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1.
J Clin Ultrasound ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769712

RESUMO

Left ventricular-right atrial communication (LV-RAC) refers to the shunt from the left ventricle to the right atrium caused by an abnormal channel between the left ventricle and the right atrium, and is a specific type of ventricular septal defect that is rare. We diagnosed one case using echocardiography.

2.
Hepatology ; 75(1): 182-195, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34396571

RESUMO

BACKGROUND AND AIM: HBV DNA can be reduced using antiviral drugs in patients with chronic hepatitis B (CHB); however, the rate of HBeAg seroconversion remains low. A clinical trial was conducted to assess the efficacy and safety of a de novo designed liposome-based nanoparticle lipopeptide vaccine, εPA-44, for CHB. APPROACH AND RESULTS: A two-stage phase 2 trial, which included a 76-week, randomized, double-blind, placebo-controlled trial (stage 1) and a 68-week open-label extension (stage 2), was conducted in 15 centers across China (Clinicaltrials.gov No. NCT00869778). In stage 1, 360 human leukocyte antigen A2 (HLA-A2)-positive and HBeAg-positive patients were randomly and equally distributed to receive six subcutaneous injections of 600 µg or 900 µg εPA-44 or placebo at week 0, 4, 8, 12, 20, and 28. In stage 2, 183 patients received extended 900 µg εPA-44, and 26 patients were observed for relapse without further treatment. The primary endpoint was the percentage of patients with HBeAg seroconversion at week 76. At week 76, patients receiving 900 µg εPA-44 achieved significantly higher HBeAg seroconversion rate (38.8%) versus placebo (20.2%) (95% CI, 6.9-29.6%; p = 0.002). With a combined endpoint of HBeAg seroconversion, alanine aminotransferase normalization and HBV DNA < 2,000 IU/mL, both 900 µg (18.1%) and 600 µg (14.3%), resulted in significantly higher rate versus placebo (5.0%) (p = 0.002 and p = 0.02, respectively) at week 76. In stage 2, none (0 of 20) of 900 µg εPA-44-treated patients experienced serologic relapse. The safety profile of εPA-44 was comparable to that of placebo. CONCLUSIONS: Among HLA-A2-positive patients with progressive CHB, a finite duration of 900 µg εPA-44 monotherapy resulted in significantly higher HBeAg seroconversion rate than placebo and sustained off-treatment effect. A phase 3 trial is ongoing (ChiCTR2100043708).


Assuntos
Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/terapia , Vacinas contra Hepatite Viral/administração & dosagem , Adolescente , Adulto , Método Duplo-Cego , Feminino , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Injeções Subcutâneas , Lipossomos , Masculino , Sistemas de Liberação de Fármacos por Nanopartículas , Soroconversão , Resposta Viral Sustentada , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Vacinas de Subunidades Antigênicas/química , Vacinas contra Hepatite Viral/efeitos adversos , Vacinas contra Hepatite Viral/química , Adulto Jovem
3.
Cell Biol Toxicol ; 39(6): 2501-2526, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37755585

RESUMO

Nasopharyngeal carcinoma (NPC) is a distinct type of head and neck cancer that is highly associated with Epstein-Barr virus (EBV) infection. EBV acts as an epigenetic driver in NPC tumorigenesis, reprogramming the viral and host epigenomes to regulate viral latent gene expression, and creating an environment conducive to the malignant transformation of nasopharyngeal epithelial cells. Targeting epigenetic mechanisms in pre-clinical studies has been shown promise in eradicating tumours and overcoming immune resistance in some solid tumours. However, its efficacy in NPC remains inclusive due to the complex nature of this cancer. In this review, we provide an updated understanding of the roles of epigenetic factors in regulating EBV latent gene expression and promoting NPC progression. We also explore the crosstalk between epigenetic mechanisms and immune evasion in NPC. Particularly, we discuss the potential roles of DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitors in reversing immune suppression and augmenting antitumour immunity. Furthermore, we highlight the advantages of combining epigenetic therapy and immune checkpoint inhibitor to reverse immune resistance and improve clinical outcomes. Epigenetic drugs have the potential to modulate both epigenetic mediators and immune factors involved in NPC. However, further research is needed to fully comprehend the diverse range of epigenetic modifications in NPC. A deeper understanding of the crosstalk between epigenetic mechanisms and immune evasion during NPC progression is crucial for the development of more effective treatments for this challenging disease.


Assuntos
Carcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patologia , Evasão da Resposta Imune , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Epigênese Genética
4.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834058

RESUMO

Puberty is a critical developmental period of life characterized by marked physiological changes, including changes in the immune system and gut microbiota development. Exposure to inflammation induced by immune stressors during puberty has been found to stimulate central inflammation and lead to immune disturbance at distant sites from the gut; however, its enduring effects on gut immunity are not well explored. Therefore, in this study, we used a pubertal lipopolysaccharides (LPS)-induced inflammation mouse model to mimic pubertal exposure to inflammation and dysbiosis. We hypothesized that pubertal LPS-induced inflammation may cause long-term dysfunction in gut immunity by enduring dysregulation of inflammatory signaling and epigenetic changes, while prebiotic/probiotic intake may mitigate the gut immune system deregulation later in life. To this end, four-week-old female Balb/c mice were fed prebiotics/probiotics and exposed to LPS in the pubertal window. To better decipher the acute and enduring immunoprotective effects of biotic intake, we addressed the effect of treatment on interleukin (IL)-17 signaling related-cytokines and pathways. In addition, the effect of treatment on gut microbiota and epigenetic alterations, including changes in microRNA (miRNA) expression and DNA methylation, were studied. Our results revealed a significant dysregulation in selected cytokines, proteins, and miRNAs involved in key signaling pathways related to IL-17 production and function, including IL-17A and F, IL-6, IL-1ß, transforming growth factor-ß (TGF-ß), signal transducer and activator of transcription-3 (STAT3), p-STAT3, forkhead box O1 (FOXO1), and miR-145 in the small intestine of adult mice challenged with LPS during puberty. In contrast, dietary interventions mitigated the lasting adverse effects of LPS on gut immune function, partly through epigenetic mechanisms. A DNA methylation analysis demonstrated that enduring changes in gut immunity in adult mice might be linked to differentially methylated genes, including Lpb, Rorc, Runx1, Il17ra, Rac1, Ccl5, and Il10, involved in Th17 cell differentiation and IL-17 production and signaling. In addition, prebiotic administration prevented LPS-induced changes in the gut microbiota in pubertal mice. Together, these results indicate that following a healthy diet rich in prebiotics and probiotics is an optimal strategy for programming immune system function in the critical developmental windows of life and controlling inflammation later in life.


Assuntos
Interleucina-17 , Cogumelos Shiitake , Camundongos , Animais , Feminino , Interleucina-17/metabolismo , Cogumelos Shiitake/metabolismo , Lipopolissacarídeos/toxicidade , Maturidade Sexual , Prebióticos , Transdução de Sinais , Citocinas/metabolismo , Inflamação , Epigênese Genética
5.
Int J Mol Sci ; 23(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35163030

RESUMO

c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) family members integrate signals that affect proliferation, differentiation, survival, and migration in a cell context- and cell type-specific way. JNK and p38 MAPK activities are found upregulated in nasopharyngeal carcinoma (NPC). Studies have shown that activation of JNK and p38 MAPK signaling can promote NPC oncogenesis by mechanisms within the cancer cells and interactions with the tumor microenvironment. They regulate multiple transcription activities and contribute to tumor-promoting processes, ranging from cell proliferation to apoptosis, inflammation, metastasis, and angiogenesis. Current literature suggests that JNK and p38 MAPK activation may exert pro-tumorigenic functions in NPC, though the underlying mechanisms are not well documented and have yet to be fully explored. Here, we aim to provide a narrative review of JNK and p38 MAPK pathways in human cancers with a primary focus on NPC. We also discuss the potential therapeutic agents that could be used to target JNK and p38 MAPK signaling in NPC, along with perspectives for future works. We aim to inspire future studies further delineating JNK and p38 MAPK signaling in NPC oncogenesis which might offer important insights for better strategies in diagnosis, prognosis, and treatment decision-making in NPC patients.


Assuntos
Antineoplásicos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Humanos , Carcinoma Nasofaríngeo/enzimologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/patologia
6.
J Cell Mol Med ; 25(17): 8187-8200, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34322995

RESUMO

Prostate cancer (PCa) is the second most common malignancy and is the fifth leading cause of cancer mortality among men globally. Docetaxel-based therapy remains the first-line treatment for metastatic castration-resistant prostate cancer. However, dose-limiting toxicity including neutropenia, myelosuppression and neurotoxicity is the major reason for docetaxel dose reductions and fewer cycles administered, despite a recent study showing a clear survival benefit with increased total number of docetaxel cycles in PCa patients. Although previous studies have attempted to improve the efficacy and reduce docetaxel toxicity through drug combination, no drug has yet demonstrated improved overall survival in clinical trial, highlighting the challenges of improving the activity of docetaxel monotherapy in PCa. Herein, we identified 15 lethality hits for which inhibition could enhance docetaxel sensitivity in PCa cells via a high-throughput kinome-wide loss-of-function screen. Further drug-gene interactions analyses identified Janus kinase 1 (JAK1) as a viable druggable target with existing experimental inhibitors and FDA-approved drugs. We demonstrated that depletion of endogenous JAK1 enhanced docetaxel-induced apoptosis in PCa cells. Furthermore, inhibition of JAK1/2 by baricitinib and ruxolitinib synergizes docetaxel sensitivity in both androgen receptor (AR)-negative DU145 and PC3 cells, but not in the AR-positive LNCaP cells. In contrast, no synergistic effects were observed in cells treated with JAK2-specific inhibitor, fedratinib, suggesting that the synergistic effects are mainly mediated through JAK1 inhibition. In conclusion, the combination therapy with JAK1 inhibitors and docetaxel could be a useful therapeutic strategy in the treatment of prostate cancers.


Assuntos
Azetidinas/farmacologia , Docetaxel/farmacologia , Janus Quinase 1/antagonistas & inibidores , Nitrilas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Purinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Masculino
7.
J Cell Mol Med ; 24(20): 12188-12198, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32926495

RESUMO

Prostate cancer (PCa) is the most common malignancy and is the second leading cause of cancer among men globally. Using a kinome-wide lentiviral small-hairpin RNA (shRNA) library screen, we identified phosphoinositide-dependent kinase-1 (PDPK1) as a potential mediator of cell survival in PCa cells. We showed that knock-down of endogenous human PDPK1 induced significant tumour-specific cell death in PCa cells (DU145 and PC3) but not in the normal prostate epithelial cells (RWPE-1). Further analyses revealed that PDPK1 mediates cancer cell survival predominantly via activation of serum/glucocorticoid-regulated kinase 3 (SGK3). Knock-down of endogenous PDPK1 in DU145 and PC3 cells significantly reduced SGK3 phosphorylation while ectopic expression of a constitutively active SGK3 completely abrogated the apoptosis induced by PDPK1. In contrast, no such effect was observed in SGK1 and AKT phosphorylation following PDPK1 knock-down. Importantly, PDPK1 inhibitors (GSK2334470 and BX-795) significantly reduced tumour-specific cell growth and synergized docetaxel sensitivity in PCa cells. In summary, our results demonstrated that PDPK1 mediates PCa cells' survival through SGK3 signalling and suggest that inactivation of this PDPK1-SGK3 axis may potentially serve as a novel therapeutic intervention for future treatment of PCa.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/antagonistas & inibidores , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Biblioteca Gênica , Humanos , Masculino , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiofenos/farmacologia , Tiofenos/uso terapêutico
8.
Breast Cancer Res Treat ; 179(3): 615-629, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31784862

RESUMO

PURPOSE: Breast cancer stem cells (CSCs) are a small subpopulation of cancer cells that have high capability for self-renewal, differentiation, and tumor initiation. CSCs are resistant to chemotherapy and radiotherapy, and are responsible for cancer recurrence and metastasis. METHODS: By utilizing a panel of breast cancer cells and mammospheres culture as cell-based screening platforms, we performed high-throughput chemical library screens to identify agents that are effective against breast CSCs and non-CSCs. The hit molecules were paired with conventional chemotherapy to evaluate the combinatorial treatment effects on breast CSCs and non-CSCs. RESULTS: We identified a total of 193 inhibitors that effectively targeting both breast CSCs and non-CSCs. We observed that histone deacetylase inhibitors (HDACi) synergized conventional chemotherapeutic agents (i.e., doxorubicin and cisplatin) in targeting breast CSCs and non-CSCs simultaneously. Further analyses revealed that quisinostat, a potent inhibitor for class I and II HDACs, potentiated doxorubicin-induced cytotoxicity in both breast CSCs and non-CSCs derived from the basal-like (MDA-MB-468 and HCC38), mesenchymal-like (MDA-MB-231), and luminal-like breast cancer (MCF-7). It was also observed that the basal-like breast CSCs and non-CSCs were more sensitive to the co-treatment of quisinostat with doxorubicin compared to that of the luminal-like breast cancer subtype. CONCLUSION: In conclusion, this study demonstrates the potential of HDACi as therapeutic options, either as monotherapy or in combination with chemotherapeutics against refractory breast cancer.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Doxorrubicina/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Apoptose/efeitos dos fármacos , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunofenotipagem , Bibliotecas de Moléculas Pequenas
9.
J Obstet Gynaecol Res ; 46(11): 2435-2441, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32808414

RESUMO

Accessory ovary is a type of ovarian dysplasia, which is often defined as an ovarian tissue placed near and directly connected to the normal ovary or one of ovarian ligaments. It is often asymptomatic, mostly is found or diagnosed at laparotomy, laparoscopy or autopsy. Accessory ovary is often excised during surgery due to its potential malignant behavior. We report a case of endometriosis cyst occurred simultaneously in right side of orthotopic and accessory ovaries, together with torsion 180° of accessory ovarian cyst. Considering that the patient had not given birth and the large size of cysts, exploratory laparotomy was performed. During laparotomy, both site of ovarian cyst have been removed with orthotopic and accessory ovarian tissues preserved. After surgery, a large number of antral follicles were found both in right side of orthotopic and accessory ovaries by ultrasonography. Accessory ovary is considered to have physiological function, and can be preserved as a fertility protection measure for women who have fertility requirements. At present, the definition of ectopic ovary, accessory ovary and supernumerary ovary are very vague and rarely discussed separately. So, we proposed a new way to clarify the concepts of ectopic ovary, accessory ovary and supernumerary ovary. Moreover, we advocated that they should be discussed separately in terms of definition and management measures.


Assuntos
Endometriose , Infertilidade , Laparoscopia , Cistos Ovarianos , Endometriose/complicações , Endometriose/cirurgia , Feminino , Humanos , Cistos Ovarianos/cirurgia , Ultrassonografia
10.
Appl Opt ; 58(23): 6377-6387, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503785

RESUMO

Stereo cameras are widely used in wearable visually impaired assistance devices (VIADs). However, the inevitable vibration, shock, and mechanical stress may make the camera pair become misaligned and cause a sharp decline in the quality of the acquired depth map, which significantly influences the performance of VIADs. In this paper, we propose an epipolar-constraint-based unconstrained self-calibration method that requires neither user involvement nor specific environment, while achieving a rotation accuracy of 0.83 mrad and a translation accuracy of 0.42 mm. Several approaches are proposed to address the image matching issues, including blurred images removal, mismatched key points removal, etc. Based on correctly matched key point pairs, a planar quadric-distribution approach is proposed to ensure the quality and consistency of the final key point group. These collection approaches ensure the reliability of key point pairs, which is the most important factor to realize high accuracy with minimum constraint. A comprehensive set of experiments demonstrates the high robustness of the proposed methods, which are suitable for VIADs. We also present a field test with blindfolded users to validate the flexibility and applicability of the approach.

11.
Apoptosis ; 23(5-6): 343-355, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29740790

RESUMO

Pancreatic adenocarcinoma (PDAC) is a highly aggressive cancer with a high chance of recurrence, limited treatment options, and poor prognosis. A recent study has classified pancreatic cancers into four molecular subtypes: (1) squamous, (2) immunogenic, (3) pancreatic progenitor and (4) aberrantly differentiated endocrine exocrine. Among all the subtypes, the squamous subtype has the worst prognosis. This study aims to utilize large scale genomic datasets and computational systems biology to identify potential drugs targeting the squamous subtype of PDAC through combination therapy. Using the transcriptomic data available from the International Cancer Genome Consortium, Cancer Cell Line Encyclopedia and Connectivity Map, we identified 26 small molecules that could target the squamous subtype of PDAC. Among them include inhibitors targeting the SRC proto-oncogene (SRC) and the mitogen-activated protein kinase kinase 1/2 (MEK1/2). Further analyses demonstrated that the SRC inhibitors (dasatinib and PP2) and MEK1/2 inhibitor (pimasertib) synergized gemcitabine sensitivity specifically in the squamous subtype of PDAC cells (SW1990 and BxPC3), but not in the PDAC progenitor cells (AsPC1). Further analysis revealed that the synergistic effects are dependent on SRC or MEK1/2 activities, as overexpression of SRC or MEK1/2 completely abrogated the synergistic effects SRC inhibitors (dasatinib and PP2) and MEK1/2 inhibitor (pimasertib). In contrast, no significant toxicity was observed in the MRC5 human lung fibroblast and ARPE-19 human retinal pigment epithelial cells. Together, our findings suggest that combinations of SRC or MEK inhibitors with gemcitabine possess synergistic effects on the squamous subtype of PDAC cells and warrant further investigation.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Ductal Pancreático/genética , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Desoxicitidina/uso terapêutico , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Inibidores Enzimáticos/uso terapêutico , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Transcriptoma , Gencitabina
12.
Toxicol Appl Pharmacol ; 329: 347-357, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28673683

RESUMO

Single-walled carbon nanotubes (SWCNTs) are carbon-based nanomaterials that possess immense industrial potential. Despite accumulating evidence that exposure to SWCNTs might be toxic to humans, our understanding of the mechanisms for cellular toxicity of SWCNTs remain limited. Here, we demonstrated that acute exposure of short (1-3µm) and regular-length (5-30µm) pristine, carboxylated or hydroxylated SWCNTs inhibited cell proliferation in human somatic and human stem cells in a cell type-dependent manner. The toxicity of regular-length pristine SWCNT was most evidenced in NP69>CYT00086>MCF-10A>MRC-5>HaCaT > HEK-293T>HepG2. In contrast, the short pristine SWCNTs were relatively less toxic in most of the cells being tested, except for NP69 which is more sensitive to short pristine SWCNTs as compared to regular-length pristine SWCNTs. Interestingly, carboxylation and hydroxylation of regular-length SWCNTs, but not the short SWCNTs, significantly reduced the cytotoxicity. Exposure of SWCNTs also induced caspase 3 and 9 activities, mitochondrial membrane depolarization, and significant apoptosis and necrosis in MRC-5 embryonic lung fibroblasts. In contrast, SWCNTs inhibited the proliferation of HaCaT human keratinocytes without inducing cell death. Further analyses by gene expression profiling and Connectivity Map analysis showed that SWCNTs induced a gene expression signature characteristic of heat shock protein 90 (HSP90) inhibition in MRC-5 cells, suggesting that SWCNTs may inhibit the HSP90 signaling pathway. Indeed, exposure of MRC-5 cells to SWCNTs results in a dose-dependent decrease in HSP90 client proteins (AKT, CDK4 and BCL2) and a concomitant increase in HSP70 expression. In addition, SWCNTs also significantly inhibited HSP90-dependent protein refolding. Finally, we showed that ectopic expression of HSP90, but not HSP40 or HSP70, completely abrogated the cytotoxic effects of SWCNTs, suggesting that SWCNT-induced cellular toxicity is HSP90 dependent. In summary, our findings suggest that the toxic effects of SWCNTs are mediated through inhibition of HSP90 in human lung fibroblasts and keratinocytes.


Assuntos
Ácidos Carboxílicos/toxicidade , Fibroblastos/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Queratinócitos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Fibroblastos/patologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Células Hep G2 , Humanos , Hidroxilação , Queratinócitos/metabolismo , Queratinócitos/patologia , Pulmão/metabolismo , Pulmão/patologia , Necrose , Fatores de Tempo , Transfecção
13.
J Nat Prod ; 80(10): 2734-2740, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28926237

RESUMO

Tengerensine (1), isolated as a racemate and constituted from a pair of bis-benzopyrroloisoquinoline enantiomers, and tengechlorenine (2), purified as a scalemic mixture and constituted from a pair of chlorinated phenanthroindolizidine enantiomers, were isolated from the leaves of Ficus fistulosa var. tengerensis, along with three other known alkaloids. The structures of 1 and 2 were determined by spectroscopic data interpretation and X-ray diffraction analysis. The enantiomers of 1 were separated by chiral-phase HPLC, and the absolute configurations of (+)-1 and (-)-1 were established via experimental and calculated ECD data. Compound 1 is notable in being a rare unsymmetrical cyclobutane adduct and is the first example of a dimeric benzopyrroloisoquinoline alkaloid, while compound 2 represents the first naturally occurring halogenated phenanthroindolizidine alkaloid. Compound (+)-1 displayed a selective in vitro cytotoxic effect against MDA-MB-468 cells (IC50 7.4 µM), while compound 2 showed pronounced in vitro cytotoxic activity against all three breast cancer cell lines tested (MDA-MB-468, MDA-MB-231, and MCF7; IC50 values of 0.038-0.91 µM).


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Ciclobutanos/isolamento & purificação , Ciclobutanos/farmacologia , Ficus/química , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Alcaloides/química , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/tratamento farmacológico , Cristalografia por Raios X , Ciclobutanos/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Indolizinas/química , Concentração Inibidora 50 , Isoquinolinas , Malásia , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenantrolinas/química , Folhas de Planta/química , Estereoisomerismo
14.
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
15.
Arch Toxicol ; 90(1): 103-18, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25273022

RESUMO

Carbon nanotubes (CNTs) are an important class of nanomaterials, which have numerous novel properties that make them useful in technology and industry. Generally, there are two types of CNTs: single-walled nanotubes (SWNTs) and multi-walled nanotubes. SWNTs, in particular, possess unique electrical, mechanical, and thermal properties, allowing for a wide range of applications in various fields, including the electronic, computer, aerospace, and biomedical industries. However, the use of SWNTs has come under scrutiny, not only due to their peculiar nanotoxicological profile, but also due to the forecasted increase in SWNT production in the near future. As such, the risk of human exposure is likely to be increased substantially. Yet, our understanding of the toxicological risk of SWNTs in human biology remains limited. This review seeks to examine representative data on the nanotoxicity of SWNTs by first considering how SWNTs are absorbed, distributed, accumulated and excreted in a biological system, and how SWNTs induce organ-specific toxicity in the body. The contradictory findings of numerous studies with regards to the potential hazards of SWNT exposure are discussed in this review. The possible mechanisms and molecular pathways associated with SWNT nanotoxicity in target organs and specific cell types are presented. We hope that this review will stimulate further research into the fundamental aspects of CNTs, especially the biological interactions which arise due to the unique intrinsic characteristics of CNTs.


Assuntos
Nanotubos de Carbono/toxicidade , Animais , Carga Corporal (Radioterapia) , Exposição Ambiental/efeitos adversos , Humanos , Nanotecnologia , Especificidade de Órgãos , Farmacocinética , Medição de Risco , Distribuição Tecidual , Testes de Toxicidade/métodos
16.
Apoptosis ; 20(10): 1373-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26276035

RESUMO

Metformin, an AMPK activator, has been reported to improve pathological response to chemotherapy in diabetic breast cancer patients. To date, its mechanism of action in cancer, especially in cancer stem cells (CSCs) have not been fully elucidated. In this study, we demonstrated that metformin, but not other AMPK activators (e.g. AICAR and A-769662), synergizes 5-fluouracil, epirubicin, and cyclophosphamide (FEC) combination chemotherapy in non-stem breast cancer cells and breast cancer stem cells. We show that this occurs through an AMPK-dependent mechanism in parental breast cancer cell lines. In contrast, the synergistic effects of metformin and FEC occurred in an AMPK-independent mechanism in breast CSCs. Further analyses revealed that metformin accelerated glucose consumption and lactate production more severely in the breast CSCs but the production of intracellular ATP was severely hampered, leading to a severe energy crisis and impairs the ability of CSCs to repair FEC-induced DNA damage. Indeed, addition of extracellular ATP completely abrogated the synergistic effects of metformin on FEC sensitivity in breast CSCs. In conclusion, our results suggest that metformin synergizes FEC sensitivity through distinct mechanism in parental breast cancer cell lines and CSCs, thus providing further evidence for the clinical relevance of metformin for the treatment of cancers.


Assuntos
Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Reparo do DNA/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/química , Proteínas Quinases Ativadas por AMP/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Antineoplásicos/metabolismo , Compostos de Bifenilo , Neoplasias da Mama/tratamento farmacológico , Ciclofosfamida/metabolismo , Dano ao DNA/efeitos dos fármacos , Combinação de Medicamentos , Sinergismo Farmacológico , Células-Tronco Embrionárias/metabolismo , Epirubicina/metabolismo , Feminino , Fibroblastos/metabolismo , Fluoruracila/metabolismo , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Pulmão/citologia , Pironas/farmacologia , Ribonucleotídeos/farmacologia , Tiofenos/farmacologia
17.
Lab Invest ; 94(7): 706-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24862966

RESUMO

Tumor-associated macrophages are a prominent component of lung cancer stroma and contribute to tumor progression. The protein V-set and Ig domain-containing 4 (VSIG4), a novel B7 family-related macrophage protein that has the capacity to inhibit T-cell activation, has a potential role in the development of lung cancer. In this study, 10 human non-small-cell lung cancer specimens were collected and immunohistochemically analyzed for VSIG4 expression. Results showed massive VSIG4(+) cell infiltration throughout the samples. Immunofluorescent double staining showed that VSIG4 was present on CD68(+) macrophages, but absent from CD3(+) T cells, CD31(+) endothelial cells, and CK-18(+) epithelial cells. Moreover, VSIG4 was coexpressed on B7-H1(+) and B7-H3(+) cells in these tumor specimens. Transfection of the VSIG4 gene into 293FT cells demonstrated that the VSIG4 signal could inhibit cocultured CD4(+) and CD8(+) T-cell proliferation and cytokine (IL-2 and IFN-γ) production in vitro. Interestingly, in a murine tumor model induced by Lewis lung carcinoma cell line, we found that tumors grown in VSIG4-deficient (VSIG4(-/-)) mice were significantly smaller than those found in wild-type littermates. All of these results demonstrate that macrophage-associated VSIG4 is an activator that facilitates lung carcinoma development. Specific targeting of VSIG4 may prove to be a novel, efficacious strategy for the treatment of this carcinoma.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Macrófagos/metabolismo , Receptores de Complemento/biossíntese , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos B7/metabolismo , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Feminino , Células HEK293 , Humanos , Imuno-Histoquímica , Interferon gama/metabolismo , Interleucina-2/metabolismo , Neoplasias Pulmonares/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores de Complemento/genética
18.
Gut ; 62(8): 1204-13, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22637698

RESUMO

OBJECTIVES: Fulminant viral hepatitis (FH) remains a serious clinical problem for which the underlying pathogenesis remains unclear. The B and T lymphocyte attenuator (BTLA) is an immunoglobulin-domain-containing protein that has the capacity to maintain peripheral tolerance and limit immunopathological damage during immune responses. However, its precise role in FH has yet to be investigated. DESIGN: BTLA-deficient (BTLA-/-) mice and their wild-type littermates were infected with murine hepatitis virus strain-3 (MHV-3), and the levels of tissue damage, cell apoptosis, serum liver enzymes, fibrinogen-like protein 2 (FGL2) and cytokine production were measured and compared. Survival rate was studied after MHV-3 infection with or without adoptive transferring macrophages. RESULTS: FGL2 production, liver and spleen damage, and mortality were significantly reduced in BTLA-/- mice infected with MHV-3. This effect is due to rapid, TRAIL (TNF-related apoptosis-inducing ligand)-dependent apoptosis of MHV-3-infected macrophages in BTLA-/- mice. The early loss of macrophages resulted in reduced pathogenic tumour necrosis factor α (TNFα) and FGL2 levels and lower viral titres. The importance of TNFα in MHV-3-induced pathology was demonstrated by increased mortality in TNFα-treated MHV-3-infected BTLA-/- mice, whereas TNFα-/- mice were resistant to the infection. Moreover, adoptively transferring macrophages to BTLA-/- mice caused sensitisation, whereas blocking BTLA protected wild-type mice from virus-induced FH mortality. CONCLUSIONS: BTLA promotes the pathogenesis of virus-induced FH by enhancing macrophage viability and function. Targeting BTLA may be a novel strategy for the treatment of FH.


Assuntos
Infecções por Coronavirus/imunologia , Hepatite Viral Animal/imunologia , Macrófagos/imunologia , Vírus da Hepatite Murina , Receptores Imunológicos/imunologia , Transferência Adotiva , Animais , Apoptose/imunologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/prevenção & controle , Hepatite Viral Animal/patologia , Hepatite Viral Animal/prevenção & controle , Macrófagos/patologia , Macrófagos/transplante , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Imunológicos/biossíntese , Receptores Imunológicos/deficiência , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Fator de Necrose Tumoral alfa/biossíntese
19.
Mol Immunol ; 169: 28-36, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493579

RESUMO

Our previous work has demonstrated that the tetraspan MS4A6D interacts with MHC-II to be a complex that promotes macrophage activation (Mol Immunol. 2023; 160: 121-132), however, the exact role of MS4A6D in controlling macrophage-derived inflammation is still poorly understood. Here, we showed that Ms4a6d-deficient (Ms4a6d-/-) mice manifested a lower level of footpad swelling induced by subcutaneous injection of 100 µL of 1% Carrageenan (CGN, w/v) plus CaCl2 (50 mM), a phenomenon that is similar to Nlrp3-/-, Casp-1-/-, and Ilr1-/- mice. Mechanistically, F4/80+ macrophages infiltrated in the footpad tissues of the Ms4A6d-/- mice was significantly lower than that of the WT littermates, leading to dramatically lower levels of proIL-1ß in vivo. Moreover, macrophages from Ms4a6d-/- mice also showed a dramatical reduction of Il-1ß secretion following NLRP3 inflammsome activation in vitro. Interestingly, both Ms4a6dC237G mutant (Interruption of MS4A6D homodimerization) and Ms4a6dY241G mutant (deletion of heITAM motif) mice also significantly inhibited CGN-induced footpad swelling due to lower levels of Il-1ß secretion in vivo. Collectively, MS4A6D aggravates CGN-induced footpad swelling in mice by enhancing NLRP3 inflammasome in macrophages and inducing the release of IL-1ß, indicating that MS4A6D promotes the progression of acute inflammation.


Assuntos
Macrófagos , Animais , Camundongos , Carragenina , Inflamassomos , Inflamação/induzido quimicamente , Interleucina-1beta , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética
20.
Cell Biochem Biophys ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466472

RESUMO

Hepatocellular carcinoma (HCC) remains a major global health problem with high incidence and mortality. Diagnosis of HCC at late stages and tumour heterogeneity in patients with different genetic profiles are known factors that complicate the disease treatment. HCC therapy becomes even more challenging in patients with drug resistance such as resistance to sorafenib, which is a common drug used in HCC patients. Sorafenib resistance can further aggravate HCC by regulating various oncogenic pathways such as autophagy and nuclear factor-kappa Beta (NF-ĸß) signalling. Sirtuin 1 (SIRT1), is a nicotinamide adenosine dinucleotide (NAD)-dependent histone deacetylases that regulates various metabolic and oncogenic events such as cell survival, apoptosis, autophagy, tumourigenesis, metastasis and drug resistance in various cancers, but its role in HCC, particularly in sorafenib resistance is underexplored. In this study, we generated sorafenib-resistant HepG2 and Huh-7 liver cancer cell models to investigate the role of SIRT1 and its effect on autophagy and nuclear factor-kappa Beta (NF-ĸß) signalling pathways. Western blot analysis showed increased SIRT1, altered autophagy pathway and activated NF-Ä¸ß signalling in sorafenib-resistant cells. SIRT1-silenced HCC cells demonstrated down-regulated autophagy in both parental and chemoresistant cells. This may occur through the deacetylation of key autophagy molecules such as FOXO3, beclin 1, ATGs and LC3 by SIRT1, highlighting the role of SIRT1 in autophagy induction. Silencing of SIRT1 also resulted in activated NF-Ä¸ß signalling. This is because SIRT1 failed to deacetylate p65 subunit of NF-κB, translocate the NF-κB from nucleus to cytoplasm, and suppress NF-κB activity due to the silencing. Hence, the NF-κB transcriptional activity was restored. These findings summarize the role of SIRT1 in autophagy/NF-Ä¸ß regulatory axis, with a similar trend observed in both parental and sorafenib-resistant cells. The present work promotes a better understanding of the role of SIRT1 in autophagy and NF-Ä¸ß signalling in HCC and sorafenib-resistant HCC. As some key proteins in these pathways are potential therapeutic targets, a better understanding of SIRT1/autophagy/NF-Ä¸ß axis could further improve the therapeutic strategies against HCC.

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