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1.
Carcinogenesis ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446998

RESUMO

Cysteine-rich angiogenic inducer 61 (CYR61) is a protein from the CCN family of matricellular proteins that play diverse regulatory roles in the extracellular matrix. CYR61 is involved in cell adhesion, migration, proliferation, differentiation, apoptosis, and senescence. Here, we show that CYR61 induces chemoresistance in triple-negative breast cancer (TNBC). We observed that CYR61 is overexpressed in TNBC patients, and CYR61 expression correlates negatively with the survival of patients who receive chemotherapy. CYR61 knockdown reduced cell migration, sphere formation, and the cancer stem cell (CSC) population and increased the chemosensitivity of TNBC cells. Mechanistically, CYR61 activated Wnt/ß-catenin signaling and increased survivin expression, which are associated with chemoresistance, the epithelial-mesenchymal transition, and CSC-like phenotypes. Altogether, our study demonstrates a novel function of CYR61 in chemotherapy resistance in breast cancer.

2.
Cell Commun Signal ; 22(1): 190, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521953

RESUMO

BACKGROUND: Solid tumors promote tumor malignancy through interaction with the tumor microenvironment, resulting in difficulties in tumor treatment. Therefore, it is necessary to understand the communication between cells in the tumor and the surrounding microenvironment. Our previous study revealed the cancer malignancy mechanism of Bcl-w overexpressed in solid tumors, but no study was conducted on its relationship with immune cells in the tumor microenvironment. In this study, we sought to discover key factors in exosomes secreted from tumors overexpressing Bcl-w and analyze the interaction with the surrounding tumor microenvironment to identify the causes of tumor malignancy. METHODS: To analyze factors affecting the tumor microenvironment, a miRNA array was performed using exosomes derived from cancer cells overexpressing Bcl-w. The discovered miRNA, miR-6794-5p, was overexpressed and the tumorigenicity mechanism was confirmed using qRT-PCR, Western blot, invasion, wound healing, and sphere formation ability analysis. In addition, luciferase activity and Ago2-RNA immunoprecipitation assays were used to study the mechanism between miR-6794-5p and its target gene SOCS1. To confirm the interaction between macrophages and tumor-derived miR-6794-5p, co-culture was performed using conditioned media. Additionally, immunohistochemical (IHC) staining and flow cytometry were performed to analyze macrophages in the tumor tissues of experimental animals. RESULTS: MiR-6794-5p, which is highly expressed in exosomes secreted from Bcl-w-overexpressing cells, was selected, and it was shown that the overexpression of miR-6794-5p increased migratory ability, invasiveness, and stemness maintenance by suppressing the expression of the tumor suppressor SOCS1. Additionally, tumor-derived miR-6794-5p was delivered to THP-1-derived macrophages and induced M2 polarization by activating the JAK1/STAT3 pathway. Moreover, IL-10 secreted from M2 macrophages increased tumorigenicity by creating an immunosuppressive environment. The in vitro results were reconfirmed by confirming an increase in M2 macrophages and a decrease in M1 macrophages and CD8+ T cells when overexpressing miR-6794-5p in an animal model. CONCLUSIONS: In this study, we identified changes in the tumor microenvironment caused by miR-6794-5p. Our study indicates that tumor-derived miR-6794-5p promotes tumor aggressiveness by inducing an immunosuppressive environment through interaction with macrophage.


Assuntos
Exossomos , MicroRNAs , Neoplasias , Animais , Neoplasias/genética , Bioensaio , Transporte Biológico , Linfócitos T CD8-Positivos , MicroRNAs/genética , Microambiente Tumoral
3.
BMC Bioinformatics ; 24(1): 447, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012571

RESUMO

BACKGROUND: Aptamers, which are biomaterials comprised of single-stranded DNA/RNA that form tertiary structures, have significant potential as next-generation materials, particularly for drug discovery. The systematic evolution of ligands by exponential enrichment (SELEX) method is a critical in vitro technique employed to identify aptamers that bind specifically to target proteins. While advanced SELEX-based methods such as Cell- and HT-SELEX are available, they often encounter issues such as extended time consumption and suboptimal accuracy. Several In silico aptamer discovery methods have been proposed to address these challenges. These methods are specifically designed to predict aptamer-protein interaction (API) using benchmark datasets. However, these methods often fail to consider the physicochemical interactions between aptamers and proteins within tertiary structures. RESULTS: In this study, we propose AptaTrans, a pipeline for predicting API using deep learning techniques. AptaTrans uses transformer-based encoders to handle aptamer and protein sequences at the monomer level. Furthermore, pretrained encoders are utilized for the structural representation. After validation with a benchmark dataset, AptaTrans has been integrated into a comprehensive toolset. This pipeline synergistically combines with Apta-MCTS, a generative algorithm for recommending aptamer candidates. CONCLUSION: The results show that AptaTrans outperforms existing models for predicting API, and the efficacy of the AptaTrans pipeline has been confirmed through various experimental tools. We expect AptaTrans will enhance the cost-effectiveness and efficiency of SELEX in drug discovery. The source code and benchmark dataset for AptaTrans are available at https://github.com/pnumlb/AptaTrans .


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/química , Técnica de Seleção de Aptâmeros/métodos , Software , Redes Neurais de Computação , Algoritmos , Ligantes
4.
J Cell Sci ; 134(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34096606

RESUMO

About 70% of breast cancers overexpress estrogen receptor α (ERα, encoded by ESR1). Tamoxifen, a competitive inhibitor of estrogen that binds to ER, has been widely used as a treatment for ER-positive breast cancer. However, 20-30% of breast cancer is resistant to tamoxifen treatment. The mechanisms underlying tamoxifen resistance remain elusive. We found that Yes-associated protein (YAP; also known as YAP1), connective tissue growth factor (CTGF; also known as CCN2) and cysteine-rich angiogenic inducer 61 (Cyr61; also known as CCN1) are overexpressed, while ERα is downregulated in tamoxifen-resistant breast cancer. Inhibition of YAP, CTGF and Cyr61 restored ERα expression and increased sensitivity to tamoxifen. Overexpression of YAP, CTGF, and Cyr61 led to downregulation of ERα and conferred resistance to tamoxifen in ER-positive breast cancer cells. Mechanistically, CTGF and Cyr61 downregulated ERα expression at the transcriptional level by directly binding to the regulatory regions of the ERα-encoding gene, leading to increased tamoxifen resistance. Also, CTGF induced Glut3 (also known as SLC2A3) expression, leading to increased glycolysis, which enhanced cell proliferation and migration in tamoxifen-resistant cells. Together, these results demonstrate a novel role of YAP, CTGF and Cyr61 in tamoxifen resistance and provide a molecular basis for their function in tamoxifen-resistant breast cancer.


Assuntos
Neoplasias da Mama , Tamoxifeno , Proteínas Adaptadoras de Transdução de Sinal , Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/genética , Proteína Rica em Cisteína 61 , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Tamoxifeno/farmacologia , Fatores de Transcrição , Proteínas de Sinalização YAP
5.
Adv Exp Med Biol ; 1187: 53-79, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983573

RESUMO

HER2 gene amplification occurs in many breast cancer patients and is associated with poor clinical prognosis. Trastuzumab is a therapeutic monoclonal antibody binding to HER2 and inhibits growth of HER2-positive breast cancer cells and used as a principal treatment for HER2-positive breast cancer. Unfortunately, some HER2-positive breast cancers eventually relapse after trastuzumab treatment. To investigate the molecular mechanism of trastuzumab resistance, we generated trastuzumab-resistant cells using a mouse model and found ECM1 protein is increased in trastuzumab-resistant cells. ECM1 was shown to increase EGFR signaling via upregulated matrix metalloproteinase 9/galectin-3/mucin pathway. To further find the novel mediators of HER2-driven signaling pathways in breast cancer, we investigated the upregulated proteins in HER2-overexpressing breast cancer cells using a proteomics approach and found that KRT19 is strongly upregulated in HER2-positive breast cancer cells and it activates HER2 signaling by binding to HER2 and stabilizes the receptor on the cell membrane. Moreover, we found that treatment of KRT19 antibody resulted in reduced cell viability of trastuzumab-resistant HER2-positive breast cancer cells as well as trastuzumab-sensitive cancer cells both in vitro and in vivo.


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas da Matriz Extracelular/uso terapêutico , Humanos , Recidiva Local de Neoplasia , Receptor ErbB-2/genética , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico
6.
Small ; 16(21): e1907674, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32163679

RESUMO

Understanding the interactions between nanoparticles (NPs) and human immune cells is necessary for justifying their utilization in consumer products and biomedical applications. However, conventional assays may be insufficient in describing the complexity and heterogeneity of cell-NP interactions. Herein, mass cytometry and single-cell RNA-sequencing (scRNA-seq) are complementarily used to investigate the heterogeneous interactions between silver nanoparticles (AgNPs) and primary immune cells. Mass cytometry reveals the heterogeneous biodistribution of the positively charged polyethylenimine-coated AgNPs in various cell types and finds that monocytes and B cells have higher association with the AgNPs than other populations. scRNA-seq data of these two cell types demonstrate that each type has distinct responses to AgNP treatment: NRF2-mediated oxidative stress is confined to B cells, whereas monocytes show Fcγ-mediated phagocytosis. Besides the between-population heterogeneity, analysis of single-cell dose-response relationships further reveals within-population diversity for the B cells and naïve CD4+ T cells. Distinct subsets having different levels of cellular responses with respect to their cellular AgNP doses are found. This study demonstrates that the complementary use of mass cytometry and scRNA-seq is helpful for gaining in-depth knowledge on the heterogeneous interactions between immune cells and NPs and can be incorporated into future toxicity assessments of nanomaterials.


Assuntos
Leucócitos Mononucleares , Nanopartículas Metálicas , Prata , Linfócitos B/efeitos dos fármacos , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , RNA-Seq , Prata/química , Prata/toxicidade , Análise de Célula Única , Distribuição Tecidual
8.
Environ Res ; 175: 117-123, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31112848

RESUMO

Titanium dioxide nanoparticles, due to their smaller size and increased surface area comparted to the bulk form, are known to be bioreactive and have unexpected toxicological outcomes. Previous studies have shown that nanoscale titanium dioxide induces reactive oxygen species (ROS)-mediated cytotoxicity and genotoxicity. Although many reports have discussed the ROS-mediated cytotoxic effects of titanium dioxide nanoparticles (TiO2-NPs), their effects on the receptor-ligand association are unknown. In this study, the possibility that TiO2-NPs can interfere with the receptor-ligand binding was assessed by monitoring alterations in the phosphorylation status of proteins downstream of the epidermal growth factor receptor (EGFR) signaling cascade. TiO2-NPs blocked ligand-induced EGFR autophosphorylation, leading to the deactivation of EGFR downstream effectors such as Akt and extracellular signal-regulated kinase signaling, inducing cell death.


Assuntos
Apoptose , Nanopartículas Metálicas , Transdução de Sinais , Titânio , Apoptose/efeitos dos fármacos , Neoplasias da Mama , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Nanopartículas Metálicas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Titânio/toxicidade
9.
Environ Res ; 175: 316-322, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31146103

RESUMO

Phthalates are mainly used as binders and plasticizers in various industrial products including detergents, surfactants, waxes, paints, pharmaceuticals, food products, and cosmetics. However, they have been reported to be endocrine disruptors, which are chemicals that can mimic or disturb endocrines, causing interference to the endocrine system. Recently, there have been numerous reports showing that phthalates have negative health impacts such as asthma, breast cancer, obesity, type II diabetes, and male infertility. Due to these effects, there is an urgent need for phthalate alternatives. In this study, the potential cytotoxicity of phthalates and their substitutes were screened in HaCaT cells, a human keratinocyte cell line, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) thiazolyl blue assay, immunocytochemistry, flow cytometric analysis, and western blotting. We confirmed that common phthalates such as butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP) have genotoxic effects, leading to cell death. Among the known phthalate substitutes, tributyl O-acetylcitrate (ATBC), triethyl 2-acetylcitrate (ATEC), and trihexyl O-acetylcitrate (ATHC) were tested for cytotoxicity. As a result, ATEC showed similar levels of cytotoxicity with the phthalates whereas ATBC and ATHC did not show significant cytotoxicity even in high doses (5 mg/ml).


Assuntos
Poluentes Ambientais/toxicidade , Ácidos Ftálicos/toxicidade , Testes de Toxicidade/métodos , Diabetes Mellitus Tipo 2 , Dibutilftalato , Humanos , Queratinócitos , Plastificantes
10.
Environ Res ; 164: 655-659, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29631224

RESUMO

Bisphenol-A (BPA) was first synthesized in the 1890s and has been used in many plastic products. However, BPA is known to act as an endocrine disruptor and has been found to be toxic to human health. Many alternative substances have been developed to replace BPA, but it is still widely used worldwide. In this study, we identified the potential cytotoxicity of BPA by evaluating toxicity using human keratinocytes. Also, we evaluated cytotoxicity of BPA substitutes to determine their suitability as an alternative to BPA. The proliferation assay using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry and western blot analysis showed that BPA significantly affect cell viability, induction of apoptotic fraction and increased activation of DNA-damage marker protein. In addition, through the same experiments, the substitutes of BPA were shown to be significantly less toxic than BPA, and the least toxicity was observed with 1,4-cyclohexanedimethanol (CHDM) and terephthalic acid (TPA). In conclusion, this study suggests that cytotoxicity of BPA induces apoptosis of human keratinocytes, and that CHDM and TPA are the most suitable substitutes for BPA.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos , Queratinócitos , Fenóis/toxicidade , Humanos
11.
Drug Chem Toxicol ; 41(4): 486-491, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29124983

RESUMO

Nonylphenol polyethoxylates (NPEOs) are a major group of nonionic surfactants widely used in various detergents, cleaners, plastics, papers, and agro-chemical products. Nonylphenol (NP), which is a final degraded metabolite derived from NPEOs, has been reported as an endocrine disrupter, known to mimic or disturb reproductive hormone functions. Concern about the hazards of NP and NPEOs has generated legal restrictions and action plans worldwide. Considering the fact that NP and NPEOs are majorly used in the production of products such as detergents, shampoos, and cosmetics which frequently come into contact with the skin, we investigated the effects of NP and NPEOs on a human keratinocyte cell line (HaCaT). In this study, the toxicity of NP and NPEOs was screened in HaCaT cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide thiazolyl blue assay and Western blotting. The potential cytotoxicity of substitutes was assessed by dose-response assays, relative cell viability, and genotoxicity caused by specific alterations in DNA damage response proteins (including ataxia-telangiectasia mutated, p53, Chk1, Chk2, and Histone H2A.X). We demonstrated that NP and NPEOs are toxic to HaCaT cells, as revealed by the decreased cell viability after 24 h treatment. NPs and NPEOs also induced apoptosis and DNA damage as shown by the activation of Poly(ADP-ribose) polymerase, Caspase-3, and Histone H2A.X.


Assuntos
Queratinócitos/efeitos dos fármacos , Fenóis/toxicidade , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Humanos
12.
Arch Biochem Biophys ; 636: 110-122, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-28803837

RESUMO

Cancer cells require increased aerobic glycolysis to support rapid cell proliferation. For their increased energy demands, cancer cells express glucose transporter (Glut) proteins at a high level. Glut1 is associated with basal-like breast cancer and is considered a potential therapeutic target. To investigate the possibility of Glut1 as a therapeutic target in breast cancer cells, we downregulated Glut1 in triple-negative breast cancer (TNBC) cell lines using a short hairpin system. We determined whether Glut1 silencing might enhance anti-proliferative effect of chemotherapeutic agents. Contrary to our hypothesis, ablation of Glut1 attenuated apoptosis and increased drug resistance via upregulation of p-Akt/p-GSK-3ß (Ser9)/ß-catenin/survivin. These results indicated that the potential of Glut1 as a therapeutic target should be carefully reevaluated.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Transportador de Glucose Tipo 1/biossíntese , Glicogênio Sintase Quinase 3 beta/biossíntese , Proteínas Inibidoras de Apoptose/biossíntese , Proteínas Proto-Oncogênicas c-akt/biossíntese , Transdução de Sinais , Regulação para Cima , beta Catenina/biossíntese , Linhagem Celular Tumoral , Feminino , Transportador de Glucose Tipo 1/genética , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Proto-Oncogênicas c-akt/genética , Survivina , beta Catenina/genética
13.
Biochem J ; 473(19): 3013-30, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27458252

RESUMO

Cluster of differentiation 44 (CD44) is a transmembrane glycoprotein that has been identified as a cancer stem cell marker in various cancer cells. Although many studies have focused on CD44 as a cancer stem cell marker, its effect on cancer cell metabolism remains unclear. To investigate the role of CD44 on cancer cell metabolism, we established CD44 knock-down cells via retroviral delivery of shRNA against CD44 in human breast cancer cells. Silencing of CD44 decreased the glycolytic phenotype of cancer cells, affecting glucose uptake, ATP production, and lactate production. We also found that ablation of the CD44-induced lactate dehydrogenase (LDH) isoenzyme results in a shift to LDH1 due to LDHA down-regulation and LDHB up-regulation, implying the importance of LDH isoenzyme modulation on cancer metabolism. The expression of glycolysis-related proteins including hypoxia inducible factor-1α (HIF-1α) and LDHA was decreased by CD44 silencing. These effects were due to the up-regulation of liver kinase B1 (LKB1)/AMP-activated protein kinase (AMPK)α activity by reduction in c-Src and Akt activity in CD44 knock-down cells. Finally, induction of LKB1/AMPKα activity blocked the expression of HIF-1α and its target gene, LDHA. Inversely, LDHB expression was repressed by HIF-1α. Collectively, these results indicate that the CD44 silencing-induced metabolic shift is mediated by the regulation of c-Src/Akt/LKB1/AMPKα/HIF-1α signaling in human breast cancer cells.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Receptores de Hialuronatos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Trifosfato de Adenosina/biossíntese , Linhagem Celular Tumoral , Inativação Gênica , Glucose/metabolismo , Glicólise , Humanos , Receptores de Hialuronatos/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lactatos/metabolismo , Fosforilação Oxidativa , Regiões Promotoras Genéticas , RNA Mensageiro/genética
14.
Exp Cell Res ; 333(1): 116-26, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25743092

RESUMO

Fibronectin (FN), an extracellular matrix ligand, plays a pivotal role in cell adhesion, migration, and oncogenic transformation. Aberrant FN expression is associated with poor prognoses in various types of cancer, including breast cancer. In the current study, we investigated the relationship between FN induction and HER2 expression in breast cancer cells. Our results showed that the level of FN expression increased in response to HER family ligands, EGF and TGF-α in a time- and dose-dependent manner. On the other hand, EGF-induced FN expression decreased in response to trastuzumab, which is a HER2-targeted monoclonal antibody. However, EGF-induced FN expression was not affected by trastuzumab in JIMT-1 breast cancer cells, which are trastuzumab insensitive cells. Next, we introduced the HER2 gene into MDA-MB231 cells to verify the relationship between FN and HER2. The level of FN expression significantly increased in HER2-overexpressed MDA-MB231 cells. In contrast, the induction of FN by HER2 was significantly decreased in response to trastuzumab treatment. In addition, the induction of FN by HER2 was down-regulated by the MEK 1/2 specific inhibitor, U0126. Using conditioned culture media of vec- and HER2-overexpressed MDA-MB231 cells, we observed the cell morphology, adhesion, and invasion of MDA-MB231 cells. Interestingly, in conditioned culture media of HER2-overexpressed MDA-MB231 cells, the cell morphology was altered, and adhesion and invasion of MDA-MB231 cells significantly increased. In addition, our results showed that recombinant human FN augmented cell adhesion and invasion of MDA-MB231 cells while these inductions decreased in response to an FN inhibitor. Therefore, we demonstrated that the induction of FN by HER2 triggers cell adhesion and invasion capacities.


Assuntos
Adesão Celular , Fibronectinas/metabolismo , Receptor ErbB-2/fisiologia , Ativação Transcricional , Neoplasias da Mama , Linhagem Celular Tumoral , Forma Celular , Fator de Crescimento Epidérmico/fisiologia , Feminino , Fibronectinas/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , Invasividade Neoplásica , Fator de Crescimento Transformador alfa/fisiologia
15.
Arch Biochem Biophys ; 575: 69-76, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25935365

RESUMO

Members of the EGFR family are potent mediators of normal cell growth and development. HER2 possesses an active tyrosine kinase domain, but no direct ligand has been identified. To investigate the differential effect of HER2 in breast cell lines, HER2 was overexpressed in MCF-10A, MCF7 and MDA-MB-231 cells. HER2 overexpression promoted proliferation, survival and migration in MCF-10A and MCF-7 cells. No significant differences were seen in proliferation, survival or migration between MDA-MB-231 vec and HER2 cells. The activity of downstream HER2 proteins increased in MCF-10A HER2 and MCF-7 HER2 cells but not in MDA-MB-231 HER2 cells. Exogenously expressed HER2 failed to associate with EGFR or HER3 in MDA-MB-231 cells, while overexpression of HER2 enhanced HER family dimerization in MCF-10A and MCF-7 cells.


Assuntos
Proliferação de Células/genética , Receptores ErbB/fisiologia , Genes erbB-2 , Sequência de Bases , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Primers do DNA , Feminino , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Breast Cancer Res ; 16(6): 479, 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-25499743

RESUMO

INTRODUCTION: Extracellular matrix protein 1 (ECM1) is a secreted glycoprotein with putative functions in cell proliferation, angiogenesis and differentiation. Expression of ECM1 in several types of carcinoma suggests that it may promote tumor development. In this study, we investigated the role of ECM1 in oncogenic cell signaling in breast cancer, and potential mechanisms for its effects. METHODS: In order to find out the functional role of ECM1, we used the recombinant human ECM1 and viral transduction systems which stably regulated the expression level of ECM1. We examined the effect of ECM1 on cell proliferation and cell signaling in vitro and in vivo. Moreover, tissues and sera of patients with breast cancer were used to confirm the effect of ECM1. RESULTS: ECM1 protein was increased in trastuzumab-resistant (TR) cells, in association with trastuzumab resistance and cell proliferation. Through physical interaction with epidermal growth factor receptor (EGFR), ECM1 potentiated the phosphorylation of EGFR and extracellular signal-regulated kinase upon EGF treatment. Moreover, ECM1-induced galectin-3 cleavage through upregulation of matrix metalloproteinase 9 not only improved mucin 1 expression, but also increased EGFR and human epidermal growth factor receptor 3 protein stability as a secondary signaling. CONCLUSIONS: ECM1 has important roles in both cancer development and trastuzumab resistance in breast cancer through activation of EGFR signaling.


Assuntos
Adenocarcinoma/genética , Anticorpos Monoclonais Humanizados , Antineoplásicos , Neoplasias da Mama/genética , Proliferação de Células/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas da Matriz Extracelular/genética , RNA Mensageiro/metabolismo , Adenocarcinoma/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Galectina 3/metabolismo , Humanos , Células MCF-7 , Metaloproteinase 9 da Matriz/metabolismo , Camundongos Nus , Mucina-1/metabolismo , Transplante de Neoplasias , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Transdução de Sinais , Trastuzumab
17.
Arch Biochem Biophys ; 558: 120-6, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24977325

RESUMO

We report here that CD24 knockdown resulted in decreased expression of Notch1 in MCF-7 cells. CD24-downstream p38MAPK was shown to regulate Notch1 at the level of mRNA stability. We also found that CD24-mediated cell migration, invasion, mammosphere formation, and drug resistance was regulated by its downstream target Notch1. Together, our results indicate that CD24 may regulate the epithelial to mesenchymal transition and stemness through Notch1 signaling in breast cancer cells.


Assuntos
Antígeno CD24/metabolismo , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/patologia , Estabilidade de RNA , Receptor Notch1/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Antígeno CD24/genética , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Fenótipo , RNA Mensageiro/química
18.
Exp Cell Res ; 319(3): 122-33, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23200933

RESUMO

Autophagy, or autophagocytosis, is a selective intracellular degradative process involving the cell's own lysosomal apparatus. An essential component in cell development, homeostasis, repair and resistance to stress, autophagy may result in either cell death or survival. The targeted region of the cell is sequestered within a membrane structure, the autophagosome, for regulation of the catabolic process. A key factor in both autophagosome formation and autophagosome maturation is a protein encoded by the ultraviolet irradiation resistance-associated gene (UVRAG). Conversely, the serine/threonine-specific protein kinase B (PKB, also known as Akt), which regulates survival in various cancers, inhibits autophagy through mTOR activation. We found that Akt1 may also directly inhibit autophagy by down-regulating UVRAG both in a 293T transient transfection system and breast cancer cells stably expressing Akt1. The UVRAG with mutations at putative Akt1-phosphorylation sites were still inhibited by Akt1, and dominant-negative Akt1 also inhibited UVRAG expression, suggesting that Akt1 down-regulates UVRAG by a kinase activity-independent mechanism. We showed that Akt1 overexpression in MDA-MB-231 breast cancer cells down-regulated UVRAG transcription. Cells over-expressing Akt1 were more resistant than control cells to ultraviolet light-induced autophagy and exhibited the associated reduction in cell viability. Levels of the autophagosome indicator protein LC3B-II and mRFP-GFP-LC3 were reduced in cells that over-expressing Akt1. Inhibiting Akt1 by siRNA or reintroducing UVRAG gene rescued the level of LC3B-II in UV-irradiation. Altogether, these data suggest that Akt1 may inhibit autophagy by decreasing UVRAG expression, which also sensitizes cancer cells to UV irradiation.


Assuntos
Autofagia/genética , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Supressoras de Tumor/genética , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Autofagia/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação para Baixo/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Neoplasias/genética , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/farmacologia , Transfecção , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/metabolismo , Raios Ultravioleta
19.
Biochem J ; 451(1): 123-34, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23323858

RESUMO

In breast cancer, the HER2 (human epidermal growth factor receptor 2) receptor tyrosine kinase is associated with extremely poor prognosis and survival. Notch signalling has a key role in cell-fate decisions, especially in cancer-initiating cells. The Notch intracellular domain produced by Notch cleavage is translocated to the nucleus where it activates transcription of target genes. To determine the combinatory effect of HER2 and Notch signalling in breast cancer, we investigated the effect of HER2 on Notch-induced cellular phenomena. We found the down-regulation of Notch-dependent transcriptional activity by HER2 overexpression. Also, the HER2/ERK (extracellular-signal-regulated kinase) signal pathway down-regulated the activity of γ-secretase. When we examined the protein level of Notch target genes in HER2-overexpressing cells, we observed that the level of survivin, downstream of Notch, increased in HER2 cells. We found that activation of ERK resulted in a decrease in XAF1 [XIAP (X-linked inhibitor of apoptosis)-associated factor 1] which reduced the formation of the XIAP-XAF1 E3 ligase complex to ubiquitinate survivin. In addition, Thr(34) of survivin was shown to be the most important residue in determining survivin stability upon phosphorylation after HER2/Akt/CDK1 (cyclin-dependent kinase 1)-cyclin B1 signalling. The results of the present study show the combinatorial effects of HER2 and Notch during breast oncogenesis.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas Inibidoras de Apoptose/biossíntese , Sistema de Sinalização das MAP Quinases , Proteólise , Receptor ErbB-2/metabolismo , Receptores Notch/metabolismo , Transcrição Gênica , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas Reguladoras de Apoptose , Neoplasias da Mama/genética , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Células COS , Chlorocebus aethiops , Regulação para Baixo/genética , Feminino , Células HeLa , Humanos , Proteínas Inibidoras de Apoptose/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/genética , Receptores Notch/química , Survivina , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
20.
Biomimetics (Basel) ; 9(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38534835

RESUMO

The current motion interaction model has the problems of insufficient motion fidelity and lack of self-adaptation to complex environments. To address this problem, this study proposed to construct a human motion control model based on the muscle force model and stage particle swarm, and based on this, this study utilized the deep deterministic gradient strategy algorithm to construct a motion interaction control model based on the muscle force model and the deep reinforcement strategy. Empirical analysis of the human motion control model proposed in this study revealed that the joint trajectory correlation and muscle activity correlation of the model were higher than those of other comparative models, and its joint trajectory correlation was up to 0.90, and its muscle activity correlation was up to 0.84. In addition, this study validated the effectiveness of the motion interaction control model using the depth reinforcement strategy and found that in the mixed-obstacle environment, the model's desired results were obtained by training 1.1 × 103 times, and the walking distance was 423 m, which was better than other models. In summary, the proposed motor interaction control model using the muscle force model and deep reinforcement strategy has higher motion fidelity and can realize autonomous decision making and adaptive control in the face of complex environments. It can provide a theoretical reference for improving the effect of motion control and realizing intelligent motion interaction.

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