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1.
Nanotechnology ; 33(15)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34952533

RESUMO

Voltage-driven stochastic magnetization switching in a nanomagnet has attracted more attention recently with its superiority in achieving energy-efficient artificial neuron. Here, a novel pure voltage-driven scheme with ∼27.66 aJ energy dissipation is proposed, which could rotate magnetization vector randomly using only a pair of electrodes covered on the multiferroic nanomagnet. Results show that the probability of 180° magnetization switching is examined as a sigmoid-like function of the voltage pulse width and magnitude, which can be utilized as the activation function of designed neuron. Considering the size errors of designed neuron in fabrication, it's found that reasonable thickness and width variations cause little effect on recognition accuracy for MNIST hand-written dataset. In other words, the designed pure voltage-driven spintronic neuron could tolerate size errors. These results open a new way toward the realization of artificial neural network with low power consumption and high reliability.

2.
Mol Ther ; 28(4): 1105-1118, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32059763

RESUMO

RNA-binding proteins (RBPs) play fundamental roles in cancer; however, we still lack knowledge about to what extent RBPs are dysregulated, as well as about perturbed signaling pathways in cancer. In this study, we integrated analysis of multidimensional data across >10,000 cancer patients and >1,000 cell lines. We identified a top candidate RBP: eukaryotic translation initiation factor 2 subunit beta (EIF2S2). EIF2S2 is highly expressed in tumors and is associated with malignant features as well as patient prognosis. Functional assays performed in cancer cells revealed that EIF2S2 promotes cancer cell proliferation, migration, and invasion in vitro as well as tumor growth and metastasis in vivo. Mechanistic investigations further demonstrated that EIF2S2 promotes tumorigenesis and progression by directly binding to a long non-coding RNA, LINC01600, which physically interacts with the MYC protein and increases its stability. Interestingly, we revealed that the EIF2S2-LINC01600-MYC axis can activate the Wnt/ß-catenin pathway by inhibiting the activity of FHIT-related enhancers and FHIT expression. Finally, EIF2S2 knockdown combined with oxaliplatin treatment could be a potential combination therapy in cancer. Our integrated analysis provided detailed knowledge of the function of the EIF2S2-LINC01600-MYC axis, which will facilitate the development of rational combination therapies for cancer.


Assuntos
Neoplasias Colorretais/patologia , Fator de Iniciação 2 em Eucariotos/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Progressão da Doença , Fator de Iniciação 2 em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Células HCT116 , Células HT29 , Humanos , Oxaliplatina/farmacologia , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/química , Regulação para Cima/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
3.
Mol Cancer ; 19(1): 51, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32127004

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) are emerging as critical regulatory elements and play fundamental roles in the biology of various cancers. However, we are still lack of knowledge about their expression patterns and functions in human colorectal cancer (CRC). METHODS: Differentially expressed lncRNAs in CRC were identified by bioinformatics screen and the level of MIR22HG in CRC and control tissues were determined by qRT-PCR. Cell viability and migration capacities were examined by MTT and transwell assay. Mouse model was used to examine the function and rational immunotherapy of MIR22HG in vivo. RESULTS: We systematically investigated the expression pattern of lncRNAs and revealed MIR22HG acts as a tumor suppressor in CRC. The expression of MIR22HG was significantly decreased in CRC, which was mainly driven by copy number deletion. Reduced expression of MIR22HG was significantly associated with poor overall survival. Silencing of MIR22HG promoted cell survival, proliferation and tumor metastasis in vitro and in vivo. Mechanistically, MIR22HG exerts its tumor suppressive activity by competitively interacting with SMAD2 and modulating the activity of TGFß pathway. Decreased MIR22HG promoted the epithelial-mesenchymal transition in CRC. Importantly, we found that MIR22HG expression is significantly correlated with CD8A and overexpression of MIR22HG triggers T cell infiltration, enhancing the clinical benefits of immunotherapy. CONCLUSION: MIR22HG acts as a tumor suppressor in CRC. Our data provide mechanistic insights into the regulation of MIR22HG in TGFß pathway and facilitates immunotherapy in cancer.


Assuntos
Neoplasias Colorretais/patologia , Imunoterapia/métodos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , MicroRNAs/genética , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Proteína Smad2/genética , Taxa de Sobrevida , Fator de Crescimento Transformador beta1/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
MedComm (2020) ; 5(5): e521, 2024 May.
Artigo em Catalão | MEDLINE | ID: mdl-38660687

RESUMO

This study systematically analyzed the molecular mechanism and function of nuclear factor kappa B subunit 2 (NFKB2) in colorectal cancer (CRC) to investigate the potential of NFKB2 as a therapeutic target for CRC. Various experimental techniques, including RNA sequencing, proteome chip assays, and small molecule analysis, were used to obtain a deeper understanding of the regulation of NFKB2 in CRC. The results revealed that NFKB2 was upregulated in a significant proportion of patients with advanced hepatic metastasis of CRC. NFKB2 played an important role in promoting tumor growth through CD8+ T-cell exhaustion. Moreover, NFKB2 directly interacted with signal transducer and activator of transcription 2 (STAT2), leading to increased phosphorylation of STAT2 and the upregulation of programmed death ligand 1 (PD-L1). Applying a small molecule inhibitor of NFKB2 (Rg5) led to a reduction in PD-L1 expression and improved response to programmed death-1 blockade-based immunotherapy. In conclusion, the facilitated NFKB2-STAT2/PD-L1 axis may suppress immune surveillance in CRC and targeting NFKB2 may enhance the efficacy of immunotherapeutic strategies. Our results provide novel insights into the molecular mechanisms underlying the contribution of NFKB2 in CRC immune escape.

7.
BMC Microbiol ; 13: 87, 2013 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-23594351

RESUMO

BACKGROUND: The prevalence of drug-resistant bacteria has encouraged the search for novel antimicrobial compounds. Food-associated microorganisms, as a source of new antibiotics, have recently received considerable attention. The objective of this study was to find novel antimicrobial agents produced by food microorganisms. RESULTS: A bacterial strain B7, which has potent antimicrobial activity, was isolated from a sample of dairy waste. This strain was identified as Paenibacillus ehimensis based on the 16S rRNA gene sequence analysis, physiological and biochemical characterization. Two active compounds (PE1 and PE2) were obtained from P. ehimensis B7. Mass spectrometry (MS) analysis showed that the molecular masses of PE1 and PE2 were 1,114 and 1,100 Da, respectively. The tandem MS and amino acid analysis indicated that PE1 and PE2 were analogs of polypeptin, and PE2 was characterized as a new member of this family. Both compounds were active against all tested bacterial pathogens, including methicillin resistant Staphylococcus aureus, Escherichia coli, and pan-drug resistant Pseudomonas aeruginosa clinical isolate. Time-kill assays demonstrated that at 4 × MIC (minimum inhibitory concentration), PE1 and PE2 rapidly reduced the number of viable cells by at least 3-orders of magnitude, indicating that they were bactericidal antibiotics. CONCLUSIONS: In the present work, two cationic lipopeptide antibiotics (PE1 and PE2) were isolated from P. ehimensis B7 and characterized. These two peptides showed broad antimicrobial activity against all tested human pathogens and are worthy of further study.


Assuntos
Antibacterianos/biossíntese , Lipopeptídeos/biossíntese , Paenibacillus/química , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Paenibacillus/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Espectrometria de Massas em Tandem
8.
Exp Mol Pathol ; 91(3): 702-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21884695

RESUMO

This study was aimed to evaluate the clinical value of plasma methylation analysis of a panel of four genes (APC, GSTP1, RASSF1A, and SFRP1), which was identified by our previous work, for the noninvasive diagnosis of hepatocellular carcinoma (HCC). The methylation status of these four genes in 150 plasma samples from 72 patients with HCC, 37 benign live diseases and 41 normal controls was detected with methylation-sensitive restriction enzymes-based quantitative PCR (MSRE-qPCR) method. The plasma methylation levels of APC, GSTP1, RASSF1A, and SFRP1 were significantly higher in HCCs than those in normal or benign controls (P<0.05). Although the area under the receiver-operation characteristic curve (AUC-ROC) for individual gene was moderate (range, from 0.800 to 0.881), the combination analysis of these four genes resulted in an increased AUC of 0.933 with 92.7% sensitivity, 81.9% specificity, 90.5% positive predictive value (PPV), and 87.2% negative predictive value (NPV) in discriminating HCC from normal control. The combination analysis also indicated an increased AUC of 0.877 when compared with individual gene (from 0.666 to 0.850) in discriminating HCC from benign control, and the consultant sensitivity, specificity, PPV, and NPV was 84.7%, 81.1%, 89.7%, and 73.2%, respectively. Patients with elevated plasma methylation levels of APC or RASSF1A showed poorer overall survival than those with low levels (P<0.05). Cox multivariate analysis demonstrated methylated RASSF1A in plasma to be an independent prognostic factor for overall survival (hazard ratio=3.262, 95% CI: 1.476-7.209, P=0.003). These data showed that quantitative analysis of multiple methylated genes in plasma may be a promising tool for noninvasive diagnosis of HCC; and methylated plasma RASSF1A appears to be a prognostic marker of HCC.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular/genética , Metilação de DNA , Neoplasias Hepáticas/genética , Proteínas Supressoras de Tumor , Adulto , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Feminino , Glutationa S-Transferase pi/sangue , Glutationa S-Transferase pi/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/genética , Fígado/metabolismo , Hepatopatias/sangue , Hepatopatias/diagnóstico , Hepatopatias/genética , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Masculino , Proteínas de Membrana/sangue , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Prognóstico , Proteínas Supressoras de Tumor/sangue , Proteínas Supressoras de Tumor/genética
9.
Front Oncol ; 10: 639, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670860

RESUMO

Colorectal cancer (CRC) is a common cancer worldwide, with a lower 5-years survival rate. Recently, long non-coding RNAs (lncRNAs) have been well-studied as the oncogenes or the tumor suppressors in multiple malignancies, including CRC. However, their biological functions and potential mechanisms in human cancer remain unclear. Here, we evaluated the expression of TDRKH-AS1 in CRC tissues and identified its potential targets. We found that TDRKH-AS1 is upregulated in majority of CRC patients, which is also significantly correlated with their malignant characteristics and their dismal prognoses. The high expression of TDRKH-AS1 can promote cancer cell proliferation substantially and invasion based on in vitro experiments. We also recognized that the TDRKH-AS1 targets the ß-catenin in the Wnt signaling pathway to exert its carcinogenic activity. TDRKH-AS1 could serve as a promising prognostic predictor and a potential therapeutic target for further early diagnoses and treatments via a non-invasive method.

10.
World J Gastroenterol ; 14(41): 6401-7, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-19009659

RESUMO

AIM: To determine the influence of excision repair cross complementing group 1 (ERCC1) codon 118 polymorphism and mRNA level on the clinical outcome of gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy. METHODS: Eighty-nine gastric cancer patients treated with oxalipatin-based adjuvant chemotherapy were included in this study. ERCC1 codon 118 C/T polymorphism was tested by polymerase chain reaction-ligation detection reaction (PCR-LDR) method in peripheral blood lymphocytes of those patients; and the intratumoral ERCC1 mRNA expression was measured using reverse transcription PCR in 62 patients whose tumor tissue specimens were available. RESULTS: No significant relationship was found between ERCC1 codon 118 polymorphism and ERCC1 mRNA level. The median relapse-free and overall survival period was 20.1 mo and 28.4 mo, respectively. The relapse-free and overall survivals in patients with low levels of ERCC1 mRNA were significantly longer than those in patients with high levels (P<0.05), while there was no significant association found between ERCC1 118 genotypes and the disease prognosis. Multivariate analysis also showed that ERCC1 mRNA level was a potential predictor for relapse and survival in gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy (P<0.05). CONCLUSION: ERCC1 codon 118 polymorphism has no significant impact on ERCC1 mRNA expression, and the intratumoral ERCC1 mRNA level but not codon 118 polymorphism may be a useful predictive parameter for the relapse and survival of gastric cancer patients receiving oxaliplatin-based adjuvant chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Gastrectomia , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Quimioterapia Adjuvante , Códon , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Razão de Chances , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Modelos de Riscos Proporcionais , RNA Mensageiro/análise , Medição de Risco , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Fatores de Tempo , Resultado do Tratamento
11.
Gene ; 578(2): 177-84, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26692142

RESUMO

The development of colorectal cancers (CRC) is accompanied with the acquisition and maintenance of specific genomic alterations. These alterations can emerge in premalignant adenomas and faithfully maintained in highly advanced tumors. miRNAs are a class of small non-coding RNAs that are frequently deregulated in human cancers and negatively regulate a wide variety of protein coding genes. To identify the sequential alterations of miRNAs and its regulatory networks during CRC development and progression, we detected the miRNA expression profiles of tissue samples from normal colon, colorectal adenoma and CRC using miRNA microarray. qRT-PCR assay was used to validate and select the miRNAs with differential expression among the three groups, and the computer-aided algorithms of TargetScan, miRanda, miRwalk, RNAhybrid and PicTar were used to search for the possible targets of the selected 8 miRNAs (miR-18a, miR-18b, miR-31, miR-142-5p, miR-145, miR-212, miR-451, and miR-638) with continuous alterated expression. These potential target genes were enriched in several key signal transduction pathways (KEGG pathway analysis), which have been proved to be closely related to colorectal tumorigenesis. To confirm the reliability of the analyses, we identified that the metastasis-related gene ZO-1 is a certain target of miR-212 in CRC and keeps declining during CRC progression. By following these analyses, we might gain an in-depth understanding of the molecular regulatory networks of colorectal tumorigenesis and provide new potential targets for the diagnostic and therapeutic interventions of this disease.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , MicroRNAs/biossíntese , Proteína da Zônula de Oclusão-1/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , MicroRNAs/genética , Proteína da Zônula de Oclusão-1/biossíntese
13.
Med Oncol ; 32(1): 331, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25429829

RESUMO

MicroRNAs (miRNAs) are a type of small noncoding RNAs that are strongly implicated in carcinogenesis. However, the potential diagnostic, prognostic and therapeutic roles of the majority of miRNAs in the pathological processes of tumorigenesis remain largely unknown. Our and others' data revealed that miR-204-5p was significantly downregulated in gastrointestinal tumor tissues compared with adjacent noncancerous tissues. The downregulation of miR-204-5p was confirmed in our gastric cancer (GC) cohort, and we showed that ectopic expression of miR-204-5p inhibited, whereas silencing miR-204-5p expression promoted GC cell proliferation in vitro. Subsequent mechanistic investigations identified that USP47 and RAB22A are direct functional targets of miR-204-5p in GC. Silencing the expression of USP47 and RAB22A using siRNA phenocopied the proliferation-inhibiting function of miR-204-5p in GC cells. Our results uncovered that miR-204-5p acts as a tumor suppressor in GC through inhibiting USP47 and RAB22A.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Neoplasias Gástricas/genética , Ubiquitina Tiolesterase/biossíntese , Proteínas rab de Ligação ao GTP/biossíntese , Western Blotting , Regulação para Baixo , Humanos , Imuno-Histoquímica , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Ubiquitina Tiolesterase/genética , Proteases Específicas de Ubiquitina , Proteínas rab de Ligação ao GTP/genética
14.
Protein Cell ; 6(9): 680-688, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26250158

RESUMO

MicroRNAs (miRNAs) are a type of small non-coding RNAs that are often play important roles in carcinogenesis, but the carcinogenic mechanism of miRNAs is still unclear. This study will investigate the function and the mechanism of miR-638 in carcinoma (GC). The expression of miR-638 in GC and the DNA copy number of miR-638 were detected by real-time PCR. The effect of miR-638 on cell proliferation was measured by counting kit-8 assay. Different assays, including bioinformatics algorithms (TargetScan and miRanda), luciferase report assay and Western blotting, were used to identify the target gene of miR-638 in GC. The expression of miR-638 target gene in clinical CRC tissues was also validated by immunohistochemical assay. From this research, we found that miR-638 was downregulated in GC tissues compared with corresponding noncancerous tissues (NCTs), and the DNA copy number of miR-638 was lower in GC than NCTs, which may induce the corresponding downregulation of miR-638 in GC. Ectopic expression of miR-638 inhibited GC cell growth in vitro. Subsequently, we identified that PLD1 is the target gene of miR-638 in GC, and silencing PLD1 expression phenocopied the inhibitory effect of miR-638 on GC cell proliferation. Furthermore, we observed that PLD1 was overexpressed in GC tissues, and high expression of PLD1 in GC predicted poor overall survival. In summary, we revealed that miR-638 functions as a tumor suppressor in GC through inhibiting PLD1.


Assuntos
MicroRNAs/genética , Fosfolipase D/genética , Neoplasias Gástricas/patologia , Regiões 3' não Traduzidas/genética , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Humanos , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética
15.
Oncotarget ; 5(23): 12083-96, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25301729

RESUMO

The expression of miR-638 was found downregulated in colorectal carcinoma (CRC) in our previous study. However, the role of miR-638 in CRC remains unknown. The aim of this study was to determine the function and mechanism of miR-638 in CRC. Here, we verified that miR-638 was frequently downregulated in CRC tissues compared with corresponding noncancerous tissues (NCTs) in an expanded CRC cohort, and survival analysis showed that the downregulation of miR-638 in CRC was associated with poor prognoses. The ectopic expression of miR-638 inhibited CRC cell proliferation, invasion and arrest the cell cycle in G1 phase, whereas the repression of miR-638 significantly promoted CRC cell growth, invasion and cell cycle G1/S transition. Subsequent mechanism analyses revealed that miR-638 inhibited CRC cell growth, invasion and cell cycle progression by targeting TSPAN1. TSPAN1 protein levels were upregulated in CRC samples and were inversely correlated with miR-638 levels. More importantly, high TSPAN1 expression levels in CRC tissues predicted poor overall survival, and appears to be an independent prognostic factor for CRC survival. Furthermore, CpG island methylation analyses revealed that the miR-638 promoter was hypermethylated in CRC and that attenuating promoter methylation was sufficient to restore miR-638 expression in CRC cells. Taken together, our current data demonstrate that miR-638 functions as a tumor suppressor in human CRC by inhibiting TSPAN1, and that TSPAN1 is a potential prognostic factor for CRC.


Assuntos
Ciclo Celular/genética , Proliferação de Células , Neoplasias Colorretais/genética , MicroRNAs/genética , Tetraspaninas/biossíntese , Animais , Sequência de Bases , Western Blotting , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor , Xenoenxertos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
16.
Protein Cell ; 5(11): 851-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25149074

RESUMO

MicroRNAs (miRNAs) that exert function by posttranscriptional suppression have recently brought insight in our understanding of the role of non-protein-coding RNAs in carcinogenesis and metastasis. In this study, we described the function and molecular mechanism of miR-139-5p in colorectal cancer (CRC) and its potential clinical application in CRC. We found that miR-139-5p was significantly downregulated in 73.8% CRC samples compared with adjacent noncancerous tissues (NCTs), and decreased miR-139-5p was associated with poor prognosis. Functional analyses demonstrated that ectopic expression of miR-139-5p suppressed CRC cell migration and invasion in vitro and metastasis in vivo. Mechanistic investigations revealed that miR-139-5p suppress CRC cell invasion and metastasis by targeting AMFR and NOTCH1. Knockdown of the two genes phenocopied the inhibitory effect of miR-139-5p on CRC metastasis. Furthermore, the protein levels of the two genes were upregulated in CRC samples compared with NCTs, and inversely correlated with the miR-139-5p expression. Increased NOTCH1 protein expression was correlated with poor prognosis of CRC patients. Together, our data indicate that miR-139-5p is a potential tumor suppressor and prognostic factor for CRC, and targeting miR-139-5p may repress the metastasis of CRC and improve survival.


Assuntos
Movimento Celular/genética , Neoplasias Colorretais/genética , Regulação para Baixo , MicroRNAs/genética , Receptor Notch1/genética , Receptores do Fator Autócrino de Motilidade/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Interferência de RNA , Receptor Notch1/metabolismo , Receptores do Fator Autócrino de Motilidade/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Clin Cancer Res ; 20(23): 6187-99, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25294901

RESUMO

PURPOSE: miR-204-5p was found to be downregulated in colorectal cancer tissues in our preliminary microarray analyses. However, the function of miR-204-5p in colorectal cancer remains unknown. We therefore investigated the role, mechanism, and clinical significance of miR-204-5p in colorectal cancer development and progression. EXPERIMENTAL DESIGN: We measured the expression of miR-204-5p and determined its correlation with patient prognoses. Ectopic expression in colorectal cancer cells, xenografts, and pulmonary metastasis models was used to evaluate the effects of miR-204-5p on proliferation, migration, and chemotherapy sensitivity. Luciferase assay and Western blotting were performed to validate the potential targets of miR-204-5p after the preliminary screening by a microarray analysis and computer-aided algorithms. RESULTS: miR-204-5p is frequently downregulated in colorectal cancer tissues, and survival analysis showed that the downregulation of miR-204-5p in colorectal cancer was associated with poor prognoses. Ectopic miR-204-5p expression repressed colorectal cancer cell growth both in vitro and in vivo. Moreover, restoring miR-204-5p expression inhibited colorectal cancer migration and invasion and promoted tumor sensitivity to chemotherapy. Mechanistic investigations revealed that RAB22A, a member of the RAS oncogene family, is a direct functional target of miR-204-5p in colorectal cancer. Furthermore, RAB22A protein levels in colorectal cancer tissues were frequently increased and negatively associated with miR-204-5p levels and survival time. CONCLUSIONS: Our results demonstrate for the first time that miR-204-5p acts as a tumor suppressor in colorectal cancer through inhibiting RAB22A and reveal RAB22A to be a new oncogene and prognostic factor for colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteínas rab de Ligação ao GTP/genética , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Metilação de DNA , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Masculino , Camundongos , MicroRNAs/química , Prognóstico , Regiões Promotoras Genéticas , Interferência de RNA , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas rab de Ligação ao GTP/química
18.
Oncol Rep ; 26(5): 1305-13, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21769436

RESUMO

In the present study, we investigated the prognostic roles of the O6-methylguanine-DNA methyltransferase (MGMT) gene methylation status, the protein profiles of MGMT, and the glioma stem cell (GSC) marker CD133 in malignant glioma resistance to radiotherapy. The proliferation of glioma cells was assessed using a clonogenic survival assay and flow cytometry. CD133 expression was assessed in SHG-44-GSCs using RT-PCR and flow cytometry. MGMT exhibited resistance to radiation in the SHG-44-GSCs using siRNA transfection. The effects of the siRNA on mRNA and protein expression of MGMT in SHG-44-GSCs were detected using semi-quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting. MGMT methylation status, MGMT and CD133 expression profiles were assessed in 59 malignant glioma patients using methylation-specific polymerase chain reaction (MSP), and immunohistochemistry. In vitro, SHG-44-GSCs exhibited a characteristic resistance to radiation that was not observed in SHG-44 cells. This resistance was attributed to the unmethylated status of the MGMT promoter and to high expression levels of MGMT mRNA in the glioma cells. In these patients, the CD133 marker, but not MGMT promoter methylation or MGMT protein level, was associated with resistance to radiotherapy (n=59; hazard ratio=2.838; 95% CI, 1.725-7.597; p=0.001). The median progression-free survival (PFS) among patients with the CD133 marker was 14 months, whereas it was 35 months in patients without CD133 (p=0.001). Notably, co-expression of the methylated MGMT promoter and the CD133 marker was associated with the poorest outcome in patients with gliomas treated by radiotherapy; in these patients, PFS was 7 months. These results suggest that assessment of GSC MGMT and CD133 levels will guide future clinical targeted therapies and stratify glioma patient treatment regimens. High expression levels of the CD133 protein could be used as a predictor for poor survival in patients treated with radiotherapy.


Assuntos
Antígenos CD/biossíntese , Biomarcadores Tumorais/biossíntese , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Metilases de Modificação do DNA/biossíntese , Enzimas Reparadoras do DNA/biossíntese , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Glicoproteínas/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Antígeno AC133 , Adulto , Idoso , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Quimiorradioterapia Adjuvante , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Peptídeos , Prognóstico , Regiões Promotoras Genéticas , Tolerância a Radiação , Transfecção , Proteínas Supressoras de Tumor/genética
19.
Eur J Cancer Prev ; 18(4): 285-90, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19398914

RESUMO

Variants in several genes are known to confer increased susceptibility to breast cancer, but the frequencies of these mutations in the population are very rare and different between race or ethnic groups. Genetic variation in trinucleotide repeat containing 9 (TNRC9) and the hypothetical gene LOC643714 (TNRC9/LOC643714) is a newly described risk factor for breast cancer. Here, we investigated the association among the three single nucleotide polymorphisms (SNPs) in TNRC9/LOC643714 and breast cancer risk and clinico-pathological parameters in a hospital-based Chinese population. Genomic DNA was extracted from peripheral blood lymphocytes. Polymerase chain reaction-ligation detection reaction was used to genotype 321 breast cancer cases and 330 controls. In addition, the representative polymerase chain reaction products were subjected to direct DNA sequencing to confirm the accuracy of this method. The odds ratios and 95% confidence intervals were calculated by an unconditional logistic regression model. There was no significant association between the risk of breast cancer and three SNPs of TNRC9/LOC643714 gene polymorphisms and their haplotypes. No significant correlation was found between the TNRC9/LOC643714 polymorphisms and age at diagnosis, lymph node metastases, estrogen receptor status, or progesterone receptor status, respectively. None of these three SNPs of TNRC9/LOC643714 gene is associated with individual susceptibility to breast cancer in Chinese women.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Progesterona/genética , Proteínas Reguladoras de Apoptose , Neoplasias da Mama/epidemiologia , Feminino , Marcadores Genéticos/genética , Proteínas de Grupo de Alta Mobilidade , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Transativadores
20.
Artigo em Zh | MEDLINE | ID: mdl-20104772

RESUMO

OBJECTIVE: To construct chimerical DNA vaccine plasmid of human papillomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity. METHODS: Molecular cloning techniques were used to construct recombinant plasmid pcDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection.IL-2 and gamma-INF secreted by immunized spleens lymphocyte and HPV 11 L1 or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay. RESULTS: The chimerical DNA plasmid of pcDNA3 L1-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and gamma-INF were detected in vaccinated mice. CONCLUSION: Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.


Assuntos
Engenharia Genética , Papillomavirus Humano 11/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/genética , Vacinas contra Papillomavirus/imunologia , Vacinas de DNA/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Sequência de Bases , Feminino , Papillomavirus Humano 11/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Distribuição Aleatória , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética
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