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1.
Proc Natl Acad Sci U S A ; 121(28): e2320655121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38959043

RESUMO

SLC7A11 is a cystine transporter and ferroptosis inhibitor. How the stability of SLC7A11 is coordinately regulated in response to environmental cystine by which E3 ligase and deubiquitylase (DUB) remains elusive. Here, we report that neddylation inhibitor MLN4924 increases cystine uptake by causing SLC7A11 accumulation, via inactivating Cullin-RING ligase-3 (CRL-3). We identified KCTD10 as the substrate-recognizing subunit of CRL-3 for SLC7A11 ubiquitylation, and USP18 as SLC7A11 deubiquitylase. Upon cystine deprivation, the protein levels of KCTD10 or USP18 are decreased or increased, respectively, contributing to SLC7A11 accumulation. By destabilizing or stabilizing SLC7A11, KCTD10, or USP18 inversely regulates the cystine uptake and ferroptosis. Biologically, MLN4924 combination with SLC7A11 inhibitor Imidazole Ketone Erastin (IKE) enhanced suppression of tumor growth. In human breast tumor tissues, SLC7A11 levels were negatively or positively correlated with KCTD10 or USP18, respectively. Collectively, our study defines how SLC7A11 and ferroptosis is coordinately regulated by the CRL3KCTD10/E3-USP18/DUB axis, and provides a sound rationale of drug combination to enhance anticancer efficacy.


Assuntos
Sistema y+ de Transporte de Aminoácidos , Cistina , Ferroptose , Pirimidinas , Ubiquitina Tiolesterase , Humanos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Pirimidinas/farmacologia , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Animais , Cistina/metabolismo , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Linhagem Celular Tumoral , Ubiquitinação , Feminino , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Piperazinas/farmacologia , Células HEK293
2.
Mol Cancer ; 19(1): 129, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32838807

RESUMO

BACKGROUND: Heat shock transcription factor1 (HSF1) was overexpressed to promote glutaminolysis and activate mTOR in colorectal cancer (CRC). Here, we investigated the mechanism for cancer-specific overexpression of HSF1. METHODS: HSF1 expression was analyzed by chromatin immunoprecipitation, qRT-PCR, immunohistochemistry staining and immunoblotting. HSF1 translation was explored by polysome profiling and nascent protein analysis. Biotin pulldown and m6A RNA immunoprecipitation were applied to investigate RNA/RNA interaction and m6A modification. The relevance of HSF1 to CRC was analyzed in APCmin/+ and APCmin/+ HSF1+/-mice. RESULTS: HSF1 expression and activity were reduced after the inhibition of WNT/ß-catenin signaling by pyrvinium or ß-catenin knockdown, but elevated upon its activation by lithium chloride (LiCl) or ß-catenin overexpression. There are much less upregulated genes in HSF1-KO MEF treated with LiCl when compared with LiCl-treated WT MEF. HSF1 protein expression was positively correlated with ß-catenin expression in cell lines and primary tissues. After ß-catenin depletion, HSF1 mRNA translation was impaired, accompanied by the reduction of its m6A modification and the upregulation of miR455-3p, which can interact with 3'-UTR of HSF1 mRNA to repress its translation. Interestingly, inhibition of miR455-3p rescued ß-catenin depletion-induced reduction of HSF1 m6A modification and METTL3 interaction. Both the size and number of tumors were significantly reduced in APCmin/+ mice when HSF1 was genetically knocked-out or chemically inhibited. CONCLUSIONS: ß-catenin suppresses miR455-3p generation to stimulate m6A modification and subsequent translation of HSF1 mRNA. HSF1 is important for ß-catenin to promote CRC development. Targeting HSF1 could be a potential strategy for the intervention of ß-catenin-driven cancers.


Assuntos
Adenosina/análogos & derivados , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição de Choque Térmico/genética , MicroRNAs/genética , RNA Mensageiro/genética , beta Catenina/metabolismo , Adenosina/metabolismo , Animais , Apoptose/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Modelos Animais de Doenças , Humanos , Metilação , Camundongos , Modelos Biológicos , Biossíntese de Proteínas , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Med Genet ; 51(3): 176-84, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24367055

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a primary disorder characterised by asymmetric thickening of septum and left ventricular wall, with a prevalence of 0.2% in the general population. OBJECTIVE: To describe a novel mitochondrial DNA mutation and its association with the pathogenesis of HCM. METHODS AND RESULTS: All maternal members of a Chinese family with maternally transmitted HCM exhibited variable severity and age at onset, and were implanted permanent pacemakers due to complete atrioventricular block (AVB). Nuclear gene screening (MYH7, MYBPC3, TNNT2 and TNNI3) was performed, and no potential pathogenic mutation was identified. Mitochondrial DNA sequencing analysis identified a novel homoplasmic 16S rRNA 2336T>C mutation. This mutation was exclusively present in maternal members and absent in non-maternal members. Conservation index by comparison to 16 other vertebrates was 94.1%. This mutation disturbs the 2336U-A2438 base pair in the stem-loop structure of 16S rRNA domain III, which is involved in the assembly of mitochondrial ribosome. Oxygen consumption rate of the lymphoblastoid cells carrying 2336T>C mutation had decreased by 37% compared with controls. A reduction in mitochondrial ATP synthesis and an increase in reactive oxidative species production were also observed. Electron microscopic analysis indicated elongated mitochondria and abnormal mitochondrial cristae shape in mutant cells. CONCLUSIONS: It is suggested that the 2336T>C mutation is one of pathogenic mutations of HCM. This is the first report of mitochondrial 16S rRNA 2336T>C mutation and an association with maternally inherited HCM combined with AVB. Our findings provide a new insight into the pathogenesis of HCM.


Assuntos
Cardiomiopatia Hipertrófica/genética , Proteínas Mitocondriais/genética , Mutação/genética , RNA Ribossômico 16S/genética , Adolescente , Adulto , Povo Asiático/genética , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo
4.
Prenat Diagn ; 34(11): 1061-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24899146

RESUMO

OBJECTIVE: The aim of this study is to report the clinical application of noninvasive prenatal testing (NIPT) to detect chromosomal aneuploidies, especially trisomies 21, 18, and 13 in Chinese singleton pregnancies. METHODS: Pilot validation between NIPT with full karyotyping was conducted blindly on 306 cases. Subsequently, 7705 pregnancies were offered with NIPT. Follow-up data was obtained in all cases. RESULTS: In the validation stage, a total of five NIPT positive cases were observed for trisomies 21 and 18, and results were confirmed by karyotyping; there were no cases of trisomy 13. Thus, the overall sensitivity and specificity in the validation stage was 100%. In 7705 cases, NIPT results were obtained in 7701 cases; 66 cases were classified as positive, including 48 cases of trisomy 21, 14 cases of trisomy 18, and 4 cases of trisomy 13. Subsequent karyotyping documented two false positive diagnoses for trisomies 21, 18, and 13, respectively. Sensitivity and specificity for detection of trisomies 21 and 18 and 13 were 100% and 99.9%, respectively. Additionally, prenatal chromosomal detection for pregnancies with NIPT has shown a gradual increase since its implementation. CONCLUSION: Noninvasive prenatal testing allows a more suitable and efficient workflow for our patients' needs, together with invasive procedures allows a higher prenatal detection of chromosomal aneuploidies.


Assuntos
Transtornos Cromossômicos/diagnóstico , Síndrome de Down/diagnóstico , Diagnóstico Pré-Natal/métodos , Trissomia/diagnóstico , Adulto , Aneuploidia , Transtornos Cromossômicos/epidemiologia , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 18 , Síndrome de Down/epidemiologia , Reações Falso-Positivas , Feminino , Humanos , Recém-Nascido , Cariotipagem , Idade Materna , Gravidez , Diagnóstico Pré-Natal/estatística & dados numéricos , Estudos Retrospectivos , Síndrome da Trissomia do Cromossomo 13 , Síndrome da Trissomía do Cromossomo 18
5.
Medicine (Baltimore) ; 103(23): e38526, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847685

RESUMO

Tubal pregnancy is a common cause of maternal mortality in early pregnancy. Transumbilical laparoendoscopic single-site surgery (TU-LESS) has gained popularity due to its safety and aesthetic advantages. However, the lack of affordable disposable entry platforms hinders its widespread adoption. This study aimed to investigate the learning curve of tubal pregnancy removal using single-incision multiport (SIMP) laparoscopy and provide guidance for novice gynecologists. A retrospective analysis was conducted on cases of ectopic pregnancy (EP) diagnosed at Dongguan Songshan Lake Central Hospital from June 2020 to June 2022. The analysis included 50 cases, with 25 undergoing single-port laparoscopy and 25 undergoing conventional laparoscopy (CL). Various indicators, including body mass index (BMI), previous pregnancies, mass size, hemoglobin levels, surgical duration, and complications, were collected. Learning curve analysis using the cumulative sum (CUSUM) technique was performed to assess procedural proficiency. There were no significant differences in patient characteristics or complications between the 2 groups. However, the single-port laparoscopy group exhibited a statistically significant longer average surgical time (41.60 ±â€…13.38 minutes) compared to the conventional laparotomy group (32.96 ±â€…7.32 minutes). The CUSUM analysis demonstrated a decline in surgical time after the completion of approximately 11 cases, indicating an improvement in SIMP laparoscopy surgical proficiency. SIMP laparoscopy for tubal pregnancy removal achieved similar safety outcomes as CL. Notably, the CUSUM analysis revealed that proficiency in single-port laparoscopy could be achieved after approximately 11 cases, leading to stable surgical times. These findings serve as valuable guidance for novice gynecologists interested in adopting single-incision laparoscopy.


Assuntos
Laparoscopia , Curva de Aprendizado , Duração da Cirurgia , Salpingectomia , Humanos , Feminino , Estudos Retrospectivos , Laparoscopia/métodos , Laparoscopia/educação , Salpingectomia/métodos , Salpingectomia/educação , Adulto , Gravidez , Gravidez Tubária/cirurgia , Competência Clínica
6.
Epigenetics ; 18(1): 2175565, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36908025

RESUMO

Platinum-based chemotherapy is one of the predominant strategies for treating ovarian cancer (OC), however, platinum resistance greatly influences the therapeutic effect. Circular RNAs (circRNAs) have been found to participate in the pathogenesis of platinum resistance. Our aim was to explore the involvement of circ_0078607 in OC cell cisplatin (DDP) resistance and its potential mechanisms. Circ_0078607, miR-196b-5p, and growth arrest-specific 7 (GAS7) levels were assessed by qPCR. Circ_0078607 stability was assessed by ribonuclease R digestion and actinomycin D treatment. Cell viability of various conic of DDP treatment was measured by CCK-8. The cell proliferation was determined by CCK-8 and colony formation assay. Western blotting was performed for determining GAS7, ABCB1, CyclinD1 and Bcl-2 protein levels. The direct binding between miR-196b-5p and circ_0078607 or GAS7 was validated by dual-luciferase reporter and RIP assay. DDP resistance in vivo was evaluated in nude mice. Immunohistochemistry staining for detecting Ki67 expression in xenograft tumours. Circ_0078607 and GAS7 was down-regulated, but miR-196b-5p was up-regulated in OC samples and DDP-resistant cells. Overexpression of circ_0078607 inhibited DDP resistance, cell growth and induced apoptosis in DDP-resistant OC cells. Mechanistically, circ_0078607 sequestered miR-196b-5p to up-regulate GAS7. MiR-196b-5p mimics reversed circ_0078607 or GAS7 overexpression-mediated enhanced sensitivity. Finally, circ_0078607 improved the sensitivity of DDP in vivo. Circ_0078607 attenuates DDP resistance via miR-196b-5p/GAS7 axis, which highlights the therapeutic potential of circ_0078607 to counter DDP resistance in OC.


Assuntos
MicroRNAs , Proteínas do Tecido Nervoso , Neoplasias Ovarianas , Platina , RNA Circular , Animais , Feminino , Humanos , Camundongos , Proliferação de Células , Cisplatino , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos , Camundongos Nus , MicroRNAs/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Platina/farmacologia , RNA Circular/genética
7.
Oncogene ; 42(47): 3491-3502, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37828220

RESUMO

Cell senescence deters the activation of various oncogenes. Induction of senescence is, therefore, a potentially effective strategy to interfere with vital processes in tumor cells. Sphingosine-1-phosphate receptor 1 (S1PR1) has been implicated in various cancer types, including ovarian cancer. The mechanism by which S1PR1 regulates ovarian cancer cell senescence is currently elusive. In this study, we demonstrate that S1PR1 was highly expressed in human ovarian cancer tissues and cell lines. S1PR1 deletion inhibited the proliferation and migration of ovarian cancer cells. S1PR1 deletion promoted ovarian cancer cell senescence and sensitized ovarian cancer cells to cisplatin chemotherapy. Exposure of ovarian cancer cells to sphingosine-1-phosphate (S1P) increased the expression of 3-phosphatidylinositol-dependent protein kinase 1 (PDK1), decreased the expression of large tumor suppressor 1/2 (LATS1/2), and induced phosphorylation of Yes-associated protein (p-YAP). Opposite results were obtained in S1PR1 knockout cells following pharmacological inhibition. After silencing LATS1/2 in S1PR1-deficient ovarian cancer cells, senescence was suppressed and S1PR1 expression was increased concomitantly with YAP expression. Transcriptional regulation of S1PR1 by YAP was confirmed by chromatin immunoprecipitation. Accordingly, the S1PR1-PDK1-LATS1/2-YAP pathway regulates ovarian cancer cell senescence and does so through a YAP-mediated feedback loop. S1PR1 constitutes a druggable target for the induction of senescence in ovarian cancer cells. Pharmacological intervention in the S1PR1-PDK1-LATS1/2-YAP signaling axis may augment the efficacy of standard chemotherapy.


Assuntos
Neoplasias Ovarianas , Proteínas Quinases , Feminino , Humanos , Receptores de Esfingosina-1-Fosfato/genética , Neoplasias Ovarianas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Senescência Celular/genética , Proliferação de Células/genética
8.
BMC Cancer ; 12: 330, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22852778

RESUMO

BACKGROUND: Hyperfibrinogenemia is a common problem associated with various carcinomas, and is accompanied by hypercoagulablity. In advanced non-small-cell lung cancer (NSCLC) it remains unclear whether or not chemotherapy-induced changes in fibrinogen level relate to chemotherapeutic response and prognosis. The purposes of this study were to: 1) analyze the association between chemotherapy-induced changes in plasma fibrinogen level and the chemotherapeutic response after the first two courses of standard first-line platinum-based chemotherapy; and 2) evaluate the prognostic significance of the basal plasma fibrinogen level in patients with advanced NSCLC. METHODS: In this retrospective study, the data from 160 patients with advanced NSCLC were collected. The association between the changes in fibrinogen and the response to chemotherapy, or between the pre-and post-chemotherapy fibrinogen levels and patient clinical characteristics, were analyzed using SPSS software. In addition, the prognostic value of pre-chemotherapy fibrinogen levels was assessed. RESULTS: The median pre-chemotherapy plasma fibrinogen level was 4.4 g/L. Pre-chemotherapy plasma fibrinogen levels correlated significantly with gender (p = 0.041). Post-chemotherapy plasma fibrinogen levels correlated with gender (p = 0.023), age (p = 0.018), ECOG (p = 0.002) and tumor response (p = 0.049). Plasma fibrinogen levels markedly decreased after chemotherapy in 98 (61.25 %) patients with pre-chemotherapy hyperfibrinogenemia (p = 0.008); and in this population there was a significant link between the decrease in fibrinogen level, and initial partial response (PR; p = 0.017) and stable disease (SD; p = 0.031). Univariate and multivariate analysis revealed that higher levels of fibrinogen (≥4.4 g/L) and ECOG 1 were positively associated with shorter overall survival (OS). CEA and CA125 also decreased significantly (p =0.015, p =0.000) in DCR group after chemotherapy. CONCLUSIONS: This study showed that the reduction in plasma fibrinogen levels induced by chemotherapy might be as a promising biomarker as CEA and CA125 for evaluating the efficacy of chemotherapy in advanced NSCLC. In addition, basal plasma fibrinogen levels could be used as an independent prognostic parameter for the OS of patients with advanced NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Fibrinogênio/metabolismo , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Análise de Variância , Antineoplásicos/uso terapêutico , Antígeno Ca-125/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
9.
Clin Transl Med ; 12(1): e703, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073459

RESUMO

BACKGROUND: Chemoresistance to cisplatin (DDP) remains a major challenge in advanced gastric cancer (GC) treatment. Although accumulating evidence suggests an association between dysregulation of long non-coding RNAs (lncRNAs) and chemoresistance, the regulatory functions and complexities of lncRNAs in modulating DDP-based chemotherapy in GC remain under-investigated. This study was designed to explore the critical chemoresistance-related lncRNAs in GC and identify novel therapeutic targets for patients with chemoresistant GC. METHODS: Chemoresistance-related lncRNAs were identified through microarray and verified through a quantitative real-time polymerase chain reaction (qRT-PCR). Proteins bound by lncRNAs were identified through a human proteome array and validated through RNA immunoprecipitation (RIP) and RNA pull-down assays. Co-immunoprecipitation and ubiquitination assays were performed to explore the molecular mechanisms of the Musashi2 (MSI2) post-modification. The effects of LINC00942 (LNC942) and MSI2 on DDP-based chemotherapy were investigated through MTS, apoptosis assays and xenograft tumour formation in vivo. RESULTS: LNC942 was found to be up-regulated in chemoresistant GC cells, and its high expression was positively correlated with the poor prognosis of patients with GC. Functional studies indicated that LNC942 confers chemoresistance to GC cells by impairing apoptosis and inducing stemness. Mechanically, LNC942 up-regulated the MSI2 expression by preventing its interaction with SCFß-TRCP E3 ubiquitin ligase, eventually inhibiting ubiquitination. Then, LNC942 stabilized c-Myc mRNA in an N6-methyladenosine (m6 A)-dependent manner. As a potential m6 A recognition protein, MSI2 stabilized c-Myc mRNA with m6 A modifications. Moreover, inhibition of the LNC942-MSI2-c-Myc axis was found to restore chemosensitivity both in vitro and in vivo. CONCLUSIONS: These results uncover a chemoresistant accelerating function of LNC942 in GC, and disrupting the LNC942-MSI2-c-Myc axis could be a novel therapeutic strategy for GC patients undergoing chemoresistance.


Assuntos
Cisplatino/metabolismo , Resistência a Medicamentos/efeitos dos fármacos , Genes myc/efeitos dos fármacos , RNA Longo não Codificante/agonistas , Proteínas de Ligação a RNA/antagonistas & inibidores , Cisplatino/uso terapêutico , Genes myc/fisiologia , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/uso terapêutico , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética
10.
Nat Commun ; 13(1): 3034, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641493

RESUMO

Abnormal neddylation activation is frequently observed in human cancers and neddylation inhibition has been proposed as a therapy for cancer. Here, we report that MLN4924, a small-molecule inhibitor of neddylation activating enzyme, increases glutamine uptake in breast cancer cells by causing accumulation of glutamine transporter ASCT2/SLC1A5, via inactivation of CRL3-SPOP E3 ligase. We show the E3 ligase SPOP promotes ASCT2 ubiquitylation, whereas SPOP itself is auto-ubiquitylated upon glutamine deprivation. Thus, SPOP and ASCT2 inversely regulate glutamine uptake and metabolism. SPOP knockdown increases ASCT2 levels to promote growth which is rescued by ASCT2 knockdown. Adding ASCT2 inhibitor V-9302 enhances MLN4924 suppression of tumor growth. In human breast cancer specimens, SPOP and ASCT2 levels are inversely correlated, whereas lower SPOP with higher ASCT2 predicts a worse patient survival. Collectively, our study links neddylation to glutamine metabolism via the SPOP-ASCT2 axis and provides a rational drug combination for enhanced cancer therapy.


Assuntos
Neoplasias da Mama , Proteínas Nucleares , Proteínas Repressoras , Ubiquitina-Proteína Ligases , Sistema ASC de Transporte de Aminoácidos/genética , Sistema ASC de Transporte de Aminoácidos/metabolismo , Linhagem Celular Tumoral , Feminino , Glutamina/metabolismo , Humanos , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
11.
Cancer Gene Ther ; 29(12): 1895-1907, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35864225

RESUMO

Epigenetic alterations have been functionally linked to ovarian cancer development and occurrence. The CXXC zinc finger protein 1 (CFP1) is an epigenetic regulator involved in DNA methylation and histone modification in mammalian cells. However, its role in ovarian cancer cells is unknown. Here, we show that CFP1 protein is highly expressed in human ovarian cancer tissues. Loss of CFP1 inhibited the growth of human ovarian cancer cells, promoted apoptosis, and increased senescence. CFP1 knockdown resulted in reduced levels of SETD1 (a CFP1 partner) and histone H3 trimethylation at the fourth lysine residue (H3K4me3). RNA-sequencing revealed that deletion of CFP1 resulted in mRNA reduction of bone marrow stromal cell antigen 2 (BST2). Bioinformatics analysis and chromatin immunoprecipitation showed that CFP1 binds to the promoter of BST2 and regulates its transcription directly. Overexpression of BST2 rescued the growth inhibitory effect of CFP1 loss. Furthermore, depletion of cullin-RING ubiquitin ligases 4 (CRL4) components ROC1 or CUL4A had significantly inhibited the expression of CFP1 and BST2 similar to MLN4924 treatment that blocked cullin neddylation and inactivated CRL4s. In conclusion, CFP1 promotes ovarian cancer cell proliferation and apoptosis by regulating the transcription of BST2, and the expression of CFP1 was affected by CRL4 ubiquitin ligase complex.


Assuntos
Antígenos CD , Neoplasias Ovarianas , Transativadores , Feminino , Humanos , Antígenos CD/genética , Proliferação de Células/genética , Proteínas Culina , Proteínas Ligadas por GPI/genética , Neoplasias Ovarianas/genética , Transativadores/genética , Ubiquitinas
12.
Cell Biosci ; 11(1): 55, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731189

RESUMO

Mitochondria are the powerhouse of a cell. The structure and function of mitochondria are precisely regulated by multiple signaling pathways. Neddylation, a post-translational modification, plays a crucial role in various cellular processes including cellular metabolism via modulating the activity, function and subcellular localization of its substrates. Recently, accumulated data demonstrated that neddylation is involved in regulation of morphology, trafficking and function of mitochondria. Mechanistic elucidation of how mitochondria is modulated by neddylation would further our understanding of mitochondrial regulation to a new level. In this review, we first briefly introduce mitochondria, then neddylation cascade, and known protein substrates subjected to neddylation modification. Next, we summarize current available data of how neddylation enzymes, its substrates (including cullins/Cullin-RING E3 ligases and non-cullins) and its inhibitor MLN4924 regulate the structure and function of mitochondria. Finally, we propose the future perspectives on this emerging and exciting field of mitochondrial research.

13.
Clin Transl Med ; 11(10): e587, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34709767

RESUMO

Chemoresistance remains a major obstacle to successful cancer therapy, especially for advanced cancers. It used to be recognised as a stable outcome resulting from genetic changes. However, recent studies showed that chemoresistance can also be unstable and reversible with the involvement of non-genetic alterations. In the present study, we found that activating transcription factor 4 (ATF4) is downregulated in chemoresistant gastric cancer cells. The over-expression of ATF4 reversed chemoresistance by activating CHOP transcription to enhance drug-induced apoptosis, and vice versa. Moreover, casein kinase 1 delta (CK1δ) was identified as the kinase responsible for ATF4-S219 phosphorylation, which triggered ßTrCP-mediated ATF4 polyubiquitination to promote its proteasomal degradation subsequently. Interestingly, drug withdrawal gradually restored chemosensitivity as well as ATF4 expression in chemoresistant cells, highlighting the dependence of dynamic drug resistance on ATF4 protein expression. In line with these findings, the inhibition of ATF4 protein degradation by CK1δ or proteasome inhibitors overcame chemoresistance both in vitro and in vivo. Taken together, these results indicate that CK1δ stimulates ßTrCP-dependent ATF4 polyubiquitination and subsequent proteasomal degradation to promote chemoresistance in gastric cancer. Stabilisation of the ATF4 protein with bortezomib (BTZ), an anticancer drug that inhibits proteasomal degradation, might be a rational strategy to improve chemotherapeutic efficacy in gastric cancer.


Assuntos
Fator 4 Ativador da Transcrição/genética , Caseína Quinase Idelta/genética , Caseína Quinase Idelta/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Ubiquitinação/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Complexo de Endopeptidases do Proteassoma
14.
Cell Death Dis ; 12(4): 405, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854041

RESUMO

p62/SQSTM1 is frequently up-regulated in many cancers including hepatocellular carcinoma. Highly expressed p62 promotes hepato-carcinogenesis by activating many signaling pathways including Nrf2, mTORC1, and NFκB signaling. However, the underlying mechanism for p62 up-regulation in hepatocellular carcinoma remains largely unclear. Herein, we confirmed that p62 was up-regulated in hepatocellular carcinoma and its higher expression was associated with shorter overall survival in patients. The knockdown of p62 in hepatocellular carcinoma cells decreased cell growth in vitro and in vivo. Intriguingly, p62 protein stability could be reduced by its acetylation at lysine 295, which was regulated by deacetylase Sirt1 and acetyltransferase GCN5. Acetylated p62 increased its association with the E3 ligase Keap1, which facilitated its poly-ubiquitination-dependent proteasomal degradation. Moreover, Sirt1 was up-regulated to deacetylate and stabilize p62 in hepatocellular carcinoma. Additionally, Hepatocyte Sirt1 conditional knockout mice developed much fewer liver tumors after Diethynitrosamine treatment, which could be reversed by the re-introduction of exogenous p62. Taken together, Sirt1 deacetylates p62 at lysine 295 to disturb Keap1-mediated p62 poly-ubiquitination, thus up-regulating p62 expression to promote hepato-carcinogenesis. Therefore, targeting Sirt1 or p62 is a reasonable strategy for the treatment of hepatocellular carcinoma.


Assuntos
Carcinogênese/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Sirtuína 1/metabolismo , Animais , Autofagia/fisiologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos Endogâmicos BALB C , Processamento de Proteína Pós-Traducional/fisiologia , Transdução de Sinais/fisiologia
15.
Front Cell Dev Biol ; 9: 741736, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34977006

RESUMO

Hypoxia is an important characteristic of the tumor microenvironment. Tumor cells can survive and propagate under the hypoxia stress by activating a series of adaption response. Herein, we found that lysine-specific demethylase 5B (KDM5B) was upregulated in gastric cancer (GC) under hypoxia conditions. The genetic knockdown or chemical inhibition of KDM5B impaired the growth of GC cell adapted to hypoxia. Interestingly, the upregulation of KDM5B in hypoxia response was associated with the SUMOylation of KDM5B. SUMOylation stabilized KDM5B protein by reducing the competitive modification of ubiquitination. Furthermore, the protein inhibitor of activated STAT 4 (PIAS4) was determined as the SUMO E3 ligase, showing increased interaction with KDM5B under hypoxia conditions. The inhibition of KDM5B caused significant downregulation of hypoxia-inducible factor-1α (HIF-1α) protein and target genes under hypoxia. As a result, co-targeting KDM5B significantly improved the antitumor efficacy of antiangiogenic therapy in vivo. Taken together, PIAS4-mediated SUMOylation stabilized KDM5B protein by disturbing ubiquitination-dependent proteasomal degradation to overcome hypoxia stress. Targeting SUMOylation-dependent KDM5B upregulation might be considered when the antiangiogenic therapy was applied in cancer treatment.

16.
Cancer Manag Res ; 12: 10461-10468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122945

RESUMO

BACKGROUND: This study was to investigate the prognostic factors of patients with advanced gastric cancer and described a sample model to better differentiate the patients who could better benefit from palliative chemotherapy. PATIENTS AND METHODS: In this retrospective study, 112 gastric cancer patients at stage IV following first-line chemotherapy were enrolled from July 2013 to September 2019. The clinical factors including age, sex, ECOG, pathologic types, metastatic sites, blood indexes, response of first-line chemotherapy, and survival were collected. The treatment responses were evaluated using the response evaluation criteria in solid tumors (RECIST). The survival curves were drawn by the Kaplan-Meier method, and the independent prognostic factors of overall survival (OS) were analyzed by Cox proportional hazards regression model. RESULTS: In this study, the median overall survival (mOS) of gastric cancer patients was 10.5 months, the disease remission rate (PR) was 21.4%, and the disease control rate (DCR) was 86.6%. Multivariate analysis identified 5 independent prognostic factors: peritoneal metastasis [P = 0.002; hazard risk (HR), 2.394; 95% CI 1.394-4.113], hemoglobin <90g/L [P = 0.001; hazard risk (HR), 2.674; 95% CI 1.536-4.655], LDH ≥225 U/L [P = 0.033; hazard risk (HR), 1.818; 95% CI 1.409-3.150], and 3 times higher level of CEA [P = 0.006; hazard risk (HR), 2.123; 95% CI 1.238-3.640] along with CA199 [P = 0.005; hazard risk (HR), 2.544; 95% CI 1.332-4.856] than upper limit of normal. Based on the obtained data, a prognostic index was constructed, dividing the patients into three risk groups: low (n = 67), intermediate (n = 35), and high-risk group (n = 10). The mOS for low, intermediate, and high-risk groups was 13.9 months (95% CI 10.7-17.1), 8.1 months (95% CI 5.7-10.4), and 3.9 months (95% CI 2.6-5.3), respectively, whereas the 1-year survival rate was 56.4%, 20.0%, and 0.0%, respectively (P < 0.001). CONCLUSION: This model should facilitate the prediction of treatment outcomes and then individualized treatment of advanced gastric cancer patients.

17.
Am J Cancer Res ; 10(10): 3106-3126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163260

RESUMO

Amino acid transporters mediate substrates across cellular membranes and their fine-tuned regulations are critical to cellular metabolism, growth, and death. As the functional component of system Xc-, which imports extracellular cystine with intracellular glutamate release at a ratio of 1:1, SLC7A11 has diverse functional roles in regulating many pathophysiological processes such as cellular redox homeostasis, ferroptosis, and drug resistance in cancer. Notably, accumulated evidence demonstrated that SLC7A11 is overexpressed in many types of cancers and is associated with patients' poor prognosis. As a result, SLC7A11 becomes a new potential target for cancer therapy. In this review, we first briefly introduce the structure and function of SLC7A11, then discuss its pathological role in cancer. We next summarize current available data of how SLC7A11 is subjected to fine regulations at multiple levels. We further describe the potential inhibitors of the SLC7A11 and their roles in human cancer cells. Finally, we propose novel insights for future perspectives on the modulation of SLC7A11, as well as possible targeted strategies for SLC7A11-based anti-cancer therapies.

18.
Int J Biol Sci ; 16(7): 1194-1206, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174794

RESUMO

Metabolic reprogramming is a hallmark of cancer. Mammalian genome is characterized by pervasive transcription, generating abundant non-coding RNAs (ncRNAs). Long non-coding RNAs (lncRNAs) are freshly discovered functional ncRNAs exerting extensive regulatory impact through diverse mechanisms. Emerging studies have revealed widespread roles of lncRNAs in the regulation of various cellular activities, including metabolic pathways. In this review, we summarize the latest advances regarding the regulatory roles of lncRNAs in cancer metabolism, particularly their roles in mitochondrial function, glucose, glutamine, and lipid metabolism. Moreover, we discuss the clinical application and challenges of targeting lncRNAs in cancer metabolism. Understanding the complex and special behavior of lncRNAs will allow a better depiction of cancer metabolic networks and permit the development of lncRNA-based clinical therapies by targeting cancer metabolism.


Assuntos
Neoplasias/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Humanos , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Neoplasias/genética , RNA Longo não Codificante/genética
19.
Toxicol In Vitro ; 23(3): 408-17, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19344684

RESUMO

1-hydroxy-3,7,8-trimethoxyxanthone (xanthone 1) was isolated from Gentianopsis paludosa Ma and identified by MS and NMR in our laboratory. In this study, the results showed that xanthone 1 is a potent inducer of anti-proliferation and apoptosis in HL-60 cells. When the cells treated with lower concentrations of xanthone 1 (12.4-74.4microM), significant proliferation inhibition was detected by cell viability assay and morphological analyses, and conspicuous G1 and G2/M cell cycle arrest were observed by flow cytometric (FCM) analysis. However, when the cells treated with higher doses of xanthone 1 (82.7-330.8microM), significant apoptosis was observed by double sequential AO/EB staining, DNA fragmentation assay and FCM analysis. In addition, conspicuous DNA damage was detected by comet assay. In short, all the results showed that xanthone 1 had a significant cytotoxic effect and could induce proliferation inhibition and apoptosis in HL-60 cells in a time- and dose-dependent manner. It was possible that xanthone 1 could induce DNA damage in HL-60 cells, which resulted in G1 phase arrest at the lower concentrations and G2/M phase arrest at the higher concentrations, thus inhibiting the cell proliferation, and irreparable DNA damage at the higher concentrations might be responsible for the occurrence of apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gentianaceae/química , Leucemia Promielocítica Aguda/patologia , Plantas Medicinais/química , Xantonas/farmacologia , Antineoplásicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Extratos Vegetais/farmacologia , Tibet , Xantonas/isolamento & purificação
20.
Mol Cell Oncol ; 6(5): e1618174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528694

RESUMO

MLN4924, a small molecular inhibitor of NEDD8 (neuronal precursor cell-expressed developmentally downregulated protein 8) activating enzyme (NAE), blocks cullin neddylation to inactivate cullin-RING ligase. We found that MLN4924 has additional activities: it triggers EGFR dimerization and activation of RAS/MAPK and PI3K/AKT1 signals to stimulate tumor sphere formation and inhibit ciliogenesis; and it triggers PKM2 tetramerization to promote glycolysis.

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