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1.
J Cancer Res Clin Oncol ; 147(4): 987-1006, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33547489

RESUMO

BACKGROUND: Greater than half of cancer patients experience radiation therapy, for both radical and palliative objectives. It is well known that researches on radiation response mechanisms are conducive to improve the efficacy of cancer radiotherapy. p21 was initially identified as a widespread inhibitor of cyclin-dependent kinases, transcriptionally modulated by p53 and a marker of cellular senescence. It was once considered that p21 acts as a tumour suppressor mainly to restrain cell cycle progression, thereby resulting in growth suppression. With the deepening researches on p21, p21 has been found to regulate radiation responses via participating in multiple cellular processes, including cell cycle arrest, apoptosis, DNA repair, senescence and autophagy. Hence, a comprehensive summary of the p21's functions in radiation response will provide a new perspective for radiotherapy against cancer. METHODS: We summarize the recent pertinent literature from various electronic databases, including PubMed and analyzed several datasets from Gene Expression Omnibus database. This review discusses how p21 influences the effect of cancer radiotherapy via involving in multiple signaling pathways and expounds the feasibility, barrier and risks of using p21 as a biomarker as well as a therapeutic target of radiotherapy. CONCLUSION: p21's complicated and important functions in cancer radiotherapy make it a promising therapeutic target. Besides, more thorough insights of p21 are needed to make it a safe therapeutic target.


Assuntos
Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias/radioterapia , Radiação Ionizante , Animais , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais
2.
Gene ; 782: 145537, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33636294

RESUMO

Detection of TCGA data revealed that WIPI1 is highly expressed in osteosarcoma cells. So we explore the mechanisms of WIPI1 affecting the proliferation of osteosarcoma cells through Affymetrix microarray analysis. Functional analysis of differentially expressed genes shows that the classical signaling pathways affecting tumor formation and development have changed significantly. By fitting analysis, it is speculated that the WIPI1 may function in the direction of osteosarcoma by regulating the expression of multiple cell cycle-related genes such as CDKN1A, CDK4 and CCND1. Therefore, the key genes are selected for RT-PCR and Western-blot verification. Combined with flow and other means, WIPI1 may affect the cell cycle and the osteosarcoma by regulating the expression of CDKN1A, CDK4 and CCND1. To verify the results, the effect of WIPI1 on cell proliferation was quantified by MTT, cell counts and nude mouse tumorigenicity assay. The results showed that WIPI1 promotes osteosarcoma cell proliferation.


Assuntos
Proteínas Relacionadas à Autofagia/genética , Neoplasias Ósseas/genética , Proliferação de Células/genética , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Proteínas de Membrana/genética , Osteossarcoma/genética , Animais , Proteínas Relacionadas à Autofagia/fisiologia , Neoplasias Ósseas/patologia , Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos , Células HEK293 , Humanos , Lentivirus/genética , Proteínas de Membrana/fisiologia , Camundongos Nus , Análise de Sequência com Séries de Oligonucleotídeos , Osteossarcoma/patologia , Software , Transcriptoma
3.
Int J Mol Sci ; 22(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466733

RESUMO

RNA-binding proteins are frequently dysregulated in human cancer and able to modulate tumor cell proliferation as well as tumor metastasis through post-transcriptional regulation on target genes. Abnormal DNA damage response and repair mechanism are closely related to genome instability and cell transformation. Here, we explore the function of the RNA-binding protein muscleblind-like splicing regulator 2 (MBNL2) on tumor cell proliferation and DNA damage response. Transcriptome and gene expression analysis show that the PI3K/AKT pathway is enriched in MBNL2-depleted cells, and the expression of cyclin-dependent kinase inhibitor 1A (p21CDKN1A) is significantly affected after MBNL2 depletion. MBNL2 modulates the mRNA and protein levels of p21, which is independent of its canonical transcription factor p53. Moreover, depletion of MBNL2 increases the phosphorylation levels of checkpoint kinase 1 (Chk1) serine 345 (S345) and DNA damage response, and the effect of MBNL2 on DNA damage response is p21-dependent. MBNL2 would further alter tumor cell fate after DNA damage, MBNL2 knockdown inhibiting DNA damage repair and DNA damage-induced senescence, but promoting DNA damage-induced apoptosis.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/genética , Dano ao DNA , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a RNA/genética , Apoptose/genética , Proliferação de Células/genética , Quinase 1 do Ponto de Checagem/genética , Quinase 1 do Ponto de Checagem/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células HCT116 , Células HeLa , Humanos , Fosforilação , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Int J Mol Sci ; 22(2)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33478005

RESUMO

The objective was to investigate the anti-cancer effects and underlying molecular mechanisms of cytostasis which were activated by an anti-microtubule drug, ABT-751, in two urinary bladder urothelial carcinoma (UBUC)-derived cell lines, BFTC905 and J82, with distinct genetic backgrounds. A series of in vitro assays demonstrated that ABT-751 induced G2/M cell cycle arrest, decreased cell number in the S phase of the cell cycle and suppressed colony formation/independent cell growth, accompanied with alterations of the protein levels of several cell cycle regulators. In addition, ABT-751 treatment significantly hurdled cell migration and invasion along with the regulation of epithelial-mesenchymal transition-related proteins. ABT-751 triggered autophagy and apoptosis, downregulated the mechanistic target of rapamycin kinase (MTOR) and upregulated several pro-apoptotic proteins that are involved in extrinsic and intrinsic apoptotic pathways. Inhibition of autophagosome and autolysosome enhanced apoptosis was also observed. Through the inhibition of the NFκB signaling pathway, ABT-751 suppressed S-phase kinase associated protein 2 (SKP2) transcription and subsequent translation by downregulation of active/phospho-AKT serine/threonine kinase 1 (AKT1), component of inhibitor of nuclear factor kappa B kinase complex (CHUK), NFKB inhibitor alpha (NFKBIA), nuclear RELA proto-oncogene, NFκB subunit (RELA) and maintained a strong interaction between NFKBIA and RELA to prevent RELA nuclear translocation for SKP2 transcription. ABT-751 downregulated stable/phospho-SKP2 including pSKP2(S64) and pSKP2(S72), which targeted cyclin-dependent kinase inhibitors for degradation through the inactivation of AKT. Our results suggested that ABT-751 may act as an anti-cancer drug by inhibiting cell migration, invasion yet inducing cell cycle arrest, autophagy and apoptosis in distinct UBUC-derived cells. Particularly, the upstream molecular mechanism of its anticancer effects was identified as ABT-751-induced cytostasis through the inhibition of SKP2 at both transcriptional and post-translational levels to stabilize cyclin dependent kinase inhibitor 1A (CDKN1A) and CDKN1B proteins.


Assuntos
Carcinoma/tratamento farmacológico , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Proteínas Quinases Associadas a Fase S/genética , Transcrição Genética/efeitos dos fármacos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma/genética , Carcinoma/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fosfatidilinositol 3-Quinase/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases Associadas a Fase S/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Urotélio/efeitos dos fármacos , Urotélio/patologia
5.
Nucleic Acids Res ; 49(3): 1631-1646, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33444453

RESUMO

Mammalian circRNAs can influence different cellular processes by interacting with proteins and other nucleic acids. Here, we used ribonucleoprotein immunoprecipitation (RIP) analysis to identify systematically the circRNAs associated with the cancer-related protein AUF1. Among the circRNAs interacting with AUF1 in HeLa (human cervical carcinoma) cells, we focused on hsa_circ_0032434 (circPCNX), an abundant target of AUF1. Overexpression of circPCNX specifically interfered with the binding of AUF1 to p21 (CDKN1A) mRNA, thereby promoting p21 mRNA stability and elevating the production of p21, a major inhibitor of cell proliferation. Conversely, silencing circPCNX increased AUF1 binding to p21 mRNA, reducing p21 production and promoting cell division. Importantly, eliminating the AUF1-binding region of circPCNX abrogated the rise in p21 levels and rescued proliferation. Therefore, we propose that the interaction of circPCNX with AUF1 selectively prevents AUF1 binding to p21 mRNA, leading to enhanced p21 mRNA stability and p21 protein production, thereby suppressing cell growth.


Assuntos
Proliferação de Células/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Ribonucleoproteína Nuclear Heterogênea D0/metabolismo , RNA Circular/metabolismo , Regiões 3' não Traduzidas , Sítios de Ligação , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células HeLa , Humanos , RNA Circular/química , RNA Mensageiro/metabolismo
6.
Mol Med Rep ; 23(2): 1, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33325535

RESUMO

Burkitt lymphoma (BL) has a high mortality rate and its treatment is currently limited to chemotherapy combined with immunotherapy. The long non­coding RNA antisense non­coding RNA in the INK4 locus (ANRIL) has been identified as an oncogene that can regulate cell proliferation and apoptosis in multiple types of cancer. However, the function of ANRIL in BL remains unknown. The present study aimed to determine the effect of ANRIL on cell proliferation and apoptosis in BL. Reverse transcription­quantitative PCR was used to analyze the expression levels of ANRIL in BL cells. The effect of ANRIL knockdown on BL cells was determined using Cell Counting Kit­8, flow cytometric, western blotting, immunofluorescence staining and Hoechst staining assays. The results revealed that ANRIL silencing inhibited the proliferation and promoted the apoptosis of BL cells. In addition, the expression levels of cyclin D1, E2F transcription factor 1 and Bcl­2 were downregulated, while the expression levels of cyclin­dependent kinase inhibitor 1A, Bcl­2­associated X protein, cleaved­caspase­9/pro­caspase­9 and cleaved­caspase­3/pro­caspase­3 were upregulated. Furthermore, the knockdown of ANRIL activated the TGF­ß1 signaling pathway, as evidenced by the upregulated expression levels of TGF­ß1, phosphorylated (p)­SMAD2/3/SMAD2/3, p­SMAD1/SMAD1 and sphingosine­1­phosphate receptor 2. Moreover, the protective effect of ANRIL silencing in BL could be inhibited by the TGF­ß receptor type I/II dual inhibitor, LY2109761. In conclusion, the findings of the present study suggested that the knockdown of ANRIL may inhibit cell proliferation and promote cell apoptosis in BL by regulating the TGF­ß1 signaling pathway, which may provide a novel target for the treatment of BL.


Assuntos
Apoptose , Linfoma de Burkitt/genética , Proliferação de Células , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/fisiopatologia , Linhagem Celular Tumoral , Ciclina D1/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Fator de Transcrição E2F1/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Fator de Crescimento Transformador beta1/genética , Proteína X Associada a bcl-2/genética
7.
PLoS One ; 15(12): e0243499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326448

RESUMO

Excessive alcohol consumption is a risk factor associated with colorectal cancer; however, some epidemiological studies have reported that moderate alcohol consumption may not contribute additional risk or may provide a protective effect reducing colorectal cancer risk. Prior research highlights the importance of proliferation, differentiation, and apoptosis as parameters to consider when evaluating colonic cell growth and tumorigenesis. The present study investigated whether chronic low-to-moderate ethanol consumption altered these parameters of colonic cell growth and expression of related genes. Twenty-four nondeprived young adult (109 days old) and 24 nondeprived middle-aged (420 days old) Wistar rats were randomly assigned to an ethanol-exposed or a water control group (n = 12/group). The ethanol group was provided voluntary access to a 20% v/v ethanol solution on alternate days for 13 weeks. Colon tissues were collected for quantitative immunohistochemical analyses of cell proliferation, differentiation and apoptosis using Ki-67, goblet cell and TUNEL, respectively. Gene expression of cyclin D1 (Ccnd1), Cdk2, Cdk4, p21waf1/cip1 (Cdkn1a), E-cadherin (Cdh1) and p53 were determined by quantitative real-time polymerase chain reaction in colonic scraped mucosa. Ethanol treatment resulted in a lower cell proliferation index and proliferative zone, and lower Cdk2 expression in both age groups, as well as trends toward lower Ccnd1 and higher Cdkn1a expression. Cell differentiation was modestly but significantly reduced by ethanol treatment only in older animals. Overall, older rats showed decreases in apoptosis and gene expression of Cdk4, Cdh1, and p53 compared to younger rats, but there was no observed effect of ethanol exposure on these measures. These findings suggest that low-to-moderate ethanol consumption improves at least one notable parameter in colonic tumorigenesis (cell proliferation) and associated gene expression regardless of age, however, selectively decreased cell differentiation among older subjects.


Assuntos
Etanol/farmacologia , Expressão Gênica/efeitos dos fármacos , Envelhecimento , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colo/citologia , Colo/metabolismo , Colo/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Masculino , Ratos , Ratos Wistar , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
8.
J Toxicol Sci ; 45(11): 713-724, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132245

RESUMO

Acrylonitrile (AN), which is widely utilized in the manufacture of plastics, acrylamide, acrylic fibers, and resins, is also one of main components of cigarette smoke (CS). In this study, we examined the effects of AN on the cell viability and apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cell lines. A cell viability assay confirmed that AN decreased the cell proliferation of JEG-3 and BeWo cells in a dose-dependent manner. Additionally, Western blot assay revealed that protein expression of cyclin D and cyclin E decreased, while protein expression of p21 and p27 increased in response to AN treatment for 48 hr. The changes in reactive oxygen species (ROS) levels in JEG-3 and BeWo cells exposed to AN were also measured by a dichlorofluorescein diacetate (DCFH-DA) assay, which revealed that ROS levels increased in response to AN treatment for 48 hr. Moreover, western blot assay confirmed that AN treatment of JEG-3 and BeWo cells for 4 hr promoted the expression of phosphorylated eukaryotic initiation factor 2 alpha protein (p-eIF2α), C/EBP homologous protein (CHOP) and caspase 12, which are known to be involved in ROS-mediated endoplasmic reticulum stress (ER-stress)-related apoptosis. Overall, the protein expression of p53 and Bax (a pro-apoptosis marker) increased, while the expression of Bcl-xl (an anti-apoptotic marker) decreased and the number of apoptotic cells increased in response to AN treatment for 48 hr. Taken together, these results suggest that AN has the potential to induce apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cells by activating ROS.


Assuntos
Acrilonitrila/efeitos adversos , Acrilonitrila/toxicidade , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Coriocarcinoma/metabolismo , Coriocarcinoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Coriocarcinoma/fisiopatologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
9.
Cell Prolif ; 53(10): e12903, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32926483

RESUMO

OBJECTIVE: Dysregulation of the cell cycle is associated with the progression of malignant cancer, but its precise functional contribution is unknown. MATERIALS AND METHODS: The expression of EIF1AX in breast cancer tissues was detected by qRT-PCR and immunohistochemistry staining. Colony formation and tumour xenograft assays were used to examine the tumorigenesis-associated function of EIF1AX in vitro and in vivo. RNA-Seq analysis was used to select the downstream target genes of EIF1AX. Flow cytometry, ChIP and luciferase assays were used to investigate the molecular mechanisms by which EIF1AX regulates p21 in breast cancer cells. RESULTS: EIF1AX promoted breast cancer cell proliferation by promoting the G1/S cell cycle transition. A mechanistic investigation showed that EIF1AX inhibited the expression of p21, which is an essential cell cycle regulator. We identified that the transcriptional regulation of p21 by EIF1AX was p53-independent. Clinically, EIF1AX levels were significantly elevated in breast cancer tissues, and the high level of EIF1AX was associated with lower survival rates in breast cancer patients. CONCLUSIONS: Our results imply that EIF1AX may play a key role in the incidence and promotion of breast cancer and may, thus, serve as a valuable target for breast cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fator de Iniciação 1 em Eucariotos/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Fator de Iniciação 1 em Eucariotos/antagonistas & inibidores , Fator de Iniciação 1 em Eucariotos/genética , Feminino , Fase G1 , Humanos , Camundongos , Camundongos Nus , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fase S , Ativação Transcricional , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
10.
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
11.
Tumour Biol ; 42(9): 1010428320954735, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32873193

RESUMO

Acute myeloid leukemia is the most common form of acute leukemia in adults, constituting about 80% of cases. Although remarkable progress has been made in the therapeutic scenario for patients with acute myeloid leukemia, research and development of new and effective anticancer agents to improve patient outcome and minimize toxicity is needed. In this study, the antitumor activity of axolotl (AXO) Ambystoma mexicanum crude extract was assessed in vitro on the human acute myeloid leukemia HL-60 cell line. The anticancer activity was evaluated in terms of ability to influence proliferative activity, cell viability, cell cycle arrest, and differentiation. Moreover, gene expression analysis was performed to evaluate the genes involved in the regulation of these processes. The AXO crude extract exhibited antiproliferative but not cytotoxic activities on HL-60 cells, with cell cycle arrest in the G0/G1 phase. Furthermore, the AXO-treated HL-60 cells showed an increase in both the percentage of nitroblue tetrazolium positive cells and the expression of CD11b, whereas the proportion of CD14-positive cells did not change, suggesting that extract is able to induce differentiation toward the granulocytic lineage. Finally, the treatment with AXO extract caused upregulation of CEBPA, CEBPB, CEBPE, SPI1, CDKN1A, and CDKN2C, and downregulation of c-MYC. Our data clearly show the potential anticancer activity of Ambystoma mexicanum on HL-60 cells and suggest that it could help develop promising therapeutic agents for the treatment of acute myeloid leukemia.


Assuntos
Ambystoma mexicanum , Proliferação de Células/efeitos dos fármacos , Misturas Complexas/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p18/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proteínas Proto-Oncogênicas c-myc/genética
12.
Anticancer Res ; 40(10): 5631-5639, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988887

RESUMO

BACKGROUND/AIM: DNA damage response (DDR), wherein p21 is a cell fate determinant, is a potential cancer therapeutic target. Molecular expression during DDR was explored in ovarian clear-cell carcinoma (CCC). MATERIALS AND METHODS: CHK1, CHK2, TP53 and p21 expression in DDR was examined using immunostaining in surgical sections of CCC (n=22). Molecular alterations in two types of CCC cell lines, JHOC-5 and JHOC-9, were investigated using western blot analysis. RESULTS: Expression of DDR-associated molecules was noted in most patients. While high p21 expression was found in half of the patients, the remaining patients exhibited low p21 expression. Treatment with UC2288, a p21 inhibitor, attenuated proliferation of both cell lines, more prominently in JHOC-9, resulting in reduced viability and subsequent apoptosis. CONCLUSION: p21 Inhibitor induced cell death in cells with high p21 expression, suggesting that p21 suppression can be a therapeutic strategy to treat patients with CCC.


Assuntos
Quinase 1 do Ponto de Checagem/genética , Quinase do Ponto de Checagem 2/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Neoplasias Ovarianas/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Dano ao DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia
13.
Am J Physiol Endocrinol Metab ; 319(2): E447-E454, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32691630

RESUMO

The aim of the present study was to determine if the training status decreases inflammation, slows down senescence, and preserves telomere health in skeletal muscle in older compared with younger subjects, with a specific focus on satellite cells. Analyses were conducted on skeletal muscle and cultured satellite cells from vastus lateralis biopsies (n = 34) of male volunteers divided into four groups: young sedentary (YS), young trained cyclists (YT), old sedentary (OS), and old trained cyclists (OT). The senescence state and inflammatory profile were evaluated by telomere dysfunction-induced foci (TIF) quantification, senescence-associated ß-galactosidase (SA-ß-Gal) staining, and quantitative (q)RT-PCR. Independently of the endurance training status, TIF levels (+35%, P < 0.001) and the percentage of SA-ß-Gal-positive cells (+30%, P < 0.05) were higher in cultured satellite cells of older compared with younger subjects. p16 (4- to 5-fold) and p21 (2-fold) mRNA levels in skeletal muscle were higher with age but unchanged by the training status. Aging induced higher CD68 mRNA levels in human skeletal muscle (+102%, P = 0.009). Independently of age, both trained groups had lower IL-8 mRNA levels (-70%, P = 0.011) and tended to have lower TNF-α mRNA levels (-40%, P = 0.10) compared with the sedentary subjects. All together, we found that the endurance training status did not slow down senescence in skeletal muscle and satellite cells in older compared with younger subjects despite reduced inflammation in skeletal muscle. These findings highlight that the link between senescence and inflammation can be disrupted in skeletal muscle.


Assuntos
Envelhecimento/fisiologia , Treino Aeróbico , Inflamação/prevenção & controle , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Homeostase do Telômero/fisiologia , Idoso , Senescência Celular/genética , Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , Masculino , Músculo Esquelético/química , Músculo Esquelético/citologia , RNA Mensageiro/análise , Células Satélites de Músculo Esquelético/fisiologia , Células Satélites de Músculo Esquelético/ultraestrutura , Telômero/fisiologia , Telômero/ultraestrutura , Adulto Jovem , beta-Galactosidase/análise
14.
Oncogene ; 39(36): 5855-5866, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32616890

RESUMO

Epidermal squamous cell carcinoma (SCC) is a common and highly invasive form of cancer. SCC arises due to ultraviolet light exposure and is associated with increased expression of pro-cancer genes and reduced expression of cancer suppressors. Actin-Like Protein 6A (ACTL6A, BAF53a) is an important protein subunit of the SWI/SNF epigenetic chromatin regulatory complex. ACTL6A is elevated in cancer cells and has been implicated as a driver of cancer cell proliferation and tumor growth. In the present study, we show that ACTL6A drives SCC cell proliferation, spheroid formation, invasion and migration, and that these activities are markedly reduced by ACTL6A knockdown. We further show that ACTL6A expression is associated with reduced levels of the p21Cip1 cyclin-dependent kinase inhibitor and tumor suppressor protein. Molecular studies show that ACTL6A interacts with p53 DNA response elements in the p21Cip1 gene promoter to suppress p21Cip1 promoter activity and mRNA and protein level. Additional studies show that an increase in p21Cip1 expression in ACTL6A knockdown cells is required for suppression of the SCC cell phenotype, suggesting that p21Cip1 is a mediator of ACTL6A action. We further show that this regulation is p53 independent. These findings suggest that ACTL6A suppresses p21Cip1 promoter activity to reduce p21Cip1 protein as a mechanism to maintain the aggressive epidermal SCC phenotype.


Assuntos
Actinas/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Actinas/genética , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Epiderme/metabolismo , Epiderme/patologia , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Camundongos , Fenótipo , Regiões Promotoras Genéticas , Neoplasias Cutâneas/patologia , Ativação Transcricional , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Int J Nanomedicine ; 15: 1997-2010, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273698

RESUMO

Background: As one of the most widely produced engineered nanomaterials, titanium dioxide nanoparticles (nano-TiO2) are used in biomedicine and healthcare products, and as implant scaffolds; therefore, the toxic mechanism of nano-TiO2 has been extensively investigated with a view to guiding application. Three-dimensional (3D) spheroid models can simplify the complex physiological environment and mimic the in vivo architecture of tissues, which is optimal for the assessment of nano-TiO2 toxicity under ultraviolet A (UVA) irradiation. Methods and Results: In the present study, the toxicity of nano-TiO2 under UVA irradiation was investigated in 3D H22 spheroids cultured in fibrin gels. A significant reduction of approximately 25% in spheroid diameter was observed following treatment with 100 µg/mL nano-TiO2 under UVA irradiation after seven days of culture. Nano-TiO2 under UVA irradiation triggered the initiation of the TGF-ß/Smad signaling pathway, increasing the expression levels of TGF-ß1, Smad3, Cdkn1a, and Cdkn2b at both the mRNA and protein level, which resulted in cell cycle arrest in the G1 phase. In addition, nano-TiO2 under UVA irradiation also triggered the production of reactive oxygen species (ROS), which were shown to be involved in cell cycle regulation and the induction of TGF-ß1 expression. Conclusion: Nano-TiO2 under UVA irradiation induced cell cycle arrest in the G1 phase and the formation of smaller spheroids, which were associated with TGF-ß/Smad signaling pathway activation and ROS generation. These results reveal the toxic mechanism of nano-TiO2 under UVA irradiation, providing the possibility for 3D spheroid models to be used in nanotoxicology studies.


Assuntos
Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Nanopartículas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Titânio/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos da radiação , Camundongos , Nanopartículas/química , Proteína Smad3/genética , Proteína Smad3/metabolismo , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/efeitos da radiação , Raios Ultravioleta
16.
J Virol ; 94(12)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32269126

RESUMO

Human papillomavirus 16 (HPV16) E7 has long been known to stabilize the tumor suppressor TP53. However, the molecular mechanism of TP53 stabilization by HPV16 E7 has remained obscure, and this stabilization can occur independently of the E2F-regulated MDM2 inhibitor p14ARF Here, we report that the damage-induced noncoding (DINO) lncRNA (DINOL) is the "missing link" between HPV16 E7 and increased TP53 levels. DINO levels are decreased in cells where TP53 is inactivated, either by HPV16 E6, by expression of a dominant negative TP53 minigene, or by TP53 depletion. DINO levels are increased in HPV16 E7-expressing cells. HPV16 E7 causes increased DINO expression independently of RB1 degradation and E2F1 activation. Similar to what is seen with the adjacent CDKN1A locus, DINO expression is regulated by the histone demethylase KDM6A. DINO stabilizes TP53 in HPV16 E7-expressing cells, and as it is a TP53 transcriptional target, DINO levels further increase. As with expression of other oncogenes, such as adenovirus E1A or MYC, HPV16 E7-expressing cells are sensitized to cell death under conditions of metabolic stress, which in the case of E7 has been linked to TP53 activation. Consistent with earlier studies, we show that HPV16 E7-expressing keratinocytes are highly sensitive to metabolic stress induced by starvation or the antidiabetic drug metformin. Sensitivity of HPV16 E7-expressing cells to metabolic stress is rescued by DINO depletion. Moreover, DINO depletion decreases sensitivity to the DNA damage-inducing chemotherapy agent doxorubicin. This work identifies DINO as a critical mediator of TP53 stabilization and activation in HPV16 E7-expressing cells.IMPORTANCE Viral oncoproteins, including HPV16 E6 and E7, have been instrumental in elucidating the activities of cellular signaling networks, including those governed by the TP53 tumor suppressor. Our study demonstrates that the long noncoding RNA DINO is the long-sought missing link between HPV16 E7 and elevated TP53 levels. Importantly, the TP53-stabilizing DINO plays a critical role in the cell death response of HPV16 E7-expressing cells to metabolic stress or DNA damage.


Assuntos
Histona Desmetilases/genética , Interações Hospedeiro-Patógeno/genética , Proteínas E7 de Papillomavirus/genética , RNA Longo não Codificante/genética , Proteína Supressora de Tumor p53/genética , Antibióticos Antineoplásicos/farmacologia , Sobrevivência Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Doxorrubicina/farmacologia , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Regulação da Expressão Gênica , Histona Desmetilases/metabolismo , Papillomavirus Humano 16 , Humanos , Hipoglicemiantes/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/virologia , Metformina/farmacologia , Proteínas E7 de Papillomavirus/metabolismo , Cultura Primária de Células , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
17.
Sci Rep ; 10(1): 4888, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184434

RESUMO

Although fibrosis depicts a reparative mechanism, maladaptation of the heart due to excessive production of extracellular matrix accelerates cardiac dysfunction. The anthraquinone Rhein was examined for its anti-fibrotic potency to mitigate cardiac fibroblast-to-myofibroblast transition (FMT). Primary human ventricular cardiac fibroblasts were subjected to hypoxia and characterized with proteomics, transcriptomics and cell functional techniques. Knowledge based analyses of the omics data revealed a modulation of fibrosis-associated pathways and cell cycle due to Rhein administration during hypoxia, whereas p53 and p21 were identified as upstream regulators involved in the manifestation of cardiac fibroblast phenotypes. Mechanistically, Rhein acts inhibitory on HDAC classes I/II as enzymatic inhibitor. Rhein-mediated cellular effects were linked to the histone deacetylase (HDAC)-dependent protein stabilization of p53 under normoxic but not hypoxic conditions. Functionally, Rhein inhibited collagen contraction, indicating anti-fibrotic property in cardiac remodeling. This was accompanied by increased abundance of SMAD7, but not SMAD2/3, and consistently SMAD-specific E3 ubiquitin ligase SMURF2. In conclusion, this study identifies Rhein as a novel potent direct HDAC inhibitor that may contribute to the treatment of cardiac fibrosis as anti-fibrotic agent. As readily available drug with approved safety, Rhein constitutes a promising potential therapeutic approach in the supplemental and protective intervention of cardiac fibrosis.


Assuntos
Antraquinonas/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 2/antagonistas & inibidores , Adulto , Western Blotting , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Transcriptoma/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
18.
Sci Rep ; 10(1): 3808, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32123240

RESUMO

Urothelial carcinoma (UC) is a common disease causing significant morbidity and mortality as well as considerable costs for health systems. Extensive aberrant methylation of DNA is broadly documented in early UC, contributing to genetic instability, altered gene expression and tumor progression. However the triggers initiating aberrant methylation are unknown. Recently we discovered that several genes encoding key enzymes of methyl group and polyamine metabolism, including Ornithine Decarboxylase 1 (ODC1), are affected by DNA methylation in early stage UC. In this study, we investigated the hypothesis that these epigenetic alterations act in a feed-forward fashion to promote aberrant DNA methylation in UC. We demonstrate that siRNA-mediated knockdown of ODC1 expression elicits genome-wide LINE-1 demethylation, induction of LINE-1 transcripts and double-strand DNA breaks and decreases viability in primary cultured uroepithelial cells. Similarly, following siRNA-mediated knockdown of ODC1, UC cells undergo double-strand DNA breaks and apoptosis. Collectively, our findings provide evidence that ODC1 gene hypermethylation could be a starting point for the onset of genome-wide epigenetic aberrations in urothelial carcinogenesis. Furthermore, LINE-1 induction enabled by ODC1 interference provides a new experimental model to study mechanisms and consequences of LINE-1 activation in the etiology and progression of UC as well as presumably other cancers.


Assuntos
Epigênese Genética , Ornitina Descarboxilase/deficiência , Ornitina Descarboxilase/genética , Interferência de RNA , Neoplasias Urológicas/patologia , Urotélio/patologia , Apoptose/genética , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
19.
Genes Dev ; 34(7-8): 489-494, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32139422

RESUMO

Young mammals possess a limited regenerative capacity in some tissues, which is lost upon maturation. We investigated whether cellular senescence might play a role in such loss during liver regeneration. We found that following partial hepatectomy, the senescence-associated genes p21, p16Ink4a, and p19Arf become dynamically expressed in different cell types when regenerative capacity decreases, but without a full senescent response. However, we show that treatment with a senescence-inhibiting drug improves regeneration, by disrupting aberrantly prolonged p21 expression. This work suggests that senescence may initially develop from heterogeneous cellular responses, and that senotherapeutic drugs might be useful in promoting organ regeneration.


Assuntos
Compostos de Bifenilo/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/fisiologia , Nitrofenóis/farmacologia , Regeneração/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Piperazinas/farmacologia
20.
Clin Sci (Lond) ; 134(7): 889-905, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32219338

RESUMO

Senescence and mitochondrial stress are mutually reinforcing age-related processes that contribute to idiopathic pulmonary fibrosis (IPF); a lethal disease that manifests primarily in the elderly. Whilst evidence is accumulating that GMP-AMP synthase (cGAS) is crucial in perpetuating senescence by binding damaged DNA released into the cytosol, its role in IPF is not known. The present study examines the contributions of cGAS and self DNA to the senescence of lung fibroblasts from IPF patients (IPF-LFs) and age-matched controls (Ctrl-LFs). cGAS immunoreactivity was observed in regions of fibrosis associated with fibroblasts in lung tissue of IPF patients. Pharmacological inhibition of cGAS or its knockdown by silencing RNA (siRNA) diminished the escalation of IPF-LF senescence in culture over 7 days as measured by decreased p21 and p16 expression, histone 2AXγ phosphorylation and/or IL-6 production (P < 0.05, n = 5-8). The targeting of cGAS also attenuated etoposide-induced senescence in Ctrl-LFs (P < 0.05, n = 5-8). Levels of mitochondrial DNA (mDNA) detected by qPCR in the cytosol and medium of IPF-LFs or senescence-induced Ctrl-LFs were higher than Ctrl-LFs at baseline (P < 0.05, n = 5-7). The addition of DNAse I (100 U/ml) deaccelerated IPF-LF senescence (P < 0.05, n = 5), whereas ectopic mDNA or the induction of endogenous mDNA release augmented Ctrl-LF senescence in a cGAS-dependent manner (P < 0.05, n = 5). In conclusion, we provide evidence that cGAS reinforces lung fibroblast senescence involving damaged self DNA. The targeting of cGAS to supress senescent-like responses may have potential important therapeutic implications in the treatment of IPF.


Assuntos
Proliferação de Células , Senescência Celular , DNA Mitocondrial/metabolismo , Fibroblastos/enzimologia , Fibrose Pulmonar Idiopática/enzimologia , Pulmão/enzimologia , Nucleotidiltransferases/metabolismo , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Senescência Celular/efeitos dos fármacos , 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 , Dano ao DNA , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Histonas/metabolismo , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Interleucina-6/genética , Interleucina-6/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/genética , Comunicação Parácrina , Fosforilação , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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