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1.
BMC Ophthalmol ; 23(1): 173, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095450

RESUMO

AIM: To evaluate association between pretreatment serum metrics and best corrected visual acuity ( BCVA) of patients with macular edema secondary to retinal vein occlusion and its subtypes after intravitreal ranibizumab or conbercept implant. METHODS: This prospective research included 201 patients(201 eyes) who were diagnosed with macular edema secondary to retinal vein occlusion at Heibei Eye Hospital between January 2020 and January 2021, who all received intravitreal anti- vascular endothelial growth factor treatment. Serum metrics were measured before the first treatment, and correlations between BCVA and each of four parameters- platelets, neutrophil- to- lymphocyte ratio(NLR), platelet- to- lymphocyte ratio(PLR) and monocyte- to- lymphocyte ratio(MLR)- were analyzed to identify predictors of effective intravitreal injection treatment outcomes. RESULTS: The mean platelets was significantly different in the effective and ineffective group for RVO-ME (273.02 ± 41.49 × 109/L,214.54 ± 44.08 × 109/L P < 0.01),BRVO-ME (269.43 ± 49.52 × 109/L,214.72 ± 40.42 × 109/L P < 0.01), and CRVO-ME (262.32 ± 32.41 × 109/L,209.27 ± 42 0.91 × 109/L P < 0.01). The cutoff value of the platelets was 266.500, the area under the curve was 0.857,and the sensitivity and specificity were 59.8% and 93.6%, respectively. The mean PLR was significantly different in the effective and ineffective group for RVO-ME (154.66 ± 49.60, 122.77± 44.63 P < 0.01),BRVO-ME (152.24 ± 54.99, 124.72 ± 41.46 P = 0.003), and CRVO-ME (152.06±44.23, 118.67 ± 41.80 P = 0.001). The cutoff value of the platelets was 126.734, the area under the curve was 0.699, and the sensitivity and specificity were 70.7% and 63.3%, respectively. There were no statistical differencies between the effective and ineffective group(RVO- ME and its subtypes) in NLR and MLR. CONCLUSION: Higher pretreatment platelets and PLR were associated with BCVA in patients with RVO- ME and its subtypes who were treated with anti- VEGF drugs. The platelets and PLR may be used as predictive and prognostic tools for effective intravitreal injection treatment outcomes.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Humanos , Oclusão da Veia Retiniana/tratamento farmacológico , Edema Macular/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular , Dexametasona , Glucocorticoides , Estudos Prospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Injeções Intravítreas , Inibidores da Angiogênese/uso terapêutico
2.
Mol Cell ; 41(6): 704-19, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21419345

RESUMO

Studies in yeast demonstrate that signaling kinases have a surprisingly active role in the nucleus, where they tether to chromatin and modulate gene expression programs. Despite these seminal studies, the nuclear mechanism of how signaling kinases control transcription of mammalian genes is in its infancy. Here, we provide evidence for a hitherto unknown function of protein kinase C-theta (PKC-θ), which physically associates with the regulatory regions of inducible immune response genes in human T cells. Chromatin-anchored PKC-θ forms an active nuclear complex by interacting with RNA polymerase II, the histone kinase MSK-1, and the adaptor molecule 14-3-3ζ. ChIP-on-chip reveals that PKC-θ binds to promoters and transcribed regions of genes, as well as to microRNA promoters that are crucial for cytokine regulation. Our results provide a molecular explanation for the role of PKC-θ not only in normal T cell function, but also in circumstances of its ectopic expression in cancer.


Assuntos
Cromatina/metabolismo , Regulação da Expressão Gênica , Isoenzimas/metabolismo , MicroRNAs/metabolismo , Proteína Quinase C/metabolismo , Linfócitos T/fisiologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Humanos , Interleucina-2/genética , Isoenzimas/genética , Células Jurkat , MicroRNAs/genética , Regiões Promotoras Genéticas , Proteína Quinase C/genética , Proteína Quinase C-theta , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Linfócitos T/citologia , Transcrição Gênica
3.
Diagnostics (Basel) ; 14(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39125563

RESUMO

The severity of periodontitis can be analyzed by calculating the loss of alveolar crest (ALC) level and the level of bone loss between the tooth's bone and the cemento-enamel junction (CEJ). However, dentists need to manually mark symptoms on periapical radiographs (PAs) to assess bone loss, a process that is both time-consuming and prone to errors. This study proposes the following new method that contributes to the evaluation of disease and reduces errors. Firstly, innovative periodontitis image enhancement methods are employed to improve PA image quality. Subsequently, single teeth can be accurately extracted from PA images by object detection with a maximum accuracy of 97.01%. An instance segmentation developed in this study accurately extracts regions of interest, enabling the generation of masks for tooth bone and tooth crown with accuracies of 93.48% and 96.95%. Finally, a novel detection algorithm is proposed to automatically mark the CEJ and ALC of symptomatic teeth, facilitating faster accurate assessment of bone loss severity by dentists. The PA image database used in this study, with the IRB number 02002030B0 provided by Chang Gung Medical Center, Taiwan, significantly reduces the time required for dental diagnosis and enhances healthcare quality through the techniques developed in this research.

4.
J Cell Biochem ; 114(7): 1695-703, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23386430

RESUMO

The F1F0 ATP synthase has recently become the focus of anti-cancer research. It was once thought that ATP synthases were located strictly on the inner mitochondrial membrane; however, in 1994, it was found that some ATP synthases localized to the cell surface. The cell surface ATP synthases are involved in angiogenesis, lipoprotein metabolism, innate immunity, hypertension, the regulation of food intake, and other processes. Inhibitors of this synthase have been reported to be cytotoxic and to induce intracellular acidification. However, the mechanisms by which these effects are mediated and the molecular pathways that are involved remain unclear. In this study, we aimed to determine whether the inhibition of cell proliferation and the induction of cell apoptosis that are induced by inhibitors of the cell surface ATP synthase are associated with intracellular acidification and to investigate the mechanism that underlines the effects of this inhibition, particularly in an acidic tumor environment. We demonstrated that intracellular acidification contributes to the cell proliferation inhibition that is mediated by cell surface ATP synthase inhibitors, but not to the induction of apoptosis. Intracellular acidification is only one of the mechanisms of ecto-ATP synthase-targeted antitumor drugs. We propose that intracellular acidification in combination with the inhibition of cell surface ATP generation induce cell apoptosis after cell surface ATP synthase blocked by its inhibitors. A better understanding of the mechanisms activated by ecto-ATP synthase-targeted cancer therapies may facilitate the development of potent anti-tumor therapies, which target this enzyme and do not exhibit clinical limitations.


Assuntos
Adenosina Trifosfatases/metabolismo , Acidose/enzimologia , Acidose/metabolismo , Animais , Apoptose/fisiologia , Western Blotting , Células CHO , Linhagem Celular , Proliferação de Células , Cricetinae , Cricetulus , Imunofluorescência , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal , Células PC12 , Ratos
5.
BMC Cancer ; 13: 359, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23885995

RESUMO

BACKGROUND: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a multifunctional Ig-like cell adhesion molecule that has a wide range of biological functions. According to previous reports, serum CEACAM1 is dysregulated in different malignant tumours and associated with tumour progression. However, the serum CEACAM1 expression in non-small-cell lung carcinomas (NSCLC) is unclear. The different expression ratio of CEACAM1-S and CEACAM1-L isoform has seldom been investigated in NSCLC. This research is intended to study the serum CEACAM1 and the ratio of CEACAM1-S/L isoforms in NSCLC. METHODS: The expression of the serum CEACAM1 was determined by enzyme-linked immunosorbent assay. The protein expression and the location of CEACAM1 in tumours were observed by immunohistochemical staining. The CEACAM1 mRNA levels in tumour and normal adjacent tissues were measured using quantitative real-time PCR, and the expression patterns and the rate of CEACAM1-S and CEACAM1-L were analysed by reverse transcription-PCR. RESULTS: Serum CEACAM1 levels were significantly higher in NSCLC patients compared with that from normal healthy controls (P <0.0001). 17 patients (81%) among 21 showed high expression of CEACAM1 by immunohistochemical staining. Although no significant differences were found between tumour and normal tissues on mRNA expression levels of CEACAM1 (P >0.05), the CEACAM1-S and the CEACAM1-S/L (S: L) ratios were significantly higher in tumour than normal tissues (P <0.05). CONCLUSIONS: Our data indicated that the serum levels of CEACAM1 could discriminate lung cancer patients from health donors and that CEACAM1 might be a useful marker in early diagnosis of NSCLC. Moreover, our results showed that the expression patterns of CEACAM1 isoforms could be changed during oncogenesis, even when total CEACAM1 in tumour tissues did not show significant changes. Our study suggested that the expression ratios of CEACAM1-S/CEACAM1-L might be a better diagnostic indicator in NSCLC than the quantitative changes of CEACAM1.


Assuntos
Antígenos CD/biossíntese , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Moléculas de Adesão Celular/biossíntese , Neoplasias Pulmonares/metabolismo , Adulto , Idoso , Antígenos CD/sangue , Área Sob a Curva , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Moléculas de Adesão Celular/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/sangue , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Bone Joint Res ; 11(1): 40-48, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35084211

RESUMO

AIMS: In the repair of condylar cartilage injury, synovium-derived mesenchymal stem cells (SMSCs) migrate to an injured site and differentiate into cartilage. This study aimed to confirm that histone deacetylase (HDAC) inhibitors, which alleviate arthritis, can improve chondrogenesis inhibited by IL-1ß, and to explore its mechanism. METHODS: SMSCs were isolated from synovium specimens of patients undergoing temporomandibular joint (TMJ) surgery. Chondrogenic differentiation potential of SMSCs was evaluated in vitro in the control, IL-1ß stimulation, and IL-1ß stimulation with HDAC inhibitors groups. The effect of HDAC inhibitors on the synovium and condylar cartilage in a rat TMJ arthritis model was evaluated. RESULTS: Interleukin (IL)-1ß inhibited the chondrogenic differentiation potential of SMSCs, while the HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA) and panobinostat (LBH589), attenuated inhibition of IL-1ß-induced SMSC chondrogenesis. Additionally, SAHA attenuated the destruction of condylar cartilage in rat TMJ arthritis model. IL-6 (p < 0.001) and matrix metalloproteinase 13 (MMP13) (p = 0.006) were significantly upregulated after IL-1ß stimulation, while SAHA and LBH589 attenuated IL-6 and MMP13 expression, which was upregulated by IL-1ß in vitro. Silencing of IL-6 significantly downregulated MMP13 expression and attenuated IL-1ß-induced chondrogenesis inhibition of SMSCs. CONCLUSION: HDAC inhibitors SAHA and LBH589 attenuated chondrogenesis inhibition of SMSC induced by IL-1ß in TMJ, and inhibition of IL-6/MMP13 pathway activation contributes to this biological progress. This study provides a theoretical basis for the application of HDAC inhibitors in the treatment of TMJ arthritis. Cite this article: Bone Joint Res 2022;11(1):40-48.

7.
Medicine (Baltimore) ; 98(37): e16814, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517812

RESUMO

The purpose of this study was to compare outcomes of open reduction and internal fixation (ORIF) versus closed reduction (CR) for mandibular condylar fractures.Patients included in the National Inpatient Sample (NIS) database (2005-2014) who were admitted to the hospital for unilateral mandibular condylar fracture were included in the analysis. Patient characteristics and clinical outcomes were compared between those who received ORIF and those receiving CR. Logistic regression analysis was performed to estimate odds ratios (ORs) for each aspect of the main observed events.NIS data of 12,303 patients who underwent ORIF and 4310 patients who underwent CR were analyzed. Compared to CR, ORIF had an increased risk of longer hospital stay (adjusted OR [aOR] = 1.78, 95% confidence intervals [CIs] = 1.51-2.09), higher total medical cost (aOR = 2.57, 95% CI = 2.17-3.05), and hematoma development (aOR = 10.66, 95% CI = 1.43-75.59), but had a lower risk of having wound complications (aOR = 0.86, 95% CI = 0.79-0.93).Patients with mandibular condylar fractures who receive ORIF have greater risk of having an extended hospital stay, higher total medical costs, and hematoma development but lower risk of experiencing wound complications compared to those who receive CR.


Assuntos
Fixação Interna de Fraturas , Côndilo Mandibular/lesões , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/cirurgia , Redução Aberta , Adulto , Comorbidade , Estudos Transversais , Feminino , Fixação Interna de Fraturas/economia , Custos de Cuidados de Saúde , Hematoma/epidemiologia , Hematoma/etiologia , Humanos , Pacientes Internados , Tempo de Internação/economia , Masculino , Fraturas Mandibulares/economia , Fraturas Mandibulares/epidemiologia , Redução Aberta/economia , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Resultado do Tratamento
8.
Invest Ophthalmol Vis Sci ; 53(11): 6810-7, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-22956610

RESUMO

PURPOSE: Heparanase and VEGF are related closely to angiogenesis in cancer. The purpose of our study was to evaluate the expression and correlation of heparanase and VEGF in hypoxia-induced retinal neovascularization. METHODS: C57BL/6 oxygen-induced retinopathy (OIR) mice and human retinal microvascular endothelial cells (HRECs) were treated with the hypoxia mimetic agent cobalt chloride (CoCl2), and in the presence of the heparanase inhibitor phosphomannopentaose sulfate (Muparfostat, PI-88). Heparanase activity was assayed in HRECs, and the expression of heparanase, VEGF protein and mRNA were evaluated by immunofluorescence, ELISA, Western blot, and real-time PCR while retinal flat mounts were used to evaluate the area of neovascularization of mice retina. RESULTS: HREC heparanase activity was increased by treatment with CoCl2, but was decreased by PI-88. Immunofluorescence showed that heparanase and VEGF staining was intense in hypoxia-treated HRECs and OIR mice retina, while VEGF staining was faint in the normoxia and PI-88-treated ones. Western blot and real-time PCR results indicated that the expression of heparanase and VEGF was increased under hypoxic conditions, and the increase of VEGF was inhibited by PI-88. Retinal flat mounts showed that the area of new vessels in retina of OIR mice was increased compared to the normoxic mice, and this effect was inhibited by PI-88. CONCLUSIONS: Heparanase is upregulated and associated with the VEGF expression in hypoxia-induced retinal diseases. Heparanase is involved in hypoxia-induced neovascularization through promoting VEGF expression and may be a new therapeutic target for hypoxia-induced neovascularization retinal diseases.


Assuntos
Regulação da Expressão Gênica , Glucuronidase/genética , RNA/genética , Retina/patologia , Neovascularização Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Animais Recém-Nascidos , Western Blotting , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Glucuronidase/biossíntese , Humanos , Hipóxia/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Retina/metabolismo , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/biossíntese
9.
Clin Exp Med ; 12(1): 3-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21505868

RESUMO

Ecto-ATP synthase has been considered to be an effective target for cancer recently. As inhibitors of ecto-ATP synthase were found to be cytotoxic for tumor cells, a monoclonal antibody (Mc178-Ab) against ecto-ATP synthase was generated in our previous study that exhibited both anti-angiogenic and anti-tumorigenic effects. However, the mechanism of action of Mc178-Ab and its downstream pathways for anti-tumor effects remain unclear. In this research, we intended to investigate the mechanism of the anti-tumor action of Mc178-Ab. The expressions of cell surface ATP synthase on A549 and CHO cells were confirmed by flow cytometry and confocal microscope. Proliferation and apoptosis were examined after the treatment with Mc178-Ab. In order to examine the activity of ecto-ATP synthase changed by Mc178-Ab, extracellular ATP generation and intracellular pH levels were assessed. The phosphorylation of the signaling molecules, MAPKase and Akt, was analyzed by western blot. Cell proliferation was blocked, and apoptosis was induced in A549 cells treated with Mc178-Ab, as determined by MTT assay and flow cytometry analysis of Annexin-V/PI staining separately. The intracellular pH level and extracellular ATP generation were also decreased after Mc178-Ab treatment. Finally, western blot data revealed that the phosphorylation of JNK and p38 was increased, while the phosphorylation of ERK and Akt was decreased in A549 cells treated with Mc178-Ab. Compared with A549 cells, Mc178-Ab had less effect on CHO cells. The decreased intracellular pH levels and the altered concentration of extracellular ATP may contribute to the mechanisms of the effect of Mc178-Ab on A549 and CHO cells. The results also suggested that the anti-tumor effect of Mc178-Ab was associated with MAPKase and Akt pathways.


Assuntos
Inibidores da Angiogênese/farmacologia , Anticorpos Monoclonais/metabolismo , Antineoplásicos/farmacologia , Apoptose , Sistema de Sinalização das MAP Quinases , ATPases Translocadoras de Prótons/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Anexina A5/metabolismo , Células CHO , Proliferação de Células , Cricetinae , Ativação Enzimática , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , ATPases Translocadoras de Prótons/metabolismo , Células Tumorais Cultivadas
10.
Transcription ; 3(3): 130-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22771948

RESUMO

The methylation of histones is a fundamental epigenetic process regulating gene expression programs in mammalian cells. Dysregulated patterns of histone methylation are directly implicated in malignant transformation. Here, we report the unexpected finding that the invasive extracellular matrix degrading endoglycosidase heparanase enters the nucleus of activated human T lymphocytes and regulates the transcription of a cohort of inducible immune response genes by controlling histone H3 methylation patterns. It was found that nuclear heparanase preferentially associates with euchromatin. Genome-wide ChIP-on-chip analyses showed that heparanase is recruited to both the promoter and transcribed regions of a distinct cohort of transcriptionally active genes. Knockdown and overexpression of the heparanase gene also showed that chromatin-bound heparanase is a prerequisite for the transcription of a subset of inducible immune response genes in activated T cells. Furthermore, the actions of heparanase seem to influence gene transcription by associating with the demethylase LSD1, preventing recruitment of the methylase MLL and thereby modifying histone H3 methylation patterns. These data indicate that heparanase belongs to an emerging class of proteins that play an important role in regulating transcription in addition to their well-recognized extra-nuclear functions.


Assuntos
Cromatina/metabolismo , Glucuronidase/metabolismo , Histonas/metabolismo , Linfócitos T/metabolismo , Ativação Transcricional , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Epigênese Genética , Imunofluorescência , Glucuronidase/genética , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Histonas/genética , Humanos , Metilação , Camundongos , Camundongos Endogâmicos C57BL , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
11.
Exp Biol Med (Maywood) ; 236(1): 84-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21239738

RESUMO

Oligosaccharides of hyaluronan (o-HA) can induce angiogenesis and the growth and tube formation of vascular endothelial cells (ECs) in particular. As the major o-HA receptor, CD44 has been implicated in EC function, but its role in mediating o-HA-induced EC proliferation and tube formation remains unclear. In this study, we investigated the role of CD44 in o-HA-induced proliferation and tube formation of human umbilical vein endothelial cells (HUVECs) and explored the molecular mechanisms underlying the angiogenesis process. A CD44 siRNA was delivered into HUVECs by electroporation and o-HA-induced proliferation and tube formation capacity of CD44-silenced or control HUVECs were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) and Matrigel assays. Furthermore, the changes in Src, focal adhesion kinase (FAK) and extracellular signal-regulated kinase1 and 2 (ERK1/2) phosphorylation, as well as the expression of c-jun and c-fos were examined by Western blot and realtime-polymerase chain reaction assays. Our results demonstrated that 10 µg/mL o-HA obviously induced the proliferation and tube formation in HUVECs, and stimulated the phosphorylation of Src, FAK and ERK1/2 and upregulation of c-jun and c-fos, which could be inhibited by CD44 silencing. Altogether our data suggest that CD44 functions to initiate tyrosine phosphorylation of Src, FAK and ERK1/2, and upregulates the expression of c-jun and c-fos, thus mediating o-HA-induced proliferation and tube formation in HUVECs.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endotélio Vascular/crescimento & desenvolvimento , Receptores de Hialuronatos/fisiologia , Ácido Hialurônico/farmacologia , Oligossacarídeos/fisiologia , Transdução de Sinais/fisiologia , Western Blotting , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Genes fos/efeitos dos fármacos , Genes fos/fisiologia , Genes jun/efeitos dos fármacos , Genes jun/fisiologia , Humanos , Receptores de Hialuronatos/biossíntese , Receptores de Hialuronatos/metabolismo , Oligossacarídeos/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Tirosina/metabolismo , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo , Regulação para Cima/efeitos dos fármacos
12.
Mol Cell Biol ; 29(7): 1972-86, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19158270

RESUMO

Changes in chromatin composition are often a prerequisite for gene induction. Nonallelic histone variants have recently emerged as key players in transcriptional control and chromatin modulation. While the changes in chromatin accessibility and histone posttranslational modification (PTM) distribution that accompany gene induction are well documented, the dynamics of histone variant exchange that parallel these events are still poorly defined. In this study, we have examined the changes in histone variant distribution that accompany activation of the inducible CD69 and heparanase genes in T cells. We demonstrate that the chromatin accessibility increases that accompany the induction of both of these genes are not associated with nucleosome loss but instead are paralleled by changes in histone variant distribution. Specifically, induction of these genes was paralleled by depletion of the H2A.Z histone variant and concomitant deposition of H3.3. Furthermore, H3.3 deposition was accompanied by changes in PTM patterns consistent with H3.3 enriching or depleting different PTMs upon incorporation into chromatin. Nevertheless, we present evidence that these H3.3-borne PTMs can be negated by recruited enzymatic activities. From these observations, we propose that H3.3 deposition may both facilitate chromatin accessibility increases by destabilizing nucleosomes and compete with recruited histone modifiers to alter PTM patterns upon gene induction.


Assuntos
Regulação da Expressão Gênica , Histonas/metabolismo , Linfócitos T/metabolismo , Especificidade de Anticorpos/efeitos dos fármacos , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/metabolismo , Cromatina/metabolismo , Cromatografia de Afinidade , Regulação da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Glucuronidase/metabolismo , Histonas/isolamento & purificação , Humanos , Ácidos Hidroxâmicos/farmacologia , Imunoprecipitação , Células Jurkat , Cinética , Lectinas Tipo C , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/enzimologia , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
13.
Fen Zi Xi Bao Sheng Wu Xue Bao ; 39(6): 495-501, 2006 Dec.
Artigo em Zh | MEDLINE | ID: mdl-17348201

RESUMO

To investigate the effect of hyaluronan oligosaccharides (o-HA) on endothelial cell (EC) proliferation and the possible mechanism involved. The cell proliferation was determined by cell counting and flow cytometer, and the phosphorylation of Src kinase and ERK-1/2 as well as the expression of cyclin D1 were assayed by western blot. o-HA at concentration of 10 microg/ml caused a significantly increase in both cell cycle and cell number of EC. With increasing time and amount of o-HA of exposure, there was no further increase in the growth of cells. The cell proliferation started to be significant at 12 hr and reached peak at 72 hr. At the same time,the phosphorylation of Src kinase and ERK-1/2 was enhanced after treated with l microg/ml of o-HA at 5 min and the expression of cyclin D1 was enhanced by treating PIEC cells with o-HA at 3 hr. o-HA may increase EC growth by stimulating the Src kinase and MAPK signal pathway and thus promote the proliferation of PIEC cells,in which the regulation of cyclin D1 expression may be involved.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Oligossacarídeos/farmacologia , Quinases da Família src/metabolismo , Western Blotting , Linhagem Celular , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Citometria de Fluxo , Humanos , Ácido Hialurônico/química , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Oligossacarídeos/química , Fosforilação/efeitos dos fármacos
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