Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.357
Filtrar
1.
Sci Rep ; 12(1): 10337, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725923

RESUMO

DNA methylation can regulate the expression of tumour suppressor genes P16 and TP53, environmental factors, which are both important factors related to an increased risk and prognosis of oesophageal cancer (EC). However, the association between these two genes methylation status, as well as the effects of gene-environment interactions, EC risk remains unclear. A Hospital-based case-control study data were collected from 105 new EC cases and 108 controls. Promoter methylation status was investigated for P16 and TP53 genes using methylation-specific polymerase (MSP) chain reaction methods with SYBR green. Logistic and Cox regression models were used to analyse the association of P16 and TP53 promotor methylation status with EC risk and prognosis, respectively. Our results suggest P16, TP53 methylation significantly increased the risk of EC (OR = 5.24, 95% CI: 2.57-10.66, P < 0.001; OR = 3.38, 95% CI: 1.17-6.67, P < 0.001, respectively). In addition, P16 and TP53 promoter methylation status and the combined effects between environmental factors and its methylations in tissue were correlated with the EC risk and prognosis of EC patients. As a new biomarker, the methylation of P16 and TP53 can serve as a potential predictive biomarker of EC.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Metilação de DNA , Neoplasias Esofágicas , Proteína Supressora de Tumor p53 , Estudos de Casos e Controles , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/genética , Humanos , Prognóstico , Regiões Promotoras Genéticas , Tailândia/epidemiologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
2.
Oncogene ; 41(25): 3423-3432, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35577980

RESUMO

Studies have shown that Nrf2E79Q/+ is one of the most common mutations found in human tumors. To elucidate how this genetic change contributes to lung cancer, we compared lung tumor development in a genetically-engineered mouse model (GEMM) with dual Trp53/p16 loss, the most common mutations found in human lung tumors, in the presence or absence of Nrf2E79Q/+. Trp53/p16-deficient mice developed combined-small cell lung cancer (C-SCLC), a mixture of pure-SCLC (P-SCLC) and large cell neuroendocrine carcinoma. Mice possessing the LSL-Nrf2E79Q mutation showed no difference in the incidence or latency of C-SCLC compared with Nrf2+/+ mice. However, these tumors did not express NRF2 despite Cre-induced recombination of the LSL-Nrf2E79Q allele. Trp53/p16-deficient mice also developed P-SCLC, where activation of the NRF2E79Q mutation associated with a higher incidence of this tumor type. All C-SCLCs and P-SCLCs were positive for NE-markers, NKX1-2 (a lung cancer marker) and negative for P63 (a squamous cell marker), while only P-SCLC expressed NRF2 by immunohistochemistry. Analysis of a consensus NRF2 pathway signature in human NE+-lung tumors showed variable activation of NRF2 signaling. Our study characterizes the first GEMM that develops C-SCLC, a poorly-studied human cancer and implicates a role for NRF2 activation in SCLC development.


Assuntos
Carcinoma Neuroendócrino , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Carcinoma Neuroendócrino/patologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Incidência , Neoplasias Pulmonares/patologia , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética
3.
Aging (Albany NY) ; 14(10): 4281-4304, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35619220

RESUMO

Aging impairs organismal homeostasis leading to multiple pathologies. Yet, the mechanisms and molecular intermediates involved are largely unknown. Here, we report that aged aryl hydrocarbon receptor-null mice (AhR-/-) had exacerbated cellular senescence and more liver progenitor cells. Senescence-associated markers ß-galactosidase (SA-ß-Gal), p16Ink4a and p21Cip1 and genes encoding senescence-associated secretory phenotype (SASP) factors TNF and IL1 were overexpressed in aged AhR-/- livers. Chromatin immunoprecipitation showed that AhR binding to those gene promoters repressed their expression, thus adjusting physiological levels in AhR+/+ livers. MCP-2, MMP12 and FGF secreted by senescent cells were overproduced in aged AhR-null livers. Supporting the relationship between senescence and stemness, liver progenitor cells were overrepresented in AhR-/- mice, probably contributing to increased hepatocarcinoma burden. These AhR roles are not liver-specific since adult and embryonic AhR-null fibroblasts underwent senescence in culture, overexpressing SA-ß-Gal, p16Ink4a and p21Cip1. Notably, depletion of senescent cells with the senolytic agent navitoclax restored expression of senescent markers in AhR-/- fibroblasts, whereas senescence induction by palbociclib induced an AhR-null-like phenotype in AhR+/+ fibroblasts. AhR levels were downregulated by senescence in mouse lungs but restored upon depletion of p16Ink4a-expressing senescent cells. Thus, AhR restricts age-induced senescence associated to a differentiated phenotype eventually inducing resistance to liver tumorigenesis.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Receptores de Hidrocarboneto Arílico , Envelhecimento/metabolismo , Animais , Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Fibroblastos/metabolismo , Fígado/metabolismo , Camundongos , Receptores de Hidrocarboneto Arílico/genética
4.
Exp Gerontol ; 163: 111800, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35398171

RESUMO

With a rise in the need to develop anti-aging drugs, a growing number of in vivo studies evaluating the efficacy of potential drug candidates have used doxorubicin-induced aging mice. However, changes in the biomarkers of senescent cells have not been reported in detail in these animals. To lay a foundation for the use of doxorubicin-induced aging mice, we examined the biomarkers of hepatic and renal senescent cells in these mice. We found that the 5 mg/kg doxorubicin dose is optimal to induce cellular senescence in mice. Subsequently, using this dose, we found that doxorubicin-induced an increase in senescence-associated ß-galactosidase (SA-ß-gal) positive cells in the kidney and lipofuscin accumulation in the liver. Some markers of senescent cells (p21WAF1/CIP1, p16INK4A, and γH2AX) were also significantly upregulated by doxorubicin and then counteracted by metformin treatment. These preliminary findings support the application of doxorubicin-induced aging mice as an animal model to evaluate the efficacy of anti-aging drug candidates.


Assuntos
Envelhecimento , Senescência Celular , Animais , Biomarcadores , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Doxorrubicina/farmacologia , Camundongos , beta-Galactosidase/metabolismo
5.
Aging Cell ; 21(5): e13602, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35363946

RESUMO

Cellular senescence, which is a major cause of tissue dysfunction with aging and multiple other conditions, is known to be triggered by p16Ink4a or p21Cip1 , but the relative contributions of each pathway toward inducing senescence are unclear. Here, we directly addressed this issue by first developing and validating a p21-ATTAC mouse with the p21Cip1 promoter driving a "suicide" transgene encoding an inducible caspase-8 which, upon induction, selectively kills p21Cip1 -expressing senescent cells. Next, we used the p21-ATTAC mouse and the established p16-INK-ATTAC mouse to directly compare the contributions of p21Cip1 versus p16Ink4a in driving cellular senescence in a condition where a tissue phenotype (bone loss and increased marrow adiposity) is clearly driven by cellular senescence-specifically, radiation-induced osteoporosis. Using RNA in situ hybridization, we confirmed the reduction in radiation-induced p21Cip1 - or p16Ink4a -driven transcripts following senescent cell clearance in both models. However, only clearance of p21Cip1 +, but not p16Ink4a +, senescent cells prevented both radiation-induced osteoporosis and increased marrow adiposity. Reduction in senescent cells with dysfunctional telomeres following clearance of p21Cip1 +, but not p16Ink4a +, senescent cells also reduced several of the radiation-induced pro-inflammatory senescence-associated secretory phenotype factors. Thus, by directly comparing senescent cell clearance using two parallel genetic models, we demonstrate that radiation-induced osteoporosis is driven predominantly by p21Cip1 - rather than p16Ink4a -mediated cellular senescence. Further, this approach can be used to dissect the contributions of these pathways in other senescence-associated conditions, including aging across tissues.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Osteoporose , Adiposidade , Animais , Medula Óssea/metabolismo , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Camundongos , Obesidade , Osteoporose/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-35429664

RESUMO

Regulation of the cell cycle is an understudied response to oxygen deprivation among crustaceans. The virile crayfish, Orconectes virilis, is a freshwater crustacean that when challenged by environmental oxygen limitation undergoes metabolic rate depression (to ~30% of normal levels) and switches to anaerobic metabolism to generate energy. To understand how crayfish regulate the cell cycle in response to anoxia, key proteins involved in cell cycle control were analyzed in muscle and hepatopancreas. At the G1/S barrier, an overall upregulation of positive regulators of cell cycle progression was indicated by the responses of G1 cyclins (cyclin D and cyclin E) and Cyclin dependent kinases (CDK4, CDK6 and CDK2) under anoxia. Although the levels of Cyclin kinase inhibitors (CKIs) at this juncture were also upregulated (P15/16 and P21 (T145) in muscle and P16 (S152) in hepatopancreas), levels of a major regulator of this phase and driver to S-phase, E2F1, were significantly higher in both tissues in conjunction with deactivation of its inhibitor, Retinoblastoma (Rb) protein. At the G2/M barrier, expression profiles of the G2 cyclin B suggested cell cycle progression despite overall trend of higher activities of checkpoint kinases, (Chk1 (S317) and Chk2 (S19)), that also negatively regulate the cyclin B-CDK1 complex via CdC25C (cell division cycle 25) whose levels remained unchanged. Overall, the present study suggests continued cell cycle progression, albeit with potential deceleration, as indicated by checkpoint kinases and kinase inhibitor profiles that might play a role in protecting tissues from apoptotic damage under chronic anoxic stress.


Assuntos
Astacoidea , Proteínas de Ciclo Celular , Animais , Astacoidea/metabolismo , Ciclo Celular/fisiologia , Ciclina B/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Água Doce , Hepatopâncreas/metabolismo , Hipóxia/metabolismo , Músculos/metabolismo , Oxigênio/metabolismo , Fosforilação , Proteína do Retinoblastoma/metabolismo , Cauda
7.
Front Endocrinol (Lausanne) ; 13: 869414, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432205

RESUMO

Increased insulin resistance and impaired insulin secretion are significant characteristics manifested by patients with type 2 diabetes mellitus (T2DM). The degree and extent of these two features in T2DM vary among races and individuals. Insulin resistance is accelerated by obesity and is accompanied by accumulation of dysfunctional adipose tissues. In addition, dysfunction of pancreatic ß-cells impairs insulin secretion. T2DM is significantly affected by aging, as the ß-cell mass diminishes with age. Moreover, both obesity and hyperglycemia-related metabolic changes in developing diabetes are associated with accumulation of senescent cells in multiple organs, that is, organismal aging. Cellular senescence is defined as a state of irreversible cell cycle arrest with concomitant functional decline. It is caused by telomere shortening or senescence-inducing stress. Senescent cells secrete proinflammatory cytokines and chemokines, which is designated as the senescence-associated secretory phenotype (SASP), and this has a negative impact on adipose tissues and pancreatic ß-cells. Recent advances in aging research have suggested that senolysis, the removal of senescent cells, can be a promising therapeutic approach to prevent or improve aging-related diseases, including diabetes. The attenuation of a SASP may be beneficial, although the pathophysiological involvement of cellular senescence in diabetes is not fully understood. In the clinical application of senotherapy, tissue-context-dependent senescent cells are increasingly being recognized as an issue to be solved. Recent studies have observed highly heterogenic and complex senescent cell populations that serve distinct roles among tissues, various stages of disease, and different ages. For example, in high-fat-diet induced diabetes with obesity, mouse adipose tissues display accumulation of p21 Cip1-highly-expressing (p21 high) cells in the early stage, followed by increases in both p21 high and p16 INK4a-highly-expressing (p16 high) cells in the late stage. Interestingly, elimination of p21 high cells in visceral adipose tissue can prevent or improve insulin resistance in mice with obesity, while p16 high cell clearance is less effective in alleviating insulin resistance. Importantly, in immune-deficient mice transplanted with fat from obese patients, dasatinib plus quercetin, a senolytic cocktail that reduces the number of both p21 high and p16 high cells, improves both glucose tolerance and insulin resistance. On the other hand, in pancreatic ß cells, p16 high cells become increasingly predominant with age and development of diabetes. Consistently, elimination of p16 high cells in mice improves both glucose tolerance and glucose-induced insulin secretion. Moreover, a senolytic compound, the anti-Bcl-2 inhibitor ABT263 reduces p16 INK4a expression in islets and restores glucose tolerance in mice when combined with insulin receptor antagonist S961 treatment. In addition, efficacy of senotherapy in targeting mouse pancreatic ß cells has been validated not only in T2DM, but also in type 1 diabetes mellitus. Indeed, in non-obese diabetic mice, treatment with anti-Bcl-2 inhibitors, such as ABT199, eliminates senescent pancreatic ß cells, resulting in prevention of diabetes mellitus. These findings clearly indicate that features of diabetes are partly determined by which or where senescent cells reside in vivo, as adipose tissues and pancreatic ß cells are responsible for insulin resistance and insulin secretion, respectively. In this review, we summarize recent advances in understanding cellular senescence in adipose tissues and pancreatic ß cells in diabetes. We review the different potential molecular targets and distinctive senotherapeutic strategies in adipose tissues and pancreatic ß cells. We propose the novel concept of a dual-target tailored approach in senotherapy against diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Células Secretoras de Insulina , Tecido Adiposo/metabolismo , Animais , Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Humanos , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Camundongos , Obesidade/metabolismo
8.
Dev Comp Immunol ; 133: 104420, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35417735

RESUMO

Unlike most mammalian cell lines, fish cell lines are immortal and resistant to cellular senescence. Elevated expression of H-Ras contributes to the induction of senescence in a fish cell line, EPC, but is not sufficient to induce full senescence. Here, we focused on the absence of a p16INK4a/ARF locus in the fish genome, and investigated whether this might be a critical determinant of the resistance of EPC cells to full senescence. We found that transfected EPC cells constitutively overexpressing p16INK4a exhibited large size and flat morphology characteristic of prematurely senescent cells; the cells also showed p53-independent senescence-like growth arrest and senescence-associated ß-galactosidase (SA-ß-gal) activity. Furthermore, the mRNA levels of proinflammatory senescence-associated secretory phenotype (SASP) factors increased in EPC cells constitutively overexpressing p16INK4a. These results suggest that the lack of p16INK4a in the fish genome may be a critical determinant of senescence resistance in fish cell lines.


Assuntos
Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina , Animais , Linhagem Celular , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Peixes/genética , Peixes/metabolismo , Mamíferos , Fosforilcolina/análogos & derivados
9.
Anticancer Res ; 42(5): 2277-2288, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35489754

RESUMO

BACKGROUND/AIM: The TP53-signature is a multi-gene signature that can predict TP53 structural mutations. It has presented remarkable ability to predict the prognosis of early-stage breast cancer. However, some samples presented discordance with the signature status and structure status. We aimed to investigate whether the mRNA expression levels or copy number variation (CNV) of MDM2 and CDKN2A influence the TP53-signature-score, subtype classification, and prognosis prediction in TP53 wild-type, luminal type early-stage breast cancer samples. MATERIALS AND METHODS: We selected TP53 wild-type, luminal type early-stage breast cancer samples from The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohorts. Then, we analyzed the correlation between the TP53-signature-score and mRNA expression levels or CNV of MDM2 and CDKN2A. RESULTS: The samples with MDM2 copy number (CN) amplification or those with CDKN2A CN deep deletion presented higher TP53-signature-score. Moreover, samples with MDM2 CN amplification or those with CDKN2A CN deep deletion had more characteristics of the luminal B type. In addition, they showed lower estrogen response early score, which correlated with response to endocrine therapy in breast cancer. However, MDM2 and CDKN2A mRNA expression did not present the same tendency. Furthermore, samples with MDM2 CN amplification or those with CDKN2A CN deep deletion had a worse prognosis in METABRIC cohort. CONCLUSION: The MDM2 or CDKN2A CNV may be useful for classifying subtypes and predicting prognosis more accurately in TP53 wild-type, luminal type early-stage breast cancer patients.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Variações do Número de Cópias de DNA , Feminino , Genes p16 , Humanos , Prognóstico , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , RNA Mensageiro/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35269619

RESUMO

Endometriosis causes immunological and cellular alterations. Endometriosis lesions have lower levels of lamin b1 than the endometrium. Moreover, high levels of pro-inflammatory markers are observed in the peritoneal fluid, follicular fluid, and serum in endometriosis lesions. Thus, we hypothesized that the accumulation of senescent cells in endometriosis tissues would facilitate endometriosis maintenance in an inflammatory microenvironment. To study senescent cell markers and the senescence-associated secretory phenotype (SASP) in endometriosis lesions, we conducted a cross-sectional study with 27 patients undergoing video laparoscopy for endometriosis resection and 19 patients without endometriosis. Endometriosis lesions were collected from patients with endometriosis, while eutopic endometrium was collected from patients both with and without endometriosis. Tissues were evaluated for senescence markers (p16Ink4a, lamin b1, and IL-1ß) and interleukin concentrations. The expression of p16Ink4a increased in lesions compared to that in eutopic endometrium from endometriosis patients in the secretory phase. In the proliferative phase, lesions exhibited lower lamin b1 expression but higher IL-4 expression than the eutopic endometrium. Further, IL-1ß levels were higher in the lesions than in the eutopic endometrium in both the secretory and proliferative phases. We believe that our findings may provide targets for better therapeutic interventions to alleviate the symptoms of endometriosis.


Assuntos
Endometriose , Interleucina-1beta/metabolismo , Biomarcadores/metabolismo , Senescência Celular , Estudos Transversais , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Endometriose/patologia , Endométrio/metabolismo , Feminino , Humanos , Lamina Tipo B
11.
Tissue Cell ; 76: 101765, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35227974

RESUMO

Cartilage stem/progenitor cells (CSPCs) was recently isolated and identified from the cartilage tissue. CSPCs is essential for repair and regeneration of cartilage in osteoarthritis (OA). Aging is a primary risk factor for cartilage damage and joint OA. Although studies have confirmed the link between cell aging and OA, the underlying molecular mechanisms regulating CSPCs aging are not fully understood. In this study, we investigated the role of Pin1 in the aging of rat knee joint CSPCs. We isolated CSPCs from rat knee joints and demonstrated that, in long-term in vitro culture, Pin1 protein levels are significantly reduced. At the same time, expression of the senescence-related ß-galactosidase and the senescence marker p16INK4A were markedly elevated. In addition, Pin1 overexpression reversed the progression of cellular senescence, as evidenced by the down-regulation of senescence-related ß-galactosidase, increased EdU positive cells and diminished levels of p16INK4A. In contrast, Pin1 siRNA incorporation promoted CSPCs senescence. In addition, we also observed the distribution of cell cycles through flow cytometry and revealed that Pin1 deficiency results in cell cycle arrest in the G1 phase, suggesting severe lack of proliferation ability, a sign of cellular senescence. Collectively, these results validated that Pin1 is an essential regulator of CSPCs aging.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Cartilagem Articular , Osteoartrite , Células-Tronco , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Senescência Celular/fisiologia , Condrócitos/citologia , Condrócitos/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Ratos , Células-Tronco/citologia , Células-Tronco/metabolismo , beta-Galactosidase/metabolismo
12.
J Tissue Eng Regen Med ; 16(6): 550-558, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35319825

RESUMO

Chronic ischemia triggers senescence in renal tubules and at least partly mediates kidney dysfunction and damage through a p16Ink4a -related mechanism. We previously showed that mesenchymal stromal/stem cells (MSCs) delivered systemically do not effectively decrease cellular senescence in stenotic murine kidneys. We hypothesized that selective MSC targeting to injured kidneys using an anti-KIM1 antibody (KIM-MSC) coating would enhance their ability to abrogate cellular senescence in murine renal artery stenosis (RAS). KIM-MSC were injected into transgenic INK-ATTAC mice, which are amenable for selective eradication of p16Ink4a+ cells, 4 weeks after induction of unilateral RAS. To determine whether KIM-MSC abolish p16Ink4a -dependent cellular senescence, selective clearance of p16Ink4a+ cells was induced in a subgroup of RAS mice using AP20187 over 3 weeks prior to KIM-MSC injection. Two weeks after KIM-MSC aortic injection, renal senescence, function, and tissue damage were assessed. KIM-MSC delivery decreased gene expression of senescence and senescence-associated secretory phenotype factors, and improved micro-MRI-derived stenotic-kidney glomerular filtration rate and perfusion. Renal fibrosis and tubular injury also improved after KIM-MSC treatment. Yet, their efficacy was slightly augmented by prior elimination of p16Ink4a+ senescent cells. Therefore, selective targeting of MSC to the injured kidney markedly improves their senolytic potency in murine RAS, despite incomplete eradication of p16+ cells. KIM-MSC may constitute a useful therapeutic strategy in chronic renal ischemic injury.


Assuntos
Células-Tronco Mesenquimais , Obstrução da Artéria Renal , Animais , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Isquemia/metabolismo , Rim/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Transgênicos , Obstrução da Artéria Renal/metabolismo
13.
Mol Cancer ; 21(1): 89, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35354467

RESUMO

BACKGROUND: Frequent truncation mutations of the histone lysine N-methyltransferase KMT2C have been detected by whole exome sequencing studies in various cancers, including malignancies of the prostate. However, the biological consequences of these alterations in prostate cancer have not yet been elucidated. METHODS: To investigate the functional effects of these mutations, we deleted the C-terminal catalytic core motif of Kmt2c specifically in mouse prostate epithelium. We analysed the effect of Kmt2c SET domain deletion in a Pten-deficient PCa mouse model in vivo and of truncation mutations of KMT2C in a large number of prostate cancer patients. RESULTS: We show here for the first time that impaired KMT2C methyltransferase activity drives proliferation and PIN formation and, when combined with loss of the tumour suppressor PTEN, triggers loss of senescence, metastatic dissemination and dramatically reduces life expectancy. In Kmt2c-mutated tumours we show enrichment of proliferative MYC gene signatures and loss of expression of the cell cycle repressor p16INK4A. In addition, we observe a striking reduction in disease-free survival of patients with KMT2C-mutated prostate cancer. CONCLUSIONS: We identified truncating events of KMT2C as drivers of proliferation and PIN formation. Loss of PTEN and KMT2C in prostate cancer results in loss of senescence, metastatic dissemination and reduced life expectancy. Our data demonstrate the prognostic significance of KMT2C mutation status in prostate cancer patients. Inhibition of the MYC signalling axis may be a viable treatment option for patients with KMT2C truncations and therefore poor prognosis.


Assuntos
Metiltransferases , Neoplasias da Próstata , Animais , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Proteínas de Ligação a DNA/fisiologia , Humanos , Masculino , Metiltransferases/genética , Camundongos , Mutação , Neoplasias da Próstata/metabolismo , Sequenciamento Completo do Exoma
14.
Stem Cell Res ; 60: 102694, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35131736

RESUMO

p15INK4b (cyclin-dependent kinase inhibitor 2B, CDKN2B, p15), a cyclin-dependent kinase inhibitor (CKI) belonging to the INK4 family, plays an important role in hematopoiesis. Its expression level was positively related to the blockage effects of RUNX1b at the early stage. Experiments using human embryonic stem cell (hESC) lines with inducible p15 expression suggested that p15 overexpression can significantly decrease the proportion of KDR+ cells in S and G2-M stages 4 days after induction from day 0. Moreover, p15 overexpression from the early stage can decrease production of CD34highCD43- cells and their derivative populations, but not CD34lowCD43- cells. These effects were weakened if induction was delayed and disappeared if induction started after day 6. All these effects were counteracted by inhibition of TGF-ß signaling. TGF-ß1 stimulation elicited similar effects as p15 overexpression. RUNX1 overexpression and activation of the TGF-ß signaling pathway upregulate the expression of p15, which is partially responsible for blockade of hematopoiesis and relevant to a change in the cell cycle status. However, it is possible that other mechanisms are involved in the regulation of hematopoiesis.


Assuntos
Proteínas de Ciclo Celular , Subunidade alfa 2 de Fator de Ligação ao Core , Ciclo Celular , Pontos de Checagem do Ciclo Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Hematopoese , Humanos , Fator de Crescimento Transformador beta/metabolismo , Proteínas Supressoras de Tumor
15.
Nat Commun ; 13(1): 659, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115489

RESUMO

Kinase signaling fuels growth of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Yet its role in leukemia initiation is unclear and has not been shown in primary human hematopoietic cells. We previously described activating mutations in interleukin-7 receptor alpha (IL7RA) in poor-prognosis "ph-like" BCP-ALL. Here we show that expression of activated mutant IL7RA in human CD34+ hematopoietic stem and progenitor cells induces a preleukemic state in transplanted immunodeficient NOD/LtSz-scid IL2Rγnull mice, characterized by persistence of self-renewing Pro-B cells with non-productive V(D)J gene rearrangements. Preleukemic CD34+CD10highCD19+ cells evolve into BCP-ALL with spontaneously acquired Cyclin Dependent Kinase Inhibitor 2 A (CDKN2A) deletions, as commonly observed in primary human BCP-ALL. CRISPR mediated gene silencing of CDKN2A in primary human CD34+ cells transduced with activated IL7RA results in robust development of BCP-ALLs in-vivo. Thus, we demonstrate that constitutive activation of IL7RA can initiate preleukemia in primary human hematopoietic progenitors and cooperates with CDKN2A silencing in progression into BCP-ALL.


Assuntos
Subunidade alfa de Receptor de Interleucina-7/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Células Precursoras de Linfócitos B/imunologia , Transdução de Sinais/imunologia , Animais , Antígenos CD34/genética , Antígenos CD34/imunologia , Antígenos CD34/metabolismo , Sequência de Bases , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/imunologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Expressão Gênica/imunologia , Humanos , Subunidade alfa de Receptor de Interleucina-7/genética , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Células Precursoras de Linfócitos B/metabolismo , RNA-Seq/métodos , Receptores de Citocinas/genética , Receptores de Citocinas/imunologia , Receptores de Citocinas/metabolismo , Transdução de Sinais/genética , Análise de Célula Única/métodos , Transplante Heterólogo
16.
Neuroscience ; 488: 1-9, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35217122

RESUMO

Chronic macrophage activation was implicated as one of the main culprits for chronical, low-grade inflammation which significantly contributes to development of age-related diseases. Microglia as the brain macrophages have been recently implicated as key players in neuroinflammation and neurodegeneration in the aged brain. Microglial cell functions are indispensable in early development, however, activation or senescence of microglia in aging cells may be detrimental. Depletion of microglia using genetical or pharmacological approaches leads to opposite results regarding effects on brain cognition. In this study we pharmacologically depleted microglia using orally delivered low and high doses of the CSF1R inhibitor PLX5622 and assessed the expression levels of known inflammation markers (TNF-α, IL1-ß, IL-6, IL-10), glia markers (Iba-1 and Gfap) and specific senescence marker p16Ink4a in the aged murine brain. Our results indicate that treatment with low and high doses of PLX5622 leads to a dose-dependent depletion of microglial cells with similar levels in young and aged mice. We also show that treatment with low and high PLX5622 differentially affected cytokine levels in young and old brains. By using low doses we could achieve reduction in inflammation circumventing the astrocyte activation. Removal of microglia cells led to decreased expression of the senescence marker p16Ink4a in the aged brain, indicating a relevant contribution of these cells to the expression of this marker and their senescent status in the healthy aging brain. Our results indicate that increased and detrimental brain inflammation in aged murine brain can be impaired by selectively reducing the microglial cell population.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Microglia , Animais , Encéfalo/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/farmacologia , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Microglia/metabolismo
17.
Cells ; 11(3)2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35159350

RESUMO

A plethora of factors have been attributed to underly aging, including oxidative stress, telomere shortening and cellular senescence. Several studies have shown a significant role of the cyclin-dependent kinase inhibitor p16ink4a in senescence and aging. However, its expression in development has been less well documented. Therefore, to further clarify a potential role of p16 in development and aging, we conducted a developmental expression study of p16, as well as of p19ARF and p21, and investigated their expression on the RNA level in brain, heart, liver, and kidney of mice at embryonic, postnatal, adult, and old ages. P16 expression was further assessed on the protein level by immunohistochemistry. Expression of p16 was highly dynamic in all organs in embryonic and postnatal stages and increased dramatically in old mice. Expression of p19 and p21 was less variable and increased to a moderate extent at old age. In addition, we observed a predominant expression of p16 mRNA and protein in liver endothelial cells versus non-endothelial cells of old mice, which suggests a functional role specifically in liver endothelium of old subjects. Thus, p16 dynamic spatiotemporal expression might implicate p16 in developmental and physiological processes in addition to its well-known function in the build-up of senescence.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Células Endoteliais , Envelhecimento/metabolismo , Animais , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Células Endoteliais/metabolismo , Humanos , Camundongos , RNA Mensageiro/genética
18.
Biochem Biophys Res Commun ; 599: 43-50, 2022 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-35168063

RESUMO

The cyclin-dependent kinase inhibitor p16Ink4a plays a central role in cellular senescence in vitro. Although previous studies suggested cellular senescence is integrated in the systemic mechanisms of organismal aging, the localization and the dynamics of p16Ink4a in tissues remain poorly understood, which hinders uncovering the role of p16Ink4a under the in vivo context. One of the reasons is due to the lack of reliable reagents; as we also demonstrate here that commonly used antibodies raised against human p16INK4A barely recognize its murine ortholog. Here we generated a mouse model, in which the endogenous p16Ink4a is HA-tagged at its N-terminus, to explore the protein expression of p16Ink4a at the organismal level. p16Ink4a was induced at the protein level along the course of senescence in primary embryonic fibroblasts derived from the mice, consistently to its transcriptional level. Remarkably, however, p16Ink4a was not detected in the tissues of the mice exposed to pro-senescence conditions including genotoxic stress and activation of oncogenic signaling pathways, indicating that there is only subtle p16Ink4a proteins induced. These results in our mouse model highlight the need for caution in evaluating p16Ink4a protein expression in vivo.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Animais , Reações Cruzadas , Inibidor p16 de Quinase Dependente de Ciclina/imunologia , Dano ao DNA , Éxons , Fígado/metabolismo , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Células NIH 3T3
19.
Biol Open ; 11(2)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34994382

RESUMO

Fibroblasts are quiescent and tumor suppressive in nature but become activated in wound healing and cancer. The response of fibroblasts to cellular stress has not been extensively investigated, however the p53 tumor suppressor has been shown to be activated in fibroblasts during nutrient deprivation. Since the p19 Alternative reading frame (p19Arf) tumor suppressor is a key regulator of p53 activation during oncogenic stress, we investigated the role of p19Arf in fibroblasts during nutrient deprivation. Here, we show that prolonged leucine deprivation results in increased expression and nuclear localization of p19Arf, triggering apoptosis in primary murine adult lung fibroblasts (ALFs). In contrast, the absence of p19Arf during long-term leucine deprivation resulted in increased ALF proliferation, migration and survival through upregulation of the Integrated Stress Response pathway and increased autophagic flux. Our data implicates a new role for p19Arf in response to nutrient deprivation. This article has an associated First Person interview with the first author of the paper.


Assuntos
Proteína Supressora de Tumor p14ARF , Proteína Supressora de Tumor p53 , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Fibroblastos/metabolismo , Humanos , Leucina/metabolismo , Camundongos , Proteína Supressora de Tumor p14ARF/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
20.
Comput Math Methods Med ; 2022: 5113447, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35047055

RESUMO

BACKGROUND: One of the most usual gynecological state of tumor is ovarian cancer and is a major reason of gynecological tumor-related global mortality rate. There have been multiple risk elements related to ovarian cancer like the background of past cases associated with breast cancer or ovarian cancer, or excessive body weight issues, case history of smoking, and untimely menstruation or menopause. Because of unclear expressions, more than 70% of the ovarian cancer patient cases are determined during the early stage. Material and Methods. GSE38666, GSE40595, and GSE66957 were the three microarray datasets which were analyzed using GEO2R for screening the differentially expressed genes. GO, Kyoto Encyclopedia of Genes, and protein expression studies were performed for analysis of hub genes. Then, survival analysis was performed for all the hub genes. RESULTS: From the dataset, a total of 199 differentially expressed genes (DEGs) were identified. Through the KEGG pathway study, it was noted that the DEGs are mainly linked with the AGE-RAGE signaling pathway, central carbon metabolism, and human papillomavirus infection. The survival analysis showed 4 highly expressed hub genes COL4A1, SDC1, CDKN2A, and TOP2A which correlated with overall survival in ovarian cancer patients. Moreover, the expression of the 4 hub genes was validated by the GEPIA database and the Human Protein Atlas. CONCLUSION: The results have shown that all 4 hub genes were found to be upregulated in ovarian cancer tissues which predict poor prognosis in patients with ovarian cancer.


Assuntos
Biomarcadores Tumorais/genética , Redes Reguladoras de Genes , Neoplasias Ovarianas/genética , Biomarcadores Tumorais/metabolismo , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Biologia Computacional , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Ovarianas/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Prognóstico , Mapas de Interação de Proteínas/genética , Sindecana-1/genética , Sindecana-1/metabolismo , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...