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1.
Clin Immunol ; : 108872, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34648954

RESUMO

Ferroptosis is a novel form of cell death characterized by heavy iron accumulation and lipid peroxidation that plays a critical role in the tumor microenvironment. However, promising biomarkers associated with tumor immune cell infiltration and the immunotherapy response to ferroptosis regulators remain to be elucidated in lung adenocarcinoma (LUAD) patients. In this study, we defined ferroptosis regulators in LUAD through database analysis and experimental validation to determine the implementation of genes associated with clinical relevance, immunotherapy response and tumor microenvironment in LUAD patients. Multiomics data analysis was performed to explore the CNV features, molecular mechanisms and immunogenic characteristics of ferroptosis regulators in LUAD patients. Then, univariate and multivariate Cox regression analyses were used to identify three genes (DDIT4, RRM2, and SLC2A1) that were closely associated with the prognosis of LUAD patients. The prognostic model based on the determination of these three genes was an independent prognostic factor (p < 0.05, HR = 2.838), and patients with superior predictive performance and higher prognostic risk were more likely to have poor survival rates than those with lower prognostic risk in the training group (p < 0.001, HR = 3.19) and the test group (p < 0.001, HR = 2.94; p < 0.001, HR = 3.44). Activated immune cells, including T helper cells and activated CD8 T cells, were lower in the high-risk group, while type 2 T cells were higher (p < 0.05). Patients with higher prognostic risk were less likely to benefit from immunotherapy, partly due to low CTLA4 levels and an immunosuppressive microenvironment (p < 0.05). Combined with LUAD tissue samples and mouse trials, RRM2 was found to influence lung cancer progression and affect tumor immune cell infiltration. RRM2 inhibition effectively promoted M1 macrophage polarization and suppressed M2 macrophage polarization in vitro and in vivo. And ferroptosis inhibitor ferrostatin-1 treatment effectively re-blanced macrophage polarization mediated by RRM2 inhibition. Taken together, the results of the multiomics data analysis and experimental validation identified ferroptosis regulators as promising biomarkers and therapeutic targets associated with tumor immune infiltration in LUAD patients.

2.
Cell Prolif ; 54(8): e13088, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34240781

RESUMO

OBJECTIVES: Breast cancer-amplified sequence 3 (BCAS3) was initially found to be amplified in human breast cancer (BRCA); however, there has been little consensus on the functions of BCAS3 in breast tumours. MATERIALS AND METHODS: We analysed BCAS3 expression in BRCA using bio-information tools. Affinity purification and mass spectrometry were employed to identify BCAS3-associated proteins. GST pull-down and ubiquitination assays were performed to analyse the interaction mechanism between BCAS3/p53 and CUL4A-RING E3 ubiquitin ligase (CRL4A) complex. BCAS3 was knocked down individually or in combination with p53 in MCF-7 cells to further explore the biological functions of the BCAS3/p53 axis. The clinical values of BCAS3 for BRCA progression were evaluated via semiquantitative immunohistochemistry (IHC) analysis and Cox regression. RESULTS: We reported that the expression level of BCAS3 in BRCA was higher than that in adjacent normal tissues. High BCAS3 expression promoted growth, inhibited apoptosis and conferred chemoresistance in breast cancer cells. Mechanistically, BCAS3 overexpression fostered BRCA cell growth by interacting with the CRL4A complex and promoting ubiquitination and proteasomal degradation of p53. Furthermore, BCAS3 could regulate cell growth, apoptosis and chemoresistance through a p53-mediated mechanism. Clinically, BCAS3 overexpression was significantly correlated with a malignant phenotype. Moreover, higher expression of BCAS3 correlates with shorter overall survival (OS) in BRCA. CONCLUSIONS: The functional characterization of BCAS3 offers new insights into the oncogenic properties and chemotherapy resistance in breast cancer.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Neoplasias/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Apoptose , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Proteínas Culina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Prognóstico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Taxa de Sobrevida , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
3.
Breast Cancer Res Treat ; 189(2): 347-361, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34240274

RESUMO

PURPOSE: Epigenetic regulation plays critical roles in cancer progression, and high-frequency mutations or expression variations in epigenetic regulators have been frequently observed in tumorigenesis, serving as biomarkers and targets for cancer therapy. Here, we aimed to explore the function of epigenetic regulators in breast cancer. METHODS: The mutational landscape of epigenetic regulators in breast cancer samples was investigated based on datasets from the Cancer Genome Atlas. The Kaplan-Meier method was used for survival analysis. RNA sequencing (RNA-seq) in MCF-7 cells transfected with control siRNA or KMT2C siRNA was performed. Quantitative reverse transcription-PCR and chromatin immunoprecipitation were used to validate the RNA-seq results. RESULTS: Among the 450 epigenetic regulators, KMT2C was frequently mutated in breast cancer samples. The tumor mutational burden (TMB) was elevated in breast cancer samples with KMT2C mutations or low KMT2C mRNA levels compared to their counterparts with wild-type KMT2C or high KMT2C mRNA levels. Somatic mutation and low expression of KMT2C were independently correlated with the poor overall survival (OS) and disease-free survival (DFS) of the breast cancer samples, respectively. RNA-seq analysis combined with chromatin immunoprecipitation and qRT-PCR assays revealed that the depletion of KMT2C remarkably affected the expression of DNA damage repair-related genes. More importantly, the low expression of KMT2C was related to breast cancer cell sensitivity to chemotherapy and longer OS of breast cancer patients who underwent chemotherapy. CONCLUSION: We conclude that KMT2C could serve as a potential biomarker of prognosis and chemotherapy sensitivity by affecting the DNA damage repair-related genes of breast cancer.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Epigênese Genética , Feminino , Humanos , Mutação , Prognóstico
4.
Free Radic Biol Med ; 172: 312-329, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34144192

RESUMO

INTRODUCTION: Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a group of chronic recurrent and incurable gastrointestinal diseases with an unknown etiology that leads to a high risk of developing colitis-associated colorectal cancer (CRC). OBJECTIVES: In this study, we measured the expression characteristics of MELK in IBD and CRC tissues and explored the regulatory effect of OTSSP167 (a MELK-selective inhibitor) on the mice models of colitis and colitis-associated carcinogenesis and analyzed the specific molecular mechanisms. METHODS: DSS-induced colitis and colitis-associated carcinogenesis (CAC) model were treated with MELK inhibitor OTSSP167 then the fight against effect of OTSSP167 in the clinical symptoms of colitis and CAC was measured. In addition, underlying mechanism of OTSSP167 treatment in vitro and vivo including anti-ferroptosis and anti-inflammatory response effect was further explored. RESULTS: We found that pharmacological inhibition of MELK was indicated to significantly alleviate the inflammatory response in mice with colitis, reduce intestinal damage, and effectively inhibit the occurrence and progression of colitis-propelled carcinogenesis, which was closely related to the regulation of gut microbial composition, and OTSSP167-mediated fecal microbiota transplantation effectively alleviated DSS-induced colitis. In addition, OTSSP167 treatment obviously inhibited ferroptosis in the intestinal tissue and suppressed macrophage infiltration and M1 polarization, which reduced the secretion of pro-inflammatory factors. Further exploration of the molecular mechanism revealed that OTSSP167 inhibited AKT/IKK/P65 and ERK/IKK/P65 signaling cascades both in vivo and in vitro, which may help alleviate intestinal inflammation and control the occurrence of cancer. CONCLUSION: Our findings lay a theoretical foundation for the use of OTSSP167 as a treatment for IBD and its inhibition of the occurrence of colitis-associated carcinogenesis; additionally, MELK may be a potentially effective target molecule, thus providing more options for clinical treatment.


Assuntos
Colite , Ferroptose , Animais , Carcinogênese , Colite/induzido quimicamente , Colite/complicações , Colite/tratamento farmacológico , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
5.
J Biomed Sci ; 28(1): 44, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112167

RESUMO

BACKGROUND: Cholangiocarcinoma represents the second most common primary liver malignancy. The incidence rate has constantly increased over the last decades. Cholangiocarcinoma silent nature limits early diagnosis and prevents efficient treatment. METHODS: Immunoblotting and immunohistochemistry were used to assess the expression profiling of USP9X and EGLN3 in cholangiocarcinoma patients. ShRNA was used to silence gene expression. Cell apoptosis, cell cycle, CCK8, clone formation, shRNA interference and xenograft mouse model were used to explore biological function of USP9X and EGLN3. The underlying molecular mechanism of USP9X in cholangiocarcinoma was determined by immunoblotting, co-immunoprecipitation and quantitative real time PCR (qPCR). RESULTS: Here we demonstrated that USP9X is downregulated in cholangiocarcinoma which contributes to tumorigenesis. The expression of USP9X in cholangiocarcinoma inhibited cell proliferation and colony formation in vitro as well as xenograft tumorigenicity in vivo. Clinical data demonstrated that expression levels of USP9X were positively correlated with favorable clinical outcomes. Mechanistic investigations further indicated that USP9X was involved in the deubiquitination of EGLN3, a member of 2-oxoglutarate and iron-dependent dioxygenases. USP9X elicited tumor suppressor role by preventing degradation of EGLN3. Importantly, knockdown of EGLN3 impaired USP9X-mediated suppression of proliferation. USP9X positively regulated the expression level of apoptosis pathway genes de through EGLN3 thus involved in apoptosis of cholangiocarcinoma. CONCLUSION: These findings help to understand that USP9X alleviates the malignant potential of cholangiocarcinoma through upregulation of EGLN3. Consequently, we provide novel insight into that USP9X is a potential biomarker or serves as a therapeutic or diagnostic target for cholangiocarcinoma.


Assuntos
Apoptose/genética , Colangiocarcinoma/fisiopatologia , Regulação Neoplásica da Expressão Gênica , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Cinesina/genética , Ubiquitina Tiolesterase/genética , Animais , Colangiocarcinoma/genética , Feminino , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Cinesina/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ubiquitina Tiolesterase/metabolismo , Ubiquitinação
6.
Front Immunol ; 11: 592084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240279

RESUMO

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is a group of chronic and incurable inflammatory diseases involving the gastrointestinal tract. In this study, we investigated the anti-inflammatory effects of triptolide in a dextran sulfate sodium (DSS)-induced mouse colitis model and LPS-activated macrophages and explored the specific molecular mechanism(s). In mice, triptolide treatment showed significant relief and protection against colitis, and it markedly reduced the inflammatory responses of human monocytes and mouse macrophages. Pharmacological analysis and weighted gene co-expression network analysis (WGCNA) suggested that PDE4B may be an important potential targeting molecule for IBD. Exploration of the specific mechanism of action indicated that triptolide reduced the production of ROS, inhibited macrophage infiltration and M1-type polarization by activating the NRF2/HO-1 signaling pathway, and inhibited the PDE4B/AKT/NF-κB signaling cascade, which may help weaken the intestinal inflammatory response. Our findings laid a theoretical foundation for triptolide as a treatment for IBD and revealed PDE4B as a target molecule, thus providing new ideas for the treatment of IBD.


Assuntos
Anti-Inflamatórios/farmacologia , Colite/tratamento farmacológico , Diterpenos/farmacologia , Fenantrenos/farmacologia , Animais , Anti-Inflamatórios/química , Biomarcadores , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Biologia Computacional/métodos , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Diterpenos/química , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Perfilação da Expressão Gênica , Mediadores da Inflamação/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Lipopolissacarídeos/imunologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Modelos Biológicos , Fenantrenos/química , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Sci Adv ; 6(16): eaaz0356, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32494608

RESUMO

TUDOR domain-containing proteins (TDRDs) are chiefly responsible for recognizing methyl-lysine/arginine residue. However, how TDRD dysregulation contributes to breast tumorigenesis is poorly understood. Here, we report that TUDOR domain-containing PHF20L1 as a H3K27me2 reader exerts transcriptional repression by recruiting polycomb repressive complex 2 (PRC2) and Mi-2/nucleosome remodeling and deacetylase (NuRD) complex, linking PRC2-mediated methylation and NuRD-mediated deacetylation of H3K27. Furthermore, PHF20L1 was found to serve as a potential MYC and hypoxia-driven oncogene, promoting glycolysis, proliferation, and metastasis of breast cancer cells by directly inhibiting tumor suppressors such as HIC1, KISS1, and BRCA1. PHF20L1 expression was also strongly correlated with higher histologic grades of breast cancer and markedly up-regulated in several cancers. Meanwhile, Phf20l1 deletion not only induces growth retardation and mammary ductal outgrowth delay but also inhibits tumorigenesis in vivo. Our data indicate that PHF20L1 promotes tumorigenesis, supporting the pursuit of PHF20L1 as a target for cancer therapy.

8.
Cell Death Dis ; 10(11): 832, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685800

RESUMO

GATA3 has emerged as a prominent transcription factor required for maintaining mammary-gland homeostasis. GATA3 loss is associated with aggressive breast cancer development, but the mechanism by which breast cancer is affected by the loss of GATA3 function remains unclear. Here, we report that GATA3 expression is positively correlated with the expression of UTX, a histone H3K27 demethylase contained in the MLL4 methyltransferase complex, and that GATA3 recruits the chromatin-remodeling MLL4 complex and interacts directly with UTX, ASH2L, and RBBP5. Using RNA sequencing and chromatin immunoprecipitation and sequencing, we demonstrate that the GATA3/UTX complex synergistically regulates a cohort of genes including Dicer and UTX, which are critically involved in the epithelial-to-mesenchymal transition (EMT). Our results further show that the GATA3-UTX-Dicer axis inhibits EMT, invasion, and metastasis of breast cancer cells in vitro and the dissemination of breast cancer in vivo. Our study implicates the GATA3-UTX-Dicer axis in breast cancer metastasis and provides new mechanistic insights into the pathophysiological function of GATA3.


Assuntos
Neoplasias da Mama/metabolismo , Fator de Transcrição GATA3/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/biossíntese , Proteínas de Neoplasias/metabolismo , Ativação Transcricional , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Fator de Transcrição GATA3/genética , Histona Desmetilases/genética , Humanos , Células MCF-7 , Metástase Neoplásica , Proteínas de Neoplasias/genética
9.
Cell Rep ; 29(6): 1482-1498.e4, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31693890

RESUMO

The histone methyl transferase enhancer of zeste homolog 2 (EZH2) is a master transcriptional regulator involved in histone H3 lysine 27 trimethylation. We aimed to elucidate the precise post-translational regulations of EZH2 and their role in cancer pathogenesis. Here, we show that SET and MYND domain containing 2 (SMYD2) directly methylates EZH2 at lysine 307 (K307) and enhances its stability, which can be relieved by the histone H3K4 demethylase lysine-specific demethylase 1 (LSD1). SMYD2 is critical for EZH2 function in repressing a cohort of genes governing several cancer-associated pathways. In addition, SMYD2 promotes breast cancer cell proliferation, epithelial-mesenchymal transition, and invasion through EZH2 K307 methylation, and it is markedly upregulated in various human cancers. Our data suggest that dynamic crosstalk between SMYD2-mediated EZH2 methylation plays an important role in fine-tuning EZH2 functions in chromatin recruitment and transcriptional repression.


Assuntos
Neoplasias da Mama/metabolismo , Carcinogênese/genética , Cromatina/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Lisina/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Cromatina/genética , Imunoprecipitação da Cromatina , Bases de Dados Genéticas , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Histona-Lisina N-Metiltransferase/genética , Humanos , Metilação , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Processamento de Proteína Pós-Traducional
10.
J Biol Chem ; 294(43): 15808-15825, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31492753

RESUMO

GATA3 is a basic and essential transcription factor that regulates many pathophysiological processes and is required for the development of mammary luminal epithelial cells. Loss-of-function GATA3 alterations in breast cancer are associated with poor prognosis. Here, we sought to understand the tumor-suppressive functions GATA3 normally performs. We discovered a role for GATA3 in suppressing epithelial-to-mesenchymal transition (EMT) in breast cancer by activating miR-455-3p expression. Enforced expression of miR-455-3p alone partially prevented EMT induced by transforming growth factor ß (TGF-ß) both in cells and tumor xenografts by directly inhibiting key components of TGF-ß signaling. Pathway and biochemical analyses showed that one miRNA-455-3p target, the TGF-ß-induced protein ZEB1, recruits the Mi-2/nucleosome remodeling and deacetylase (NuRD) complex to the promotor region of miR-455 to strictly repress the GATA3-induced transcription of this microRNA. Considering that ZEB1 enhances TGF-ß signaling, we delineated a double-feedback interaction between ZEB1 and miR-455-3p, in addition to the repressive effect of miR-455-3p on TGF-ß signaling. Our study revealed that a feedback loop between these two axes, specifically GATA3-induced miR-455-3p expression, could repress ZEB1 and its recruitment of NuRD (MTA1) to suppress miR-455, which ultimately regulates TGF-ß signaling. In conclusion, we identified that miR-455-3p plays a pivotal role in inhibiting the EMT and TGF-ß signaling pathway and maintaining cell differentiation. This forms the basis of that miR-455-3p might be a promising therapeutic intervention for breast cancer.


Assuntos
Células Epiteliais/metabolismo , Fator de Transcrição GATA3/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Animais , Sequência de Bases , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Camundongos SCID , MicroRNAs/genética , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Transcrição Genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
11.
Am J Cancer Res ; 8(10): 2030-2045, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416854

RESUMO

Breast carcinoma metastasis suppressor gene 1 (BRMS1) encodes an inhibitor of metastasis and is reported in many types of tumor metastasis. However, the mechanism of BRMS1-mediated inhibition of breast cancer metastasis at the transcriptional level remains elusive. Here, we identified using affinity purification and mass spectrometry (MS) that BRMS1 is an integral component of the LSD1/CoREST corepressor complex. Analysis of the BRMS1/LSD1 complex using high-throughput RNA deep sequencing (RNA-seq) identified a cohort of target genes such as VIM, INSIG2, KLK11, MRPL33, COL5A2, OLFML3 and SLC1A1, some of which are metastasis-related. Our results have showed that BRMS1 together with LSD1 are required for inhibition of breast cancer cell migration and invasion. Collectively, these findings demonstrate that BRMS1 executes transcriptional suppression of breast cancer metastasis by associating with the LSD1 and thus can be targeted for breast cancer therapy.

12.
Carcinogenesis ; 39(10): 1222-1234, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30052810

RESUMO

The role of O-GlcNAc transferase (OGT) in gene regulation and tumor invasion is poorly understood. Here, we have identified several previously undiscovered OGT-interacting proteins, including the PRMT5/WDR77 complex, the PRC2 complex, the ten-eleven translocation (TET) family, the CRL4B complex and the nucleosome remodeling and deacetylase (NuRD) complex. Genome-wide analysis of target genes responsive to OGT resulted in identification of a cohort of genes including SNAI1 and ING4 that are critically involved in cell epithelial-mesenchymal transition and invasion/metastasis. We have demonstrated that OGT promotes carcinogenesis and metastasis of cervical cancer cells. OGT's expression is significantly upregulated in cervical cancer, and low OGT level is correlated with improved prognosis. Our study has thus revealed a mechanistic link between OGT and tumor progression, providing potential prognostic indicators and targets for cancer therapy.


Assuntos
Carcinogênese/genética , Transição Epitelial-Mesenquimal/genética , N-Acetilglucosaminiltransferases/metabolismo , Neoplasias do Colo do Útero/metabolismo , Western Blotting , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imunoprecipitação , Espectrometria de Massas , Proteômica/métodos , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
13.
J Mol Cell Biol ; 10(4): 285-301, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29741645

RESUMO

Lysine-specific demethylase 1 (LSD1) was the first histone demethylase identified as catalysing the removal of mono- and di-methylation marks on histone H3-K4. Despite the potential broad action of LSD1 in transcription regulation, recent studies indicate that LSD1 may coordinate with multiple epigenetic regulatory complexes including CoREST/HDAC complex, NuRD complex, SIRT1, and PRC2, implying complicated mechanistic actions of this seemingly simple enzyme. Here, we report that LSD1 is also an integral component of the SIN3A/HDAC complex. Transcriptional target analysis using ChIP-on-chip technology revealed that the LSD1/SIN3A/HDAC complex targets several cellular signalling pathways that are critically involved in cell proliferation, survival, metastasis, and apoptosis, especially the p53 signalling pathway. We have demonstrated that LSD1 coordinates with the SIN3A/HDAC complex in inhibiting a series of genes such as CASP7, TGFB2, CDKN1A(p21), HIF1A, TERT, and MDM2, some of which are oncogenic. Our experiments also found that LSD1 and SIN3A are required for optimal survival and growth of breast cancer cells while also essential for the maintenance of epithelial homoeostasis and chemosensitivity. Our data indicate that LSD1 is a functional alternative subunit of the SIN3A/HDAC complex, providing a molecular basis for the interplay of histone demethylation and deacetylation in chromatin remodelling, and suggest that the LSD1/SIN3A/HDAC complex could be a target for breast cancer therapeutic strategies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Histona Desacetilases/metabolismo , Histona Desmetilases/metabolismo , Mapas de Interação de Proteínas , Proteínas Repressoras/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Mapas de Interação de Proteínas/efeitos dos fármacos , Complexo Correpressor Histona Desacetilase e Sin3
14.
Nucleic Acids Res ; 46(13): 6608-6626, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-29846670

RESUMO

Histone post-translational modifications regulate chromatin structure and function largely through interactions with effector proteins that often contain multiple histone-binding domains. PHF1 [plant homeodomain (PHD) finger protein 1], which contains two kinds of histone reader modules, a Tudor domain and two PHD fingers, is an essential factor for epigenetic regulation and genome maintenance. While significant progress has been made in characterizing the function of the Tudor domain, the roles of the two PHD fingers are poorly defined. Here, we demonstrated that the N-terminal PHD finger of PHF1 recognizes symmetric dimethylation of H4R3 (H4R3me2s) catalyzed by PRMT5-WDR77. However, the C-terminal PHD finger of PHF1, instead of binding to modified histones, directly interacts with DDB1, the main component of the CUL4B-Ring E3 ligase complex (CRL4B), which is responsible for H2AK119 mono-ubiquitination (H2AK119ub1). We showed that PHF1, PRMT5-WDR77, and CRL4B reciprocally interact with one another and collaborate as a functional unit. Genome-wide analysis of PHF1/PRMT5/CUL4B targets identified a cohort of genes including E-cadherin and FBXW7, which are critically involved in cell growth and migration. We demonstrated that PHF1 promotes cell proliferation, invasion, and tumorigenesis in vivo and in vitro and found that its expression is markedly upregulated in a variety of human cancers. Our data identified a new reader for H4R3me2s and provided a molecular basis for the functional interplay between histone arginine methylation and ubiquitination. The results also indicated that PHF1 is a key factor in cancer progression, supporting the pursuit of PHF1 as a target for cancer therapy.


Assuntos
Carcinogênese , Proteínas de Ligação a DNA/metabolismo , Histonas/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/genética , Caderinas/metabolismo , Carcinoma/metabolismo , Linhagem Celular , Proliferação de Células , Proteínas Culina/metabolismo , Proteínas de Ligação a DNA/fisiologia , Proteína 7 com Repetições F-Box-WD/genética , Proteína 7 com Repetições F-Box-WD/metabolismo , Feminino , Células HEK293 , Humanos , Metilação , Camundongos , Metástase Neoplásica , Proteínas do Grupo Polycomb/fisiologia , Proteína-Arginina N-Metiltransferases/química , Proteína-Arginina N-Metiltransferases/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética
15.
Theranostics ; 8(4): 972-989, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29463994

RESUMO

The homeodomain transcription factor SIX3 was recently reported to be a negative regulator of the Wnt pathway and has an emerging role in cancer. However, how SIX3 contributes to tumorigenesis and metastasis is poorly understood. METHODS: We employed affinity purification and mass spectrometry (MS) to identify the proteins physically associated with SIX3. Genome-wide analysis of the SIX3/LSD1/NuRD(MTA3) complex using a chromatin immunoprecipitation-on-chip approach identified a cohort of target genes including WNT1 and FOXC2, which are critically involved in cell proliferation and epithelial-to-mesenchymal transition. Also, we used flow cytometry, growth curve analysis, EdU incorporation assay, colony formation assays, trans-well invasion assays, immunohistochemical staining and in vivo bioluminescence assay to investigate the function of SIX3 in tumorigenesis. RESULTS: We demonstrate that the SIX3/LSD1/NuRD(MTA3) complex inhibits carcinogenesis in breast cancer cells and suppresses metastasis in breast cancer. SIX3 expression is downregulated in various human cancers and high SIX3 is correlated with improved prognosis. CONCLUSION: Our study revealed an important mechanistic link between the loss of function of SIX3 and tumor progression, identified a molecular basis for the opposing actions of MTA1 and MTA3, and may provide new potential prognostic indicators and targets for cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Carcinogênese , Proteínas do Olho/metabolismo , Histona Desmetilases/metabolismo , Proteínas de Homeodomínio/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Metástase Neoplásica/fisiopatologia , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Linhagem Celular Tumoral , Cromatografia de Afinidade , Técnicas Citológicas , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Imunoprecipitação , Espectrometria de Massas , Modelos Biológicos , Ligação Proteica , Ensaio Tumoral de Célula-Tronco
16.
J Immunol ; 198(7): 2626-2639, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28228555

RESUMO

IL-17-producing Th17 cells have gradually become considered as key factors in the pathogenesis of many autoimmune diseases, including multiple sclerosis (MS). Although the involvement of certain microRNAs in the development of MS has been reported, their role in Th17-driven autoimmunity is still poorly understood. In this study, we identified microRNA (miR)-15b as an important factor in Th17-associated effects and determined that the expression of miR-15b is significantly downregulated in MS patients and in mice with experimental autoimmune encephalomyelitis. Overexpression of miR-15b alleviated experimental autoimmune encephalomyelitis, whereas knockdown of miR-15b aggravated it. We demonstrated that miR-15b suppressed Th17 differentiation both in vivo and in vitro. We also found that O-linked N-acetylglucosamine transferase is a potential target of miR-15b, enabling it to affect the transcriptional regulation of retinoic acid-related orphan receptor γT through O-linked N-acetylglucosamine glycosylation of NF-κB. These results contribute to the importance of miR-15b in Th17 differentiation and the pathogenesis of MS.


Assuntos
Regulação da Expressão Gênica/imunologia , MicroRNAs/imunologia , Esclerose Múltipla/imunologia , N-Acetilglucosaminiltransferases/biossíntese , Células Th17/imunologia , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Separação Celular , Regulação para Baixo , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Esclerose Múltipla/genética , N-Acetilglucosaminiltransferases/imunologia , Reação em Cadeia da Polimerase em Tempo Real
17.
Sci Rep ; 5: 17194, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26603569

RESUMO

ORMDL sphingolipid biosynthesis regulator 3 (ORMDL3) is a universally confirmed susceptibility gene for asthma and has recently emerged as a crucial modulator in lipid metabolism, inflammation and endoplasmic reticulum (ER) stress-the mechanisms also closely involved in atherosclerosis (AS). Here we first presented the evidence of two single nucleotide polymorphisms regulating ORMDL3 expression (rs7216389 and rs9303277) significantly associated with AS risk and the evidence of increased ORMDL3 expression in AS cases compared to controls, in Chinese Han population. Following the detection of its statistical correlation with AS, we further explored the functional relevance of ORMDL3 and hypothesized a potential role mediating autophagy as autophagy is activated upon modified lipid, inflammation and ER stress. Our results demonstrated that in endothelial cells oxidized low-density lipoprotein (ox-LDL) up-regulated ORMDL3 expression and knockdown of ORMDL3 alleviated not only ox-LDL-induced but also basal autophagy. BECN1 is essential for autophagy initiation and silencing of ORMDL3 suppressed ox-LDL-induced as well as basal BECN1 expression. In addition, deletion of ORMDL3 resulted in greater sensitivity to ox-LDL-induced cell death. Taken together, ORMDL3 might represent a causal gene mediating autophagy in endothelial cells in the pathogenesis of AS.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Aterosclerose/patologia , Lipoproteínas LDL/toxicidade , Proteínas de Membrana/metabolismo , Idoso , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Autofagia/efeitos dos fármacos , Proteína Beclina-1 , Estudos de Casos e Controles , China , Estudos de Coortes , Estresse do Retículo Endoplasmático , Feminino , Genótipo , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Interferência de RNA , Fatores de Risco , Regulação para Cima/efeitos dos fármacos
18.
Eur J Hum Genet ; 22(9): 1105-10, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24496061

RESUMO

Split-hand/foot malformation (SHFM) is a congenital limb deformity due to the absence or dysplasia of central rays of the autopod. Six SHFM loci have already been identified. Here we describe a Chinese family with autosomal-dominant SHFM1 that has previously been mapped to 7q21.2-21.3. The two affected family members, mother and son, showed deep median clefts between toes, ectrodactyly and syndactyly; the mother also showed triphalangeal thumbs. Exome sequencing and variant screening of candidate genes in the six loci known to be responsible for SHFM revealed a novel heterozygous mutation, c.558G>T (p.(Gln186His)), in distal-less homeobox 5 (DLX5). As DLX5 encodes a transcription factor capable of transactivating MYC, we also tested whether the mutation could affect DLX5 transcription acitivity. Results from luciferase reporter assay revealed that a mutation in DLX5 compromised its transcriptional activity. This is the first report of a mutation in DLX5 leading to autosomal-dominant SHFM1.


Assuntos
Exoma , Deformidades Congênitas do Pé/genética , Deformidades Congênitas da Mão/genética , Perda Auditiva Neurossensorial/genética , Heterozigoto , Proteínas de Homeodomínio/genética , Mutação de Sentido Incorreto , Linhagem , Fatores de Transcrição/genética , Adulto , Sequência de Aminoácidos , Criança , Feminino , Deformidades Congênitas do Pé/diagnóstico , Genes Dominantes , Células HEK293 , Deformidades Congênitas da Mão/diagnóstico , Células HeLa , Perda Auditiva Neurossensorial/diagnóstico , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , Fatores de Transcrição/metabolismo
19.
J Rheumatol ; 41(2): 318-24, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24334645

RESUMO

OBJECTIVE: A genome-wide association study and 2 replication studies identified 2 single-nucleotide polymorphisms (SNP) of caspase recruitment domain-containing protein 9 (CARD9) and small nuclear RNA-activating complex polypeptide 4 (SNAPC4) at Chr 9q34.3 associated with ankylosing spondylitis (AS) in whites. We explored a possible association of SNP in CARD9 and SNAPC4 and AS in a Chinese Han population from Shandong. METHODS: The study included 1150 patients with AS and 1120 healthy controls who underwent genotyping for 4 SNP of CARD9 and 2 of SNAPC4; we replicated the results in another 490 patients and 380 healthy controls of Ningxia Han Chinese during the same time. We used quantitative real-time PCR (qRT-PCR) to measure CARD9 and SNAPC4 mRNA expression in peripheral leukocytes from 44 patients and 36 controls and allele-specific mRNA expression of CARD9 and SNAPC4 in leukocytes from 130 controls. RESULTS: We validated that an SNP in SNAPC4, rs11145835, was significantly associated with AS in our Chinese Han population (p = 0.001) and replicated the association in samples from the Chinese Ningxia Han population (p = 0.002). Carrying the G allele of rs11145835 was associated with increased risk of AS (OR 1.34, 95% CI 1.12-1.59) and with decreased expression of CARD9 (p = 0.001) and SNAPC4 (p = 0.02) in leukocytes. SNAPC4 mRNA expression was lower in leukocytes from patients than from controls (p = 0.0002). CONCLUSION: Our study confirmed that an SNP rs11145835 in 9q34.3 that harbors CARD9 and SNAPC4 is associated with AS in a Chinese Han population, and rs11145835 in SNAPC4 is a potential causal variant.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas de Ligação a DNA/genética , Genótipo , Polimorfismo de Nucleotídeo Único , Espondilite Anquilosante/genética , Fatores de Transcrição/genética , Adulto , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(4): 477-80, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23926020

RESUMO

OBJECTIVE: To assess the association between 2 single nucleotide polymorphisms (SNPs) of ETS1 gene and susceptibility to systemic lupus erythematosus (SLE) in a northern Chinese Han population. METHODS: Two SNPs within the ETS1 gene mapped to 11q23 were selected based on HapMap data. Genotyping was conducted with Taqman method in 231 patients with SLE and 474 healthy controls from Qilu Hospital, Shandong and analyzed with PLINK1.07 software. Haplotypes were analyzed with SHEsis software. RESULTS: A statistically significant difference was detected in the distribution of rs1128334 and rs4937333 genotypes between the two groups (all P< 0.01). For rs1128334, the frequency of the minor allele was 0.291 and 0.428 in controls and cases, respectively. For rs4937333, the minor allele frequency was 0.381 and 0.476 in controls and cases respectively. An A-C haplotype was found to be strongly associated with increased risk for SLE, while another haplotype G-C may reduce this risk. CONCLUSION: Our study has suggested that rs1128334 and rs4937333 are strongly associated with the risk for SLE in northern Chinese Han population.


Assuntos
Regiões 3' não Traduzidas , Grupo com Ancestrais do Continente Asiático/genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único , Proteína Proto-Oncogênica c-ets-1/genética , Adolescente , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático/etnologia , Feminino , Estudos de Associação Genética , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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