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1.
Proc Natl Acad Sci U S A ; 120(40): e2304096120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748052

RESUMO

Eight extant species of pangolins are currently recognized. Recent studies found that two mitochondrial haplotypes identified in confiscations in Hong Kong could not be assigned to any known pangolin species, implying the existence of a species. Here, we report that two additional mitochondrial haplotypes identified in independent confiscations from Yunnan align with the putative species haplotypes supporting the existence of this mysterious species/population. To verify the new species scenario we performed a comprehensive analysis of scale characteristics and 138 whole genomes representing all recognized pangolin species and the cryptic new species, 98 of which were generated here. Our morphometric results clearly attributed this cryptic species to Asian pangolins (Manis sp.) and the genomic data provide robust and compelling evidence that it is a pangolin species distinct from those recognized previously, which separated from the Philippine pangolin and Malayan pangolin over 5 Mya. Our study provides a solid genomic basis for its formal recognition as the ninth pangolin species or the fifth Asian one, supporting a new taxonomic classification of pangolins. The effects of glacial climate changes and recent anthropogenic activities driven by illegal trade are inferred to have caused its population decline with the genomic signatures showing low genetic diversity, a high level of inbreeding, and high genetic load. Our finding greatly expands current knowledge of pangolin diversity and evolution and has vital implications for conservation efforts to prevent the extinction of this enigmatic and endangered species from the wild.


Assuntos
Genômica , Pangolins , Animais , Efeitos Antropogênicos , Ásia , China , Pangolins/genética , Crescimento Demográfico
2.
Phys Chem Chem Phys ; 24(9): 5690-5699, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35187550

RESUMO

To combine both electride and alkalide characteristics in one molecular switch, it is shown herein that the phenalenyl radical and the M3 ring (M3-PHY, M = Li, Na, and K) stacked with parallel and vertical geometries are good candidates. The former geometry is the superalkali electride e-⋯M3+-PHY while the latter geometry is the superalkalide Mδ--M2(1-δ)+-PHY-. The superalkalide Mδ--M2(1-δ)+-PHY- may isomerize to the superalkali electride e-⋯M3+-PHY (M = Li, Na, and K) using suitable long-wavelength irradiation, while the latter may isomerize to the former with suitable short-wavelength irradiation. Also, applying suitable oriented external electric fields can drive the superalkalide Mδ-M2(1-δ)+-PHY- to change into the superalkali electride e-⋯M3+-PHY (M = Li, Na, and K). The differences in the static and dynamic first hyperpolarizability (ß0) values between them were also studied.

3.
J Proteome Res ; 12(6): 2422-38, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23607740

RESUMO

Sexual dimorphism is initialed by the components of the sex determination pathway and is most evident in gonads and germ cells. Although striking dimorphic expressions have been detected at the transcriptional level between the silkworm larval testis and the ovary, the sex-dimorphic expressions at the protein level have not yet been well characterized. The proteome of silkworm larval gonads was investigated using a shotgun-based identification. A total of 286 and 205 nonredundant proteins were identified from the silkworm testis and ovary, respectively, with a false discovery rate (FDR) lower than 1%. Only 40 and 16 proteins were previously identified, and 246 and 189 proteins were newly identified in the silkworm testis and the ovary, respectively. The gametogenesis mechanism of silkworm was demonstrated using the protein expression profile and bioinformatics analysis. Cellular retinoic acid binding protein (CRABP) showed to be highly abundant in testis, while tubulins were abundant in ovary. Several homologies of Drosophila essential proteins for gametogenesis were identified in silkworm, such as male meiotic arrest gene product ALY and VISMAY in testis, and maternal mRNA localization protein exuperantia and SQUID in ovary. The gene ontology (GO) annotation and pathway analysis provide system-level insights into the sexual dimorphism and gametogenesis.


Assuntos
Bombyx/genética , Gametogênese/genética , Proteínas de Insetos/isolamento & purificação , Ovário/química , Proteoma/isolamento & purificação , Testículo/química , Animais , Mapeamento Cromossômico , Cromossomos de Insetos/química , Drosophila melanogaster/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/genética , Larva/genética , Masculino , Anotação de Sequência Molecular , Proteoma/química , Proteoma/genética , Homologia de Sequência de Aminoácidos , Caracteres Sexuais
4.
Front Surg ; 9: 985168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684155

RESUMO

Background: This study aimed to investigate whether visceral adipose tissue index (VATI) is a significant risk factor for the early recurrence (ER) of HBV-related hepatocellular carcinoma (HCC) (≤5 cm) after hepatectomy. Methods: The recruited cohort patients who were positive for hepatitis B virus, presented with surgically confirmed HCC (≤5 cm) from Army Medical University (internal training cohort: n = 192) and Chongqing Medical University (external validation group: n = 46). We measured VATI, subcutaneous adipose tissue index (SATI) via computed tomography (CT). ER was defined as recurrence within 2 years after hepatectomy. The impact of parameters on outcome after hepatectomy for HCC was analyzed. Results: Univariate analysis showed that alpha-fetoprotein levels (p = 0.044), body mass index (BMI) (p < 0.001), SATI (p < 0.001), and VATI (p < 0.001) were significantly different between ER and non-ER groups in internal training cohort. Multivariate analysis identified VATI as an independent risk factor for ER (odds ratio = 1.07, 95% confidence interval: 1.047-1.094, p < 0.001), with a AUC of 0.802, based on the cut-off value of VATI, which was divided into high risk (≥37.45 cm2/m2) and low risk (<37.45 cm2/m2) groups. The prognosis of low risk group was significantly higher than that of high risk group (p < 0.001). The AUC value of VATI in external validation group was 0.854. Conclusion: VATI was an independent risk factor for the ER, and higher VATI was closely related to poor outcomes after hepatectomy for HBV-related HCC (≤5 cm).

5.
J Proteome Res ; 10(8): 3551-64, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21657221

RESUMO

The posterior silk gland (PSG) is the most important suborgan responsible for the synthesis and secretion of silk core fibroin proteins in silkworm. Here, we performed genome-scale expression profiling analysis of silkworm PSG at the fourth molting (M4) and at day 1 (V1), day 3 (V3), day 5 (V5), and wandering stage (W) of the fifth instar by microarray analysis with 22 987 probes. We found that the five genes of silk proteins secreted from PSG including fibroin heavy (H) and light (L) chains, P25, seroin 1, and seroin 2 basically showed obvious up-regulation at V3 which lasted to V5, while slight down-regulation at W. The expression of translation-related genes including ribosomal proteins and translation initiation factors generally remained stable from M4 to V5, whereas it showed clear down-regulation at W. Clustering analysis of the 643 significantly differentially expressed transcripts revealed that 43 of the important genes including seroin 1 and sugar transporter protein had co-expression patterns which were consistent with the rate changes of fibroin synthesis and PSG growth. Pathway analysis disclosed that the genes in different clusters might have co-regulations and direct interactions. These genes were supposed to be involved in the fibroin synthesis and secretion. The differential expression of several hormone-related genes also suggested their functions on the regulation of PSG development and fibroin synthesis. 2D gel-based proteomics and phosphoproteomics profiling revealed that the phosphorylated proteins accounted for no more than one-sixth of the total proteins at each stage, which was much lower than the level in normal eukaryotic cells. Changes in the phosphorylation status and levels of several proteins such as actin-depolymerizing factor 1 and enolase might be deeply involved in fibroin secretion and tissue development. Shotgun proteomic profiling combined with label-free quantification analysis on the PSG at V3, V5, and W revealed that many small heat shock proteins (sHSP) were specially expressed at W, which was substantially consistent with the results from 2-DE analysis, and implied the close correlations of sHSP with the physiological states of PSG at W. A majority of significantly up-regulated proteins at V5 were related to ribosome pathway, which was different from the microarray results, implying that the translation-level regulation of ribosomal proteins might be critical for fibroin synthesis. In contrast, the ubiquitin-proteasome pathway related proteins appeared obviously up-regulated at W, suggesting that the programmed cell death process of PSG cells might be started before cocooning.


Assuntos
Bombyx/metabolismo , Fibroínas/biossíntese , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Insetos/biossíntese , Animais , Bombyx/genética , Cromatografia Líquida , Análise por Conglomerados , Eletroforese em Gel Bidimensional , Análise de Sequência com Séries de Oligonucleotídeos , Proteômica , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
6.
Cell Res ; 31(8): 836-846, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34135479

RESUMO

Severe COVID-19 disease caused by SARS-CoV-2 is frequently accompanied by dysfunction of the lungs and extrapulmonary organs. However, the organotropism of SARS-CoV-2 and the port of virus entry for systemic dissemination remain largely unknown. We profiled 26 COVID-19 autopsy cases from four cohorts in Wuhan, China, and determined the systemic distribution of SARS-CoV-2. SARS-CoV-2 was detected in the lungs and multiple extrapulmonary organs of critically ill COVID-19 patients up to 67 days after symptom onset. Based on organotropism and pathological features of the patients, COVID-19 was divided into viral intrapulmonary and systemic subtypes. In patients with systemic viral distribution, SARS-CoV-2 was detected in monocytes, macrophages, and vascular endothelia at blood-air barrier, blood-testis barrier, and filtration barrier. Critically ill patients with long disease duration showed decreased pulmonary cell proliferation, reduced viral RNA, and marked fibrosis in the lungs. Permanent SARS-CoV-2 presence and tissue injuries in the lungs and extrapulmonary organs suggest direct viral invasion as a mechanism of pathogenicity in critically ill patients. SARS-CoV-2 may hijack monocytes, macrophages, and vascular endothelia at physiological barriers as the ports of entry for systemic dissemination. Our study thus delineates systemic pathological features of SARS-CoV-2 infection, which sheds light on the development of novel COVID-19 treatment.


Assuntos
COVID-19/patologia , Pulmão/virologia , SARS-CoV-2/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Autopsia , COVID-19/virologia , China , Estudos de Coortes , Estado Terminal , Feminino , Fibrose , Hospitalização , Humanos , Rim/patologia , Rim/virologia , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/virologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/metabolismo , SARS-CoV-2/genética , Baço/patologia , Baço/virologia , Traqueia/patologia , Traqueia/virologia
7.
Sci Transl Med ; 12(531)2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075946

RESUMO

MYCN-amplified neuroblastoma (NB) is characterized by poor prognosis, and directly targeting MYCN has proven challenging. Here, we showed that aldehyde dehydrogenase family 18 member A1 (ALDH18A1) exerts profound impacts on the proliferation, self-renewal, and tumorigenicity of NB cells and is a potential risk factor in patients with NB, especially those with MYCN amplification. Mechanistic studies revealed that ALDH18A1 could both transcriptionally and posttranscriptionally regulate MYCN expression, with MYCN reciprocally transactivating ALDH18A1 and thus forming a positive feedback loop. Using molecular docking and screening, we identified an ALDH18A1-specific inhibitor, YG1702, and demonstrated that pharmacological inhibition of ALDH18A1 was sufficient to induce a less proliferative phenotype and confer tumor regression and prolonged survival in NB xenograft models, providing therapeutic insights into the disruption of this reciprocal regulatory loop in MYCN-amplified NB.


Assuntos
Aldeído Desidrogenase/genética , Proteína Proto-Oncogênica N-Myc , Células-Tronco Neurais , Neuroblastoma , Linhagem Celular Tumoral , Retroalimentação , Humanos , Simulação de Acoplamento Molecular , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética
8.
Biochem Biophys Res Commun ; 381(3): 448-52, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19233142

RESUMO

G-protein-coupled formylpeptide receptor (FPR) has recently been found to be functionally expressed in gliomas and are probably involved in their malignant biological behavior. In an attempt to explore the therapeutic significance of FPRs, we used wild-type human glioblastoma cells (U87), the corresponding FPR short-interfering RNA transfected (siRNA U87) cells, and mock-transfected U87 cells (mock U87) to establish xenografts in mice brains. Compared to wild-type and mock transfected cells, siRNA U87 cells formed smaller and more well-differentiated xenografts with fewer mitotic figures and more glial filaments within their cytoplasm. The density of microvessels, which presented as a nearly normal morphous, was also decreased significantly in FPR knockdown cells. Moreover, fewer invasive foci could be observed in the xenografts derived from siRNA U87 cells, which also showed a poor migratory capacity in vitro. We suggest that decreased VEGF and MMP-2/-9 expression might be a possible mechanism for the decreasing angiogenic potential and invasive capability of U87 cells after FPR knockdown. Functional FPR might be essential for sustaining the growth and aggressive phenotype of gliomas, and could therefore be a potential therapeutic target.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Glioma/irrigação sanguínea , Glioma/patologia , Receptores de Formil Peptídeo/genética , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Glioma/metabolismo , Humanos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Microvasos , Invasividade Neoplásica , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Interferência de RNA , Receptores de Formil Peptídeo/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Neurooncol ; 93(2): 165-74, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19052696

RESUMO

Endothelial progenitor cells (EPCs) are important initiators of vasculogenesis in the process of tumor neovascularization. However, it is unclear how circulating EPCs contribute to the formation of tumor microvessels. In this study, we isolated CD34(+)/CD133(+) cells from human umbilical cord blood (HUCB) and obtained EPCs with the capacities of forming colonies, uptaking acetylated low-density lipoprotein (ac-LDL), binding lectins and expressing vascular endothelial growth factor (VEGF) receptor 2 (VEGFR-2, KDR), CD31 and von Willebrand factor (vWF). These EPCs were actively proliferative and migratory, and could formed capillary-like tubules in response to VEGF. When injected into mice bearing subcutaneously implanted human malignant glioma, EPCs specifically accumulated at the sites of tumors and differentiated into mature endothelial cells (ECs), which accounted for 18% ECs of the tumor microvessels. The incorporation of circulating EPCs into tumor vessel walls significantly affected the morphology and structure of the vasculature. Our results suggest that circulating EPCs constitute important components of tumor microvessel network and contribute to tumor microvascular architecture phenotype heterogeneity.


Assuntos
Células Endoteliais/citologia , Endotélio Vascular/patologia , Glioblastoma/patologia , Transplante de Neoplasias/patologia , Neovascularização Patológica/patologia , Células-Tronco/citologia , Transplante Heterólogo/patologia , Animais , Antígenos CD/análise , Antígenos CD34/análise , Adesão Celular , Divisão Celular , Células Endoteliais/imunologia , Células Endoteliais/patologia , Sangue Fetal/citologia , Citometria de Fluxo , Humanos , Camundongos , Camundongos SCID , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Receptores OX40/análise , Células-Tronco/imunologia , Células-Tronco/patologia
10.
Int J Clin Exp Pathol ; 12(4): 1399-1405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31933955

RESUMO

Hepatic monotypic epithelioid angiomyolipoma (AML) is a rare lesion in which the predominant population of an epithelioid component can mimic hepatocellular carcinoma (HCC). The hepatic epithelioid AML with concomitant HCC is extremely uncommon. In this study, we present the clinical and pathologic features of a case of hepatic monotypic epithelioid AML with concomitant HCC in a 63-year-old man. Imaging examinations revealed two masses located in the liver, measuring 83×63 mm and 37×27 mm separately, which exhibited an early contrast enhancement and a rapid washout on enhanced computed tomography (CT), so that HCC with intrahepatic metastases was suspected. The small tumor was removed for intraoperative frozen section examination. Grossly, the tumor was solitary, well-circumscribed, and non-encapsulated. Microscopically, it was composed purely of a trabecular arrangement of epithelioid cells with a sinusoidal pattern. Immunohistochemically, it was positive for HMB45, Melan-A, and alpha smooth muscle actin (α-SMA). Interestingly, the large tumor has the histologic features similar to those of the small one. However, it was positive for epithelioid markers and negative for the melanocytic markers. It reminds us that there is a possibility of coexistence of HAML and HCC in the liver. We believe that this might be the first case report of a hepatic monotypic epithelioid AML with concomitant HCC. The patient gave up treatment and died in 6 months after the operation in the follow-up.

11.
Yao Xue Xue Bao ; 43(2): 133-7, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18507338

RESUMO

This study is to investigate whether the synthesized chiral compound Nordy has influence on the function of endothelial progenitor cells (EPCs) from human umbilical cord blood induced by vascular endothelial growth factor (VEGF). EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After cultured for 7 -10 days, EPCs were prepared for detecting effect of Nordy on proliferation, migration and tubule-forming activity in Matrigel induced by VEGF. Incubation of EPCs with 100 micromol L(-1) Nordy for 24 h initially inhibited the proliferative capacity of EPCs induced by VEGF (P <0.05). Moreover, 25 -50 micromol L(-1) Nordy also exhibited inhibitory effect at 48 -72 h. In addition, 25 - 100 micromol L(-1) Nordy impaired EPCs migratory and tubule-forming capacity in vitro (P < 0.05). Nordy could inhibit in EPCs the functions of proliferation, migration and tubulogenesis induced by VEGF in vitro, which might be a possible mechanism of its anti-EPCs effects.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Masoprocol/análogos & derivados , Neovascularização Fisiológica/efeitos dos fármacos , Células-Tronco/citologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , Sangue Fetal/citologia , Humanos , Masoprocol/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
12.
Zhonghua Bing Li Xue Za Zhi ; 37(1): 45-50, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18509985

RESUMO

OBJECTIVE: To investigate vasculogenic potential of endothelial progenitor cells (EPCs) derived from human umbilical cord blood and their contribution to the neovascularization of malignant glioma in vivo. METHODS: EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After 7-10 days of culture, EPCs were investigated for CD34 and VEGFR-2 expression by direct immunofluoresent staining. The proliferative activity, migratory capability and forming capillary-like tubules were also monitored after stimulation with VEGF(50 mg/L) in vitro. Moreover, EPCs were administered into tumor-bearing mice, and the tumor and mouse organs were examined under confocal laser scanning microscope to visualize the distribution and localization of transplanted EPCs. In order to quantity the incorporation of EPCs into tumor vessels, cryosections of the tumor tissue were double-labelled with antihuman CD31 and anti-mouse CD31. RESULTS: After 7 to 10 days of culture, EPCs assumed cobblestone-like monolayer growth pattern with nearly complete confluence, and expressed CD34 and VEGFR-2. Significant proliferative activity, increased migratory capability and forming capillary-like tubules were observed when stimulated with VEGF. The transplanted EPCs in vivo specifically homed to solid tumor tissue and incorporated into the tumor's endothelium. Quantitative analysis revealed that human EPCs contributed significantly to tumor neovascularization by incorporation into tumor vasculature (18.68 +/- 1.32)% of the total vessels. CONCLUSION: EPCs possess the potential to form neovascular network in tumor and play a role in the phenotypical heterogeneity of tumor microvascular architecture.


Assuntos
Células Endoteliais/patologia , Endotélio Vascular/patologia , Glioma/complicações , Neovascularização Patológica/etiologia , Células-Tronco/patologia , Animais , Antígenos CD34/imunologia , Células Endoteliais/fisiologia , Endotélio Vascular/fisiopatologia , Sangue Fetal/citologia , Glioma/patologia , Humanos , Camundongos , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/imunologia , Células-Tronco/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia
13.
Wei Sheng Wu Xue Bao ; 45(4): 610-3, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16245882

RESUMO

Based on the full length cDNA clone of a Cucumber mosaic virus satellite RNA, which was 369nt in size, artificial mutants were developed by the method of error-prone PCR and DNA shuffling. The new satellite cDNAs were transcribed in vitro into ssRNA and pseudo-recombined with a helper Cucumber mosaic virus, which contains no satellite RNA. Sequence analysis showed that A to T/G or G to A replacement all the four mutants, named MS1, MS5, MS6 and MS11 respectively, and there is no C to G or G to C replacement, but amongst, only the mutants MS11 could replicated when recombined with the helper virus strain. No satellite RNA could be detected by RT-PCR amplification and double-stranded RNA analysis for those pseudo-recombination constitution of Cucumber mosaic virus strain with mutants MS1, MS5 and MS6.Sequence homological comparison showed that the single replacement of mutants MS1, MS5 and MS6 occurred in the highly conservative regions and the T to A replacement of mutant MS11 was located in the normal-variation region. This is the first artificial mutation of satellite RNA of plant RNA viruses. The results indicated that single base in the region of satellite RNA maybe important to maintaining the biological activity of satellite RNA for its replication and stability. The variation and evolution of satellite RNA could be hopefully studied through combination directed evolution by DNA shuffling with pseudo-recombination in vitro.


Assuntos
Satélite do Vírus do Mosaico do Pepino/genética , Mutação , Satélite do Vírus do Mosaico do Pepino/química , Satélite do Vírus do Mosaico do Pepino/fisiologia , Reação em Cadeia da Polimerase
14.
ACS Appl Mater Interfaces ; 7(51): 28156-65, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26647284

RESUMO

A series of fluorene derivatives end-capped with diphenylamino and oxadiazolyl were synthesized, and their photophysical and electrochemical properties are reported. Aggregation-induced emission (AIE) effects were observed for the materials, and bipolar characteristics of the molecules are favored with measurement of carrier mobility and calculation of molecular orbitals using density functional theory (DFT). Using the fluorene derivatives as emitting-layer, nondoped organic light-emitting devices (OLEDs) have been fabricated by spin-coating in the configuration ITO/PEDOT:PSS(35 nm)/PVK(15 nm)/PhN-OF(n)-Oxa(80 nm)/SPPO13(30 nm)/Ca(8 nm)/Al(100 nm) (n = 2-4). The best device with PhN-OF(2)-Oxa exhibits a maximum luminance of 14 747 cd/m(2), a maximum current efficiency of 4.61 cd/A, and an external quantum efficiency (EQE) of 3.09% in the blue region. Investigation of the correlation between structures and properties indicates that there is no intramolecular charge transfer (ICT) increase in these molecules with the increase of conjugation length. The device using material of the shortest conjugation length as emitting-layer gives the best electroluminescent (EL) performances in this series of oligofluorenes.

16.
Clin Cancer Res ; 21(17): 4004-13, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26023083

RESUMO

PURPOSE: To identify the miRNA regulators of C-X-C motif chemokine receptor 4 (CXCR4) and the underlying mechanism as well as the therapeutic and prognostic values in human glioblastoma (GBM). EXPERIMENTAL DESIGN: miRNA profile analyses and bioinformatics predictions were used to identify the mediators of CXCR4, which were confirmed by luciferase reporter assay, Western blot assay and immunohistochemistry. The effects of miR-663 on CXCR4-mediated GBM malignancy were investigated by gain-of-function experiments. Orthotopic xenografts derived from constitutive or induced miR-663-expressing GBM cells were used to determine the antitumor effects of miR-663 and CXCR4-specific antagonist AMD3100. Bivariate correlation analyses were used to examine the correlation of miR-663 and CXCR4 levels in glioma. The prognostic values of miR-663 and CXCR4 were examined in 281 cases of astrocytic glioma from our hospital and 476 cases of GBM from The Cancer Genome Atlas database using the multivariate Cox regression analysis and Kaplan-Meier analysis. RESULTS: miR-663 negatively regulated CXCR4 expression by targeting its coding sequence in GBM and compromised the proliferative and invasive capacities of GBM cells induced by CXCR4 overexpression. Constitutive or induced miR-663 overexpression combined with CXCR4 antagonist AMD3100 suppressed orthotopic GBM growth and prolonged tumor-bearing mice survival. Clinically, miR-663 and CXCR4 were inversely correlated in GBM and composed a valuable biomarker set in predicting the outcomes of GBM patients. CONCLUSIONS: miR-663 negatively regulated CXCR4 to inhibit its oncogenic effect. Combination of miR-663 and CXCR4 can serve as a valuable prognostic biomarker set as well as molecular targets for therapeutic intervention of GBM.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , MicroRNAs/genética , Receptores CXCR4/genética , Animais , Sequência de Bases , Sítios de Ligação , Biomarcadores Tumorais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/mortalidade , Glioblastoma/patologia , Camundongos , MicroRNAs/química , Prognóstico , Interferência de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Clin Cancer Res ; 20(7): 1803-13, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24523440

RESUMO

PURPOSE: To determine the prognostic significance of miR-663 in glioblastoma, its effect in tumor progression, and the underlying mechanism. EXPERIMENTAL DESIGN: Specimens from 256 cases of patients with glioma, including 239 patients with follow-up information, were used to analyze the association between miR-663 and patients' prognosis by Kaplan-Meier and multivariate Cox regression analyses. The effects of miR-663 on glioblastoma cell proliferation and invasion were examined both in vitro and in vivo. Bioinformatics prediction and signal network analysis were applied to identify the putative targets of miR-663, which were further verified by luciferase reporter assay, rescue experiments as well as the immunohistochemistry (IHC) and Western blotting examination of downstream effectors. Quantitative reverse transcriptase PCR (qRT-PCR) and IHC were applied to investigate the clinical association between miR-663 and its target in human glioblastoma specimens. RESULTS: miR-663 was inversely correlated with glioma grades but positively correlated with patients' survival. Furthermore, two distinct subgroups of patients with glioblastoma with different prognoses were identified on the basis of miR-663 expression in our specimens and that from The Cancer Genome Atlas (TCGA) database. Overexpression of miR-663 significantly suppressed the proliferation and invasion of glioblastoma cells in vitro and in vivo. Mechanistically, we discovered PIK3CD as a direct target of miR-663 and found that phosphorylated AKT and three key downstream effectors of PIK3CD, i.e., CCND1, MMP2, and MMP7, were downregulated by miR-663 overexpression. Moreover, PIK3CD was inversely correlated with miR-663 in glioblastoma specimens and predicted poor prognosis of patients with glioblastoma. CONCLUSION: miR-663 is a novel prognostic biomarker and a potential therapeutic candidate for glioblastoma.


Assuntos
Neoplasias Encefálicas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Glioblastoma/genética , MicroRNAs/genética , Adulto , Idoso , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Zhejiang Univ Sci B ; 12(10): 812-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21960344

RESUMO

OCT4, a member of the POU family of gene products, is an octamer motif-binding transcription factor. As it is known to play a crucial role in cancer processes including proliferation, invasion, and chemoradioresistance, it is important to identify the direct targets of OCT4 in living cancer cells. Here, chromatin immunoprecipitation-sequencing (ChIP-seq) was used to identify OCT4 binding sites in glioblastoma cancer cells. The results showed that 5438 OCT4 binding sites were localized in the glioblastoma cancer genome and that these sites contained a consensus sequence TTTkswTw (k=T or G, s=C or G, w=A or T), which occurred 3931 times in 2312 OCT4 binding regions. Furthermore, binding motifs of some other transcription factors were identified in OCT4 binding regions. Our results provide a valuable dataset for understanding gene regulation mechanisms underlying the function of OCT4 in glioblastoma cancer.


Assuntos
Neoplasias Encefálicas/etiologia , Genoma Humano , Glioblastoma/etiologia , Fator 3 de Transcrição de Octâmero/fisiologia , Especificidade de Anticorpos , Sítios de Ligação , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Glioblastoma/genética , Humanos , Fatores de Transcrição/metabolismo
19.
Int Immunopharmacol ; 10(12): 1602-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20933627

RESUMO

Endothelial progenitor cells (EPCs) are involved in tumor neovascularization with undefined mechanisms. In this study, we explored the role of formylpeptide receptor, a G protein-coupled receptor, expressed by human malignant glioma cells in neovascularization of malignant glioma. EPCs were isolated from human umbilical cord blood and their migratory capability and tubulogenesis induced by the supernatant of U87 glioblastoma (GBM) cell line were examined. We also assessed the recruitment and incorporation of EPCs into orthotopic intracranial tumors formed by implanted U87 GBM cells. The supernatant of control U87 cells induced high levels of migration and tubule-formation in vitro by EPCs. In contrast, the chemotactic and tubule-stimulating activities on EPCs in the supernatant of U87 cells with FPR knocking down by small interference (si) RNA were significantly attenuated. In addition, the number of EPCs recruited and incorporated into intracranial glioma xenografts was significantly higher in tumors formed by control U87 cells than tumors formed by U87 cells containing FPR-siRNA. Our results suggest that expression of functional FPR in glioma cells plays an important role in regulating vasculogenesis by EPCs, which constitute a novel target for anti-angiogenic therapy in gliomas.


Assuntos
Endotélio Vascular/patologia , Glioma/irrigação sanguínea , Neovascularização Patológica , Receptores de Formil Peptídeo/biossíntese , Células-Tronco/patologia , Animais , Comunicação Celular , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular , Quimiotaxia , Meios de Cultivo Condicionados , Feminino , Glioma/metabolismo , Glioma/patologia , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores de Formil Peptídeo/genética
20.
Asian J Androl ; 11(4): 484-91, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19448646

RESUMO

Asthenozoospermia (AS) is a common cause of human male infertility. In one study, more than 80% of the samples from infertile men had reduced sperm motility. Seminal plasma is a mixture of secretions from the testis, epididymis and several male accessory glands, including the prostate, seminal vesicles and Cowper's gland. Studies have shown that seminal plasma contains proteins that are important for sperm motility. To further explore the pathophysiological character of AS, we separated the seminal plasma proteins from AS patients and healthy donors using sodium dodecyl sulfate polyacrylamide gel electrophoresis and in-gel digestion, and then subjected the proteins to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. A total of 741 proteins were identified in the seminal plasma, with a false discovery rate of 3.3%. Using spectral counting, we found that 45 proteins were threefold upregulated and 56 proteins were threefold downregulated in the AS group when compared with the control. Most of these proteins originated from the epididymis and prostate. This study identified a rich source of biomarker candidates for male infertility and indicates that functional abnormalities of the epididymis and prostate can contribute to AS. We identified DJ-1-a protein that has been shown elsewhere to be involved in the control of oxidative stress (OS)-as a downregulated protein in AS seminal plasma. The levels of DJ-1 in AS seminal plasma were about half of those in the control samples. In addition, the levels of reactive oxygen species were 3.3-fold higher in the AS samples than in the controls. Taken together, these data suggest that downregulation of DJ-1 is involved in OS in semen, and therefore affects the quality of the semen.


Assuntos
Astenozoospermia/metabolismo , Estresse Oxidativo , Proteínas/metabolismo , Proteômica , Sêmen/metabolismo , Western Blotting , Cromatografia Líquida , Humanos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas em Tandem
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