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1.
Elife ; 122024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738857

RESUMO

Enhanced protein synthesis is a crucial molecular mechanism that allows cancer cells to survive, proliferate, metastasize, and develop resistance to anti-cancer treatments, and often arises as a consequence of increased signaling flux channeled to mRNA-bearing eukaryotic initiation factor 4F (eIF4F). However, the post-translational regulation of eIF4A1, an ATP-dependent RNA helicase and subunit of the eIF4F complex, is still poorly understood. Here, we demonstrate that IBTK, a substrate-binding adaptor of the Cullin 3-RING ubiquitin ligase (CRL3) complex, interacts with eIF4A1. The non-degradative ubiquitination of eIF4A1 catalyzed by the CRL3IBTK complex promotes cap-dependent translational initiation, nascent protein synthesis, oncogene expression, and cervical tumor cell growth both in vivo and in vitro. Moreover, we show that mTORC1 and S6K1, two key regulators of protein synthesis, directly phosphorylate IBTK to augment eIF4A1 ubiquitination and sustained oncogenic translation. This link between the CRL3IBTK complex and the mTORC1/S6K1 signaling pathway, which is frequently dysregulated in cancer, represents a promising target for anti-cancer therapies.


Assuntos
Fator de Iniciação 4A em Eucariotos , Alvo Mecanístico do Complexo 1 de Rapamicina , Biossíntese de Proteínas , Proteínas Quinases S6 Ribossômicas 70-kDa , Transdução de Sinais , Ubiquitinação , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/metabolismo , Fator de Iniciação 4A em Eucariotos/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética
2.
Environ Toxicol ; 39(5): 2794-2802, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38282581

RESUMO

Aerobic glycolysis is a typical metabolic rearrangement for tumorigenesis. Arecoline is of explicit carcinogenicity, numerous works demonstrate its mutagenicity, genotoxicity, and cytotoxicity. However, the effects of arecoline on aerobic glycolysis of esophageal epithelial cells remain unclear. In the present study, 5 µM arecoline efficiently increased HK2 expression to induce aerobic glycolysis in Het-1A-Are and NE2-Are cells. The mechanistic analysis showed that arecoline activated the Akt-c-Myc signaling pathway and reduced the GSK3ß-mediated phosphorylation of c-Myc on Thr58 to prevent its ubiquitination and destruction, subsequently promoting HK2 transcription and expression. Taken together, these results suggest that arecoline can induce aerobic glycolysis of esophageal epithelial cells and further confirm that arecoline is a carcinogen harmful to human health.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Humanos , Arecolina , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Glicólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
3.
Autophagy ; 20(2): 460-462, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37876279

RESUMO

Mitophagy, the process of removing damaged mitochondria to promote cell survival, plays a crucial role in cellular functionality. However, excessive, or uncontrolled mitophagy can lead to reduced mitochondrial content that burdens the remaining organelles, triggering mitophagy-mediated cell death. FBXL4 mutations, which affect the substrate-binding adaptor of the CUL1 (cullin 1)-RING ubiquitin ligase complex (CRL1), have been linked to mitochondrial DNA depletion syndrome type 13 (MTDPS13) characterized by reduced mtDNA content and impaired energy production in affected organs. However, the mechanism behind FBXL4 mutation-driven MTDPS13 remain poorly understood. In a recent study, we demonstrate that the CRL1-FBXL4 complex promotes the degradation of BNIP3 and BNIP3L, two key mitophagy cargo receptors. Deficiency of FBXL4 results in a strong accumulation of BNIP3 and BNIP3L proteins and triggers high levels of BNIP3- and BNIP3L-dependent mitophagy. Patient-derived FBXL4 mutations do not affect its interaction with BNIP3 and BNIP3L but impair the assembly of an active CRL1-FBXL4 complex. Furthermore, excessive mitophagy is observed in knockin mice carrying a patient-derived FBXL4 mutation, and in cortical neurons generated from human patient induced pluripotent stem cells (hiPSCs). These findings support the model that the CRL1-FBXL4 complex tightly restricts basal mitophagy, and its dysregulation leads to severe symptoms of MTDPS13.


Assuntos
Autofagia , Doenças Mitocondriais , Mitofagia , Animais , Humanos , Camundongos , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/genética , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitofagia/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas F-Box/genética , Ubiquitina-Proteína Ligases/genética , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo
4.
PLoS One ; 18(10): e0293432, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37903087

RESUMO

BACKGROUND: COVID-19 and influenza A can cause severe respiratory illness. Differentiating between the two diseases and identifying critically ill patients in times of epidemics become a challenge for frontline medical staff. We sought to investigate whether both diseases and their severity could be recognized by routine blood parameters. METHODS: Our retrospective study analysed the clinical data and first-time routine blood parameters of 80 influenza A patients and 123 COVID-19 patients. COVID-19 patients were divided into three groups according to treatment modalities and outcomes: outpatient group, inpatient without invasive mechanical ventilation (IMV) group, and inpatient with IMV group. We used the Mann-Whitney and Kruskal-Wallis tests to analyze the differences in routine blood parameters between the two or three groups. Receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) were used to assess the diagnostic accuracy. RESULTS: Compared with outpatient influenza A patients, outpatient COVID-19 patients had a higher neutrophil to lymphocyte ratio (NLR) (6.63 vs 3.55). ROC analysis showed that the NLR had a high diagnostic value for differentiating COVID-19 from influenza A (AUC = 0.739). The best cut-off point of the NLR was 6.48, the diagnostic sensitivity was 0.523, and the specificity was 0.925. The median platelet (PLT) count in the different COVID-19 groups was as follows: outpatient group (189×109/L), inpatient without IMV group (161×109/L), and inpatient with IMV group (94×109/L). Multivariate logistic regression analysis found a significant association between PLT and treatment modality and outcome in COVID-19 patients (p<0.001). CONCLUSIONS: NLR can be used as a potential biological indicator to distinguish COVID-19 and influenza A. Decreased PLT predicts the critical condition of COVID-19 patients and helps stratify the treatment of COVID-19 patients.


Assuntos
COVID-19 , Influenza Humana , Humanos , Neutrófilos , COVID-19/diagnóstico , Estudos Retrospectivos , Influenza Humana/diagnóstico , Linfócitos , Curva ROC , Prognóstico , Teste para COVID-19
5.
World J Urol ; 41(12): 3753-3758, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37838641

RESUMO

OBJECTIVE: To investigate the association between low-dose aspirin use for primary prevention and self-reported kidney stones prevalence in the 40-79 years old population. METHODS: We conducted a cross-sectional study based on the United States population data from the National Health and Nutrition Examination Survey 2011-2018. Baseline demographical and clinical data were collected. The univariate and multivariate regression was performed to identify confounding factors and assess the relationship between aspirin use for primary prevention and the prevalence of self-reported kidney stones. A propensity-score matching was used to identify patients with similar baseline characteristics to adjust for the bias caused by confounding factors. RESULTS: A total of 10,256 low-dose aspirin-use participants were included in this study. 10.4% of participants reported a history of kidney stones, and 18.5% reported a continuous use of low-dose prophylactic aspirin. Multivariate logistic regression analysis showed that low-dose preventive aspirin use had significantly increased the odds of self-reported kidney stones (OR = 1.245; 95% CI: 1.063-1.459; p = 0.007). In subgroup analysis, this finding was primarily limited to males (OR = 1.311), non-hypertensive participants (OR = 1.443), diabetic participants (OR = 1.380), and older (60 ≤ Age < 80) (OR = 1.349). The propensity-score matched analyses supported this result after adjusting for the bias caused by potential confounders (OR = 1.216; 95% CI: 1.011-1.462; p = 0.038). CONCLUSION: In this study, there exists a significant relationship between low-dose aspirin for primary prevention and self-reported kidney stones, primarily among males, no hypertensive participants, diabetics, or older adults. Further studies are needed to elucidate the mechanisms underlying these findings in the future.


Assuntos
Diabetes Mellitus , Hipertensão , Cálculos Renais , Masculino , Humanos , Estados Unidos/epidemiologia , Idoso , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Autorrelato , Inquéritos Nutricionais , Aspirina/uso terapêutico , Cálculos Renais/epidemiologia , Cálculos Renais/prevenção & controle , Cálculos Renais/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Hipertensão/tratamento farmacológico , Prevenção Primária
6.
Sci Rep ; 13(1): 18226, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880277

RESUMO

Lung adenocarcinoma (LUAD) remains an incurable disease with a poor prognosis. This study aimed to explore neutrophil­related genes (NRGs) and develop a prognostic signature for predicting the prognosis of LUAD. NRGs were obtained by intersecting modular genes identified by weighted gene co-expression network analysis (WGCNA) using bulk RNA-seq data and the marker genes of neutrophils identified from single-cell RNA-sequencing(scRNA-seq) data. Univariate Cox regression, least absolute shrinkage and selection operator (LASSO), and multivariate Cox analyses were run to construct a prognostic signature, follow by delineation of risk groups, and external validation. Analyses of ESTIMAT, immune function, Tumor Immune Dysfunction and Exclusion (TIDE) scores, Immune cell Proportion Score (IPS), and immune checkpoint genes between high- and low-risk groups were performed, and then analyses of drug sensitivity to screen for sensitive anticancer drugs in high-risk groups. A total of 45 candidate NRGs were identified, of which PLTP, EREG, CD68, CD69, PLAUR, and CYP27A1 were considered to be significantly associated with prognosis in LUAD and were used to construct a prognostic signature. Correlation analysis showed significant differences in the immune landscape between high- and low-risk groups. In addition, our prognostic signature was important for predicting drug sensitivity in the high-risk group. Our study screened for NRGs in LUAD and constructed a novel and effective signature, revealing the immune landscape and providing more appropriate guidance protocols in LUAD treatment.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Neutrófilos , Adenocarcinoma de Pulmão/genética , Perfilação da Expressão Gênica , Neoplasias Pulmonares/genética
7.
Noncoding RNA Res ; 8(4): 641-644, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37810370

RESUMO

miRNA is a noncoding RNA found in recent years and more than one third of human genes are the target of miRNAs. miR-624, located on human chromosome 14, is associated with tumorigenesis. However, the role of miR-624 in human hepatocarcinogenesis is still unclear. Herein, our results indicate that miR-624 accelerates the growth of liver cancer cells in vivo and in vitro. Moreover, the modification distribution of H3K9me1 on chromosomes is different between rLV group and rLV-miR-624 group. miR-624 affects epigenetic regulation of several genes in human liver cancer cells, such as RAB21, SMARCD3, MAPK6,PRRX1, ZFHX3, EMC3 (TMEM111). Furthermore, miR-624 affects transcriptome of some genes in liver cancer, including RAB21, UBE2N, PPP1CC,KPNA3, RAB7A,CPEB2,KLF4, MARK2, JUN, ARF6, TMEM39A. On the other hand, miR-624 affects proteome of several genes in liver cancer, such as, RBM5,PTK2, KDM2A,POLR2H, POLR2G,CDK6,KIF15,CUL2,FKBP2,ErbB-3,JUN, PKM2, CyclinE,PLK1, mTOR, PPARγ, Rab7A,ARAF, UPF3B ,PTEN, SUZ12, GADD45, H3.3, CUL5, ARF6,EMC3,ATG4B,ATG14,CALR. Interestingly, miR-624 affects the RAB7A interaction network in liver cancer cells, involving in CLTC,ITGB1,HNRNPU, DARS1, RPS16, CTPS1,H3-3B,JUN,MYH10, CUL5, CPSF7. Strikingly, excessive MEC3 abrogates the carcinogenic functions of miR-624. Importantly, our findings indicate that miR-624 affects some signaling pathway in liver cancer, including Wnt signaling pathway,Hippo signaling pathway,mTOR signaling pathway, Ras signaling pathway,MAPK signaling pathway,PI3K-Akt signaling pathway, erbB signaling pathway. These results provide a basis for the treatment of human liver cancer.

8.
Redox Biol ; 67: 102872, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37688978

RESUMO

The mechanistic target of the rapamycin (mTOR) pathway, which participates in the regulation of cellular growth and metabolism, is aberrantly regulated in various cancer types. The mTOR complex 2 (mTORC2), which consists of the core components mTOR, Rictor, mSin1, and mLST8, primarily responds to growth signals. However, the coordination between mTORC2 assembly and activity remains poorly understood. Keap1, a major sensor of oxidative stress in cells, functions as a substrate adaptor for Cullin 3-RING E3 ubiquitin ligase (CRL3) to promote proteasomal degradation of NF-E2-related factor 2 (NRF2), which is a transcription factor that protects cells against oxidative and electrophilic stress. In the present study, we demonstrate that Keap1 binds to mLST8 via a conserved ETGE motif. The CRL3Keap1 ubiquitin ligase complex promotes non-degradative ubiquitination of mLST8, thus reducing mTORC2 complex integrity and mTORC2-AKT activation. However, this effect can be prevented by oxidative/electrophilic stresses and growth factor signaling-induced reactive oxygen species (ROS) burst. Cancer-derived Keap1 or mLST8 mutations disrupt the Keap1-mLST8 interaction and allow mLST8 to evade Keap1-mediated ubiquitination, thereby enhancing mTORC2-AKT activation and promoting cell malignancy and remodeling cell metabolism. Our findings provide new insights into the molecular mechanisms of Keap1/mLST8 mutation-driven tumorigenesis by promoting mTORC2-AKT activation, which is independent of the canonical NRF2 pathway.


Assuntos
Neoplasias , Proteínas Proto-Oncogênicas c-akt , Humanos , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias/genética , Mutação
9.
Cancer Res ; 83(23): 3940-3955, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37713596

RESUMO

The KEAP1-NRF2 axis is the principal regulator of cellular responses to oxidative and electrophilic stressors. NRF2 hyperactivation is frequently observed in many types of cancer and promotes cancer initiation, progression, metastasis, and resistance to various therapies. Here, we determined that dipeptidyl peptidase 9 (DPP9) is a regulator of the KEAP1-NRF2 pathway in clear cell renal cell carcinoma (ccRCC). DPP9 was markedly overexpressed at the mRNA and protein levels in ccRCC, and high DPP9 expression levels correlated with advanced tumor stage and poor prognosis in patients with ccRCC. Protein affinity purification to identify functional partners of DPP9 revealed that it bound to KEAP1 via a conserved ESGE motif. DPP9 disrupted KEAP1-NRF2 binding by competing with NRF2 for binding to KEAP1 in an enzyme-independent manner. Upregulation of DPP9 led to stabilization of NRF2, driving NRF2-dependent transcription and thereby decreasing cellular reactive oxygen species levels. Moreover, DPP9 overexpression suppressed ferroptosis and induced resistance to sorafenib in ccRCC cells, which was largely dependent on the NRF2 transcriptional target SLC7A11. Collectively, these findings indicate that the accumulation of DPP9 results in hyperactivation of the NRF2 pathway to promote tumorigenesis and intrinsic drug resistance in ccRCC. SIGNIFICANCE: DPP9 overcomes oxidative stress and suppresses ferroptosis in ccRCC by binding to KEAP1 and promoting NRF2 stability, which drives tumor development and sorafenib resistance.


Assuntos
Carcinoma de Células Renais , Ferroptose , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/genética , Sorafenibe/farmacologia
10.
Cell Death Differ ; 30(10): 2351-2363, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37568009

RESUMO

Mitochondria are essential organelles found in eukaryotic cells that play a crucial role in ATP production through oxidative phosphorylation (OXPHOS). Mitochondrial DNA depletion syndrome (MTDPS) is a group of genetic disorders characterized by the reduction of mtDNA copy number, leading to deficiencies in OXPHOS and mitochondrial functions. Mutations in FBXL4, a substrate-binding adaptor of Cullin 1-RING ubiquitin ligase complex (CRL1), are associated with MTDPS, type 13 (MTDPS13). Here, we demonstrate that, FBXL4 directly interacts with the mitophagy cargo receptors BNIP3 and BNIP3L, promoting their degradation through the ubiquitin-proteasome pathway via the assembly of an active CRL1FBXL4 complex. However, MTDPS13-associated FBXL4 mutations impair the assembly of an active CRL1FBXL4 complex. This results in a notable accumulation of BNIP3/3L proteins and robust mitophagy even at basal levels. Excessive mitophagy was observed in Knockin (KI) mice carrying a patient-derived FBXL4 mutation and cortical neurons (CNs)-induced from MTDPS13 patient human induced pluripotent stem cells (hiPSCs). In summary, our findings suggest that abnormal activation of BNIP3/BNIP3L-dependent mitophagy impairs mitochondrial homeostasis and underlies FBXL4-mutated MTDPS13.

11.
Cancer Sci ; 114(9): 3568-3582, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37311571

RESUMO

BACH1 plays an important role in promoting cancer. This study aims to further verify the relationship between the expression level of BACH1 in lung adenocarcinoma prognosis, as well as the influence of BACH1 expression on lung adenocarcinoma and the potential mechanism. The expression level of BACH1 in lung adenocarcinoma and its relationship with prognosis was evaluated by lung adenocarcinoma tissue microarray analysis combined with bioinformatics approaches. Gene knockdown and overexpression were used to investigate the functions and molecular mechanisms of BACH1 in lung adenocarcinoma cells. The regulatory downstream pathways and target genes of BACH1 in lung adenocarcinoma cells were explored by bioinformatics and RNA sequencing data analysis, real-time PCR, western blot analysis, and cell immunofluorescence and cell adhesion assays. Chromatin immunoprecipitation and dual-luciferase reporter assays were carried out to verify the target gene binding site. In the present study, BACH1 is abnormally highly expressed in lung adenocarcinoma tissues, and high BACH1 expression is negatively correlated with patient prognosis. BACH1 promotes the migration and invasion of lung adenocarcinoma cells. Mechanistically, BACH1 directly binds to the upstream sequence of the ITGA2 promoter to promote ITGA2 expression, and the BACH1-ITGA2 axis is involved in cytoskeletal regulation in lung adenocarcinoma cells by activating the FAK-RAC1-PAK signaling pathway. Our results indicated that BACH1 positively regulates the expression of ITGA2 through a transcriptional mechanism, thereby activating the FAK-RAC1-PAK signaling pathway to participate in the formation of the cytoskeleton in tumor cells and then promoting the migration and invasion of tumor cells.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Adenocarcinoma/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Transdução de Sinais/genética , Ativação Transcricional
12.
Front Oncol ; 13: 1322078, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38293701

RESUMO

Deregulation of cell cycles can result in a variety of cancers, including breast cancer (BC). In fact, abnormal regulation of cell cycle pathways is often observed in breast cancer, leading to malignant cell proliferation. CDK4/6 inhibitors (CDK4/6i) can block the G1 cell cycle through the cyclin D-cyclin dependent kinase 4/6-inhibitor of CDK4-retinoblastoma (cyclinD-CDK4/6-INK4-RB) pathway, thus blocking the proliferation of invasive cells, showing great therapeutic potential to inhibit the spread of BC. So far, three FDA-approved drugs have been shown to be effective in the management of advanced hormone receptor positive (HR+) BC: palbociclib, abemaciclib, and ribociclib. The combination strategy of CDK4/6i and endocrine therapy (ET) has become the standard therapeutic regimen and is increasingly applied to advanced BC patients. The present study aims to clarify whether CDK4/6i can also achieve a certain therapeutic effect on Human epidermal growth factor receptor 2 positive (HER2+) BC. Studies of CDK4/6i are not limited to patients with estrogen receptor positive/human epidermal growth factor receptor 2 negative (ER+/HER2-) advanced BC, but have also expanded to other types of BC. Several pre-clinical and clinical trials have demonstrated the potential of CDK4/6i in treating HER2+ BC. Therefore, this review summarizes the current knowledge and recent findings on the use of CDK4/6i in this type of BC, and provides ideas for the discovery of new treatment modalities.

13.
Cell Biosci ; 12(1): 211, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585710

RESUMO

BACKGROUND: The gene encoding the E3 ubiquitin ligase substrate-binding adapter Speckle-type BTB/POZ protein (SPOP) is frequently mutated in prostate cancer (PCa) and endometrial cancer (EC); however, the molecular mechanisms underlying the contribution of SPOP mutations to tumorigenesis remain poorly understood. METHODS: BRAF harbors a potential SPOP-binding consensus motif (SBC) motif. Co-immunoprecipitation assays demonstrated that BRAF interacts with SPOP. A series of functional analyses in cell lines were performed to investigate the biological significance of MAPK/ERK activation caused by SPOP mutations. RESULTS: Cytoplasmic SPOP binds to and induces non-degradative ubiquitination of BRAF, thereby reducing the interaction between BRAF and other core components of the MAPK/ERK pathway. SPOP ablation increased MAPK/ERK activation. EC- or PCa-associated SPOP mutants showed a reduced capacity to bind and ubiquitinate BRAF. Moreover, cancer-associated BRAF mutations disrupted the BRAF-SPOP interaction and allowed BRAF to evade SPOP-mediated ubiquitination, thereby upregulating MAPK/ERK signaling and enhancing the neoplastic phenotypes of cancer cells. CONCLUSIONS: Our findings provide new insights into the molecular link between SPOP mutation-driven tumorigenesis and aberrant BRAF-dependent activation of the MAPK/ERK pathway.

14.
Oncogene ; 41(21): 3000-3010, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35459779

RESUMO

Members of the Inhibitor of Apoptosis Protein (IAP) family are essential for cell survival and appear to neutralize the cell death machinery by binding pro-apoptotic caspases. dcaf12 was recently identified as an apoptosis regulator in Drosophila. However, the underlying molecular mechanisms are unknown. Here we revealed that human DCAF12 homolog binds multiple IAPs, including XIAP, cIAP1, cIAP2, and BRUCE, through recognition of BIR domains in IAPs. The pro-apoptotic function of DCAF12 is dependent on its capacity to bind IAPs. In response to apoptotic stimuli, DCAF12 translocates from the nucleus to the cytoplasm, where it blocks the interaction between XIAP and pro-apoptotic caspases to facilitate caspase activation and apoptosis execution. Similarly, DCAF12 suppresses NF-κB activation in an IAP binding-dependent manner. Moreover, DCAF12 acts as a tumor suppressor to restrict the malignant phenotypes of cancer cells. Together, our results suggest that DCAF12 is an evolutionarily conserved IAP antagonist.


Assuntos
Proteínas Inibidoras de Apoptose , NF-kappa B , Apoptose , Caspases/metabolismo , Sobrevivência Celular , Humanos , Proteínas Inibidoras de Apoptose/química , Proteínas Inibidoras de Apoptose/genética , NF-kappa B/metabolismo , Domínios Proteicos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
15.
Cancer Cell Int ; 22(1): 19, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35016691

RESUMO

BACKGROUND: The roles of Polypyrimidine tract-binding protein 3 (PTBP3) in regulating lung squamous cell carcinoma (LUSC) cells progression is unclear. The aim of this study was to investigate the role of PTBP3 in LUSC. METHODS: Expression and survival analysis of PTBP3 was firstly investigated using TCGA datasets. Quantitative reverse transcription PCR and Western blot were performed to detect PTBP3 expression in clinical samples. Moreover, cell counting kit 8 (CCK-8) assays, colony formation assays and in vivo tumor formation assays were used to examine the effects of PTBP3 on LUSC cell proliferation. RNA-sequence and analysis explores pathways regulated by PTBP3.Flow cytology was used analyzed cell cycle. Cell cycle-related markers were analyzed by Western blot. RESULTS: PTBP3 was found to be overexpressed in LUSC tissues compared with normal tissues. High PTBP3 expression was significantly correlated with poor prognosis. In vitro and vivo experiments demonstrated that PTBP3 knockdown caused a significant decrease in the proliferation rate of cells. Bioinformatics analysis showed that PTBP3 involved in cell cycle pathway regulation in LUSC. Furthermore, PTBP3 knockdown arrested cell cycle progression at S phase via decreasing CDK2/Cyclin A2 complex. In addition, downregulation of PTBP3 significantly decreased the expression of CDC25A. CONCLUSIONS: Our results suggest that PTBP3 regulated LUSC cell proliferation via cell cycle and might be a potential target for molecular therapy of LUSC.

16.
Cell Death Differ ; 29(4): 758-771, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34743205

RESUMO

The cystine/glutamate antiporter SLC7A11 (commonly known as xCT) functions to import cystine for glutathione biosynthesis, thereby protecting cells from oxidative stress and ferroptosis, a regulated form of non-apoptotic cell death driven by the accumulation of lipid-based reactive oxygen species (ROS). p14ARF, a well-established tumor suppressor, promotes ferroptosis by inhibiting NRF2-mediated SLC7A11 transcription. Here, we demonstrate the crucial role of Cullin 2 RING E3 ligase (CRL2)-KLHDC3 E3 ubiquitin ligase complex in regulating p14ARF protein stability. KLHDC3 acts as a CRL2 adaptor that specifically recognizes a C-terminal degron in p14ARF and triggers p14ARF for ubiquitin-proteasomal degradation. This regulation mode is absent in the murine p14ARF homolog, p19arf which lacks the C-terminal degron. We also show that KLHDC3 suppresses ferroptosis in vitro and supports tumor growth in vivo by relieving p14ARF-mediated suppression of SLC7A11 transcription. Overall, these findings reveal that the protein stability and pro-ferroptotic function of p14ARF are controlled by a CRL2 E3 ubiquitin ligase complex, and suggest that suppression of the p14ARF-NRF2-SLC7A11 regulatory pathway by KLHDC3 overexpression likely contributes to cancer progression.


Assuntos
Proteínas de Ciclo Celular , Ferroptose , Proteína Supressora de Tumor p14ARF , Ubiquitina-Proteína Ligases , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cistina , Camundongos , Proteína Supressora de Tumor p14ARF/metabolismo , Ubiquitina-Proteína Ligases/genética
17.
Cell Death Dis ; 12(7): 634, 2021 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-34148062

RESUMO

Signal transducer and activator 5a (STAT5A) is a classical transcription factor that plays pivotal roles in various biological processes, including tumor initiation and progression. A fraction of STAT5A is localized in the mitochondria, but the biological functions of mitochondrial STAT5A remain obscure. Here, we show that STAT5A interacts with pyruvate dehydrogenase complex (PDC), a mitochondrial gatekeeper enzyme connecting two key metabolic pathways, glycolysis and the tricarboxylic acid cycle. Mitochondrial STAT5A disrupts PDC integrity, thereby inhibiting PDC activity and remodeling cellular glycolysis and oxidative phosphorylation. Mitochondrial translocation of STAT5A is increased under hypoxic conditions. This strengthens the Warburg effect in cancer cells and promotes in vitro cell growth under hypoxia and in vivo tumor growth. Our findings indicate distinct pro-oncogenic roles of STAT5A in energy metabolism, which is different from its classical function as a transcription factor.


Assuntos
Mitocôndrias/enzimologia , Complexo Piruvato Desidrogenase/metabolismo , Fator de Transcrição STAT5/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias do Colo do Útero/enzimologia , Efeito Warburg em Oncologia , Trifosfato de Adenosina/metabolismo , Animais , Proliferação de Células , Feminino , Glicólise , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/genética , Mitocôndrias/patologia , Fosforilação Oxidativa , Consumo de Oxigênio , Fator de Transcrição STAT5/genética , Carga Tumoral , Hipóxia Tumoral , Microambiente Tumoral , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
18.
Front Oncol ; 11: 644426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33937050

RESUMO

BACKGROUND: Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer. At present, most patients with LUAD are diagnosed at an advanced stage, and the prognosis of advanced LUAD is poor. Hence, we aimed to identify novel biomarkers for the diagnosis and treatment of early stage LUAD and to explore their predictive value. METHODS: The microarray datasets GSE63459, GSE27262, and GSE33532 were searched, and the differentially expressed genes (DEGs) were obtained using GEO2R. The DEGs were subjected to gene ontology (GO) and pathway enrichment analyses using METASCAPE. A protein-protein interaction (PPI) network was plotted with STRING and visualized by Cytoscape. Module analysis of the PPI network was performed using MCODE. Overall survival (OS) analysis and analysis of the mRNA expression levels of genes identified by MCODE were performed with UALCAN. Western blot analysis of hub genes in LUAD patients, MTS assays, and clonogenic assays were performed to test the effects of the hub genes on cell proliferation in vitro. RESULTS: A total of 341 DEGs were obtained, which were mainly enriched in terms related to blood vessel development, growth factor binding, and extracellular matrix organization. A PPI network consisting of 300 nodes and 1140 edges was constructed, and a significant module including 15 genes was identified. Elevated expression of ASPM, CCNB2, CDCA5, PRC1, KIAA0101, and UBE2T was associated with poor OS in LUAD patients. In the protein level, the hub gene was overexpressed in LUAD patients. In vitro experiments showed that knockdown of the hub genes in the LUAD cell lines could promote cell proliferation. CONCLUSIONS: DEGs are potential biomarkers for early stage lung adenocarcinoma and could have utility for the diagnosis and predicting treatment efficacy.

19.
World J Surg Oncol ; 18(1): 188, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32723382

RESUMO

BACKGROUND: Lateral lymph node metastasis (LLNM) is very common in papillary thyroid carcinoma (PTC). The influence of tumour location on LLNM remains controversial. The purpose of this study was to reveal the association between PTC tumours located in the upper pole and LLNM. METHODS: We reviewed a total of 1773 PTC patients who underwent total thyroidectomy with central and lateral lymph node dissection between 2013 and 2018. Patients were divided into two groups according to tumour location. Univariate and multivariate analyses were performed to identify risk factors associated with LLNM and "skip metastasis". RESULTS: In the upper pole group, LLNM and skip metastasis were significantly likely to occur. Multivariate analysis showed that tumours located in the upper pole, male sex, extrathyroidal extension (ETE), central lymph node metastasis (CLNM) and tumour size were independent risk factors for LLNM, with odds ratios ([ORs], 95% confidence intervals [CIs]) of 2.136 (1.707-2.672), 1.486 (1.184-1.867), 1.332 (1.031-1.72), 4.172 (3.279-5.308) and 2.496 (1.844-3.380), respectively. Skip metastasis was significantly associated with the primary tumour location in the upper pole and age > 55 years, with ORs of 4.295 (2.885-6.395) and 2.354 (1.522-3.640), respectively. CONCLUSIONS: In our opinion, papillary thyroid tumours located in the upper pole may have an exclusive drainage pathway to the lateral lymph nodes. When the tumour is located in the upper pole, lateral neck dissection should be evaluated meticulously.


Assuntos
Linfonodos , Neoplasias da Glândula Tireoide , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
20.
Gland Surg ; 9(2): 172-182, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32420240

RESUMO

BACKGROUND: The purpose of this study was to evaluate the factors associated with lateral lymph node metastasis (LLNM) in patients with papillary thyroid carcinoma (PTC), and to develop two web-based nomograms that predict the probability of level-II and level-III/IV LLNM in these patients. METHODS: The records of 653 patients with PTC were retrospectively reviewed. Univariate and multivariate analyses were performed to identify risk factors associated with LLNM in 460 patients ("derivation group"). Two models [including and excluding the subregions of central lymph node metastasis (CLNM)] were used to predict the probability of level-II LLNM; the same two models were also used for level-III/IV LLNM. Model performance was assessed using receiver operating characteristic (ROC) analysis and decision curve analysis (DCA) in 193 patients ("validation group"). Two web-based nomograms were established. RESULTS: Increased tumor size, a tumor in the upper lobe, and prelaryngeal and ipsilateral paratracheal lymph node metastasis (LNM) were significantly associated with level-II LNM (P<0.05). Increased tumor size, a tumor in the upper lobe, and certain subregions of CLNM were associated with level-III/IV LNM (P<0.05). Use of ROC analysis of each model indicated that including subgroups of CLNM led to better model performance than excluding these subgroups. We quantified the benefit of each model by using DCA analysis in the validation group. CONCLUSIONS: Our web-based nomograms provide quantification of risk for LLNM in patients with PTC before and during surgery.

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