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1.
Nat Prod Res ; 35(22): 4479-4485, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32233665

RESUMO

Supercritical fluid extraction was applied to obtain the lower polarity extracts from Croton crassifolius roots, and chemical investigation of which led to the isolation and identification of two new diterpenoids, named crassifolius P (1) and crassifolius Q (2). In vitro anti-proliferative activities of compounds 1 and 2 on A549, Hep-G2 and Hela tumor cell lines were evaluated. The two new compounds exhibited obvious selectivity to tumor cells with IC50 values ranging from 20.43 ± 1.18 µM to 25.72 ± 1.32 µM.


Assuntos
Cromatografia com Fluido Supercrítico , Croton , Diterpenos , Linhagem Celular Tumoral , Diterpenos/farmacologia , Estrutura Molecular , Raízes de Plantas
2.
Acta Pharmacol Sin ; 42(4): 633-640, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32737469

RESUMO

Inhibition of glycolysis process has been an attractive approach for cancer treatment due to the evidence that tumor cells are more dependent on glycolysis rather than oxidative phosphorylation pathway. Preliminary evidence shows that inhibition of phosphoglycerate kinase 1 (PGK1) kinase activity would reverse the Warburg effect and make tumor cells lose the metabolic advantage for fueling the proliferation through restoration of the pyruvate dehydrogenase (PDH) activity and subsequently promotion of pyruvic acid to enter the Krebs cycle in glioma. However, due to the lack of small molecule inhibitors of PGK1 kinase activity to treat glioma, whether PGK1 could be a therapeutic target of glioma has not been pharmacologically verified yet. In this study we developed a high-throughput screening and discovered that NG52, previously known as a yeast cell cycle-regulating kinase inhibitor, could inhibit the kinase activity of PGK1 (the IC50 = 2.5 ± 0.2 µM). We showed that NG52 dose-dependently inhibited the proliferation of glioma U87 and U251 cell lines with IC50 values of 7.8 ± 1.1 and 5.2 ± 0.2 µM, respectively, meanwhile it potently inhibited the proliferation of primary glioma cells. We further revealed that NG52 (12.5-50 µM) effectively inhibited the phosphorylation of PDHK1 at Thr338 site and the phosphorylation of PDH at Ser293 site in U87 and U251 cells, resulting in more pyruvic acid entering the Krebs cycle with increased production of ATP and ROS. Therefore, NG52 could reverse the Warburg effect by inhibiting PGK1 kinase activity, and switched cellular glucose metabolism from anaerobic mode to aerobic mode. In nude mice bearing patient-derived glioma xenograft, oral administration of NG52 (50, 100, 150 mg· kg-1·d-1, for 13 days) dose-dependently suppressed the growth of glioma xenograft. Together, our results demonstrate that targeting PGK1 kinase activity might be a potential strategy for glioma treatment.


Assuntos
Adenina/análogos & derivados , Adenina/uso terapêutico , Glioma/tratamento farmacológico , Fosfoglicerato Quinase/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Glioma/enzimologia , Humanos , Camundongos Nus , Inibidores de Proteínas Quinases/farmacologia , Efeito Warburg em Oncologia/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Orthop Surg ; 13(2): 583-591, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33314719

RESUMO

OBJECTIVE: The purpose of this paper is to investigate the effects of senescent nucleus pulposus cell (NPC)-derived exosomes (SNPC-Exo) and the roles of the P53/P21 pathway on the senescence of NPC. METHODS: The senescent phenotypes of NPC were induced by interleukin-1ß treatment. SNPC-Exo was extracted from the culture medium of senescent NPC and purified by differential centrifugation. The structure of SNPC-Exo was identified by transmission electron microscopy and western blot analysis was used to determine the exosomal marker proteins CD63 and Tsg101. Western blot analysis was performed to determine the relative expression levels of P16, P21, and P53 in NPC. Senescence-associated ß-galactosidase (SA-ß-gal) staining was used to stain the senescent NPC and a phase contrast microscope was used to observe and count the SA-ß-gal staining of NPC. The proliferation of SNPC-Exo-treated NPC was assessed using growth curve analysis and the colony formation assay. The cell cycle of SNPC-Exo-treated NPC was determined by flow cytometry. NPC were transfected with siRNA to knock down P53 and P21 expression. RESULTS: Interleukin-1ß-treated NPC had a higher percentage of SA-ß-gal positive cells (45%) than the control group (20%) and showed an increase in the relative expression of P16, P21, and P53 (P < 0.05). SNPC-Exo were positive for exosomal marker protein CD63 and Tsg 101 and negative for calnexin, and successfully internalized as previously described. SNPC-Exo-treated NPC showed an increase in the relative expression of P21 and P53 (P < 0.05). Compared with the control group, the SNPC-Exo-treated NPC showed a lower growth rate (3 times lower on the 5th day and 2 times lower on the 7th day), fewer colony-forming units (12.0%), and a higher percentage of SA-ß-gal-positive NPC (50.0%). The SNPC-Exo-treated NPC contained more G1 phase cells (68.0%) and fewer S phase (15.5%) cells than the control group (53.0% in G1 phase, 33.5% in S phase). The expression of P21 and P53 significantly decreased in SNPC-exo-treated NPC after siRNA transfection (P < 0.05), followed by a higher growth rate (2 times higher on the 5th day and 1.5 times higher on the 7th day) and lower percentage of SA-ß-gal-positive NPC (22.5%). Moreover, the inhibition of the P53/P21 pathway promoted the SNPC-Exo-treated NPC to enter the S phase (from 15.5% to 25.3%). CONCLUSION: The inhibition of the P53/P21 pathway attenuated the senescence of NPC induced by SNPC-Exo.


Assuntos
Senescência Celular/fisiologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Exossomos/metabolismo , Núcleo Pulposo/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proliferação de Células , Células Cultivadas , Ratos , Ratos Sprague-Dawley
4.
Bioresour Technol ; 227: 1-6, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28012373

RESUMO

The composition of pyrolysis vapors obtained from alkali lignin pyrolysis with the additive of nickel formate was examined using the pyrolysis gas chromatography-mass spectrometry (Py-GC/MS). Characterization of bio-chars was performed using X-ray diffraction (XRD). Results showed that the nickel formate significantly increased liquid yield, simplified the types of alkali lignin pyrolysis products and increased individual component contents. The additive of nickel formate increased contents of alkylphenols and aromatics from alkali lignin pyrolysis. With an increase in temperature, a greater amount of the relative contents can be achieved. The nickel formate was thermally decomposed to form hydrogen, resulting in hydrodeoxygenation of alkali lignin during pyrolysis. It was also found that Ni is in favor of producing alkylphenols. The analysis based on the experimental result provided evidences used to propose reaction mechanism for pyrolysis of nickel formate-assisted alkali lignin.


Assuntos
Lignina/química , Níquel/química , Eliminação de Resíduos/métodos , Álcalis/química , Cromatografia Gasosa-Espectrometria de Massas , Difração de Raios X
5.
Knee Surg Sports Traumatol Arthrosc ; 24(8): 2541-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26423054

RESUMO

PURPOSE: To conduct a meta-analysis with randomized controlled trials (RCTs) published in full text to determine the effectiveness of patellar denervation (PD) in primary total knee arthroplasty (TKA). METHODS: Literature search was performed in PubMed, Embase, Web of Science and Cochrane Library for information from the earliest date of data collection to February 2015. RCTs comparing the benefits and risks of PD with those of no patellar denervation (NPD) in primary TKAs were included. Statistical heterogeneity was quantitatively evaluated by X(2) test with the significance set P < 0.10 or I (2) > 50 %. RESULTS: Six RCTs consisting of 751 patients were included. The incidences of AKP in PD group and NPD group were 38.3 % (90/235) and 46.3 % (107/231), respectively. Meta-analysis showed significant prevention effect of PD on the incidence of AKP (OR 0.65; 95 % CI 0.42, 1.00; P = 0.05) without significant heterogeneity (I (2) = 44 %, P = 0.15). Our results also indicated that PD was significantly associated with better American Knee Society knee (WMD = 2.50; 95 % CI 0.34, 4.67; P = 0.02) and functional scores (WMD = 4.07; 95 % CI 1.34, 6.80; P = 0.0003) and range of motion (ROM) (WMD = 4.27; 95 % CI 1.95, 6.60; P = 0.0003) compared with NPD. However, there was no significant difference between the two groups no matter in Oxford knee score, patellar score or visual analogue scale at any other time. Complications and revisions did not differ significantly between the two groups. CONCLUSION: This meta-analysis showed that PD in TKAs without patellar resurfacing, compared with NPD, could prevent the incidence of post-operative AKP and improve clinical outcome in KSS and post-operative ROM. Based on the above results, PD was a safe procedure with no significant complications and revision or re-operations. LEVEL OF EVIDENCE: Therapeutic study, Level II.


Assuntos
Artralgia/epidemiologia , Artroplastia do Joelho/métodos , Denervação/métodos , Osteoartrite do Joelho/cirurgia , Dor Pós-Operatória/epidemiologia , Patela/inervação , Humanos , Incidência , Articulação do Joelho/cirurgia , Medição da Dor , Patela/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Amplitude de Movimento Articular , Reoperação , Resultado do Tratamento , Escala Visual Analógica
6.
Waste Manag ; 34(12): 2603-10, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25223439

RESUMO

This work was aimed at improving the pyrolysis oil quality of waste rubber by adding larch sawdust. Using a 1 kg/h stainless pyrolysis reactor, the contents of sawdust in rubber were gradually increased from 0%, 50%, 100% and 200% (wt%) during the pyrolysis process. Using a thermo-gravimetric (TG) analyzer coupled with Fourier transform infrared (FTIR) analysis of evolving products (TG-FTIR), the weight loss characteristics of the heat under different mixtures of sawdust/rubber were observed. Using the pyrolysis-gas chromatography (GC)-mass spectrometry (Py-GC/MS), the vapors from the pyrolysis processes were collected and the compositions of the vapors were examined. During the pyrolysis process, the recovery of the pyrolysis gas and its composition were measured in-situ at a reaction temperature of 450 °C and a retaining time of 1.2s. The results indicated that the efficiency of pyrolysis was increased and the residual carbon was reduced as the percentage of sawdust increased. The adding of sawdust significantly improved the pyrolysis oil quality by reducing the polycyclic aromatic hydrocarbons (PAHs) and nitrogen and sulfur compounds contents, resulting in an improvement in the combustion efficiency of the pyrolysis oil.


Assuntos
Biocombustíveis/análise , Incineração/métodos , Resíduos Industriais/análise , Borracha/química , Madeira/química , Cromatografia Gasosa-Espectrometria de Massas , Larix/química , Melhoria de Qualidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Madeira/análise
7.
Exp Ther Med ; 6(4): 863-867, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24137279

RESUMO

Contrast-induced nephropathy (CIN) is a complex syndrome of acute kidney injury that follows exposure to intravascular contrast media. Although a series of preventive measures have been developed, CIN remains a major challenge encountered in elderly patients by interventional cardiologists. No data are currently available concerning the potential effects of the combined use of hydration and alprostadil in the prevention of CIN following percutaneous coronary intervention (PCI) in elderly patients. Therefore, the aim of the present study was to investigate the ability of a combination of hydration and alprostadil to prevent CIN following PCI in elderly patients. From June 1, 2010 to January 31, 2012, 85 elderly patients undergoing PCI were included in the present study. The included patients were randomly allocated into three groups: the control (22 cases), hydration (28 cases) and hydration + alprostadil (35 cases) group. Serum creatinine (SCr) levels were measured prior to PCI and then daily for 3 days following PCI. Creatinine clearance (Ccr) was also calculated. Following investigation of the incidence of CIN, a significant decline in Ccr was observed in the control group but not in the hydration + alprostadil group after PCI. The reduction in the level of Ccr from baseline in the hydration + alprostadil group was the smallest among the three groups. Moreover, the highest incidence of CIN was in the control group (6 cases, 27.27%), followed by the hydration group (3 cases, 10.71%) and the hydration + alprostadil group (1 case, 2.86%). Therefore, the combined use of hydration and alprostadil significantly reduces the incidence of CIN in elderly patients undergoing PCI. Hydration and alprostadil are suggested to act synergistically to protect renal function. In conclusion, the combined use of hydration and alprostadil is more effective in the prevention of CIN in elderly patients undergoing PCI compared with hydration alone.

8.
Oncol Lett ; 6(2): 612-616, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24137380

RESUMO

Percutaneous transluminal angioplasty using balloon catheters for Budd-Chiari syndrome (BCS) and transcatheter arterial chemoembolization (TACE) for unresectable hepatocellular carcinoma (HCC) have become increasingly accepted as alternative therapeutic modalities. However, few studies have investigated the clinical efficacy of combining percutaneous microwave ablation with angioplasty for patients with BCS complicated by HCC. In the present study, a safe and effective method for treating BCS associated with HCC is presented. Color Doppler ultrasonography, magnetic resonance imaging (MRI), computed tomography (CT), inferior venacavography, hepatic arteriogram and cytological examinations were used for the diagnosis. A KY2000 microwave system with an emission of 915 MHz was also employed for the treatment. Two patients with BCS associated with HCC that were administered different adjuvant drug treatments underwent percutaneous transluminal angioplasty and percutaneous microwave ablation successfully, with no treatment-related complications. Combining angioplasty with percutaneous microwave ablation may represent an alternative method for the treatment of BCS associated with HCC.

9.
Phytomedicine ; 20(10): 787-96, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23639192

RESUMO

Puerarin, the main isoflavone glycoside found in the Chinese herb radix of Pueraria lobata (Willd.) Ohwi, has received increasing attention because of its possible role in the prevention of osteoporosis. Previously, we showed that puerarin could inhibit the bone absorption of osteoclasts and promote long bone growth in fetal mouse in vitro. Further study confirmed that puerarin stimulated proliferation and differentiation of osteoblasts in rat. However, the mechanisms underlying its actions on human bone cells have not been well defined. Here we show that puerarin increases proliferation and differentiation and opposes cisplatin-induced apoptosis in human osteoblastic MG-63 cells containing two estrogen receptor (ER) isoforms. Puerarin promotes proliferation by altering cell cycle distribution whereas puerarin-mediated survival may be associated with up-regulation of Bcl-xL expression. Treatment with the ER antagonist ICI 182,780 abolishes the above actions of puerarin on osteoblast-derived cells. Using small interfering double-stranded RNA technology, we further demonstrate that the effects of puerarin on proliferation, differentiation and survival are mediated by both ERα and ERß. Moreover, we also demonstrate that puerarin functions at least partially through activation of MEK/ERK and PI3K/Akt signaling. This agent also shows much weaker effect on breast epithelial cell growth than that of estrogen. Therefore, puerarin will be a promising agent that prevents or retards osteoporosis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Isoflavonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/fisiologia , Fosfatase Alcalina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Colágeno/metabolismo , Feminino , Humanos , Isoflavonas/uso terapêutico , Sistema de Sinalização das MAP Quinases/fisiologia , Osteoblastos/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(4): 944-8, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22715758

RESUMO

The weight-loss character and gas evolution rule of larch wood at different heating rates were investigated by TG-FTIR (thermogravimetric analyzer coupled to a Fourier transform infrared spectrometer), and the results were compared with those of larch wood model-component mixture. The main weight-loss area of larch wood was wider than larch wood model-component mixture, and the residual char yield of larch wood (18.97%) was lower than larch wood model-component mixture (29.83%). During the pyrolysis process, the activation energy of larch wood model-component mixture was higher than the larch wood's in the low-temperature region, but there was little difference between the two segments in high temperature region. Larch wood came through several stages of water extraction, main component decomposition, charring during its pyrolysis process, and gas precipitation mainly happening at near 375 degrees C. The order of main gas products generated from the larch wood pyrolysis reaction was CO2 > H2O > CH4 > CO, and the gas product yield was significantly increased when the heating rate increased. The larch wood model-component mixture had the similar basic rules of producing gas to larch wood, but the former had relatively higher precipitation density than the latter.

11.
Arch Pharm Res ; 32(9): 1211-4, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19784575

RESUMO

A new hopane type pentacyclic triterpenoid, 2-hydroxydiplopterol (1) has been isolated from the metabolites produced by the halotolerant fungal strain Aspergillus variecolor B-17. The structure of 1 was determined by spectroscopic methods and single crystal X-Ray diffraction analysis. 2-Hydroxydiplopterol (1) exhibited cytotoxicity against K562 cells with an IC50 value of 22 microM.


Assuntos
Antineoplásicos/química , Aspergillus/metabolismo , Triterpenos Pentacíclicos/química , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Cristalografia por Raios X , Humanos , Células K562 , Leucemia P388/tratamento farmacológico , Camundongos , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/farmacologia
13.
J Nat Prod ; 71(6): 985-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18505285

RESUMO

Three new diketopiperazine alkaloids, 6-methoxyspirotryprostatin B (1), 18-oxotryprostatin A (2), and 14-hydroxyterezine D (3), with an oxaspiro[4.4]lactam moiety, 14-norpseurotin A (4), and the 29-nordammarane triterpenoid 6beta,16beta-diacetoxy-25-hydroxy-3,7-dioxy-29-nordammara-1,17(20)-dien-21-oic acid (5), as well as 12 known compounds (6- 17), were isolated from the ethyl acetate extract of a marine-derived fungal strain, Aspergillus sydowi PFW1-13. The structures of compounds 1- 5 were elucidated by comprehensive spectroscopic analysis. Compounds 1- 3 exhibit weak cytotoxicity against A-549 cells, with IC 50 values of 8.29, 1.28, and 7.31 microM, respectively. Compound 1 also shows slight cytotoxicity against HL-60 cells, with an IC 50 value of 9.71 microM. Compounds 4 and 5 display significant antimicrobial activities against Escherichia coli, Bacillus subtilis, and Micrococcus lysoleikticus with MICs of 3.74, 14.97, and 7.49 microM and 10.65, 5.33, and 10.65 microM, respectively.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Aspergillus/química , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/farmacologia , Compostos de Espiro/isolamento & purificação , Compostos de Espiro/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antibacterianos/química , Antineoplásicos/química , Bacillus subtilis/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/efeitos dos fármacos , Células HL-60 , Humanos , Alcaloides Indólicos/química , Testes de Sensibilidade Microbiana , Micrococcus/efeitos dos fármacos , Estrutura Molecular , Compostos de Espiro/química , Triterpenos/química
14.
Chem Biodivers ; 4(12): 2913-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18081101

RESUMO

During our search for novel antitumor lead compounds from microorganisms living under extreme conditions, three novel alkaloids, variecolortides A-C (1-3), were isolated from the mycelia of the halotolerant fungal strain Aspergillus variecolor B-17. The new compounds were found to share an unprecedented 'spiro-anthronopyranoid diketopiperazine' structure, with a stable hemiaminal function, as corroborated by in-depth NMR-spectroscopic and mass-spectrometric analyses, as well as by a single-crystal X-ray analysis of 1. All compounds were shown to exhibit weak cytotoxic and antioxidant activities.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Aspergillus/química , Resistência a Medicamentos/efeitos dos fármacos , Compostos Macrocíclicos/química , Sais/farmacologia , Compostos de Espiro/química , Alcaloides/toxicidade , Aspergillus/classificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Compostos Macrocíclicos/toxicidade , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Neoplasias/patologia , Compostos de Espiro/toxicidade
15.
J Nat Prod ; 70(10): 1558-64, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17896816

RESUMO

Twelve new compounds, variecolorins A-L ( 1- 12), together with eleven known analogues ( 13- 23) were isolated from the broth of a halotolerant fungus, Aspergillus variecolor. The structures of compounds 1- 12 were determined by chemical and spectroscopic methods. Compounds 1- 11, 13- 15, and 20- 23 exhibited weak radical scavenging activity against DPPH, with IC 50 values from 43 to 103 microM. The new compounds 1- 12 all were essentially nontoxic against the P388, HL-60, BEL-7402, and A-549 cell lines with IC 50 values from 70 to 260 microM.


Assuntos
Alcaloides/isolamento & purificação , Aspergillus/química , Sequestradores de Radicais Livres/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Animais , Compostos de Bifenilo , China , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Concentração Inibidora 50 , Estrutura Molecular , Picratos/farmacologia , Salinidade
16.
Arch Pharm Res ; 30(7): 816-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17703731

RESUMO

Two isocoumarin derivatives, stoloniferol A (1) and B (2), a known 5alpha, 8alpha-epidioxy-23-methyl-(22E, 24R)-ergosta-6, 22-dien-3beta-ol (3), and a known dihydrocitrinone (4) were isolated from the ethyl acetate extract of the sea squirt-derived fungus, Penicillium stoloniferum QY2-10, and a halophilic fungus, Penicillium notatum B-52, respectively. Their structures were elucidated by spectroscopic methods and optical rotation. The stereochemistry of 2 was determined on the basis of different NOE experiments and chemical transformation. Compound 3 showed cytotoxicity against P388 cells, with an IC50 value of 4.07 microM.


Assuntos
Antineoplásicos/isolamento & purificação , Isocumarinas/isolamento & purificação , Penicillium chrysogenum/química , Urocordados/microbiologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Concentração Inibidora 50 , Isocumarinas/química , Isocumarinas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Penicillium/química , Penicillium/isolamento & purificação , Penicillium chrysogenum/isolamento & purificação , Água do Mar
17.
Hepatol Res ; 37(5): 389-96, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17441812

RESUMO

AIM: To investigate the roles of epigenetic and genetic alterations of the phosphatase and tensin homologue on chromosome 10 gene (PTEN) in carcinogenesis and the development of hepatocellular carcinomas (HCC). METHODS: A total of 56 cases of HCC tissues and six liver cell lines were studied for the expression of PTEN by immunohistochemistry and Western blot analysis. The PTEN gene mutations in exon5 and exon8 were detected by a combination of single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. Methylation-specific PCR (MSP) was used to identify PTEN promoter methylation. RESULTS: Of the 56 cases of HCC, 24 (42.9%) expressed the PTEN protein. All surrounding liver tissues of the hepatoma (32 cases) were positive for PTEN. Of the six cell lines, three liver cancer cell lines showed a low expression of PTEN. Five mutations of 56 HCC samples were detected. All of them were located at intron4. No mutation was found in exon5 and exon8. After MSP analysis, we found nine cases of PTEN promoter methylation in 56 specimens (16.1%). However, no CpG island of PTEN was found to be methylated in all six liver cell lines. CONCLUSION: The level of PTEN protein was altered in part of the HCC. The downregulation of PTEN expression may not be mainly associated with the PTEN mutations, but partly due to PTEN promoter methylation and other epigenetic regulation.

18.
Zhonghua Bing Li Xue Za Zhi ; 35(8): 467-72, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17069699

RESUMO

OBJECTIVE: To study mutations of tumor suppressor gene PTEN in human hepatocellular carcinomas and its effects on the proliferation and apoptosis of hepatocellular carcinoma cell line HHCC. METHODS: (1) PCR-SSCP and sequence analysis were used to detect the mutations of the 5th and 8th exon of PTEN in 42 cases of human primary hepatocellular carcinoma. (2) Eukaryotic expression vectors of the wild-type (pEGFP-wt-PTEN) and the mutant type (pEGFP-PTEN, G129R) of PTEN were constructed. Lipofectamine 2000 mediated gene transfection was used to transfect hepatocellular carcinoma cell line HHCC, in which the PTEN protein is not expressed. Culture medium containing G418 was used to select stable transfectants. MTT colorimetry was used to analyze the proliferation ability of selected cell lines. Naive HHCC cells and HHCC cells transfected with empty vector (pEGFP-C1) served as controls. (3) TNF-alpha was used to induce apoptosis of selected cell clones. RESULTS: (1) Point mutation involving the 5th exon of PTEN was detected in 4 of 42 primary hepatocellular carcinomas. (2) Compared with the control groups, the proliferation of hepatocellular carcinoma cells was significantly inhibited by the transfection of wild-type PTEN gene, while the transfection with mutant PTEN construct did not significantly change the proliferation. (3) The apoptosis indices of cells transfected with the wild-type and the mutant PTEN genes were 13.8% and 8.1% respectively. Compared with the control, the apoptosis index of HHCC cell transfected by the wild type PTEN was significantly lower (P < 0.05). There were no significant differences between HHCC cells transfected with mutated PTEN gene and the control (P > 0.05). The expression of internal 473-phosphorylated Akt of HHCC was weak, but was enhanced when the cells treated with TNF-alpha. However, it was down regulated by the wild type PTEN. CONCLUSIONS: (1) First time report that PTEN mutations can be found in 9.5% human primary hepatocellular carcinomas. (2) The expression of the wild-type PTEN can suppress the proliferation of HHCC cells, and such suppression was lost when PTEN gene was mutated. (3) PTEN inhibition of the proliferation and the enhancement of apoptosis of hepatocellular carcinoma cells is likely related to a down-regulation of the TNF-alpha induced activation of protein kinase Akt pathway.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Mutação , PTEN Fosfo-Hidrolase/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Sequência de Bases , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Análise Mutacional de DNA , Citometria de Fluxo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Microscopia de Fluorescência , Dados de Sequência Molecular , PTEN Fosfo-Hidrolase/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/farmacologia
19.
World J Gastroenterol ; 11(23): 3498-503, 2005 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-15962362

RESUMO

AIM: To investigate the role of overexpression of Bax in apoptotic pathways and the response of human hepatocellular cancer (HCC)-9204 cells to cell death induced by adriamycin. METHODS: The whole length of Bax cDNA was transfected into human HCC-9204 cells by the method of lipofectamine transfection. An inducible MT-II regulatory system was constructed, which allowed controlled expression of protein upon addition of ZnSO4 (100 micromol/L) as an external inducer. Stable transfecting inducible expression vector containing Bax gene was performed. Expression of Bax in protein was analyzed by immunohistochemistry and Western blotting. TUNEL and flow cytometry were used to assess the effect of Bax on apoptosis. Colony assay and tetrazolium blue (MTT) assay were used to evaluate the difference in drug sensitivity of HCC-9204 cells after Bax-transfection. RESULTS: Immunohistochemistry and Western blotting demonstrated that the expression of Bax protein markedly increased in Bax-transfected cells 4 h after the addition of ZnSO4. Bax positive signal was frequently found on the cytoplasm and perinuclear region of HCC-9404 cells, and there was ectopic expression in cells with marked condensation of chromatin and cytoplasm (apoptotic cells). Apoptotic index significantly increased in Bax-transfected HCC-9204/Bax cells (3.6 vs 27.2, 4.2 vs 32.3, P<0.05). Flow cytometry analysis showed a significant sub-G1 peak and apoptosis in 15.4% HCC-9204/Bax cells 24 h after treatment. Furthermore, colony survival rate decreased from 66% (HCC-9204/pMD) to 45% (HCC-9204/Bax) 2 d after ADR withdrawal. MTT assay result showed that the effects of Bax on cell viability following ADR exposure were significant as compared to the vehicle-transfected HCC-9204/pMD cells (21% vs 44%, P<0.01). CONCLUSION: Overexpression of Bax not only induces apoptosis, but also sensitizes HCC-9204 cells to cell death induced by adriamycin.


Assuntos
Morte Celular/efeitos dos fármacos , Doxorrubicina/toxicidade , Antineoplásicos/toxicidade , Apoptose/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Transfecção
20.
Ai Zheng ; 24(2): 129-34, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15694019

RESUMO

BACKGROUND & OBJECTIVE: apr-1 was cloned by improved polymerase chain reaction (PCR)-based subtractive hybridization from all-trans retinoic acid (ATRA)-induced apoptotic leukemia HL-60 cells in 1999. Preliminary results showed that apr-1 might be an apoptosis-related gene (GenBank ID: NM_014061). This study was to explore the background of apr-1 through gene cloning, bioinformatic analysis, and subcellular locating. METHODS: The cDNA encoding Apr-1 was amplified by reverse transcription-PCR (RT-PCR), and sequenced. Open reading frame (ORF) of apr-1 was analyzed with ORF finder software. Chromosome locus was defined by genome blast software. Conserved domains of amino acids were analyzed by protein blast software. Align (Cluster W) software in Vector NTI software package was used to analyze homogeneous genes (or proteins), and to draw the Phylogenetic Tree. Subcellular localization of apr-1 was performed. RESULTS: apr-1 was mapped to chromosome Xp11.22 with the ORF locating in 1 exon. Two MAGE conserved domains were found in Apr-1. Apr-1 shared homology with MAGE-A1, MAGE-B1, MAGE-C1, MAGE-D1, and Necdin. Phylogenetic analysis showed that Apr-1 was more closely related to MAGE-D1 and Necdin. Gene products of apr-1 were located in the nuclei of eukaryocytes. CONCLUSIONS: apr-1 is a member of MAGE family, and might belong to type II MAGE genes.


Assuntos
Antígenos de Neoplasias/genética , DNA Complementar/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Núcleo Celular/química , Chlorocebus aethiops , Clonagem Molecular , Sequência Conservada , Células HL-60 , Humanos , Proteínas Associadas aos Microtúbulos/análise , Dados de Sequência Molecular , Proteínas de Neoplasias/análise , Fases de Leitura Aberta , Filogenia , Alinhamento de Sequência , Cromossomo X
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