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1.
Environ Sci Pollut Res Int ; 31(4): 6067-6081, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38147243

RESUMO

Climate change is an important issue for cities today and in the future. At present, China has a large population and complex climate conditions, and cities are also vulnerable to the adverse effects of climate change (Tian, Environ Sustain Dev 6: 153-155 2020). Three-dimensional greening can not only improve the green space system of a city but also have a far-reaching impact on the ecology, image, and economic benefits of a city. Therefore, the study of urban three-dimensional greening is an effective means to deal with climate change strategies. By exploring the influence of traditional greening and three-dimensional greening on Local Climate in Beilin District of Xi'an, Shaanxi Province, the mechanism of three-dimensional greening on urban ecological environment was discussed, and the ecological theory, urban three-dimensional greening theory, and urban local climate zone (LCZ) were referred to. Based on the methods of national climate monitoring, ENVI-met simulation, and field independent measurement, this paper selected a research sample site in the east section of Jianshe Road, Beilin District, Xi'an City, Shaanxi Province, China, and applied ENVI-met software to simulate the thermal stress relationship among building exterior surfaces, plants, and air in the street; quantified the overall ecology of the area; and used measuring instruments. The influence of different types of greening in the base on the site temperature, humidity, CO2 (carbon dioxide) concentration, wind speed, and other climate factors data was, respectively, measured and analyzed. The grid analysis was used to compare the traditional greening and three-dimensional greening, then the numerical differences of each impact factor were sorted out, and the effect of three-dimensional greening on the improvement of urban ecological environment was discussed by analyzing the climate factors with greater impact. The results show that (1) three-dimensional greening plus traditional greening is the most beneficial mode; (2) in the same environment, according to the parameter of 1.5 m from the ground in the model environment, it can be seen that the temperature of the space treated with three-dimensional greening of buildings is reduced by 3.5-3.6 â„ƒ compared with the control group, the relative humidity is different by 7-8%, the CO2 concentration is reduced by about 5%, and the spatial wind speed is relatively small. (3) When the urban green coverage rate is more than 40%, the improvement of temperature is more obvious, if it reaches 50%, the cool phenomenon in summer can be fundamentally changed. From the perspective of human perception, the PMV index increased by 0.27 on average. This paper discusses and analyzes the three-dimensional greening of urban streets in Beilin District, Xi'an City, Shaanxi Province, China, and studies its influence on urban ecology to different degrees. The conclusions are as follows: Different types of greening have different degrees of influence on urban climate. Meanwhile, the experimental results of this paper show that in cities like Xi'an, Shaanxi Province, China, where summer is hot, adding three-dimensional greening to traditional street greening can significantly improve the environmental microclimate, which is an effective means to cope with climate change, improve the site environment, and stabilize the urban ecosystem.


Assuntos
Dióxido de Carbono , Ecossistema , Humanos , Mudança Climática , Cidades , Temperatura Baixa , China
2.
J Gastrointest Oncol ; 14(5): 2006-2017, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969842

RESUMO

Background: Esophageal cancer (EC) is a highly lethal malignancy with a grim prognosis and high mortality rates, primarily treated through surgery and radiotherapy. Herbal remedies are emerging as complementary approaches in cancer therapy. Here, we explore the potential therapeutic benefits of Chinese medicine raw Pinellia ternata (RP) in EC using web-based pharmacological methods and cellular experiments. Methods: The chemical components of RP were obtained by data mining via searches of the systematic pharmacology database, analysis platform, and literature on traditional Chinese medicine (TCM). The properties of the main components of RP were calculated using Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The potential targets of the components were mined and collected through multiple databases, and the relevant potential targets of efficacy were imported into Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database to obtain protein interactions. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway enrichment analysis of the potential targets were performed through Metascape. A target-pathway network was established using Cytoscape, and topological analysis was performed on the network so as to obtain the relevant targets and pathways of RP in the treatment of EC. The inhibitory effect of RP on human EC cells was verified by cell experiments. Results: Thirteen bioactive components of RP were screened, 87 related targets were obtained by construction, and 68 co-targets were obtained after taking intersection with EC related genes. The results of the protein-protein interaction (PPI) network analysis of the targets showed that the pharmacodynamic targets of hemicellulose might be closely related to the signaling pathways such as PI3K-Akt, FOS/JUN, and HIF-1. Meanwhile, GO and KEGG enrichment analysis showed that PI3K-Akt was also significantly enriched. The in vitro cellular experiments further indicated that raw hemicrania could inhibit EC through the PI3K-Akt signaling pathway. Conclusions: The pharmacodynamic mechanism of RP in the treatment of esophageal carcinoma was preliminarily revealed, which provided ideas and the basis for further experimental study of RP in the treatment of esophageal carcinoma.

3.
Adv Sci (Weinh) ; 10(10): e2300282, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36755201

RESUMO

Despite the success of small interfering RNA (siRNA) in clinical settings and its potential value in human immunodeficiency virus (HIV) therapy, the rapid clearance and absence of precise delivery to target cells still hinder the therapeutic effect of siRNA. Herein, a new system, which can escape immune recognition, has HIV-1 neutralizing capacity, and the ability to deliver siRNA specifically into HIV-1-infected cells, is constructed by functionalizing siRNA delivery lipid nanoparticles with the lymphocyte membrane and 12p1. The constructed system is shown to escape uptake by the mononuclear phagocyte system. The constructed system exhibits strong binding ability with gp120, thus displaying distinguished neutralizing breadth and potency. The constructed system neutralizes all tested HIV-1 pseudotyped viruses with a geometric mean 80% inhibitory concentration (IC80) of 29.75 µg mL-1 and inhibits X4-tropic HIV-1 with an IC80 of 64.20 µg mL-1 , and R5-tropic HIV-1 with an IC80 of 16.39 µg mL-1 . The new system also specifically delivers siRNA into the cytoplasm of HIV-1-infected cells and exhibits evident gene silencing of tat and rev. Therefore, this new system can neutralize HIV-1 and deliver siRNA selectively into HIV-1-infected cells and may be a promising therapeutic candidate for the precise therapy of HIV.


Assuntos
Infecções por HIV , HIV-1 , Nanopartículas , Humanos , HIV-1/genética , HIV-1/metabolismo , RNA Interferente Pequeno/metabolismo , Linfócitos , Infecções por HIV/terapia , Infecções por HIV/genética
5.
Pharmaceutics ; 14(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36145566

RESUMO

As one of the most frequent complications of critical illness, acute lung injury (ALI) carries a high risk of clinical morbidity and mortality. Cepharanthine (CPA) has significant anti-inflammatory activity, however, due to poor water solubility, low bioavailability, and short half-life, it fails to provide effective clinical management measures. Here, we explored the flexibility of an erythrocyte-anchoring strategy using CPA-encapsulated chitosan-coating nanoparticles (CPA-CNPs) anchored onto circulating erythrocytes for the treatment of ALI. CPA-CNPs adhered to erythrocytes successfully (E-CPA-CNPs) and exhibited high erythrocyte adhesion efficiency (>80%). Limited toxicity and favorable biocompatibility enabled further application of E-CPA-CNPs. Next, the reticuloendothelial system evasion features were analyzed in RAW264.7 macrophages and Sprague-Dawley rats. Compared with bare CPA-CNPs, erythrocyte-anchored CNPs significantly decreased cellular uptake in immune cells and prolonged circulation time in vivo. Notably, the erythrocyte-anchoring strategy enabled CNPs to be delivered and accumulated in the lungs (up to 6-fold). In the ALI mouse model, E-CPA-CNPs attenuated the progression of ALI by inhibiting inflammatory responses. Overall, our results demonstrate the outstanding advantages of erythrocyte-anchored CPA-CNPs in improving the pharmacokinetics and bioavailability of CPA, which offers great promise for a lung-targeted drug delivery system for the effective treatment of ALI.

6.
Int J Pharm ; 619: 121719, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35390488

RESUMO

Recent studies have demonstrated that ivermectin (IVM) exhibits antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus of coronavirus disease 2019 (COVID-19). However, the repurposing of IVM for the treatment of COVID-19 has presented challenges primarily due to the low IVM plasma concentration after oral administration, which was well below IC50. Here, a red blood cell (RBC)-hitchhiking strategy was used for the targeted delivery of IVM-loaded nanoparticles (NPs) to the lung. IVM-loaded poly (lactic-co-glycolic acid) (PLGA) NPs (IVM-PNPs) and chitosan-coating IVM-PNPs (IVM-CSPNPs) were prepared and adsorbed onto RBCs. Both RBC-hitchhiked IVM-PNPs and IVM-CSPNPs could significantly enhance IVM delivery to lungs, improve IVM accumulation in lung tissue, inhibit the inflammatory responses and finally significantly alleviate the progression of acute lung injury. Specifically, the redistribution and circulation effects were related to the properties of NPs. RBC-hitchhiked cationic IVM-CSPNPs showed a longer circulation time, slower accumulation and elimination rates, and higher anti-inflammatory activities than RBC-hitchhiked anionic IVM-PNPs. Therefore, RBC-hitchhiking provides an alternative strategy to improve IVM pharmacokinetics and bioavailability for repurposing of IVM to treat COVID-19. Furthermore, according to different redistribution effects of different NPs, RBC-hitchhiked NPs may achieve various accumulation rates and circulation times for different requirements of drug delivery.


Assuntos
Tratamento Farmacológico da COVID-19 , Nanopartículas , Eritrócitos , Humanos , Ivermectina , Pulmão , SARS-CoV-2
7.
Mol Ther Nucleic Acids ; 27: 349-362, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35024246

RESUMO

Despite the success of small interfering RNAs (siRNAs) in clinical settings, their fast clearance and poor delivery efficiency to target cells still hinder their therapeutic effect. Herein, a new treatment system was constructed by combining thermosensitive liposomes with the macrophage membrane, tumor-targeting cyclic Arg-Gly-Asp peptide, a cell-penetrating peptide, and thermotherapy. The constructed system was found to be thermosensitive and stable; the proteins were inherited from the macrophage membrane. This new system combined with thermotherapy displayed the least uptake by macrophages, the greatest uptake by HepG2 cells, the most obvious HepG2 cell apoptosis, and the strongest inhibition of Bcl-2 mRNA and Bcl-2 protein in HepG2 cells. Moreover, 24 h after system administration in tumor-bearing mice, the most prominent distribution of siRNA was observed in tumors, while almost no siRNA was found in other organs. The strongest inhibition of Bcl-2 mRNA, Bcl-2 protein, and tumors was found in mice that had received the proposed system. In summary, when using the constructed system both in vitro and in mice, less uptake by the reticuloendothelial system, greater accumulation in tumor cells, and improved therapeutic efficacy were observed. Therefore, this new system can deliver siRNA selectively and efficiently, and it is a promising therapeutic candidate for precise tumor-targeted therapy.

8.
Acta Biomater ; 140: 573-585, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34958970

RESUMO

Traumatic brain injury (TBI) is known to activate poly (ADP-ribose) polymerase (PARP-1), which leads to pronounced negative effects on mitochondrial DNA (mt-DNA) repair and function. Notably, PARP inhibitors are reported to be beneficial in experimental models of TBI. A targeting strategy for the delivery of neuronal mitochondria-specific PARP inhibitors could result in a greater neuroprotective effect and be a safer approach for TBI treatment. In the present study, we developed the PARP inhibitor olaparib (Ola) as a model drug and devised red blood cell (RBC)-coated nanostructured lipid carriers (RBCNLCs) co-modified with C3 and SS31 peptide (C3/SS31-RBCNLCs) for brain neuronal mitochondria-targeting. Our results indicated that biomimetic nanosystems have the physical and chemical properties of the NLCs, as well as the biological properties of RBC. A high concentration of Ola delivered into brain mitochondria by C3/SS31-RBCNLCs-Ola effectively improved mitochondrial function and prevented neuronal cell death caused by excessive activation of injury-induced mitochondrial PARP (mt-PARP) in vitro and in vivo. Taken together, the results of this study support the preclinical feasibility of developing highly effective nano-drugs as part of precision medicine for TBI. STATEMENT OF SIGNIFICANCE: TBI-induced neuronal mitochondria DNA damage activates Poly(ADP-ribose) Polymerase (PARP1) which leads to a pronounced negative effect on mitochondrial DNA repair and mitochondrial function. In recent years, PARP inhibitors showed strong benefits in experimental models of TBI, more importantly PARP inhibitors specially target neuronal mitochondria may play a greater neuroprotective role and may be a safer approach for TBI treatment. Herein, we designed red blood cell (RBC) membrane-coated nanostructure lipid carriers dual-modified with C3 and SS31 (C3/SS31-RBCNLCs) to accomplish these objectives. After encapsulating Olaparib (Ola) as the model PARP inhibitor, the data demonstrated that C3/SS31-RBCNLCs, with brain neuronal mitochondria targeting, can reduce neuronal cell death and improve mitochondrial dysfunction triggered by mitochondrial PARP activation in vitro and in vivo.


Assuntos
Lesões Encefálicas Traumáticas , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Biomimética , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
9.
Hum Exp Toxicol ; 40(12_suppl): S753-S762, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34787501

RESUMO

Cigarette smoke (CS)-caused ferroptosis was involved in the pathogenesis of COPD, but the role of ferroptosis in lung epithelial injury and inflammation is not clear. Rats were treated with CS or CUR and BEAS-2B cells were exposed to CS extract (CSE), ferrostatin-1 (Fer-1), deferoxamine (DFO), or CUR to detect reactive oxygen species (ROS) accumulation, lipid peroxidation, iron overload, and ferroptosis-related protein, which were the characteristic changes of ferroptosis. Compared with the control group, CSE-treated BEAS-2B cells had more cell death, higher cytotoxicity, and lower cell viability. The infiltration of inflammatory cell around the bronchi in the CS group of rats was more than that in the normal group. Meanwhile, CSE/CS elevated the levels of interleukin-6 and tumor necrosis factor-α in BEAS-2B cells and bronchoalveolar lavage fluid of rats. Besides, accumulative ROS and depleted glutathione was observed in vitro. In BEAS-2B cells and lung tissues of rats, CSE/CS increased malondialdehyde and iron; down-regulated solute carrier family 7, glutathione peroxidase 4, and ferritin heavy chain levels; and up-regulated transferrin receptor level. These changes were rescued by pretreatment of Fer-1 or DFO in vitro, and mitigated by CUR in vitro and in vivo. Collectively, this study reveals that ferroptosis was involved in lung epithelial cell injury and inflammation induced by CS, and CUR may alleviate CS-induced injury, inflammation, and ferroptosis of lung epithelial cell.


Assuntos
Curcumina/farmacologia , Células Epiteliais/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nicotiana , Fumaça , Linhagem Celular , Humanos , Pulmão/citologia
10.
Pharm Dev Technol ; 26(6): 634-646, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33843423

RESUMO

A combination of doxorubicin (DOX) and small interfering RNA (siRNA) is proven effective for the reverse of multidrug resistance. However, rapid degradation and poor cellular internalization of siRNA hinder their synergistic action. To improve the combination effect, asparagine-glycine-arginine peptide (NGR) -modified nanobubbles (NBs) containing cell-penetrating peptide (CPP) decorated DOX and CPP decorated c-myc siRNA were constructed. Diameters of these NBs were about 245 nm and zeta potentials were about -3 mV. Encapsulation efficiencies (EE) of DOX exceeded 80%. Release of DOX could be triggered by ultrasound (US) since above 80% DOX was released from NBs after sonication while less than 5% DOX was discharged without treatment of US. These NBs were considered stable during 24 h since the decrease of particle size was no more than 10 nm, variances of EE were less than 5%, and changes of transmission (ΔT) were less than 3%. More drugs in formulation decorated with CPP and NGR were accumulated in the tumor when combined with sonication. The evident synergistic action of DOX, siRNA, NBs, and US was verified in mice with strong antitumor efficacy. Taken together, NGR-modified NBs containing CPP-DOX and CPP-siRNA are able to realize time- and spatial-controlled drug delivery and show potential application prospects.


Assuntos
Peptídeos Penetradores de Células/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Oligopeptídeos/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Nus , RNA Interferente Pequeno/genética , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologia
11.
PLoS One ; 16(4): e0250670, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909691

RESUMO

We developed a novel preparative method for nanoparticle albumin-bound (nab) paclitaxel with high drug loading, which was based on improved paclitaxel solubility in polyethylene glycol (PEG) and self-assembly of paclitaxel in PEG with albumin powders into nanoparticles. That is, paclitaxel and PEG were firstly dissolved in ethanol, which was subsequently evaporated under vacuum. The obtained liquid was then mixed with human serum albumin powders. Thereafter, the mixtures were added into phosphate-buffered saline and nab paclitaxel suspensions emerged after ultrasound. Nab paclitaxel was finally acquired after dialysis and freeze drying. The drug loading of about 15% (W/V) were realized in self-made nab paclitaxel, which was increased by approximately 50% compared to 10% (W/V) in Abraxane. Now this new preparative method has been authorized to obtain patent from China and Japan. The similar characteristics of self-made nab paclitaxel compared to Abraxane were observed in morphology, encapsulation efficiency, in vitro release, X-ray diffraction analysis, differential scanning calorimetry analysis, and circular dichroism spectra analysis. Consistent concentration-time curves in rats, biodistributions in mice, anti-tumor activities in mice, and histological transmutation in mice were also found between Abraxane and self-made nanoparticles. In a word, our novel preparative method for nab paclitaxel can significantly improve drug loading, obviously decrease product cost, and is considered to have potent practical value.


Assuntos
Paclitaxel Ligado a Albumina/química , Antineoplásicos/química , Nanopartículas/química , Paclitaxel Ligado a Albumina/metabolismo , Paclitaxel Ligado a Albumina/uso terapêutico , Animais , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Meia-Vida , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Tamanho da Partícula , Polietilenoglicóis/química , Ratos , Ratos Wistar , Distribuição Tecidual , Transplante Heterólogo
12.
Drug Deliv ; 27(1): 1412-1424, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33096947

RESUMO

The tumor-derived and transcatheter arterial chemoembolization (TACE) induced hypoxia microenvironment is closely related to the poor prognosis of hepatocellular carcinoma (HCC). In this study, hypoxia-activated prodrug TH-302 loaded poly(lactic-co-glycolic acid) (PLGA)-based TACE microspheres were prepared to treat HCC through localized and sustained drug delivery. TH-302 microspheres with three different sizes were fabricated by an oil-in-water emulsion solvent evaporation method and characterized by scanning electron microscopy (SEM), infrared spectra (IR), X-ray diffractometer (XRD), and drug release profiles. The in vitro antitumor potential was firstly evaluated in an HepG2 cell model under normoxic and hypoxic conditions. Then, a VX-2 tumor-bearing rabbit model was established and performed TACE to investigate the in vivo drug tissue distribution and antitumor efficiency of TH-302 microspheres. Blood routine examination and histopathological examinations were also conducted to evaluate the safety of TH-302 microspheres. TH-302 microspheres with particle size 75-100 µm, 100-200 µm, and 200-300 µm were prepared and characterized by sphere morphology and sustained drug release up to 360 h. Compared with TH-302, the microspheres exhibited higher cytotoxicity, cell apoptosis, and cell cycle S phase retardation in HepG2 cells under hypoxic conditions. The microspheres also displayed continuous drug release in the liver tissue and better anti-tumor efficiency compared with TH-302 injection and lipiodol. Meanwhile, no serious toxicity appeared in the duration of treatment. Therefore, TH-302 microspheres showed to be feasible and effective for TACE and hold promise in the clinical for HCC chemoembolization therapy.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Nitroimidazóis/administração & dosagem , Mostardas de Fosforamida/administração & dosagem , Animais , Antineoplásicos/metabolismo , Carcinoma Hepatocelular/metabolismo , Cateterismo , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Nitroimidazóis/metabolismo , Mostardas de Fosforamida/metabolismo , Coelhos
13.
Chem Commun (Camb) ; 50(69): 9936-8, 2014 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-25033417

RESUMO

A direct nitration of aromatic sulfonamides using sodium nitrite as the nitrating agent has been developed. The reaction shows typically mono-substitution selectivity and can be enlarged to the gram scale with good yield.

14.
Eur J Med Chem ; 64: 621-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23711769

RESUMO

Carbamate derivatives of 4ß-(1,2,3-triazol-1-yl)podophyllotoxin were synthesized by means of click chemistry, and their cytotoxicities against human cancer cell lines HL-60, A-549, HeLa, and HCT-8 were evaluated. Some compounds were more potent than the anticancer drug etoposide. 4'-O-Demethyl-4ß-[(4-hydroxymethyl)-1,2,3-triazol-1-yl]-4-deoxypodophyllotoxin cyclopentyl carbamate, the most potent compound, induced cell cycle arrest in the G2/M phase accompanied by apoptosis in A-549 cells. Furthermore, this compound inhibited the formation of microtubules in A-549 cells and caused the inhibition of DNA topoisomerase-II.


Assuntos
Antineoplásicos/farmacologia , Carbamatos/farmacologia , Podofilotoxina/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carbamatos/síntese química , Carbamatos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Células HeLa , Humanos , Estrutura Molecular , Podofilotoxina/química , Podofilotoxina/farmacologia , Relação Estrutura-Atividade
15.
Bioorg Med Chem Lett ; 23(13): 3780-4, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23711918

RESUMO

A series of dichloroplatinum(II) complexes of podophyllotoxin (PPT) were prepared, and their cytotoxicity against sensitive (A-549, HeLa, HCT-8, Hep-G2, K562) and resistant (ADM/K562) cell lines were evaluated. Complex cis-[4α-O-(2″,3″-diaminopropanoyl)-podophyllotoxin] dichloride platinum(II) (12) displayed most potent cytotoxicity with IC50 value in the range 0.071-2.98 µM. Complex 12 induces cell cycle arrest in the G2/M phase, and inhibits the formation of microtubules in HeLa cells. Furthermore, this complex exhibits potent DNA cleavage capabilities.


Assuntos
Antineoplásicos/farmacologia , Compostos Organoplatínicos/farmacologia , Podofilotoxina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Células Hep G2 , Humanos , Células K562 , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Relação Estrutura-Atividade
16.
Zhongguo Fei Ai Za Zhi ; 15(12): 689-93, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23249714

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) overexpression and mutations were existed in more than 40% of the lung cancer, and it's the one of molecular targets in clinical treatment. But the EGFR tyrosine kinase inhibitors (TKI)-resistance is becoming a challenging clinical problem as following the application of EGFR-TKIs, Gefitinib or Erlotinib. However, the mechanistic explanation for resistance in the some cases is still lacking. Here we researched the resistance mechanism of H1650 cells. METHODS: Using real-time RT-PCR to analyze the EGFR mRNA expression level in EGFR wild-type non-small cell lung cancer (NSCLC) cells; MTT analysis detected the cytotoxicity for NSCLC cells to Erlotinib; Western blot analysis examined the mutant situations and the downstream signaling protein phosphorylation level in EGFR-mutant NSCLC cells with the treatment of Erlotinib or/and PI3K inhibitor, LY294002. RESULTS: In the EGFR wild-type NSCLC cells, the expression level of EGFR mRNA varied dramatically and all the cells showed resistant to Erlotinib; In the EGFR-mutant cells, HCC827 and H1650 (the same activating-mutation type), HCC827 cells were Erlotinib-sensitive as well as H1650 demonstrated primary relative resistance. Western blot analysis showed the loss of PTEN and the p-AKT level was not inhibited with the treatment of Erlotinib or/and LY294002 in H1650 cells, while HCC827 cells were no PTEN loss and definitively decrease of p-AKT level. CONCLUSIONS: EGFR wild-type NSCLC cells were resistant to Erlotinib no matter of how EGFR mRNA expression level. EGFR-activating mutations correlated with responses to Erlotinib. The PTEN loss and activation of AKT signaling pathway contributed to Erlotinib resistance in EGFR-mutant NSCLC cell line H1650.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Mutação , Quinazolinas/farmacologia , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Cloridrato de Erlotinib , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Morfolinas/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
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