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1.
Acta Pharmacol Sin ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907048

RESUMO

Adjuvants for vaccines with characteristics of improving adaptive immunity particularly via leverage of antigen presenting cells (APCs) are currently lacking. In a previous work we obtained a new soluble 300 kDa homogeneous ß-glucan named GFPBW1 from the fruit bodies of Granola frondosa. GFPBW1 could activate macrophages by targeting dendritic cell associated C-type lectin 1 (Dectin-1)/Syk/NF-κB signaling to achieve antitumour effects. In this study the adjuvant effects of GFPBW1 were explored with OVA-antigen and B16-OVA tumor model. We showed that GFPBW1 (5, 50, 500 µg/mL) dose-dependently promoted activation and maturation of APCs in vitro by increasing CD80, CD86 and MHC II expression. We immunized female mice with OVA in combination with GFPBW1 (50 or 300 µg) twice with an interval of two weeks. GFPBW1 markedly and dose-dependently increased OVA-specific antibody titers of different subtypes including IgG1, IgG2a, IgG2b and IgG3, suggesting that it could serve as an adjuvant for both Th1 and Th2 type immune responses. Furthermore, GFPBW1 in combination with aluminum significantly increased the titers of OVA-specific IgG2a and IgG2b, but not those of IgG1, suggesting that GFPBW1 could be used as a co-adjuvant of aluminum to compensate for Th1 deficiency. For mice immunized with OVA plus GFPBW1, no obvious pathological injury was observed in either major organs or injection sites, and no abnormalities were noted for any of the hematological parameters. When GFPBW1 served as an adjuvant in the B16-OVA cancer vaccine models, it could accomplish entire tumor suppression with preventive vaccines, and enhance antitumour efficacy with therapeutic vaccines. Differentially expressed genes were found to be enriched in antigen processing process, specifically increased tumor infiltration of DCs, B1 cells and plasma cells in the OVA plus GFPBW1 group, in accordance with its activation and maturation function of APCs. Collectively, this study systematically describes the properties of GFPBW1 as a novel potent and safe adjuvant and highlights its great potential in vaccine development.

2.
Heliyon ; 9(12): e22768, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076064

RESUMO

Background: Fatty acid metabolism (FAM) is closely connected with tumorigenesis as well as disease progression and affects the efficacy of platinum-based drugs. Exploring biomarkers related to FAM in bladder cancer (BLCA) is essential to improve cancer prognosis. Methods: High-throughput sequencing data from The Cancer Genome Atlas (TCGA) were bioinformatically resolved to identify molecular subtypes of fatty acid metabolic profiles in BLCA using coherent clustering analysis. Based on fatty acid metabolic profile, a prognostic model was created using COX and LASSO COX models. CIBERSORT, Estimation of STromal and Immune cells in MAlignant Tumours using Expression (ESTIMATE), MCP-Count, and single sample gene set enrichment analysis (ssGSEA) were used to assess the differences in tumor microenvironment (TME) among different molecular subtypes, prognostic groups. Kaplan-Meier (K-M) survival curve was plotted to assess patients' prognosis. Receiver operating characteristic curve (ROC) and the clinical prognostic value of prognostic models was evaluated by the Nomogram. Results: Three molecular subtypes (FAMC1, FAMC2, FAMC3) of fatty acid metabolic patterns were determined. FAMC1 showed significant prognostic advantage with immunoreactivity. Five key prognostic FAMGs were identified and RiskScore was developed. We found that patients with low RiskScore showed significantly better immune microenvironment status, survival and response to immunotherapy. Similarly, both Nomogram and RiskScore demonstrated excellent prognostic value. Conclusions: In conclusion, our study showed that the RiskScore was closely related to the clinical traits of BLCA patients. The RiskScore may provide essential clinical guidance for predicting prognosis and treatment response in bladder cancer.

3.
Glycobiology ; 33(10): 766-783, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37658770

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant cancer with limited treatment options. Mannose, a common monosaccharide taken up by cells through the same transporters as glucose, has been shown to induce growth retardation and enhance cell death in response to chemotherapy in several cancers, including PDAC. However, the molecular targets and mechanisms underlying mannose's action against PDAC are not well understood. In this study, we used an integrative approach of network pharmacology, bioinformatics analysis, and experimental verification to investigate the pharmacological targets and mechanisms of mannose against PDAC. Our results showed that the protein Src is a key target of mannose in PDAC. Additionally, computational analysis revealed that mannose is a highly soluble compound that meets Lipinski's rule of five and that the expression of its target molecules is correlated with survival rates and prognosis in PDAC patients. Finally, we validated our findings through in vitro and in vivo experiments. In conclusion, our study provides evidence that mannose plays a critical role in inhibiting PDAC growth by targeting Src, suggesting that it may be a promising therapeutic candidate for PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Manose , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Neoplasias Pancreáticas
4.
Int J Biol Macromol ; 245: 125540, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355063

RESUMO

Gardenia jasminoides (GJ) is a classic edible medicine in China of which the fruit has been proved to alleviate liver damage. We hypothesized whether polysaccharide in the fruit could have comparable bioactivity. To address this, a novel polysaccharide GJE0.2-2, is purified from the fruit of Gardenia jasminoides. Indeed, GJE0.2-2 may attenuate CCl4-induced liver fibrosis in mice and impede the expression of critical fibrogenesis associated molecules such as α-SMA, FN1, and Collagen I induced by TGF-ß in human hepatic stellate LX-2 cells. Mechanism studies suggest that this bioactivity may be implicated in TLR4/NF-κB signaling pathway via directly binding to TLR4. The structure characterization shows that the backbone of this polysaccharide is mainly composed of galacturonic acid with minor rhamnose, branched with galactose and arabinose, galacturonic acid, and esterified hexenuronic acid (HexpA). These findings provide evidence for a novel pectin-linked polysaccharide-based new drug candidate development for liver fibrosis therapy.

5.
Fitoterapia ; 169: 105552, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37257698

RESUMO

The accumulation of amyloid ß (Aß) containing senile plaques is one of the key histopathological hallmarks of Alzheimer's disease (AD). Increasing evidences demonstrated the important role of autophagy in Aß clearance. Recent studies implied that extracts from Semiaquilegia adoxoides (DC.) Makino could ameliorate the memory of D-galactose induced aging mice. However, the bioactive substance and underlying mechanism remains unknown. Thus, the present study sought to explore the effects of a novel homogenous peptidoglycan on Aß42 secretion and the underlying mechanism. Briefly, we extracted a novel peptidoglycan named SA02C using hot water extraction and alcohol precipitation with the Mw of 13.72 kDa. SA02C contains 73.33% carbohydrate and 27.83% protein. The structure characterization revealed that its glycan part might mainly composed of galacturonic acid with minor rhamnose in backbone, and branched with glucose, galactose, arabinose, xylose and galacturonic acid. The protein or peptide moiety in SA02C was bonded to the polysaccharide via threonine. Bioactivities test showed that SA02C could reduce Aß42 production in a dose dependent manner with no obvious cytotoxicity. Mechanism study demonstrated that SA02C could modulate APP processing by upregulating the expression of ADAM10, sAPPα and downregulating BACE1, sAPPß. Furthermore, SA02C also could stimulate autophagy by promoting the expression of the markers of autophagy such as LC3B and ATG5, resulting in the promotion of Aß42 phagocytosis.


Assuntos
Doença de Alzheimer , Semiaquilegia , Camundongos , Animais , Peptídeos beta-Amiloides , Secretases da Proteína Precursora do Amiloide , Peptidoglicano , Ácido Aspártico Endopeptidases/metabolismo , Estrutura Molecular , Doença de Alzheimer/tratamento farmacológico , Autofagia , Polissacarídeos
6.
Chin Med J (Engl) ; 136(10): 1207-1215, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37010251

RESUMO

BACKGROUND: LY01005 (Goserelin acetate sustained-release microsphere injection) is a modified gonadotropin-releasing hormone (GnRH) agonist injected monthly. This phase III trial study aimed to evaluated the efficacy and safety of LY01005 in Chinese patients with prostate cancer. METHODS: We conducted a randomized controlled, open-label, non-inferiority trial across 49 sites in China. This study included 290 patients with prostate cancer who received either LY01005 or goserelin implants every 28 days for three injections. The primary efficacy endpoints were the percentage of patients with testosterone suppression ≤50 ng/dL at day 29 and the cumulative probability of testosterone ≤50 ng/dL from day 29 to 85. Non-inferiority was prespecified at a margin of -10%. Secondary endpoints included significant castration (≤20 ng/dL), testosterone surge within 72 h following repeated dosing, and changes in luteinizing hormone, follicle-stimulating hormone, and prostate specific antigen levels. RESULTS: On day 29, in the LY01005 and goserelin implant groups, testosterone concentrations fell below medical-castration levels in 99.3% (142/143) and 100% (140/140) of patients, respectively, with a difference of -0.7% (95% confidence interval [CI], -3.9% to 2.0%) between the two groups. The cumulative probabilities of maintaining castration from days 29 to 85 were 99.3% and 97.8%, respectively, with a between-group difference of 1.5% (95% CI, -1.3% to 4.4%). Both results met the criterion for non-inferiority. Secondary endpoints were similar between groups. Both treatments were well-tolerated. LY01005 was associated with fewer injection-site reactions than the goserelin implant (0% vs . 1.4% [2/145]). CONCLUSION: LY01005 is as effective as goserelin implants in reducing testosterone to castration levels, with a similar safety profile. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04563936.


Assuntos
Gosserrelina , Neoplasias da Próstata , Humanos , Masculino , Antineoplásicos Hormonais/uso terapêutico , População do Leste Asiático , Hormônio Liberador de Gonadotropina/agonistas , Gosserrelina/uso terapêutico , Antígeno Prostático Específico , Neoplasias da Próstata/tratamento farmacológico , Testosterona
7.
Glycoconj J ; 39(6): 725-735, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36306024

RESUMO

A homogeneous polysaccharide named as LJW2F2 was extracted and purified from the flowers of Lonicera japonica Thunb. Structural characteristic indicated that LJW2F2 was a homogalacturonan composed of α-1,4-D-galacturonic acid with a molecular weight of 7.2 kDa. Previous investigation suggested that homogalacturonan might impede angiogenesis, however the mechanism is still vague. Here we reported that LJW2F2 significantly disrupted capillary-like tube formation of human microvascular endothelia cells (HMEC-1) on matrigel as well as the cells migration. Mechanism study revealed that LJW2F2 might inactivate phosphorylation of epidermal growth factor receptor (EGFR), subsequently suppress Raf, mitogen-activated protein kinase (MEK) and extracellular-related kinase (ERK) phosphorylation. Moreover, LJW2F2 markedly decreased the expression of Notch1 and Delta-like ligand 4 (Dll4). Therefore, our results suggested that LJW2F2 might be a potential angiogenesis inhibitor via disturbing multiple signaling pathways.


Assuntos
Lonicera , Humanos , Lonicera/química , Transdução de Sinais , Receptores ErbB/análise , Flores/química , Polissacarídeos/química
8.
J Agric Food Chem ; 70(32): 9908-9918, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35924862

RESUMO

The fruit of Fructus Mori is food and medicine, which has been demonstrated to have a significant neuroprotective effect. However, the effective constituent remains unknown. We speculate that the glycopeptide in the extract of the fruit has similar activity. To address this hypothesis, we isolated a novel pectin-like glycopeptide (FMP-6-S4) with a molecular weight of 11.23 kDa from the fruit. It contains about 20% of peptide comprising 17 amino acids and 80% glycan consisting of L-rhamnose (L-Rha), D-galactose (D-Gal), D-galacturonic acid (D-GalA), L-arabinose (L-Ara) and d-glucose (D-Glc) in molar ratios of 7.25:4.62:77.66:5.62:4.85. The backbone of the glycan part consisted of 1,4-linked α-D-GalpA and 1, 2-linked α-L-Rhap, while the branches were composed of hexenuronic acid (HexA) substituted at the C-3 position of partial galacturonic acid, and traces of galactose, glucose, and arabinose were substituted at the C-4 position of rhamnose. The in vitro experiments revealed that FMP-6-S4 might inhibit Aß42 (ß-amyloid peptides 42) aggregation and decrease Aß42 production by modulating APP (amyloid precursor protein) processing.


Assuntos
Frutas , Pectinas , Arabinose/química , Frutas/química , Galactose/química , Glicopeptídeos , Pectinas/química , Polissacarídeos/química , Ramnose
10.
Chin J Nat Med ; 18(5): 345-355, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32451092

RESUMO

Cordycepin (3'-deoxyadenosine) from Cordyceps militaris has been reported to have anti-tumor effects. However, the molecular target and mechanism underlying cordycepin impeding pancreatic cancer cell growth in vitro and in vivo remain vague. In this study, we reported functional target molecule of cordycepin which inhibited pancreatic cancer cells growth in vitro and in vivo. Cordycepin was confirmed to induce apoptosis by activating caspase-3, caspase-9 and cytochrome c. Further studies suggested that MAPK pathway was blocked by cordycepin via inhibiting the expression of Ras and the phosphorylation of Erk. Moreover, cordycepin caused S-phase arrest and DNA damage associated with activating Chk2 (checkpoint kinase 2) pathway and downregulating cyclin A2 and CDK2 phosphorylation. Very interestingly, we showed that cordycepin could bind to FGFR2 (KD = 7.77 × 10-9) very potently to inhibit pancreatic cancer cells growth by blocking Ras/ErK pathway. These results suggest that cordycepin could potentially be a leading compound which targeted FGFR2 to inhibit pancreatic cells growth by inducing cell apoptosis and causing cell cycle arrest via blocking FGFR/Ras/ERK signaling for anti-pancreatic cancer new drug development.


Assuntos
Cordyceps/química , Desoxiadenosinas/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/fisiopatologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética
11.
Carbohydr Polym ; 204: 111-123, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30366522

RESUMO

Pancreatic ductal adenocarcinoma is a highly malignant gastrointestinal tumor. Molecular targeting therapy for pancreatic cancer is still limited. High expressed Galectin-3 in pancreatic cancer is positively correlated with disease progression, indicating that Galectin-3 can be employed as a predictor of poor prognosis. From safflower, we isolated and purified a homogeneous polysaccharide, HH1-1, which could bind to and inhibit Galectin-3. HH1-1 could block the interaction between Galectin-3 and EGFR. Following HH1-1 treatment, the binding ability between EGFR and Galectin-3 was reduced by 245.28 folds. HH1-1 could suppress pancreatic cancer cell proliferation, arrest the cell cycle in S phase, induce cell apoptosis, inhibit angiogenesis and impede tumor cell migration and invasion. Moreover, HH1-1 affected the Galectin-3/EGFR/AKT/FOXO3 signaling pathway and possessed anti-pancreatic cancer activity in vitro and in vivo, especially in patient-derived xenografts. Further study suggested that HH1-1 had almost no toxicity both in vitro and in vivo. This adds new evidence to suggest that HH1-1 could be a promising therapeutic agent and support the pursuit of the Galectin-3 as a target in pancreatic cancer treatment.


Assuntos
Antineoplásicos/uso terapêutico , Galactanos/uso terapêutico , Galectina 3/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Sanguíneas , Carthamus tinctorius/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Proteína Forkhead Box O3/metabolismo , Galactanos/farmacologia , Galectina 3/metabolismo , Galectinas , Humanos , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos
12.
Carbohydr Polym ; 201: 65-74, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30241864

RESUMO

Here, a pectin LBP1C-2 with the molecular weight of 99.8 kDa was purified from fruits of Lycium barbarum L. Its structure was elucidated as a backbone of alternate 1, 2-linked α-Rhap and 1, 4-linked α-GalpA, with branches of terminal (T) -, 1, 3-, 1, 6- and 1, 3, 6-linked ß-Galp, T-, 1, 5- and 1, 3, 5-linked α-Araf and T-linked ß-Rhap substituted at C-4 of 1, 2, 4-linked α-Rhap. The cell-based experiments indicated that LBP1C-2 suppressed Aß42 production in a dose-dependent manner with no cytotoxicity. Further study showed that expression of ß-site APP cleaving enzyme 1 (BACE1) was attenuated by LBP1C-2, while expression of ADAM10 was up-regulated by LBP1C-2. Moreover, LBP1C-2 promoted the expression of insulin-degradation enzyme (IDE). These results suggested that LBP1C-2 might be a leading compound for anti-Alzheimer's disease therapy by decreasing Aß42 production through mediating BACE1 and ADAM10 as well as IDE expression.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Frutas/química , Lycium/química , Pectinas , Pectinas/química , Pectinas/isolamento & purificação
13.
Carbohydr Polym ; 195: 643-651, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29805023

RESUMO

The ß amyloid (Aß) induced neurodegeneration is believed to be one of pathological mechanisms of Alzheimer's disease (AD). The inhibition of Aß production or aggregation is one of the promising therapeutic strategies for anti-AD drug discovery. Here, a homogeneous neutral polysaccharide designated LBP1A1-1 with an average molecular weight of 45.0 kDa was purified from fruits of Lycium barbarum L. Its structure was characterized to possess a backbone of 1, 3-linked ß-Galp, 1, 6-linked ß-Galp, 1, 4-linked α-Glcp with branches substituted at C-3 position of 1, 6-linked ß-Galp or C-6 position of 1, 3-linked ß-Galp. The branches contained terminal (T)-linked ß-Galp, T-linked α-Araf, T-linked ß-Araf, 1, 5-linked α-Araf and T-linked ß-Rhap. The in vitro experiments revealed that LBP1A1-1 could inhibit Aß42 production and impede Aß42 aggregation in a dose-dependent-manner without cytotoxicity. These results suggested that LBP1A1-1 might have the multiple potential for the treatment of AD.

14.
Eur J Med Chem ; 146: 613-620, 2018 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-29407985

RESUMO

Ganglioside GM3 is implicated in a variety of physiological and pathological processes. Due to GM3 exposes on the outer surface of cell membranes, it is strongly associated with cell adhesion, motility and differentiation. Neurite outgrowth is a key process in the development of functional neuronal circuits and regeneration of the nervous system after injury. In the present study, we used enzymatic hydrolysis and chemical synthesis to obtain novel galactose containing GM3 analogues. By enzymatic hydrolysis to prepare GM3 building block, we can avoid multiple chemical procedures. Next, we employed the PC12 cells as a model to evaluate the effects of GM3 analogues on neurite outgrowth with or without NGF induction. The biological tests showed that GM3 analogues could induce neurite outgrowth, which provides the valuable sights for potential nervous system treatment after injury.


Assuntos
Gangliosídeo G(M3)/farmacologia , Neurônios/efeitos dos fármacos , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Gangliosídeo G(M3)/síntese química , Gangliosídeo G(M3)/química , Hidrólise , Estrutura Molecular , Neurônios/metabolismo , Neurônios/patologia , Células PC12 , Ratos , Relação Estrutura-Atividade
15.
Cancer Lett ; 382(1): 44-52, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27569654

RESUMO

Fucoidan may inhibit angiogenesis. However, its functional target molecule and the underlying mechanism are still vague. In the present study, we showed that sulfated fucoidan FP08S2 from Sargassum fusiforme inhibited tube formation as well as migration and invasion of human microvascular endothelial cells (HMEC-1). In addition, FP08S2 was confirmed to disrupt VEGF-induced angiogenesis both in vitro and in vivo. Further study indicated that FP08S2 could bind to both VEGF and VEGFR2 to interfere with VEGF-VEGFR2 interaction. Moreover, VEGFR2/Erk/VEGF signaling pathway was blocked by FP08S2 in HMEC-1 cells. Importantly, FP08S2 impeded the growth and microvessel formation of A549 cancer cell xenograft in nude mice. These results suggested that FP08S2 presented remarkable anti-angiogenic activity via blocking VEGF signaling and could be a potential novel leading compound to inhibit lung cancer cell growth.


Assuntos
Inibidores da Angiogênese/farmacologia , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neovascularização Patológica , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Células A549 , Animais , Movimento Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Relação Dose-Resposta a Droga , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Neovascularização Fisiológica/efeitos dos fármacos , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Oncotarget ; 7(18): 26388-99, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27049919

RESUMO

Malignant gliomas are the most common form of intrinsic primary brain tumors worldwide. Alterations in microRNAs play a role in highly invasive malignant glioma, but detail mechanism still unknown. In this study, the role and mechanism of microRNA-149 (miR-149) in glioma are investigated. We show that miR-149 is expressed at substantially higher levels in glioma than in normal tissues. Stable overexpression of miR-149 augments potent prosurvival activity, as evidenced by promotion of cell viability, inhibition of apoptosis, and induced xenografted tumor growth in vivo. We further show that Caspase-2 is identified as a functional target of miR-149 and expression of caspase-2 is inversely associated with miR-149 in vitro. In addition, miR-149 promotes tumor survival in the U87-MG and A172 cell lines and it targets caspase-2 via inactivation of the p53 and p21 pathways. There results support a special role for miR-149 by targeting Caspase-2 to impact on p53 signaling pathway. We speculate that miR-149 has distinct biological functions in p53 wild type cells and p53 mutation cells, and the mechanisms involved remain to be explored in future. Our study suggests that targeting miR-149 may be a novel therapy strategy for treating p53 wild type glioma tumors in humans.


Assuntos
Neoplasias Encefálicas/patologia , Caspase 2/metabolismo , Cisteína Endopeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Glioma/patologia , MicroRNAs/metabolismo , Adulto , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Caspase 2/genética , Cisteína Endopeptidases/genética , Progressão da Doença , Feminino , Glioma/genética , Glioma/metabolismo , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade
17.
Carbohydr Polym ; 136: 899-907, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26572427

RESUMO

A fucoidan FP08S2 was isolated from the boiling-water extract of Sargassum fusiforme, purified by CaCl2 precipitation and chromatography on DEAE-cellulose and Sephacryl S-300. FP08S2 contained fucose, xylose, galactose, mannose, glucuronic acid, and 20.8% sulfate. The sulfate groups were attached to diverse positions of fucose, xylose, mannose, and galactose residues. The backbone of FP08S2 consisted of alternate 1,2-linked α-D-Manp and 1,4-linked ß-D-GlcpA. Sugar composition analysis and ESI-MS revealed that the oligosaccharides from branches contained fucose, xylose, galactose, glucuronic acid and sulfate. FP08S2 could significantly inhibit tube formation and migration of human microvascular endothelial cells (HMEC-1) dose-dependently. These results suggested that the fucoidan FP08S2 from brown seaweeds S. fusiforme could be a potent anti-angiogenic agent.


Assuntos
Inibidores da Angiogênese/química , Polissacarídeos/química , Inibidores da Angiogênese/farmacologia , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Humanos , Monossacarídeos/análise , Polissacarídeos/farmacologia , Sargassum/química , Cicatrização/efeitos dos fármacos
18.
Int J Biol Macromol ; 69: 252-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24877643

RESUMO

An alginate fraction, 04S2P, was isolated from the brown seaweed Sargassum fusiforme and was structurally characterized by the ratio (M/G) of ß-d-mannuronic acid residues (M) to α-l-guluronic acid residues (G) via (1)H and (13)C NMR spectroscopy. When compared to commercial alginate (Alg) and alginates from other brown algae, 04S2P has a higher M/G ratio of 9.0:1.0 as determined by a modified high-performance liquid chromatography method after pre-column derivatization with PMP. Furthermore, the sulfated polysaccharides 04S2P-S and Alg-S were prepared by the chlorosulfonic acid-pyridine method. Both C-2 and/or C-3 of M and G residues of 04S2P-S were substituted by sulfate groups, with C-3 of M residues preferentially substituted. Their effects on tube formation of HMEC-1 cells were examined, and the results indicated that the sulfated Alg, Alg-S, exhibited a strong anti-angiogenic effect on HMEC-1 cells. The anti-tumor activity of native and sulfated alginates was tested on five different tumor cell lines. Alg-S demonstrated significant anti-tumor effects on the Bel7402, SMMC7721, and HT-29 cell lines, whereas 04S2P-S showed a distinct anti-tumor effect only on the Bel7402 cell line.


Assuntos
Alginatos/química , Alginatos/farmacologia , Sargassum/química , Sulfatos/química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Humanos , Relação Estrutura-Atividade
19.
Carbohydr Res ; 393: 43-50, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24887706

RESUMO

COB1B1S2 was isolated from an alkaline extract of Cassia obtusifolia seeds, and purified by anion-exchange and gel permeation chromatography. It contains arabinose, xylose, and glucuronic acid, in the molar ratio of 5:81:14, with an apparent molecular weight estimated to be 70.4 kDa. Elucidated by using chemical and spectroscopic methods, COB1B1S2 was shown to have a backbone consisting of 1,4-linked ß-D-Xylp, with one single-unit terminal α-D-GlcpA or α-L-Araf substituted at O-2 for nearly every five 1,4-linked Xylp. COB1B1S2 is structurally different from typical glucuronoxylans by its absence of methylation at O-4 of GlcA. The native COB1B1S2 showed no significant inhibition on the tube formation of human microvascular endothelial cells (HMEC) and on the growth of liver and colon cancer cells. On the contrary, COB1B1S2-Sul, prepared as the sulfated derivative of COB1B1S2, exhibited a significant inhibition on tube formation of HMEC in a dose-dependent manner, and on the growth of Bel7402 liver cancer cells. These results indicated that the introduction of sulfate groups significantly enhanced the biological activity of glucuronoxylan.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cassia/química , Células Endoteliais/efeitos dos fármacos , Sementes/química , Sulfatos/química , Xilanos/química , Xilanos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Células CACO-2 , Configuração de Carboidratos , Sequência de Carboidratos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Dados de Sequência Molecular , Relação Estrutura-Atividade , Sulfatos/isolamento & purificação , Sulfatos/farmacologia , Xilanos/isolamento & purificação
20.
Carbohydr Polym ; 110: 142-7, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-24906740

RESUMO

Inhibition of Aß aggregation and attenuation of its cytotoxicity are considered to valuable therapeutics for Alzheimer's disease (AD). Here, a glucan named as LJW0F2 was purified from flowers of Lonicera japonica Thunb. Using monosaccharides composition analysis, methylation analysis, IR and NMR spectroscopy, this polysaccharide was elucidated to be an α-D-(1→4)-glucan with an α-(1→4) linked branch attached to the C-6 position. Its inhibitory effect on Aß42 aggregation was measured by fluorescence spectroscopic analysis with thioflavine T (ThT) and atomic force microscopy (AFM). We showed that polysaccharide LJW0F2 could inhibit Aß42 aggregation in a dose-dependent-manner. Besides, LJW0F2 could attenuate the cytotoxicity induced by Aß42 aggregation in SH-SY5Y neuroblastoma cells. To the best of our knowledge, this was the first report that the exogenous plant-derived polysaccharide might block Aß42 aggregation directly and reduce its toxicity in SH-SY5Y cells.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Medicamentos de Ervas Chinesas/isolamento & purificação , Flores , Glucanos/isolamento & purificação , Lonicera , Fragmentos de Peptídeos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Medicamentos de Ervas Chinesas/farmacologia , Glucanos/farmacologia , Humanos
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