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1.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2643-2651, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35718482

RESUMO

Despite the development of HPV vaccines and screening programs, cervical cancer is still a serious threat to women's health. Early-stage cervical cancer is mainly treated by surgery. However, considering the serious complications after surgery, hyperthermia is recommended to enhance the effect of chemotherapy, retain the integrity of cervix, improve the treatment effect, which provides a therapeutic basis for the early treatment of cervical cancer. The photosensitive liposomes containing harmine and dye IR-780 were prepared by thin-film dispersion method and separated by Sephadex G-50 dextran gel column. The preparation conditions were optimized as the mass ratio of phospholipid to cholesterol membrane material being 8∶1 and that of drug to lipid being 1∶20. The results of HPLC showed that the encapsulation efficiency of harmine was 55.6%±0.18%. The prepared photosensitive liposomes were round and evenly distributed under transmission electron microscope, with the particle size of(125.2±0.62) nm determined by Marvin particle size analyzer and the Zeta potential of(-2.55±0.76) mV. Additionally, the photosensitive liposomes had the photothermal conversion efficiency, an important property of photothermal agent, of 27.1%±0.86%. The photosensitive liposomes stored at 4 ℃ showed stable encapsulation efficiency in the first 14 days without flocculation. The sulforhodamine B(SRB) assay was employed to determine the inhibitory effect of the liposomes on the proliferation of HeLa cells under near-infrared(NIR) irradiation or not, which showcased stronger inhibitory effect under NIR irradiation. The results of Transwell assay indicated that the prepared liposomes significantly inhibited the invasion and migration of HeLa cells in vitro. The findings of this study provide a basis for the treatment of cervical cancer with harmine.


Assuntos
Lipossomos , Neoplasias do Colo do Útero , Feminino , Harmina/farmacologia , Células HeLa , Humanos , Tamanho da Partícula , Neoplasias do Colo do Útero/tratamento farmacológico
2.
Front Pharmacol ; 12: 678203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248628

RESUMO

Cancer has the highest mortality in humans worldwide, and the development of effective drugs remains a key issue. Traditional Chinese medicine Saussurea involucrata (SI) exhibits a series of effects, such as anti-cancer, but the action mechanisms are still unclear. Here, systems pharmacology was applied to reveal its anti-cancer mechanism. First, we screened the active compounds of SI. Then, the compound-target network, target-disease network, and target-pathway network were constructed. DAVID was applied for GOBP analysis and KEGG pathway enrichment analysis on cancer-related targets. Seven potential compounds and 187 targets were identified. The target-disease classification network showed that compounds mainly regulated proteins related to cancer, nervous system diseases, and cardiovascular system diseases. Also, SI anti-tumor effect mainly associated with the regulation of NO production, angiogenesis, MAPK, and PKB from GOBP enrichment. Additionally, KEGG pathway enrichment indicated that targets involved in anti-inflammatory action, inhibiting angiogenesis and anti-proliferation or inducing apoptosis. Experimental validation showed that four active compounds could inhibit cell proliferation and promote apoptosis in A549 (except for kaempferol), PC-3, and C6 cells. This study not only provides experimental evidence for further research on SI in cancer treatment but also promotes the development of potential drugs of SI in modern medicine.

3.
Anal Chim Acta ; 878: 102-8, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-26002331

RESUMO

In the current study, we introduced a novel polystyrene/graphene (PS/G) composite nanofiber film for thin film microextraction (TFME) for the first time. The PS/G nanofiber film was fabricated on the surface of filter paper by a facile electrospinning method. The morphology and extraction performance of the resultant composite film were investigated systematically. The PS/G nanofiber film exhibited porous fibrous structure, large surface area and strong hydrophobicity. A new thin film microextraction-high performance liquid chromatography (TFME-HPLC) method was developed for the determination of six aldehydes in human exhaled breath condensates. The method showed high enrichment efficiency and fast analysis speed. Under the optimal conditions, the linear ranges of the analytes were in the range of 0.02-30 µmol L(-1) with correlation coefficients above 0.9938, and the recoveries were between 79.8% and 105.6% with the relative standard deviation values lower than 16.3% (n=5). The limits of quantification of six aldehydes ranged from 13.8 to 64.6 nmol L(-1). The established method was successfully applied for the quantification of aldehyde metabolites in exhaled breath condensates of lung cancer patients and healthy people. Taken together, the TFME-HPLC method provides a simple, rapid, sensitive, cost-effective, non-invasion approach for the analysis of linear aliphatic aldehydes in human exhaled breath condensates.


Assuntos
Aldeídos/análise , Testes Respiratórios/instrumentação , Grafite/química , Nanofibras/química , Poliestirenos/química , Microextração em Fase Sólida/instrumentação , Adsorção , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Humanos , Limite de Detecção , Nanofibras/ultraestrutura
4.
J Colloid Interface Sci ; 402: 284-90, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23651668

RESUMO

This work reports a study of protein adsorption and cell adhesion on binary self-assembled monolayers (SAMs) of alkanethiols with terminal perfluoroalkyl (PFA) and oligo(ethylene glycol) (OEG) chains in varying ratios. The surface chemistry of the SAMs was characterized by contact angle measurement, grazing angle infrared spectroscopy (GIR), X-ray photoelectron spectroscopy, and the effect on protein adsorption was investigated by surface plasmon resonance, GIR, and immunosorbent assay. Hela cell adhesion on these surfaces was also studied by fluorescence microscopy. Results reveal that, compared to OEG, PFA tended to be a higher fraction of the composition in SAM than in the assembly solution. More interestingly, the nearly 38% PFA SAM had a strong antifouling property whereas the 74% PFA SAM showed a high adsorption capacity to protein and cell. The binary PFA/OEG SAMs were favorable for maintaining the fibrinogen conformation, hence its high activity. The findings may have important implications for constructing PFA-containing surfaces with the distinct properties that is highly resistant or highly favorable toward protein adsorption and cell adhesion.


Assuntos
Proteínas Sanguíneas/química , Fluorocarbonos/química , Membranas Artificiais , Polietilenoglicóis/química , Adsorção , Animais , Bovinos , Adesão Celular , Células HeLa , Humanos , Propriedades de Superfície
5.
Eur J Oral Sci ; 115(1): 30-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17305714

RESUMO

High mobility group A2 (HMGA2) protein is a non-histone architectural transcription factor. Numerous studies have demonstrated that HMGA2 is exclusively expressed in the nucleus of embryonic, but not of terminally differentiated, cells, and aberrant expression of HMGA2 is associated with various benign tumors, including pleomorphic salivary adenoma. Herein, we report the use of a 4.5-kb enhancer/promoter region of the aquaporin-5 (AQP-5) gene to target HMGA2 transgene expression in the mouse salivary acinar cells as a model to investigate the biochemical and biological role of ectopic HMGA2 expression. The expression pattern was analyzed by microarray analyses to profile HMGA2-dependent salivary gene regulation. By using quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays, the expression of a cluster of genes involved in cytokine signaling, including Il7r, Il2rg, and Ptprc, was verified to be up-regulated in the salivary glands of AQP-5/HMGA2 mice. In concert, the expression of a cluster of genes, namely Ppara, Phyh, and Cidea, governing fatty acid and lipid metabolism, was confirmed to be down-regulated by HMGA2. Additionally, squamous carcinoma-like salivary tumors were observed in the AQP-5/HMGA2 transgenic mice, albeit at a low incidence. Our findings indicate that the AQP-5 promoter/enhancer-containing region is sufficient to target salivary-specific transgene expression and suggest novel roles for HMGA2 in salivary epithelial cells.


Assuntos
Aquaporina 5/genética , Regulação da Expressão Gênica , Proteína HMGA2/genética , Proteína HMGA2/fisiologia , Glândulas Salivares/metabolismo , Animais , Aquaporina 5/fisiologia , Carcinoma de Células Escamosas/genética , Elementos Facilitadores Genéticos/fisiologia , Perfilação da Expressão Gênica , Metabolismo dos Lipídeos/genética , Camundongos , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias das Glândulas Salivares/genética , Transdução de Sinais/genética
6.
Am J Physiol Cell Physiol ; 289(2): C444-54, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15788485

RESUMO

We recently showed that Etk/Bmx, a member of the Tec family of nonreceptor protein tyrosine kinases, promotes tight junction formation during chronic hypoxic exposure and augments normoxic VEGF expression via a feedforward mechanism. Here we further characterized Etk's role in potentiating hypoxia-induced gene expression in salivary epithelial Pa-4 cells. Using transient transfection in conditionally activated Etk (DeltaEtk:ER) cells, we demonstrated that Etk enhances hypoxia-response element-dependent reporter activation in normoxia and hypoxia. This Etk-driven reporter activation is ameliorated by treatment with wortmannin or LFM-A13. Using lentivirus-mediated gene delivery and small interfering RNA, we provided direct evidence that hypoxia leads to transient Etk and Akt activation and hypoxia-mediated Akt activation is Etk dependent. Northern blot analyses confirmed that Etk activation led to induction of steady-state mRNA levels of endogenous VEGF and plasminogen activator inhibitor (PAI)-1, a hallmark of hypoxia-mediated gene regulation. We also demonstrated that Etk utilizes a phosphatidylinositol 3-kinase/Akt pathway to promote reporter activation driven by NF-kappaB, another oxygen-sensitive transcription factor, and to augment cytokine-induced inducible nitric oxide synthase expression in endothelial cells. To establish the clinical relevance of Etk-induced, hypoxia-mediated gene regulation, we examined Etk expression in keloid, which has elevated VEGF and PAI-1. We found that Etk is overexpressed in keloid (but not normal skin) tissues. The differential steady-state Etk protein levels were further confirmed in primary fibroblast cultures derived from these tissues, suggesting an Etk role in tissue fibrosis. Our results provide further understanding of Etk function within multiple signaling cascades to govern adaptive cytoprotection against extracellular stress in different cell systems, salivary epithelial cells, brain endothelial cells, and dermal fibroblasts.


Assuntos
Óxido Nítrico Sintase/biossíntese , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Northern Blotting , Western Blotting , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Hipóxia/metabolismo , Queloide/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Inibidor 1 de Ativador de Plasminogênio/genética , Proteínas Tirosina Quinases/efeitos dos fármacos , Interferência de RNA , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização/fisiologia
7.
Langmuir ; 20(23): 10168-73, 2004 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-15518509

RESUMO

Efforts have recently been made toward the study of interactions of phospholipid with various enzymes. It seems that phospholipids may be directly involved in regulating the enzyme activity. In this work, three phospholipid analogous polymers (PAPs), containing hydrophobic octyloxy, dodecyloxy, and octadecyloxy groups (abbreviated as 8-PAP, 12-PAP, and 18-PAP, respectively), were tethered on polypropylene hollow fiber microfiltration membrane (PPHFMM) to create a biocompatible interface for lipase immobilization. Lipase from Candida rugosa was immobilized on these PPHFMMs by adsorption. The adsorption capacity, activity, and thermal stability of enzyme on the PAP-modified PPHFMMs were compared with those of enzyme on the nascent ones. It was found that, as for the PAP-modified PPHFMMs, the adsorption capacities of lipase are lower than that of the nascent ones, while the activity retention of immobilized lipase increases from 57.5% to 74.1%, 77.5%, and 83.2% respectively for the 8-PAP-, 12-PAP-, and 18-PAP-modified PPHFMMs. In addition, the experimental results of thermal stability show that the residual activity of the immobilized lipase at 50 degrees C for 2 h is 62% for the 8-PAP-modified PPHFMM, 59% for the 12-PAP-modified PPHFMM, and 66% for the 18-PAP-modified PPHFMM, which are also higher than that of the nascent ones.


Assuntos
Lipase/química , Adsorção , Candida/enzimologia , Estabilidade Enzimática , Enzimas Imobilizadas , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Membranas Artificiais , Fosfolipídeos/química , Polipropilenos/química , Propriedades de Superfície , Temperatura
8.
Oncogene ; 21(57): 8817-29, 2002 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-12483534

RESUMO

Etk/Bmx, a member of the Tec family of non-receptor tyrosine kinase, is characterized by an N-terminal PH domain and has recently been shown to be involved in the regulation of various cellular processes, including proliferation, differentiation, motility and apoptosis. Since VEGF and the activation of its signaling pathway have been implicated in modulating a variety of biological responses, we characterized the role of Etk-dependent signaling pathways involved in the upregulation of VEGF expression, and explored the functional implications of this enhancement in sustaining cell proliferation and survival. Using Northern and Western analyses, transient transfections, and pharmacological agents, we demonstrate that Etk activation alone is sufficient to transcriptionally induce VEGF expression, independent of the previously identified hypoxia response element (HRE), in both Pa-4 epithelial and TR-BBB endothelial cells under normoxia. In addition, Etk utilizes both MEK/ERK and PI3-K/Pak1 signaling pathways in concert to activate VEGF transcription. Functionally, Etk activation elicits a profound stimulatory effect on TR-BBB cell proliferation and formation of capillary-like networks in Matrigel containing reduced levels of growth factors. Finally, antisense oligonucleotides against either endogenous VEGF or Etk abrogate the proliferation of Etk-activated TR-BBB cells, and exogenous VEGF treatment stimulates endogenous Etk tyrosine phosphorylation in HUVECs. Taken together, these results indicate that VEGF is both an Etk downstream target gene and an Etk upstream activator, constituting a reciprocal Etk-VEGF autoregulatory loop. These findings, to our knowledge, are the first delineation of a network of positive feedforward signaling pathways that converge on the Etk-VEGF axis, causally associating Etk-mediation of VEGF induction with enhanced cellular processes in both epithelial and endothelial cells.


Assuntos
Divisão Celular/genética , Sobrevivência Celular/genética , Fatores de Crescimento Endotelial/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfocinas/genética , Proteínas Tirosina Quinases/genética , Regulação para Cima , Animais , Linhagem Celular , Elementos Facilitadores Genéticos , Regiões Promotoras Genéticas , Ratos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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