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1.
Chem Biodivers ; : e202401027, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073310

RESUMO

Four new prenylated acetophenone derivatives, including one acetophenone dimer [acronyrone D (1)] and three acetophenone monomers [acronyrones E-G (2-4)], along with seven known analogues (5-11) were obtained from the leaves of Acronychia pedunculata. Their structures and absolute configurations were established by analysis of HRMS and NMR data, single crystal X-ray diffraction studies and quantum chemical calculations. In addition, the isolates were tested for their anti-proliferative acivity against HCT-116, RKO and SW480 cancer cell lines. Remarkably, compound 5 exhibited significant anti-proliferative effects on the three cell lines, with IC50 values ranging from 0.24 to 5.3 µM.

2.
Front Med (Lausanne) ; 10: 1143978, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521338

RESUMO

Objective: To compare the diagnostic value of cytobrush, ERCP-guided biopsy, SpyGlass direct visual impression and SpyGlass-guided biospy (SpyBite) in the differential diagnosis of benign and malignant bile duct strictures. Methods: The data of 1,008 patients who were clinically diagnosed with indeterminate biliary strictures and underwent ERCP-guided biopsy, cytobrush, SpyGlass direct visual impression or SpyBite at the First Affiliated Hospital of Nanchang University between January 2010 and December 2019 were collected and analyzed retrospectively. The final diagnose was determined by surgical pathological specimen or follow-up (Malignant stricture can be identified if the stricture showed malignant progression during one year of follow-up). The differential diagnostic value of the above endoscopic diagnostic methods was evaluated by means of sensitivity, specificity, accuracy, positive predictive value, negative predictive value, etc. and safety was evaluated by the incidence rate of adverse events. Results: In terms of sensitivity, standard biopsy group (48.6%) and SpyBite group (61.5%) were significantly higher than cytobrush group (32.0%), and visual impression group (100%) was significantly higher than any other group. As far as specificity was concerned, cytobrush group (99.0%), standard biopsy group (99.3%) and the SpyBite group (100%) were significantly higher than visual impression (55.6%), but there was no statistical difference among the three groups above. As far as accuracy was concerned, standard biopsy group (65.3%), and SpyBite group (80.0%) were significantly higher than cytobrush group (44.4%), and SpyBite group (80.0%) was significantly higher than visual impression group (54.8%). In terms of safety, visual impression group and SpyBite group were significantly higher than cytobrush group and standard biopsy group in post-ERCP cholangitis. Conclusion: SpyBite combined with SpyGlass-guided visual impression was better for differential diagnosis of benign and malignant bile duct strictures in terms of sensitivity and accuracy compared with conventional endoscopic diagnostic methods such as cytobrush and standard biopsy. Furthmore, the incidence rates of adverse events after SpyGlass examination was similar to those after conventional endoscopic diagnostic methods except for higher cholangitis, which could be controlled by antibiotics and might be avoided by adequate biliary drainage.

3.
Proc Natl Acad Sci U S A ; 117(36): 22390-22401, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848063

RESUMO

Targeted cancer therapy aims to achieve specific elimination of cancerous but not normal cells. Recently, PIWI proteins, a subfamily of the PAZ-PIWI domain (PPD) protein family, have emerged as promising candidates for targeted cancer therapy. PPD proteins are essential for small noncoding RNA pathways. The Argonaute subfamily partners with microRNA and small interfering RNA, whereas the PIWI subfamily partners with PIWI-interacting RNA (piRNA). Both PIWI proteins and piRNA are mostly expressed in the germline and best known for their function in transposon silencing, with no detectable function in mammalian somatic tissues. However, PIWI proteins become aberrantly expressed in multiple types of somatic cancers, thus gaining interest in targeted therapy. Despite this, little is known about the regulatory mechanism of PIWI proteins in cancer. Here we report that one of the four PIWI proteins in humans, PIWIL1, is highly expressed in gastric cancer tissues and cell lines. Knocking out the PIWIL1 gene (PIWIL1-KO) drastically reduces gastric cancer cell proliferation, migration, metastasis, and tumorigenesis. RNA deep sequencing of gastric cancer cell line SNU-1 reveals that KO significantly changes the transcriptome, causing the up-regulation of most of its associated transcripts. Surprisingly, few bona fide piRNAs exist in gastric cancer cells. Furthermore, abolishing the piRNA-binding activity of PIWIL1 does not affect its oncogenic function. Thus, PIWIL1 function in gastric cancer cells is independent of piRNA. This piRNA-independent regulation involves interaction with the UPF1-mediated nonsense-mediated mRNA decay (NMD) mechanism. Altogether, our findings reveal a piRNA-independent function of PIWIL1 in promoting gastric cancer.


Assuntos
Proteínas Argonautas , RNA Interferente Pequeno , Neoplasias Gástricas , Animais , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Linhagem Celular Tumoral , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Camundongos Nus , Degradação do RNAm Mediada por Códon sem Sentido/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Estômago/química , Estômago/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
4.
Neuroreport ; 31(1): 1-8, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31688420

RESUMO

Hyperactivity of the hypothalamic-pituitary-adrenal axis and impairment of the central corticotropin-releasing factor system are factors in the pathogenesis of depression. Though several antagonists of the corticotropin-releasing factor 1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between corticotropin-releasing factor 1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of CP154526, a corticotropin-releasing factor 1 receptor blocker, which presented some signs of depression. Our results revealed that CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment notably improved the sucrose consumption, produced anti-depressive-like behavior in open-field test, as well as immobility time in forced swimming test. The levels of interleukin-6, interleukin-1ß, tumor necrosis factor-α, and corticotropin-releasing hormone concentration in the serum were inhibited effectively by CP154526 or fluoxetine administration. Real-time quantitative PCR and western blot analysis showed the upregulated levels of brain-derived neurotrophic factor and growth associated protein 43 (GAP43) in the hypothalamus of the rats exposed to chronic unpredictable mild stress (CUMS), while different degrees of downregulation in their expression were detected after CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment, respectively. Thus, our data demonstrated that CP154526 exhibited antidepressant effect in CUMS rats, which might be mediated by decreasing the brain-derived neurotrophic factor and GAP43 expression in the hypothalamus.


Assuntos
Antidepressivos/farmacologia , Depressão/etiologia , Depressão/metabolismo , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Estresse Psicológico/complicações , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína GAP-43/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
5.
Seizure ; 71: 322-327, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31525612

RESUMO

PURPOSE: Tuberous sclerosis complex (TSC) is characterized by the development of hamartomas in multiple organ systems. This study attempted to screen mutations and to investigate the mutation distribution and related phenotypes including epilepsy of Chinese TSC patients. METHODS: We performed the genotypic analysis of TSC1 and TSC2 genes in 77 unrelated Chinese TSC patients using direct Sanger sequencing and Multiplex ligation-dependent probe amplification (MLPA). RESULTS: Mutations were identified in a total of 63 (81.8%) cases, including 18 TSC1 mutations (8 nonsense mutations, 6 frameshift, 1 in-frame shift, 1 missense and 2 splice-site) and 45 TSC2 mutations (13 missense, 3 nonsense, 6 splicing, 6 in-frame shift,12 frameshift mutations and 5 large deletions). Large deletions were presented exclusively in TSC2 gene, accounting for 7.9% of all mutations in this study. Fourteen novel mutations were identified in this study. CONCLUSIONS: Epilepsy occurs in approximately 75.3% (58/77) of patients. Hypomelanotic macules occurred significantly more often in patients with TSC2 mutations and cases with TSC1/TSC2 mutations had a significantly higher frequency of cortical nodule than patients with no mutations identified. Overall, our data expands the spectrum of mutations associated with the TSC loci and will be of value to the genetic counseling in patients with the disease.


Assuntos
Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Esclerose Tuberosa/genética , Esclerose Tuberosa/patologia , Esclerose Tuberosa/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Epilepsia/epidemiologia , Epilepsia/genética , Epilepsia/patologia , Epilepsia/fisiopatologia , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Mutação , Fenótipo , Análise de Sequência de DNA , Esclerose Tuberosa/epidemiologia , Adulto Jovem
6.
J Biol Chem ; 294(25): 9873-9887, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31076507

RESUMO

PIWI proteins are key regulators of germline and somatic stem cells throughout different evolutionary lineages. However, how PIWI proteins themselves are regulated remains largely unknown. To identify candidate proteins that interact with PIWI proteins and regulate their stability, here we established a yeast two-hybrid (Y2H) assay in the planarian species Schmidtea mediterranea We show that DNAJA1, a heat shock protein 40 family member, interacts with the PIWI protein SMEDWI-2, as validated by the Y2H screen and co-immunoprecipitation assays. We found that DNAJA1 is enriched in planarian adult stem cells, the nervous system, and intestinal tissues. DNAJA1-knockdown abolished planarian regeneration and homeostasis, compromised stem cell maintenance and PIWI-interacting RNA (piRNA) biogenesis, and deregulated SMEDWI-1/2 target genes. Mechanistically, we observed that DNAJA1 is required for the stability of SMEDWI-1 and SMEDWI-2 proteins. Furthermore, we noted that human DNAJA1 binds to Piwi-like RNA-mediated gene silencing 1 (PIWIL1) and is required for PIWIL1 stability in human gastric cancer cells. In summary, our results reveal not only an evolutionarily conserved functional link between PIWI and DNAJA1 that is essential for PIWI protein stability and piRNA biogenesis, but also an important role of DNAJA1 in the control of proteins involved in stem cell regulation.


Assuntos
Proteínas Argonautas/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Helminto/metabolismo , Homeostase , Planárias/fisiologia , Regeneração , Células-Tronco/citologia , Animais , Proteínas Argonautas/química , Proteínas Argonautas/genética , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células HEK293 , Proteínas de Choque Térmico HSP40/química , Proteínas de Choque Térmico HSP40/genética , Proteínas de Helminto/química , Proteínas de Helminto/genética , Humanos , Planárias/embriologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Células-Tronco/metabolismo , Técnicas do Sistema de Duplo-Híbrido
7.
Oncotarget ; 8(26): 42495-42509, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28477008

RESUMO

Glioblastoma multiforme (GBM) is the most common and deadly brain cancer, characterized by its aggressive proliferation to adjacent tissue and high recurrence rate. We studied the efficacy and related mechanisms of the combination of cyclopamine (Cyp, a Sonic-hedgehog pathway (Shh) inhibitor) and temozolomide (TMZ, the clinically most used chemotherapeutic agent) in anti-GBM treatment. The micellarized Cyp (MCyp) showed better performance than Cyp solution in inhibiting GBM cells proliferation (3.77-fold against U87 MG cells and 3.28-fold against DBTRG-05MG cells) and clonogenity (1.35-fold against U87 MG cells and 2.17-fold against DBTRG-05MG cells), and preferred behavior of inhibiting cell invasion, colony formation through attenuated Gli1 expression. In addition, combination of MCyp and TMZ exhibited synergistic cytotoxicity, correlating with their ability in inducing apoptosis and eliminating neurospheres formation, and the combination of TMZ was accompanied with the enhanced blockage of Shh pathway. The optimal ratio of MCyp combined to TMZ was 1:20. So we proposed to use TMZ to kill tumor parenchyma and MCyp as the cancer stem cells inhibitor to resist tumor recurrence. These findings demonstrated that combination of TMZ with micellarized Cyp is a promising strategy for exerting different functions of drugs for tumor treatment.


Assuntos
Neoplasias Encefálicas/metabolismo , Dacarbazina/análogos & derivados , Glioblastoma/metabolismo , Micelas , Alcaloides de Veratrum/administração & dosagem , Proteína GLI1 em Dedos de Zinco/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/administração & dosagem , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Temozolomida , Ensaio Tumoral de Célula-Tronco , Proteína GLI1 em Dedos de Zinco/genética
8.
Mol Pharm ; 14(4): 1012-1022, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28252970

RESUMO

For aggressive brain glioblastoma, the therapy is significantly impaired by blood-brain barrier (BBB) and blood-tumor barrier (BTB). Choosing more than one target from the pool of tumor-stroma interactions is profoundly beneficial to therapeutic approaches. Thus, a multifunctional liposomal system based on anchoring two receptor-specific and penetrable peptides was designed for the combination delivery of BBB-impermeable siRNA and chemotherapeutic docetaxel to brain glioblastoma. Both macroscopic and microscopic specific distributions and targeting effect of the liposomes in the intracranial glioblastoma were confirmed. Superiority in therapeutic efficacies of the siRNA and DTX combination delivery system was revealed from encouraged VEGF gene silencing, tumor cell apoptosis, prolonged survival time, subdued glioblastoma cells in intracranial glioblastoma, and negligible system toxicities after systemic application. Furthermore, the liposomes made better modulation of glioblastoma microenvironment such as the down-regulation of CD31-positive tumor vessels and HIF-1α expression. The transport mechanism of the liposomes delivering the cargos across BBB via receptor-mediated transcytosis without destroying the integrity of BBB has been evaluated from in vitro and in vivo. Therefore, the dual peptides-modified liposomal system provides a safe and noninvasive approach for the delivery of siRNA and chemotherapeutic molecules across the BBB and BTB to target therapy of brain glioblastoma.


Assuntos
Antineoplásicos/administração & dosagem , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , RNA Interferente Pequeno/administração & dosagem , Microambiente Tumoral/fisiologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Docetaxel , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lipossomos/administração & dosagem , Camundongos , Peptídeos/metabolismo , Taxoides/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Bioorg Med Chem Lett ; 26(19): 4580-4586, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27597251

RESUMO

A series of [1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine derivatives have been synthesized and their structures were confirmed by single-crystal X-ray diffraction. Compared to some reported structures of 1,6-dihydro-1,2,4,5-tetrazine, these compounds can't be considered as having homoaromaticity. Their antiproliferative activities were evaluated against MCF-7, Bewo and HL-60 cells in vitro. Two compounds were highly effective against MCF-7, Bewo and HL-60 cells with IC50 values in 0.63-13.12µM. Three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were carried out on 51 [1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine derivatives with antiproliferative activity against MCF-7 cell. Models with good predictive abilities were generated with the cross validated q(2) values for CoMFA and CoMSIA being 0.716 and 0.723, respectively. Conventional r(2) values were 0.985 and 0.976, respectively. The results provide the tool for guiding the design and synthesis of novel and more potent tetrazine derivatives.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Triazóis/síntese química , Triazóis/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Relação Quantitativa Estrutura-Atividade , Triazóis/química
10.
Bioorg Med Chem Lett ; 26(13): 3042-3047, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27184766

RESUMO

A series of [1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine derivatives have been synthesized and evaluated for their antitumor activities. These compounds exhibited potent antiproliferative activities against MCF-7, Bewo and HL-60 cells and c-Met kinase inhibitory activities. Three compounds were highly effective against MCF-7, Bewo and HL-60 cells with IC50 values in 1.09-2.24µM. Molecular docking was further performed to study the inhibitor-c-Met kinase interactions, and the results show that compound 4j was potently bound to the c-Met kinase with three hydrogen bonds. The further research on acute toxicity and in vivo antitumor activity of compound 4j to ICR (Institute of Cancer Research) mice were carried out, and found 4j with a certain toxicity but good efficacy in vivo. Based on the preliminary results, it is deduced that compound 4j with potent c-Met kinase inhibitory activity may be a potential anticancer agent.


Assuntos
Antineoplásicos/farmacologia , Compostos Heterocíclicos com 2 Anéis/farmacologia , Triazóis/farmacologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Sítios de Ligação , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Compostos Heterocíclicos com 2 Anéis/administração & dosagem , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/toxicidade , Humanos , Concentração Inibidora 50 , Células MCF-7 , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Estaurosporina/farmacologia , Relação Estrutura-Atividade , Triazóis/administração & dosagem , Triazóis/síntese química , Triazóis/toxicidade
11.
Mol Pharm ; 12(6): 2189-202, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25945733

RESUMO

Multidrug resistance (MDR) presents a clinical obstacle to cancer chemotherapy. The main purpose of this study was to evaluate the potential of a hyaluronic acid (HA) and α-tocopheryl succinate (α-TOS) based nanoparticle to enhance cancer cell recognition and overcome MDR, and to explore the underlying mechanisms. A multifunctional nanoparticle, HTTP-50 NP, consisted of HA-α-TOS (HT) conjugate and d-α-tocopheryl polyethylene glycol succinate (TPGS) with docetaxel loaded in its hydrophobic core. The promoted tumor cell recognition and accumulation, cytotoxicity, and mitochondria-specific apoptotic pathways for the HTTP-50 NP were confirmed in MCF-7/Adr cells (P-gp-overexpressing cancer model), indicating that the formulated DTX and the conjugated α-TOS in the HTTP-50 NP could synergistically circumvent the acquired and intrinsic MDR in MCF-7/Adr cells. In vivo investigation on the MCF-7/Adr xenografted nude mice models confirmed that HTTP-50 NP possessed much higher tumor tissue accumulation and exhibited pronouncedly enhanced antiresistance tumor efficacy with reduced systemic toxicity compared with HTTP-0 NP and Taxotere. The mechanisms of the multifunctional HTTP-50 NP to overcome MDR and enhance antiresistance efficacy may be contributed by CD44 receptor-targeted delivery and P-gp efflux inhibition, and meanwhile to maximize antitumor efficacy by synergism of DTX and mitocan of α-TOS killing tumor cells.


Assuntos
Ácido Hialurônico/química , Nanopartículas/química , alfa-Tocoferol/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Docetaxel , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Taxoides/química , Taxoides/farmacologia , Difração de Raios X
12.
Biomaterials ; 35(19): 5226-39, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24695093

RESUMO

Combinations of drugs promoting anti-angiogenesis and apoptosis effects are meaningful for cancer therapy. In the present study, dual peptides-modified liposomes were designed by attaching two receptor-specific peptides, specifically low-density lipoprotein receptor-related protein receptor (Angiopep-2) and neuropilin-1 receptor (tLyP-1) for brain tumor targeting and tumor penetration. Vascular endothelial growth factor (VEGF) siRNA and chemotherapeutic docetaxel (DTX) were chosen as the two payloads because VEGF is closely associated with angiogenesis, and DTX can kill tumor cells efficiently. Binding to glioma cells, co-delivery of siRNA and DTX in human glioblastoma cells (U87 MG) and murine brain microvascular endothelial cells (BMVEC), VEGF gene silencing, antiproliferation and anti-tumor effects of the dual peptides-modified liposomes were evaluated in vitro and in vivo. The dual peptides-modified liposomes persisted the binding ability to glioma cells, enhanced the internalization via specific receptor mediated endocytosis and tissue penetration, thus the dual peptides-modified liposomes loading VEGF siRNA and DTX possessed stimulative gene silencing and antiproliferation activity compared with non-modified and single peptide-modified liposomes. The co-delivery research revealed different intracellular behavior of hydrophilic large molecular and lipophilic small molecule, the former involves endocytosis and subsequent escape of endosome/lysosomes, while the latter experiences passive diffusion of lipophilic small drugs after its release. Furthermore, the dual peptides-modified liposomes showed superiority in anti-tumor efficacy, combination of anti-angiogenesis by VEGF siRNA and apoptosis effects by DTX, after both intratumor and system application against mice with U87 MG tumors, and the treatment did not activate system-associated toxicity or the innate immune response. Combination with the dual peptides-guided tumor homing and penetration, the dual peptides-modified liposomes provide a strategy for effective targeting delivery of siRNA and DTX into the glioma cell and inhibition of tumor growth in a synergistic manner.


Assuntos
Glioma/tratamento farmacológico , Lipossomos/química , Peptídeos/química , RNA Interferente Pequeno/administração & dosagem , Taxoides/administração & dosagem , Taxoides/uso terapêutico , Animais , Linhagem Celular Tumoral , Docetaxel , Humanos , Masculino , Camundongos , Camundongos Nus
13.
World J Gastroenterol ; 19(37): 6310-4, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24115833

RESUMO

Biliary cystadenoma (BCA) is a rare hepatic neoplasm. Although considered a benign cystic tumor of the liver, BCA has a high risk of recurrence with incomplete excision and a potential risk for malignant degeneration. Correct diagnosis and complete tumor excision with negative margins are the mainstay of treatment. Unfortunately, due to the lack of presenting symptoms, and normal laboratory results in most patients, BCA is hard to distinguish from other cystic lesions of the liver such as biliary cystadenocarcinoma, hepatic cyst, hydatid cyst, Caroli disease, undifferentiated sarcoma, intraductal papillary mucinous tumor, and hepatocellular carcinoma. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) may be necessary. They demonstrate intrahepatic cystic lesions with features such as mural nodules, varying wall thickness, papillary projections, and internal septations. Nevertheless, surgery is still the only means of accurate diagnosis. Definitive diagnosis requires histological examination following formal resection. We describe a 57-year-old woman initially diagnosed with polycystic liver who was subsequently diagnosed with giant intrahepatic BCA in the left hepatic lobe. This indicates that both US physicians and hepatobiliary specialists should attach importance to hepatic cysts, and CT or MRI should be performed for further examination when a diagnosis of BCA is suspected.


Assuntos
Cistadenoma/diagnóstico , Cistos/diagnóstico , Hepatopatias/diagnóstico , Neoplasias Hepáticas/diagnóstico , Biópsia , Colecistectomia , Cistadenoma/complicações , Cistadenoma/cirurgia , Cistos/complicações , Cistos/cirurgia , Erros de Diagnóstico/prevenção & controle , Feminino , Hepatectomia , Humanos , Hepatopatias/complicações , Hepatopatias/cirurgia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X
14.
Biomaterials ; 34(28): 6976-91, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23777916

RESUMO

In the hormone-refractory stage of prostate cancer (PC), the expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) often remains highly active. Accumulating studies have demonstrated that these two proteins are attractive targets for specific delivery of functional molecules to advanced PC, not merely as potential sensitive markers for PC detection. In this study, we constructed a dual-modified liposome that incorporated PSA-responsive and PSMA-mediated liposomes and potentially offers double selectivity for PC. The folate moiety binds quickly to PSMA-positive tumors, and the PSA-responsive moiety is cleaved by PSA that was enriched in tumor tissues. The activated liposomes (folate and cell-penetrating peptides dual-modifications) are subsequently taken up by the tumor cells via polyarginine's penetrating effects and receptor-mediated endocytosis. To corroborate these assumptions, a series of experiments were conducted, including PSA-responsive peptide hydrolysis kinetics, cellular uptake, internalization mechanism and escape from endosomes in PC-3 and/or 22Rv1 cells, biodistribution and antitumor activity of siRNA-loaded liposomes after systemic administration, gene silencing and cell apoptosis in vitro and in vivo. The results reveal that multivalent interactions play a key role in enhancing PC cell recognition and uptake while reducing nonspecific uptake. The dual-modified liposomes carrying small interfering RNA (siRNA) have significant advantages over the control liposomes, including single-modified (folate, CPP, PSA-responsive only) and non-modified liposomes. The dual-modified liposomes elevated cellular uptake, downregulated expression of polo-like kinase 1 (PLK-1) and augmented cell apoptosis in prostate tumor cells. The entry of the dual-modified liposomes into 22Rv1 cells occurred via multiple endocytic pathways, including clathrin-mediated endocytosis and macropinocytosis, followed by an effective endosomal escape of the entrapped siRNA into the cytoplasm. In vivo studies conducted on a 22Rv1 xenograft murine model demonstrated that the dual-modified liposomes demonstrated the maximized accumulation, retention and knockdown of PLK-1 in tumor cells, as well as the strongest inhibition of tumor growth and induction of tumor cell apoptosis. In terms of targeting capacity and therapeutic potency, the combination of a PSA-responsive and PSMA-mediated liposome presents a promising platform for therapy and diagnosis of PSMA/PSA-positive PC.


Assuntos
Antígenos de Superfície/química , Glutamato Carboxipeptidase II/química , Lipossomos/química , Antígeno Prostático Específico/química , Neoplasias da Próstata/terapia , RNA Interferente Pequeno/genética , Animais , Apoptose , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Quinase 1 Polo-Like
15.
Biomaterials ; 34(20): 4849-59, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23541420

RESUMO

A nanocarrier delivery system that can simultaneously deliver a chemotherapeutic drug and siRNA to the tumor is emerging as a promising treatment strategy for cancer treatment. In this study, a multifunctional PHD/PPF/siRNA complexes was developed by one-step assembly of prefunctionalized polymers: PEI-HZ-DOX (PHD) and PEI-PEG-Folate (PPF) with siRNA. The PHD, a conjugate of PEI (polyethylenimine) with doxorubicin (DOX) via a pH-responsive hydrazone linkage, enables pH-controlled drug release. The PPF, a tumor-targeting folate ligand conjugated to PEI using polyethyleneglycol (PEG) as a linker, enables immune evasion and cell-specific targeting. The prefunctionalized PHD and PPF as well as the self-assembly complexes reveals advantage on safety in further application for siRNA delivery. By exploiting distinct triple ratios of PHD, PPF and siRNA during nanocomplexes formulation, the folate surface density, DOX loading amount and siRNA complexation can be precisely and reproducibly changed. The studies showed that the complexes was capable of delivering siRNA and DOX to cancerous cells and release synchronously in cell by acid-triggered manner, i.e. hydrazone bond cleavage and endosome/lysosome escape using flow cytometry and confocal laser scanning microscopy analysis. The results highlight the potential for therapeutic gene silencing in vitro and in vivo using RT-PCR and non-invasive in vivo imaging systems. The PHD/PPF/siRNA complexes can increase DOX and siRNA accumulation in cancerous cells and decrease the nonspecific distribution in normal tissues by the combination of EPR effect of nanocarriers, pH-triggered drug release, folate-mediated targeted delivery, and synergistic action of DOX and siRNA.


Assuntos
Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Ácido Fólico/análogos & derivados , Técnicas de Transferência de Genes , Neoplasias/tratamento farmacológico , Polietilenoglicóis/química , Polietilenoimina/química , RNA Interferente Pequeno/administração & dosagem , Animais , Doxorrubicina/farmacologia , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Feminino , Ácido Fólico/síntese química , Ácido Fólico/química , Inativação Gênica/efeitos dos fármacos , Células HeLa , Humanos , Hidrazonas/química , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Polietilenoglicóis/síntese química , Polietilenoimina/síntese química , RNA Interferente Pequeno/metabolismo , Distribuição Tecidual/efeitos dos fármacos
16.
Chem Commun (Camb) ; 48(14): 2024-6, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22234426

RESUMO

An iron(III)-catalyzed three-component coupling reaction of alkynes, CH(2)Cl(2) and amines was developed for facile synthesis of propargylamines. Preliminary mechanism investigation using in situ FT-IR reveals that the crucial Fe-acetylide intermediate could be formed through C-H bond activation of alkynes thanks to cooperative effect of FeCl(3) and 1,1,3,3-tetramethylguanidine.


Assuntos
Alcinos/química , Aminas/química , Compostos Férricos/química , Cloreto de Metileno/química , Pargilina/análogos & derivados , Propilaminas/química , Catálise , Pargilina/química , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Cell Biol Toxicol ; 28(1): 47-56, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22012578

RESUMO

The pseudo-tumoral expansion of fibroblast-like synoviocytes is a hallmark of rheumatoid arthritis (RA), and targeting rheumatoid arthritis fibroblast-like synoviocytes (RAFLSs) may have therapeutic potentials in this disease. Andrographolide, a diterpenoid compound isolated from the herb Andrographis paniculata, has been reported to have potent anti-inflammatory activity. In the present study, we aimed to investigate the effects of andrographolide on human RAFLSs and the underlying molecular mechanism(s). RAFLSs were isolated from patients with RA and treated with or without various concentrations (i.e., 10, 20, and 30 µM) of andrographolide for 48 h. 3-[4,5-Dimethyl-2-yl]-2,5-diphenyl tetrazolium bromide assay revealed that andrographolide treatment decreased the proliferation of RAFLSs in a dose-dependent manner. Cell cycle analysis using propidium iodide (PI) staining showed a G0/G1 cell cycle arrest in andrographolide-treated RAFLSs. Immunoblotting analysis of key cell cycle regulators demonstrated that andrographolide treatment caused a dose-dependent increase in the expression of cell-cycle inhibitors p21 and p27 and a concomitant reduction of cyclin-dependent kinase 4. Exposure to andrographolide-induced apoptosis of RAFLSs measured by annexin V/PI double staining, which was coupled with promotion of cytochrome C release from mitochondria and activation of caspase-3. Moreover, andrographolide-treated RAFLSs displayed a significant decrease in the Bcl-2/Bax ratio compared to untreated cells. In conclusion, our data demonstrate that andrographolide exerts anti-growth and pro-apoptotic effects on RAFLSs, thus may have therapeutic potential for the treatment of RA.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular , Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Líquido Sinovial/citologia , Anti-Inflamatórios/farmacologia , Artrite Reumatoide/metabolismo , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quinase 4 Dependente de Ciclina/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Citocromos c/efeitos dos fármacos , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Líquido Sinovial/efeitos dos fármacos , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
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