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1.
EBioMedicine ; 71: 103558, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34521054

RESUMO

BACKGROUND: Resistance to platinum-based chemotherapy is a major cause of therapeutic failure during the treatment of epithelial ovarian cancer (EOC) patients. Our study aims to elucidate the molecular mechanisms by which ZNF711 down regulation promotes CISPLATIN resistance in EOC. METHODS: ZNF711 expression in 150 EOC specimens was examined using immunohistochemistry. ZNF711 expression and the survival of EOC patients were assessed with a Kaplan-Meier analysis. The effects of ZNF711 expression on CDDP resistance were studied by IC50, Annexin V, and colony formation in vitro, and in an in vivo intra-peritoneal tumor model. The molecular mechanism was determined using a luciferase reporter assay, ChIP assay, CAPTURE approach, and co-IP assay. FINDINGS: ZNF711 down-regulation exerts a great impact on CDDP resistance for EOC patients by suppressing SLC31A1 and inhibiting CDDP influx. ZNF711 down-regulation promoted, while ZNF711 overexpression drastically inhibited CDDP resistance, both in vivo and in vitro. Mechanistically, the histone demethylase JHDM2A was recruited to the SLC31A1 promoter by ZNF711 and decreased the H3K9me2 level, resulting in the activation of SLC31A1 transcription and enhancement of CDDP uptake. Importantly, co-treatment with the histone methylation inhibitor, BIX-01294, increased the therapeutic efficacy of CDDP treatment in ZNF711-suppressed EOC cells. INTERPRETATION: These findings both verified the clinical importance of ZNF711 in CDDP resistance and provide novel therapeutic regimens for EOC treatment. FUNDING: This work was supported by the Natural Science Foundation of China; Guangzhou Science and Technology Plan Projects; Natural Science Foundation of Guangdong Province; The Fundamental Research Funds for the Central Universities; and China Postdoctoral Science Foundation.

3.
Mol Cancer ; 20(1): 98, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325714

RESUMO

BACKGROUND: Breast cancer (BC) has a marked tendency to spread to the bone, resulting in significant skeletal complications and mortality. Recently, circular RNAs (circRNAs) have been reported to contribute to cancer initiation and progression. However, the function and mechanism of circRNAs in BC bone metastasis (BC-BM) remain largely unknown. METHODS: Bone-metastatic circRNAs were screened using circRNAs deep sequencing and validated using in situ hybridization in BC tissues with or without bone metastasis. The role of circIKBKB in inducing bone pre-metastatic niche formation and bone metastasis was determined using osteoclastogenesis, immunofluorescence and bone resorption pit assays. The mechanism underlying circIKBKB-mediated activation of NF-κB/bone remodeling factors signaling and EIF4A3-induced circIKBKB were investigated using RNA pull-down, luciferase reporter, chromatin isolation by RNA purification and enzyme-linked immunosorbent assays. RESULTS: We identified that a novel circRNA, circIKBKB, was upregulated significantly in bone-metastatic BC tissues. Overexpressing circIKBKB enhanced the capability of BC cells to induce formation of bone pre-metastatic niche dramatically by promoting osteoclastogenesis in vivo and in vitro. Mechanically, circIKBKB activated NF-κB pathway via promoting IKKß-mediated IκBα phosphorylation, inhibiting IκBα feedback loop and facilitating NF-κB to the promoters of multiple bone remodeling factors. Moreover, EIF4A3, acted acting as a pre-mRNA splicing factor, promoted cyclization of circIKBKB by directly binding to the circIKBKB flanking region. Importantly, treatment with inhibitor eIF4A3-IN-2 reduced circIKBKB expression and inhibited breast cancer bone metastasis effectively. CONCLUSION: We revealed a plausible mechanism for circIKBKB-mediated NF-κB hyperactivation in bone-metastatic BC, which might represent a potential strategy to treat breast cancer bone metastasis.

4.
Cancer Res ; 81(14): 3835-3848, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34049973

RESUMO

Mitochondrial dynamics play vital roles in the tumorigenicity and malignancy of various types of cancers by promoting the tumor-initiating potential of cancer cells, suggesting that targeting crucial factors that drive mitochondrial dynamics may lead to promising anticancer therapies. In the current study, we report that overexpression of mitochondrial fission factor (MFF), which is upregulated significantly in liver cancer-initiating cells (LCIC), promotes mitochondrial fission and enhances stemness and tumor-initiating capability in non-LCICs. MFF-induced mitochondrial fission evoked mitophagy and asymmetric stem cell division and promoted a metabolic shift from oxidative phosphorylation to glycolysis that decreased mitochondrial reactive oxygen species (ROS) production, which prevented ROS-mediated degradation of the pluripotency transcription factor OCT4. CRISPR affinity purification in situ of regulatory elements showed that T-box transcription factor 19 (TBX19), which is overexpressed uniquely in LCICs compared with non-LCICs and liver progenitor cells, forms a complex with PRMT1 on the MFF promoter in LCICs, eliciting epigenetic histone H4R3me2a/H3K9ac-mediated transactivation of MFF. Targeting PRMT1 using furamidine, a selective pharmacologic inhibitor, suppressed TBX19-induced mitochondrial fission, leading to a profound loss of self-renewal potential and tumor-initiating capacity of LCICs. These findings unveil a novel mechanism underlying mitochondrial fission-mediated cancer stemness and suggest that regulation of mitochondrial fission via inhibition of PRMT1 may be an attractive therapeutic option for liver cancer treatment. SIGNIFICANCE: These findings show that TBX19/PRMT1 complex-mediated upregulation of MFF promotes mitochondrial fission and tumor-initiating capacity in liver cancer cells, identifying PRMT1 as a viable therapeutic target in liver cancer.

5.
Adv Sci (Weinh) ; 8(4): 2001961, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33643786

RESUMO

The incidence of bone metastases in hepatocellular carcinoma (HCC) has increased prominently over the past decade owing to the prolonged overall survival of HCC patients. However, the mechanisms underlying HCC bone-metastasis remain largely unknown. In the current study, HCC-secreted lectin galactoside-binding soluble 3 (LGALS3) is found to be significantly upregulated and correlates with shorter bone-metastasis-free survival of HCC patients. Overexpression of LGALS3 enhances the metastatic capability of HCC cells to bone and induces skeletal-related events by forming a bone pre-metastatic niche via promoting osteoclast fusion and podosome formation. Mechanically, ubiquitin ligaseRNF219-meidated α-catenin degradation prompts YAP1/ß-catenin complex-dependent epigenetic modifications of LGALS3 promoter, resulting in LGALS3 upregulation and metastatic bone diseases. Importantly, treatment with verteporfin, a clinical drug for macular degeneration, decreases LGALS3 expression and effectively inhibits skeletal complications of HCC. These findings unveil a plausible role for HCC-secreted LGALS3 in pre-metastatic niche and can suggest a promising strategy for clinical intervention in HCC bone-metastasis.

6.
Nat Commun ; 10(1): 3761, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434880

RESUMO

The mechanisms underlying how cells subjected to genotoxic stress reestablish reduction-oxidation (redox) homeostasis to scavenge genotoxic stress-induced reactive oxygen species (ROS), which maintains the physiological function of cellular processes and cell survival, remain unclear. Herein, we report that, via a TCF-independent mechanism, genotoxic stress induces the enrichment of ß-catenin in chromatin, where it forms a complex with ATM phosphorylated-JDP2 and PRMT5. This elicits histone H3R2me1/H3R2me2s-induced transcriptional activation by the recruitment of the WDR5/MLL methyltransferase complexes and concomitant H3K4 methylation at the promoters of multiple genes in GSH-metabolic cascade. Treatment with OICR-9429, a small-molecule antagonist of the WDR5-MLL interaction, inhibits the ß-catenin/JDP2/PRMT5 complex-reestablished GSH metabolism, leading to a lethal increase in the already-elevated levels of ROS in the genotoxic-agent treated cancer cells. Therefore, our results unveil a plausible role for ß-catenin in reestablishing redox homeostasis upon genotoxic stress and shed light on the mechanisms of inducible chemotherapy resistance in cancer.


Assuntos
Dano ao DNA/fisiologia , Glutationa/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , beta Catenina/metabolismo , Células A549 , Animais , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Cromatina , Di-Hidropiridinas/farmacologia , Feminino , Glutationa/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Homeostase , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteína de Leucina Linfoide-Mieloide/metabolismo , Neoplasias/metabolismo , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ativação Transcricional
7.
EBioMedicine ; 43: 238-252, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31047858

RESUMO

BACKGROUND: Aberrant fatty acid (FA) metabolism is a unique vulnerability of cancer cells and may present a promising target for cancer therapy. Our study aims to elucidate the molecular mechanisms by which NKX2-8 deletion reprogrammed FA metabolism-induced chemoresistance in epithelial ovarian cancer (EOC). METHODS: The deletion frequency and expression of NKX2-8 in 144 EOC specimens were assayed using Fluorescence in situ hybridization and immunochemical assays. The effects of NKX2-8 deletion and the fatty acid oxidation (FAO) antagonist Perhexiline on chemoresistance were examined by Annexin V and colony formation in vitro, and via an intraperitoneal tumor model in vivo. The mechanisms of NKX2-8 deletion in reprogrammed FA metabolism was determined using Chip-seq, metabolomic analysis, FAO assays and immunoprecipitation assays. FINDINGS: NKX2-8 deletion was correlated with the overall and relapse-free survival of EOC patients. NKX2-8 inhibited the FAO pathway by epigenetically suppressing multiple key components of the FAO cascade, including CPT1A and CPT2. Loss of NKX2-8 resulted in reprogramming of FA metabolism of EOC cells in an adipose microenvironment and leading to platinum resistance. Importantly, pharmacological inhibition of FAO pathway using Perhexiline significantly counteracted NKX2-8 deletion-induced chemoresistance and enhanced platinum's therapeutic efficacy in EOC. INTERPRETATION: Our results demonstrate that NKX2-8 deletion-reprogrammed FA metabolism contributes to chemoresistance and Perhexiline might serve as a potential tailored treatment for patients with NKX2-8-deleted EOC. FUND: This work was supported by Natural Science Foundation of China; Guangzhou Science and Technology Plan Projects; Natural Science Foundation of Guangdong Province; The Fundamental Research Funds for the Central Universities.


Assuntos
Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Ácidos Graxos/metabolismo , Proteínas de Homeodomínio/genética , Deleção de Sequência , Fatores de Transcrição/genética , Animais , Biomarcadores , Carcinoma Epitelial do Ovário/mortalidade , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Camundongos , Modelos Biológicos , Oxirredução , Prognóstico , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Microambiente Tumoral
8.
Clin Cancer Res ; 25(3): 1022-1035, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30279231

RESUMO

PURPOSE: The development of resistance to platinum-based chemotherapy remains the unsurmountable obstacle in cancer treatment and consequently leads to tumor relapse. This study aims to investigate the mechanism by which loss of RBMS3 induced chemoresistance in epithelial ovarian cancer (EOC). EXPERIMENTAL DESIGN: FISH and IHC were used to determine deletion frequency and expression of RBMS3 in 15 clinical EOC tissues and 150 clinicopathologically characterized EOC specimens. The effects of RBMS3 deletion and CBP/ß-catenin antagonist PRI-724 in chemoresistance were examined by clone formation and Annexin V assays in vitro, and by intraperitoneal tumor model in vivo. The mechanism by which RBMS3 loss sustained activation of miR-126-5p/ß-catenin/CBP signaling and the effects of RBMS3 and miR-126-5p competitively regulating DKK3, AXIN1, BACH1, and NFAT5 was explored using CLIP-seq, RIP, electrophoretic mobility shift, and immunoblotting and immunofluorescence assays. RESULTS: Loss of RBMS3 in EOC was correlated with the overall and relapse-free survival. Genetic ablation of RBMS3 significantly enhanced, whereas restoration of RBMS3 reduced, the chemoresistance ability of EOC cells both in vitro and in vivo. RBMS3 inhibited ß-catenin/CBP signaling through directly associating with and stabilizing multiple negative regulators, including DKK3, AXIN1, BACH1, and NFAT5, via competitively preventing the miR-126-5p-mediated repression of these transcripts. Importantly, cotherapy of CBP/ß-catenin antagonist PRI-724 induced sensitization of RBMS3-deleted EOC to platinum therapy. CONCLUSIONS: Our results demonstrate that genetic ablation of RBMS3 contributes to chemoresistance and PRI-724 may serve as a potential tailored treatment for patients with RBMS3-deleted EOC.


Assuntos
Carcinoma Epitelial do Ovário/genética , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , MicroRNAs/genética , Fragmentos de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Sialoglicoproteínas/genética , Transativadores/genética , beta Catenina/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/patologia , Cisplatino/administração & dosagem , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Pirimidinonas/administração & dosagem , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transativadores/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Oncogene ; 38(15): 2736-2749, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30542119

RESUMO

Tumor-associated lymphangiogenesis has attracted increasing attention because of its potential contribution to lymph node metastasis. However, the molecular mechanisms underlying lymphangiogenesis in cancer remains elusive. In the current study, we demonstrate that tripartite motif-containing 3 (TRIM3) directly interacts with and induces E3 ligase-dependent proteasomal turnover of importin α3 and α-Actinin-4 (ACTN4), which controls nuclear factor kappa B (NF-κB) activity at a well-ordered level. Heterozygous deletion-mediated TRIM3 downregulation led to NF-κB constitutive activation through disruption of the NF-κB-IκB-α negative feedback loop and enhancement of the p65 DNA-binding affinity and transcriptional activity via promoting symmetrical dimethylarginine modification of NF-κB/p65 at Arg30 and Arg35, which consequently promoted lymphatic metastasis of esophageal squamous cell carcinoma (ESCC) cells. Treatment with Tecfidera, a medication used to treat multiple sclerosis, restored the negative feedback inhibition of NF-κB by reducing the NF-κB/ACTN4 interaction and decreasing symmetrically dimethylated NF-κB levels, resulting in inhibition of ESCC lymphatic metastasis both in vitro and in vivo. Taken together, our results uncover a novel mechanism for constitutive NF-κB activation in cancer and may represent an attractive strategy to treat ESCC lymphatic metastasis.


Assuntos
Proteínas de Transporte/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Linfangiogênese/genética , Metástase Linfática/genética , Metástase Linfática/patologia , Actinina/genética , Linhagem Celular , Neoplasias Esofágicas/patologia , Humanos , Inibidor de NF-kappaB alfa/genética , NF-kappa B/genética , Transdução de Sinais/genética
10.
Theranostics ; 8(13): 3571-3583, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026867

RESUMO

It has been reported that the transcription factor activating enhancer-binding protein 4 (TFAP4) is upregulated and associated with an aggressive phenotype in several cancers. However, the precise mechanisms underlying the oncogenic role of TFAP4 remain largely unknown. Methods: TFAP4 expression levels in hepatocellular carcinoma (HCC) cells and tissues were detected by quantitative real-time PCR (qPCR) and immunohistochemistry (IHC). In vitro and in vivo assays were performed to investigate the oncogenic function of TFAP4 in the tumor-initiating cell (TIC)-like phenotype and the tumorigenic capability of HCC cells. Luciferase reporter and chromatin immunoprecipitation (ChIP)-qPCR assays were performed to determine the underlying mechanism of TFAP4-mediated HCC aggressiveness. Results: TFAP4 was markedly upregulated in human HCC, and was associated with significantly poorer overall and relapse-free survival in patients with HCC. Furthermore, we found that overexpression of TFAP4 significantly enhanced, whereas silencing TFAP4 inhibited, the tumor sphere formation ability and proportion of side-population cells in HCC cells in vitro, and ectopic TFAP4 enhanced the tumorigenicity of HCC cells in vivo. Mechanistically, we demonstrated that TFAP4 played an important role in activating Wnt/ß-catenin signaling by directly binding to the promoters of DVL1 (dishevelled segment polarity protein 1) and LEF1 (lymphoid enhancer binding factor 1). Conclusions: Our results provide new insight into the mechanisms underlying hyperactivation of the Wnt/ß-catenin pathway in HCC, as well the oncogenic ability of TFAP4 to enhance the tumor-forming ability of HCC cells.


Assuntos
Carcinogênese , Carcinoma Hepatocelular/fisiopatologia , Proteínas de Ligação a DNA/metabolismo , Proteínas Desgrenhadas/metabolismo , Neoplasias Hepáticas/fisiopatologia , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Carcinoma Hepatocelular/patologia , Imunoprecipitação da Cromatina , Perfilação da Expressão Gênica , Genes Reporter , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/patologia , Luciferases/análise , Regiões Promotoras Genéticas , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
11.
Toxicol Lett ; 284: 103-112, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29248572

RESUMO

1,3-dichloro-2-propanol (1,3-DCP) is a widely concerned food processing contaminant which has been investigated for decades. While the neurotoxicity of 1,3-DCP and related mechanisms are still elusive. Herein, the effect of 1,3-DCP on neurotoxicity was investigated using BV-2 microglia cells. 1,3-DCP significantly decreased cell viability from 78.6% to 59.2% at doses between 2 and 20 mM. AO/EB and JC-1 staining indicated that 1,3-DCP induced apoptosis by means of the decrease of mitochondrial membrane potential. Meanwhile, western blot showed that 1,3-DCP stimulated inflammation of BV-2 cells through phosphorylation of MAPKs and activation of NF-κB pathways mediated by reactive oxygen species (ROS). Furthermore, the degree of inflammation and apoptosis has eased through MAPKs and NF-κB pathways with cells pretreated by N-acetylcysteine (NAC). Overall, these results presented here suggested that 1,3-DCP has neurotoxic effect on BV-2 microglia mainly via MAPKs and NF-κB pathways mediated by ROS.


Assuntos
Apoptose/efeitos dos fármacos , Microglia/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , alfa-Cloridrina/análogos & derivados , Acetilcisteína/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Contaminação de Alimentos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Microglia/imunologia , Microglia/patologia , Fosforilação , Transdução de Sinais , alfa-Cloridrina/toxicidade
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