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1.
Plant Dis ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679599

RESUMO

Cardamine violifolia, also called Cardamine hupingshanensis, is an economically important medicinal plant renowned for accumulating selenium (Guo et al., 2022). Selenium is an essential trace element with anti-oxidant, anti-inflammatory, anti-cancer, and immune regulatory functions. In July 2023, an outbreak of powdery mildew was detected, infecting the leaves of numerous C. violifolia plants in Enshi (30°11'5.27''N; 109°48'48.45''E), Hubei Province, China. This disease caused severe damage to plant leaves and stems, starting as individual spots and merging into a large mold that covers the entire leaf. It affected nearly 25% all C. violifolia plants, resulting in significant yield loss, disruption of normal metabolism, and premature aging. The lower leaf blades and underside of the leaves were particularly vulnerable. The affected leaves were collected and subjected to morphological diagnostic analysis (Mori et al., 2000) (Fig. S1). The powdery mildew species aggressively spread throughout the leaves, pedicels, and pods, persisting until present and often covering the entire surface. The conidiophores were upright, cylindrical, composed of 3 to 4 cells, and measured 92.3 ± 12.9 × 9.2 ± 0.6 µm (n = 30). Conidial pedicels had 21.6 ± 3.4 µm (n = 50) long cylindrical podocytes. The monoconidia were columnar or barrel-columnar, 30.60-55.59 × 9.11-20.00 µm in size. Conidia lacked an obvious cellulose body. The bud tubes formed from the end of conidia, and papillary appressoria developed on the epiphytic mycelia. ITS region sequences were amplified using the specific powdery mildew universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3'), PM6 (5'-GYCRCYCTGTCGCGAG-3') for partial sequences of 18S and 28S ribosomal DNA genes (Takamatsu et al., 2001). The sequence was deposited in the GenBank under the accession number OR506156 and aligned with available sequences on NCBI, which were 99.2%(528/532) identical to the E. cruciferarum (MT309701, MF192845, and KY660929) sequences (Fig. S2). The ITS sequence from GenBank was used to conduct maximum likelihood phylogenetic analysis using MEGA 11.0. The analysis results showed both the strain and E. cruciferarum clustered on the same branch. To confirm Koch's postulates, pathogenicity testing was carried out using an illuminating incubator. Infected leaves were attached to healthy leaves of C. violifolia seedlings (n=8). All the plants were incubated under 25℃ and >80% relative humidity. After one month, all inoculated plants presented the same symptoms as those initially observed in the field. Morphological and molecular analysis confirmed the isolated fungi's identity as the same pathogen. Therefore, C. violifolia is a suitable host for E. cruciferarum in China. The growers must be informed of these findings to prevent serious economic losses caused by this pathogenic white powder and to prepare for proper management practices. To our knowledge, this is the first report of E. cruciferarum infecting C. violifolia in China.

2.
Sensors (Basel) ; 24(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38544250

RESUMO

This paper introduces a novel data-driven self-triggered control approach based on a hierarchical reinforcement learning framework in networked motor control systems. This approach divides the self-triggered control policy into higher and lower layers, with the higher-level policy guiding the lower-level policy in decision-making, thereby reducing the exploration space of the lower-level policy and improving the efficiency of the learning process. The data-driven framework integrates with the dual-actor critic algorithm, using two interconnected neural networks to approximate the hierarchical policies. In this framework, we use recurrent neural networks as the network architecture for the critic, utilizing the temporal dynamics of recurrent neural networks to better capture the dependencies between costs, thus enhancing the critic network's efficiency and accuracy in approximating the multi-time cumulative cost function. Additionally, we have developed a pre-training method for the control policy networks to further improve learning efficiency. The effectiveness of our proposed method is validated through a series of numerical simulations.

3.
J Biol Chem ; 289(35): 24724-35, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25049231

RESUMO

MicroRNAs (miRNAs) have been shown to play important roles in carcinogenesis. However, their underlying mechanisms of action in hepatocellular carcinoma (HCC) are poorly understood. Recent evidence suggests that epigenetic silencing of miRNAs through tumor suppression by CpG island hypermethylation may be a common hallmark of human tumors. Here, we demonstrated that miR-941 was significantly down-regulated in HCC tissues and cell lines and was generally hypermethylated in HCC. The overexpression of miR-941 suppressed in vitro cell proliferation, migration, and invasion and inhibited the metastasis of HCC cells in vivo. Furthermore, the histone demethylase KDM6B (lysine (K)-specific demethylase 6B) was identified as a direct target of miR-941 and was negatively regulated by miR-941. The ectopic expression of KDM6B abrogated the phenotypic changes induced by miR-941 in HCC cells. We demonstrated that miR-941 and KDM6B regulated the epithelial-mesenchymal transition process and affected cell migratory/invasive properties.


Assuntos
Carcinoma Hepatocelular/genética , Metilação de DNA , Histona Desmetilases com o Domínio Jumonji/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Sequência de Bases , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Primers do DNA , Regulação para Baixo , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , RNA Mensageiro/genética
4.
Zhonghua Yi Xue Za Zhi ; 95(38): 3142-6, 2015 Oct 13.
Artigo em Zh | MEDLINE | ID: mdl-26814107

RESUMO

OBJECTIVE: To investigate the effect of antimicrobial peptide cathelicidin secreted by non-tumorous cells in lung tumor growth. METHODS: CRAMP(-/-) mice and WT mice were used to establish a lung cancer model via tail vein injection of Lewis lung carcinoma cells (LLC1). Lung was weighted and tumor number on the lung surface was counted. Kaplan-Meier (K-M) survival curve was used to analyze survival rate of mice. Expression of cathelicidin, Ki-67 and CD68 in the tumor tissue was measured by immunohistochemical analysis. BALF cells were stained with Diff Quik and percentages of leukocyte types were determined by light microscopy. RESULTS: Cathelicidin was high expression in inflammatory cells of tumor tissue, whereas weak expression in tumor cells. The lung weight and number of tumor in CRAMP-/- mice were (0.25±0.04)g and (9.60± 2.25), respectively, which were significantly lower than those of WT mice (0.65±0.05) g and (23.40± 2.68). The difference was statistically significant (t=6.07, 3.95, all P<0.05). And Kaplan-Meier survival analysis showed median survival time of CRAMP-/- mice was 49(46-51)d, which was longer than 34(28-39) d of WT mice (χ2=12.00, P<0.05). And the positive rate of Ki-67 tumor cells was significant reduced from (35.80±2.96)% in WT mice to (18.80±2.38)% in CRAMP-/- groups (t=4.48, P<0.05). The total cell number as well as the number of lymphocytes, neutrophils, and macrophages in BALFs of CRAMP-/- mice were (4.72±0.86)×10(4), (0.08±0.02)×10(4), (0.05±0.02)×10(4) and (4.60±0.84)×10(4), respectively, while of WT mice were (16.18±1.61)×10(4), (0.32±0.05)×10(4), (0.20±0.05)×10(4) and (15.66±1.57)×10(4). All of them had significant difference (t=6.28, 4.39, 3.00, 6.20, all P<0.05). In addition, the infiltration of macrophages into lung tumors was decreased in CRAMP-/- mice compared to WT mice, from (15.53±2.28)/high power field to (6.77±3.12)/high power field (t=3.41, P<0.05). CONCLUSIONS: Non-tumor cells secreted cathelicidin promotes tumor cell proliferation and lung tumor growth. Recruitment of inflammatory cells such as macrophages into the tumor microenvironment may be the main mechanism of action.


Assuntos
Neoplasias Pulmonares , Animais , Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Carcinoma Pulmonar de Lewis , Catelicidinas , Progressão da Doença , Estimativa de Kaplan-Meier , Pulmão , Macrófagos , Camundongos , Neutrófilos
5.
J Neurosci Res ; 92(2): 232-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24327346

RESUMO

We have previously reported that ginkgolides containing ginkgolides A and B (GKAB) reduce infarct size in a rat model of focal ischemia. c-Jun N-terminal kinase (JNK), also known as stress-activated kinase (SAPK), is a critical stress-responsive kinase activated by various brain insults. Previous studies have demonstrated a brief increase in p-SAPK/JNK levels after focal ischemic brain injuries. In this study, we sought to investigate whether the neuroprotective effects of GKAB in rat models of permanent focal cerebral ischemia are associated with the JNK signaling pathway. Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion by intraluminal suture blockade. GKAB was injected intravenously immediately after ischemia onset. Here we demonstrate in rats that GKAB reduces neuronal apoptosis and blocks the increase of p-SAPK/JNK levels and nuclear translocation after cerebral ischemia in a dose-dependent manner. Furthermore, we report that cerebral ischemia increases ischemia-induced induction of reactive oxygen species, and this effect was blocked by GKAB. In addition, we show that BimL is induced and attenuated by GKAB. GKAB also repressed the ischemia-induced increase in the expression of Bax and reversed the decline in expression of Bcl-2. Likewise, there was a reduction in the release or activation of several mitochondrial proapoptotic molecules, including cytochrome c, caspases 3 and 9, and PARP. Taken together, our findings strongly suggest that GKAB-mediated neuroprotective effects against focal ischemia act through the inhibition of p-SAPK/JNK activation, in which the obstruction of the mitochondrial apoptotic pathway via the JNK signaling pathway is a key downstream mechanism of GKAB.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Ginkgolídeos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Western Blotting , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lactonas/farmacologia , Masculino , Mitocôndrias , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio
6.
Hepatology ; 57(2): 667-77, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22996586

RESUMO

UNLABELLED: MicroRNAs (miRNAs) have been reported to be associated with the development of cancers. However, the function of miRNAs in human hepatocellular carcinoma (HCC) remains largely undefined. Here we found that overexpression of miR-10a promoted the migration and invasion of QGY-7703 and HepG2 cells in vitro but suppressed metastasis in vivo. Cell adhesion assays showed that miR-10a suppressed HCC cell-matrix adhesion, which could explain the results of the in vivo animal experiments. The Eph tyrosine kinase receptor, EphA4, was identified as the direct and functional target gene of miR-10a. Knockdown of EphA4 phenocopied the effect of miR-10a and ectopic expression of EphA4 restored the effect of miR-10a on migration, invasion, and adhesion in HCC cells. We further demonstrated that miR-10a and EphA4 regulated the epithelial-mesenchymal transition process and the ß1-integrin pathway to affect cell invasion and adhesion. CONCLUSION: Our findings highlight the importance of miR-10a in regulating the metastatic properties of HCC by directly targeting EphA4 and may provide new insights into the pathogenesis of HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/secundário , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Hepáticas/patologia , MicroRNAs/fisiologia , Metástase Neoplásica/fisiopatologia , Receptor EphA4/metabolismo , Linhagem Celular Tumoral , Junções Célula-Matriz/metabolismo , Feminino , Células Hep G2 , Humanos , Fígado/metabolismo , Masculino , Invasividade Neoplásica , Receptor EphA4/biossíntese
7.
Zhonghua Zhong Liu Za Zhi ; 36(6): 412-7, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25241781

RESUMO

OBJECTIVE: The aim of this study was to investigate the mechanism of cigarette smoking (CS)-induced lung cancer growth in mice. METHODS: RelA/p65⁻/⁻ mice and WT mice were used to establish mouse models of lung cancer. Both mice were divided into two groups: air group and CS group, respectively. Tumor number on the lung surface was counted and maximal tumor size was evaluated using HE staining. Kaplan Meier (K-M) survival curve was used to analyze the survival rate of the mice. Expression of Ki-67, TNF-α and CD68 in the tumor tissue was determined by immunohistochemical analysis, and cyclin D1 and c-myc proteins were examined by Western blot. Apoptosis of tumor cells was analyzed using TUNEL staining. The concentrations of inflammatory cytokines TNF-α, IL-6 and KC in the mouse lung tissues were evaluated by ELISA. RESULTS: Compared with the WT air group, the lung weight, lung tumor multiplicity, as well as maximum tumor size in the WT mice exposed to CS were (1.5 ± 0.1)g, (64.8 ± 4.1) and (7.6 ± 0.2) mm, respectively, significantly increased than those in the WT mice not exposed to CS (P < 0.05 for all). However, there were no statistically significant differences between RelA/p65⁻/⁻ mice before and after CS exposure (P > 0.05 for all). Kaplan-Meier survival analysis showed that CS exposure significantly shortened the life time of WT mice (P < 0.05), and deletion of RelA/p65 in myeloid cells resulted in an increased survival compared with that of the WT mice (P < 0.05 for all). The ratios of Ki-67 positive tumor cells were (43.4 ± 2.9)%, (60.6 ± 5.4)%, (12.8 ± 3.6)% and (15.0 ± 4.2)% in the WT air group, WT CS groups, RelA/p65⁻/⁻ air groups and RelA/p65⁻/⁻ CS groups, respectively. After smoking, the number of Ki-67-positive cells was significantly increased in the WT mice (P < 0.05). However, there was no significant difference between the RelA/p65⁻/⁻ groups before and after smoking (P > 0.05). The apoptosis rate of WT air, WT CS, RelA/p65⁻/⁻ air and RelA/p65⁻/⁻ CS groups were (11.6 ± 1.7)%, (13.0 ± 2.0)%, (13.2 ± 2.0)% and (11.0 ± 1.4)%, respectively, with no significant difference among them (P > 0.05). Expression of cyclin D1 and c-myc was induced in response to CS exposure in lung tumor cells of WT mice. In contrast, their expressions were not significantly changed in the RelA/p65⁻/⁻ mice after smoke exposure. CS exposure was associated with an increased number of macrophages infiltrating in the tumor tissue, in both WT and RelA/p65⁻/⁻ mice (P < 0.05). The concentrations of IL-6, KC and TNF-α were significantly increased after CS exposure in the lungs of WT mice (P < 0.05). CONCLUSIONS: Cigarette smoking promotes the lung cancer growth in mice. Myeloid cell RelA/p65 mediates CS-induced tumor growth. TNFα regulated by RelA/p65 may be involved in the lung cancer development.


Assuntos
Neoplasias Pulmonares/induzido quimicamente , Fator de Transcrição RelA/metabolismo , Animais , Citocinas , Interleucina-6/metabolismo , Pulmão/metabolismo , Macrófagos , Masculino , Camundongos , Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fumar/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo
8.
Mitochondrial DNA B Resour ; 9(5): 647-651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770144

RESUMO

Hydrocotyle vulgaris is a perennial wetland clonal plant in the Araliaceae family, which was introduced to China as an ornamental plant in the 1990s. Although H. vulgaris is now considered a potential invasiveness species in China, it also plays a significant role in the remediation of water pollution. Here, we reported its complete chloroplast genome and analyzed the basic characteristics. The chloroplast genome was 153,165 bp in length, including a pair of inverted repeat (IR) regions of 25,072 bp separated by a large single-copy (LSC) region of 84,291 bp and a small single-copy (SSC) region of 18,730 bp. The H. vulgaris chloroplast genome contained 132 predicted genes, and its overall GC content was 37.60%. Phylogenetic analysis revealed that H. vulgaris was closely related to H. verticillata. The H. vulgaris chloroplast genome presented in this study will lay a foundation for further genetic and genomic studies of the genus Hydrocotyle.

9.
Mitochondrial DNA B Resour ; 9(6): 787-792, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903543

RESUMO

Bassia scoparia, an annual potherb belonging to the family Amaranthaceae, has been widely used in traditional Chinese and Japanese medicine for over 2000 years. Herein, we presented its complete chloroplast. The chloroplast genome sequence was 151,278 bp in length with a 36.6% content of GC. The genome showed the typical quadripartite structure, comprising a pair of inverted repeat (IR) regions (24,353 bp) separated by a large single-copy (LSC) region (84,067 bp) and a small single-copy (SSC) region (18,505 bp). This chloroplast genome harbored 133 predicted genes, including 88 protein-coding genes, 37 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The phylogenetic analysis indicated that B. scoparia was closely related to B. littorea. This newly sequenced chloroplast genome not only enhances our understanding of the genome of Bassia but also provides valuable insights for the evolutionary study of the family Amaranthaceae.

10.
J Biol Chem ; 287(17): 14301-9, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22399294

RESUMO

MicroRNAs are a class of small noncoding RNAs that function as key regulators of gene expression at the post-transcriptional level. In this study, we demonstrate that miR-214 is frequently down-regulated in cervical cancer, and its expression reduces the proliferation, migration, and invasiveness of cervical cancer cells, whereas inhibiting its expression results in enhanced proliferation, migration, and invasion. miR-214 binds to the 3'-UTR of UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 7 (GALNT7), thereby repressing GALNT7 expression. Furthermore, we are the first to show, using quantitative real-time PCR, that GALNT7 is frequently up-regulated in cervical cancer. The knockdown of GALNT7 markedly inhibits cervical cancer cell proliferation, migration, and invasion, whereas ectopic expression of GALNT7 significantly enhances these properties, indicating that GALNT7 might function as an oncogene in cervical cancer. The restoration of GALNT7 expression can counteract the effect of miR-214 on cell proliferation, migration, and invasiveness of cervical cancer cells. Together, these results indicate that miR-214 is a new regulator of GALNT7, and both miR-214 and GALNT7 play important roles in the pathogenesis of cervical cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , N-Acetilgalactosaminiltransferases/química , Uridina Difosfato N-Acetilgalactosamina/química , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Sequência de Bases , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Feminino , Células HeLa , Humanos , MicroRNAs/metabolismo , Microscopia de Fluorescência/métodos , Dados de Sequência Molecular , N-Acetilgalactosaminiltransferases/metabolismo , Peptídeos/química , Homologia de Sequência do Ácido Nucleico
11.
Zhonghua Zhong Liu Za Zhi ; 35(9): 660-5, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24332052

RESUMO

OBJECTIVE: The aim of this study was to investigate the role of macrophages in promotion of ovarian tumor cell proliferation mediated by over-expression of antimicrobial peptide LL-37. METHODS: To co-culture ovarian tumor cells SKOV3, 3AO and HO-8910 with macrophages. The Transwell(®) inserts system was used in the co-culture model. The effect of macrophages promoted ovarian tumor cell proliferation was assessed by BrdU-ELISA and cell number counting. Expressions of mRNA and protein of LL-37 in the macrophages and SKOV3 cells were determined by RT-PCR and Western blot analysis. To observe that LL-37 is responsible for macrophage-promoted ovarian tumor cells growth, LL-37 neutralizing antibody was added to abrogate the LL-37 activation. RESULTS: The cell number assay showed that after 4 days coincubation with macrophages in the proportion of 1:0.5, the number of SKOV3 cells increased from (6.0 ± 0.5)×10(4) to (11.8 ± 1.3)×10(4), showing a significant difference (P < 0.05). It also showed that the growth of the SKOV3 cells was dependent on the macrophage number (P < 0.05). The number variability of 3AO and HO-8910 cells was as the same as SKOV3 cells upon co-culture with macrophages. As determined by BrdU-ELISA, the resulted proliferation of ovarian tumor cells was similar to the result of cell number counting. RT-PCR and Western blot results showed that the expression of LL-37 mRNA and protein in the macrophages was remarkably enhanced in a time dependent manner upon coincubation with SKOV3 cells, but did not work in SKOV3 cells. BrdU-ELISA assay exhibited that treatment of cells with LL-37 significantly stimulated HO-8910 and 3AO cell proliferation. Addition of LL-37 neutralizing antibody markedly inhibited macrophage-promoted ovarian tumor cell (SKOV3, 3AO and HO-8910 cells) proliferation. The OD values of these three cells were decreased from 2.95 ± 0.11 to 1.45 ± 0.04, from 3.39 ± 0.36 to 1.32 ± 0.09 and from 3.93 ± 0.17 to 1.68 ± 0.23, respectively (P < 0.05). CONCLUSIONS: Over-expression and release of LL-37 from macrophages is responsible for proliferation of ovarian tumor cells in co-culture condition. The data presented indicate that LL-37 may be critical for macrophage-induced tumor progression.


Assuntos
Proliferação de Células , Macrófagos/fisiologia , Neoplasias Ovarianas/patologia , Anticorpos Neutralizantes/farmacologia , Peptídeos Catiônicos Antimicrobianos , Catelicidinas/genética , Catelicidinas/metabolismo , Catelicidinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Feminino , Humanos , Macrófagos/citologia , Neoplasias Ovarianas/metabolismo , RNA Mensageiro/metabolismo
12.
ISA Trans ; 124: 318-325, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33153706

RESUMO

The problem of sliding mode control (SMC) for a class of Markov jump systems (MJSs) is addressed in this paper based on a resource-aware triggering mechanism which realizes computational resources saving and disturbance attenuation simultaneously. By introducing the self-triggered policy, the next execution time is pre-computed for sampling, updating and executing by relying on the latest sampled information. Then, the switching surface and the related dynamics of the original MJSs are obtained by means of a self-triggered sampling scheme. To guarantee both the system stability and the desired disturbance attenuation performance, sufficient conditions are presented in terms of linear matrix inequalities. Moreover, to ensure the time finiteness of the predefined switching surface reachability and satisfy the desirable sliding motion performance, an SMC law is proposed. The validity and superiority of the developed scheme are demonstrated via a simulation example.

13.
Mol Cancer ; 9: 16, 2010 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-20102618

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are a new class of naturally occurring, small, non-coding RNAs that regulate protein-coding mRNAs by causing mRNA degradation or repressing translation. The roles of miRNAs in lineage determination and proliferation, as well as the localization of several miRNA genes at sites of translocation breakpoints or deletions, have led to speculation that miRNAs could be important factors in the development or maintenance of the neoplastic state. RESULTS: We showed that miR-9 was downregulated in human gastric adenocarcinoma. Overexpression of miR-9 suppressed the growth of human gastric adenocarcinoma cell line MGC803 cell as well as xenograft tumors derived from them in SCID mice. Bioinformatics analysis indicated a putative miR-9 binding site in the 3'-untranslated region (3'UTR) of the tumor-related gene NF-kappaB1 mRNA. In an EGFP reporter system, overexpression of miR-9 downregulated EGFP intensity, and mutation of the miR-9 binding site abolished the effect of miR-9 on EGFP intensity. Furthermore, both the NF-kappaB1 mRNA and protein levels were affected by miR-9. Finally, knockdown of NF-kappaB1 inhibited MGC803 cell growth in a time-dependent manner, while ectopic expression of NF-kappaB1 could rescue MGC803 cell from growth inhibition caused by miR-9. CONCLUSION: These findings indicate that miR-9 targets NF-kappaB1 and regulates gastric cancer cell growth, suggesting that miR-9 shows tumor suppressive activity in human gastric cancer pathogenesis.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , NF-kappa B/genética , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , MicroRNAs/metabolismo , Dados de Sequência Molecular , NF-kappa B/metabolismo , Neoplasias Gástricas/patologia , Transcrição Gênica , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Nanosci Nanotechnol ; 10(8): 5089-92, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21125854

RESUMO

We describe an approach to synthesize monodisperse CoPt nanoparticles with dendrimer as template by a simple chemical reduction method in aqueous solution using NaBH4 as reducing agent at room temperature. The as-made CoPt nanoparticles buried in the dendrimer matrix have the chemically disordered fcc structure and can be transformed to the fct phase after annealing at 700 degrees C. This is the first report of dendrimer-mediated room temperature synthesis of monodisperse magnetic nanoparticles in aqueous solution.

15.
Oncotarget ; 7(20): 29011-22, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27049722

RESUMO

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor which has been implicated in numerous solid and hematologic cancers. ALK mutations are reported in about 5-7% of neuroblastoma cases but the ALK-positive percentage increases significantly in the relapsed patient population. Crizotinib, the first clinically approved ALK inhibitor for the treatment of ALK-positive lung cancer has had less dramatic responses in neuroblastoma. Here we investigate the efficacy of a second-generation ALK inhibitor, brigatinib, in a neuroblastoma setting. Employing neuroblastoma cell lines, mouse xenograft and Drosophila melanogaster model systems expressing different constitutively active ALK variants, we show clear and efficient inhibition of ALK activity by brigatinib. Similar abrogation of ALK activity was observed in vitro employing a set of different constitutively active ALK variants in biochemical assays. These results suggest that brigatinib is an effective inhibitor of ALK kinase activity in ALK addicted neuroblastoma that should be considered as a potential future therapeutic option for ALK-positive neuroblastoma patients alone or in combination with other treatments.


Assuntos
Antineoplásicos/farmacologia , Neuroblastoma/patologia , Compostos Organofosforados/farmacologia , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Quinase do Linfoma Anaplásico , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Drosophila , Inibidores Enzimáticos/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neuroblastoma/enzimologia , Neuroblastoma/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Oncotarget ; 6(33): 34924-40, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26472185

RESUMO

The altered expression of miRNAs in response to stresses contributes to cancer pathogenesis. However, little is known regarding the mechanism by which cellular stresses drive alterations in miRNA expression. Here, we found that serum starvation enhanced mitophagy by downregulating the mitophagy-associated protein voltage-dependent anion channel 1 (VDAC1) and by inducing the expression of miR-320a and the transcription factor cAMP responsive element binding protein 1(CREB1). Furthermore, we cloned the promoter of miR-320a and identified the core promoter of miR-320a in the upstream -16 to -130 region of pre-miR-320a. Moreover, CREB1 was found to bind to the promoter of miR-320a to activate its expression and to induce mitophagy during serum starvation. Collectively, our results reveal a new mechanism underlying serum starvation-induced mitophagy in which serum starvation induces CREB1 expression, in turn activating miR-320a expression, which then down-regulates VDAC1 expression to facilitate mitophagy. These findings may provide new insights into cancer cell survival in response to environmental stresses.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Regulação Neoplásica da Expressão Gênica/fisiologia , MicroRNAs/biossíntese , Neoplasias do Colo do Útero/patologia , Canal de Ânion 1 Dependente de Voltagem/biossíntese , Western Blotting , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Regulação para Baixo , Feminino , Humanos , Mitofagia/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Neoplasias do Colo do Útero/metabolismo
20.
Sci Rep ; 5: 15793, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26507454

RESUMO

miRNAs typically downregulate the expression of target genes by binding to their 3'UTR, and dysregulation of miRNAs may contribute to tumorigenesis. Here, we found that miR-346 and miR-138 competitively bind to a common region in the 3'UTR of hTERT mRNA and have opposite effects on the expression and function of hTERT in human cervical cancer cells. Furthermore, G-rich RNA sequence binding factor 1 (GRSF1) mediates the miR-346-dependent upregulation of hTERT by binding to the miR-346 middle sequence motif (CCGCAU) which forms a "bulge loop" when miR-346 is bound to the hTERT 3'UTR, facilitating the recruitment of hTERT mRNA to ribosomes to promote translation in an AGO2-independent manner. Conversely, miR-138 suppresses hTERT expression in an AGO2-dependent manner. Interestingly, replacement of the miR-138 middle sequence with that of miR-346 results in an upregulation of hTERT expression in a GRSF1-dependent manner. Moreover, miR-346 depends on GRSF1 to upregulate another target gene, activin A receptor, type IIB (ACVR2B), in which miR-346 "CCGCAU" motif is essential. These findings reveal novel mechanisms of miRNA-mediated upregulation of target gene expression and describe the coordinated action of multiple miRNAs to control the fate of a single target mRNA through binding to its 3'UTR.


Assuntos
Proteínas Argonautas/genética , MicroRNAs/genética , Proteínas de Ligação a Poli(A)/genética , Telomerase/genética , Regiões 3' não Traduzidas/genética , Animais , Linhagem Celular Tumoral , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus
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