritinophagy-ROS vicious cycle mediated p53/AKT/mTor pathway. And the activation of ferritinophagic flux was the dominant driving force in action of DpdtC in gastric cancer cells.


Assuntos
Autofagia , Transição Epitelial-Mesenquimal , Ferritinas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/patologia , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Ditiocarb/análogos & derivados , Ditiocarb/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/metabolismo , Fator de Crescimento Transformador beta1/farmacologia
17.
Proc Natl Acad Sci U S A ; 117(30): 17808-17819, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661168

RESUMO

p53 is the most frequently mutated, well-studied tumor-suppressor gene, yet the molecular basis of the switch from p53-induced cell-cycle arrest to apoptosis remains poorly understood. Using a combination of transcriptomics and functional genomics, we unexpectedly identified a nodal role for the caspase-8 paralog and only human pseudo-caspase, FLIP(L), in regulating this switch. Moreover, we identify FLIP(L) as a direct p53 transcriptional target gene that is rapidly up-regulated in response to Nutlin-3A, an MDM2 inhibitor that potently activates p53. Genetically or pharmacologically inhibiting expression of FLIP(L) using siRNA or entinostat (a clinically relevant class-I HDAC inhibitor) efficiently promoted apoptosis in colorectal cancer cells in response to Nutlin-3A, which otherwise predominantly induced cell-cycle arrest. Enhanced apoptosis was also observed when entinostat was combined with clinically relevant, p53-activating chemotherapy in vitro, and this translated into enhanced in vivo efficacy. Mechanistically, FLIP(L) inhibited p53-induced apoptosis by blocking activation of caspase-8 by the TRAIL-R2/DR5 death receptor; notably, this activation was not dependent on receptor engagement by its ligand, TRAIL. In the absence of caspase-8, another of its paralogs, caspase-10 (also transcriptionally up-regulated by p53), induced apoptosis in Nutlin-3A-treated, FLIP(L)-depleted cells, albeit to a lesser extent than in caspase-8-proficient cells. FLIP(L) depletion also modulated transcription of canonical p53 target genes, suppressing p53-induced expression of the cell-cycle regulator p21 and enhancing p53-induced up-regulation of proapoptotic PUMA. Thus, even in the absence of caspase-8/10, FLIP(L) silencing promoted p53-induced apoptosis by enhancing PUMA expression. Thus, we report unexpected, therapeutically relevant roles for FLIP(L) in determining cell fate following p53 activation.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzamidas/farmacologia , Caspase 8/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Sinergismo Farmacológico , Regulação da Expressão Gênica , Humanos , Imidazóis/metabolismo , Modelos Biológicos , Piperazinas/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Piridinas/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteína Supressora de Tumor p53/genética
18.
Am J Chin Med ; 48(5): 1179-1202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32668972

RESUMO

Over-expression of calpains in tumor tissues can be associated with cancer progression. Thus, inhibition of calpain activity using specific inhibitors has become a novel approach to control tumor growth. In this study, the anticancer potential of cryptotanshinone in combination with calpain inhibitor had been investigated in colon cancer cells and tumor xenograft. Cryptotanshinone elicited an initial endoplasmic reticular (ER) stress response, whereas prolonged stress would result in the promotion of apoptosis. It was then discovered that cryptotanshinone could cause rapid and sustained increase in cytosolic calcium in colon cancer cells accompanied by early GRP78 overexpression, which could be attenuated by pre-treatment of the calcium chelator BAPTA-AM. Cryptotanshinone also facilitated an early increase in calpain activity, which could be blocked by BAPTA-AM or the calpain inhibitor PD150606. A dynamic interaction between GRP78 and calpain during the action of cryptotanshinone was unveiled. This together with the altered NF-[Formula: see text]B signaling could be abolished by calpain inhibitor. GRP78 knockdown increased the sensitivity of cancer cells to cryptotanshinone-evoked apoptosis and reduction of cancer cell colony formation. Such sensitization of drug action had been confirmed to be p53-dependent by using p53-mutated (HT-29) and p53-deficient (HCT116 p53-∕-) cells. The synergistic antitumor effect of cryptotanshinone and calpain inhibitor was further exhibited in vivo. Taken together, findings in this study exemplify a new chemotherapeutic regimen comprising cryptotanshinone and calpain inhibitor by regulation of calpain and calcium homeostasis. This has provided us with new insights in the search of a potential target-specific neoadjuvant therapy against colon cancer.


Assuntos
Antineoplásicos Fitogênicos , Apoptose/efeitos dos fármacos , Apoptose/genética , Cálcio/metabolismo , Calpaína/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Homeostase/efeitos dos fármacos , Fenantrenos/farmacologia , Fenantrenos/uso terapêutico , Fitoterapia , Proteína Supressora de Tumor p53/metabolismo , Animais , Calpaína/genética , Neoplasias do Colo/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Camundongos Nus , Células Tumorais Cultivadas
19.
Mol Immunol ; 125: 9-14, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32619931

RESUMO

MiR-483-3p is involved in the pathogenesis of acute myocardial infarctions, but its association with myocardial ischemia reperfusion (IR) remains mostly unknown. In this study, an in vitro model of myocardial IR injury was established by putting H9c2 cells into hypoxia reoxygenation (HR) treatment to explore the effects and possible mechanisms of miR-483-3p in myocardial IR injury. HR exposure resulted in increased miR-483-3p levels in H9c2 cells. MiR-483-3p was overexpressed or downregulated in H9c2 cells by transfection of miR-483-3p mimic or miR-483-3p inhibitor. In HR-treated H9c2 cells, MiR-483-3p mimics inhibited cell viability, promoted lactate dehydrogenase release, and increased apoptosis, but miR-483-3p inhibitors caused the opposite effects. MDM4 was verified to be the target mRNA of miR-483-3p and negatively modulated by miR-483-3p. MiR-483-3p inhibitor upregulated MDM4 and Bcl-2, but downregulated p53 and Bax in HR-treated H9c2 cells, whereas miR-483-3p overexpression produced the opposite effects.. Moreover, MDM4 siRNA transfection partially reversed the role of miR-483-3p inhibition in HR injury and p53 pathway inactivation of H9c2 cells. In summary, by targeting the MDM4/p53 pathway, miR-483-3p inhibition may alleviate myocardial HR injury. MiR-483-3p may be a potential therapeutic target of myocardial IR injury.


Assuntos
Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Técnicas In Vitro , Ratos
20.
Adv Cancer Res ; 148: 171-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32723563

RESUMO

Cancer is a complex disease with high incidence and mortality rates. The important role played by the tumor microenvironment in regulating oncogenesis, tumor growth, and metastasis is by now well accepted in the scientific community. SPARC is known to participate in tumor-stromal interactions and impact cancer growth in ambiguous ways, which either enhance or suppress cancer aggressiveness, in a context-dependent manner. p53 transcription factor, a well-established tumor suppressor, has been reported to promote tumor growth in certain situations, such as hypoxia, thus displaying a duality in its action. Although both proteins are being tested in clinical trials, the synergistic relation between them is yet to be explored in clinical practice. In this review, we address the controversial roles of SPARC and p53 as double agents in cancer, briefly summarizing the interaction found between these two molecules and its importance in cancer.


Assuntos
Neoplasias/metabolismo , Neoplasias/patologia , Osteonectina/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Humanos , Neoplasias/genética , Osteonectina/genética , Proteína Supressora de Tumor p53/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA