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1.
Indian Dermatol Online J ; 15(2): 270-273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550836

RESUMO

Nocardiosis is a rare infection due to a ubiquitous, gram-positive, weakly acid-fast, filamentous, aerobic bacteria, that are usually responsible for opportunistic infection in immunocompromised patients. Less frequently, nocardiosis can affect immunocompetent patients, causing primary cutaneous infections. Here we present a case of a 45-year-old housewife with a 12-day history of red painful nodules arranged linearly on her right upper limb, without any apparent history of injuries or comorbidities, albeit with a hobby of gardening. The unusual yet characteristic presentation, microbiological findings, and excellent response to co-trimoxazole therapy were consistent with a diagnosis of sporotrichoid primary cutaneous nocardiosis. The uncommon lymphocutaneous presentation is often misdiagnosed. Therefore, keeping a high index of suspicion in such cases is important to improve the cure rate and prevent complications.

3.
Cell Death Dis ; 12(11): 1053, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741022

RESUMO

Currently, no frontline treatment is effective for the late-stage colorectal cancer (CRC). Understanding the molecular differences in different stages of CRC can help us to identify the critical therapeutic targets for designing therapeutic strategy. Our data show that c-Myc protein is highly expressed in late-stage CRC when compared with early-stage CRC in both clinical samples and in cell lines representing different cancer stages. Given that c-Myc is a well-known oncogenic driver in CRC, its high expression in the late-stage CRC may represent a critical therapeutic target for treating the cancer. Dihydroartemisinin treatment significantly increases c-Myc protein degradation and hence reduces its expression in CRC. The treatment also reduces CRC cell viability. Interestingly, dihydroartemisinin exhibits a more potent growth-inhibitory effect in late-stage CRC than the early-stage CRC. The treatment also possesses potent growth-inhibitory effects in mouse models bearing c-Myc-overexpressed CRC. The reduced c-Myc level and its reduced transcriptional activity reduce the expressions of acetyl-CoA carboxylase, fatty acid synthase, carnitine-palmitoyltransferase-1, and medium-chain acyl-CoA dehydrogenase in the cancer cells. Lipidomics study also shows that dihydroartemisinin treatment changes the metabolic phenotypes in CRC, reduces oxygen consumption, respiration, and ATP production, hence reduces the cell proliferation and induces apoptosis. Our study provides strong pharmacological evidence to support the translation of dihydroartemisinin for the treatment of late-stage CRC by targeting c-Myc.


Assuntos
Artemisininas/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Ácidos Graxos/análise , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Antígeno Ki-67/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Medições Luminescentes , Camundongos Endogâmicos BALB C , Camundongos Nus , Estadiamento de Neoplasias , Fenótipo , Análise de Componente Principal , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transcrição Gênica/efeitos dos fármacos
4.
Cell Death Dis ; 12(8): 791, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385421

RESUMO

Although high-fat diet (HFD) has been implicated in the development of colorectal cancer (CRC), the critical signaling molecule that mediates the cancer growth is not well-defined. Identifying the master regulator that controls CRC growth under HFD can facilitate the development of effective therapeutics for the cancer treatment. In this study, the global lipidomics and RNA sequencing data show that, in the tumor tissues of CRC-bearing mouse models, HFD not only increases tumor weight, but also the palmitic acid level and TLR4 expression, which are reduced when HFD is replaced by control diet. These concomitant changes suggest the roles of palmitic acid and TLR4 in CRC growth. Subsequent studies show that palmitic acid regulates TLR4 expression in PU.1-dependent manner. Knockdown of PU.1 or mutations of PU.1-binding site on TLR4 promoter abolish the palmitic acid-increased TLR4 expression. The role of palmitic acid/PU.1/TLR4 axis in CRC growth is further examined in cell model and animal models that are fed either HFD or palmitic acid-rich diet. More importantly, iTRAQ proteomics data show that knockdown of TLR4 changes the metabolic enzyme profiles in the tumor tissues, which completely abolish the HFD-enhanced ATP production and cancer growth. Our data clearly demonstrate that TLR4 is a master regulator for CRC growth under HFD by programming cancer metabolism.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Dieta Hiperlipídica , Receptor 4 Toll-Like/metabolismo , Animais , Sítios de Ligação , Peso Corporal , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Modelos Animais de Doenças , Comportamento Alimentar , Humanos , Linfócitos do Interstício Tumoral , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Fator 88 de Diferenciação Mieloide/metabolismo , Ácido Palmítico/toxicidade , Análise de Componente Principal , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Interleucina-1/metabolismo , Receptor 4 Toll-Like/genética , Transativadores/metabolismo
5.
Pharmacol Res ; 152: 104586, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31877350

RESUMO

Visceral obesity is the excess deposition of visceral fat within the abdominal cavity that surrounds vital organs. Visceral obesity is directly associated with metabolic syndrome, breast cancer and endometrial cancer. In visceral obese subjects, signal transducer and activator of the transcription 3 (STAT3) in adipocytes is constitutively active. In this study, we aimed to screen for dietary herbal compounds that possess anti-visceral obesity effect. Apigenin is abundant in fruits and vegetables. Our data show that apigenin significantly reduces body weight and visceral adipose tissue (VAT), but not subcutaneous (SAT) and epididymal adipose tissues (EAT), of the high fat diet (HFD)-induced obese mice. Mechanistic studies show that HFD increases STAT3 phosphorylation in VAT, but not in SAT and EAT. Further studies suggest that apigenin binds to non-phosphorylated STAT3, reduces STAT3 phosphorylation and transcriptional activity in VAT, and consequently reduces the expression of STAT3 target gene cluster of differentiation 36 (CD36). The reduced CD36 expression in adipocytes reduces the expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) which is the critical nuclear factor in adipogenesis. Our data show that apigenin reduces CD36 and PPAR-γ expressions and inhibits adipocyte differentiation; overexpression of constitutive active STAT3 reverses the apigenin-inhibited adipogenesis. Taken together, our data suggest that apigenin inhibits adipogenesis via the STAT3/CD36 axis. Our study has delineated the mechanism of action underlying the anti-visceral obesity effect of apigenin, and provide scientific evidence to support the development of apigenin as anti-visceral obesity therapeutic agent.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Apigenina/uso terapêutico , Antígenos CD36/metabolismo , Obesidade Abdominal/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Células 3T3-L1 , Tecido Adiposo/efeitos dos fármacos , Animais , Fármacos Antiobesidade/farmacologia , Apigenina/farmacologia , Peso Corporal/efeitos dos fármacos , Antígenos CD36/genética , Dieta Hiperlipídica , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Obesidade Abdominal/metabolismo , Fator de Transcrição STAT3/genética
6.
Cell Death Dis ; 10(10): 711, 2019 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558710

RESUMO

Epidemiology studies indicate that consumption of high-fat diet (HFD) is directly associated with the development of colorectal cancer (CRC). However, the exact component in HFD and the mechanism underlying its effect on CRC growth remained unclear. Our study shows that HFD feeding increases ß2AR expression in the xenograft tissues of CRC-bearing mouse model; the elevated ß2AR expression is reduced when HFD is replaced by control diet, which strongly suggests an association between HFD feeding and ß2AR expression in CRC. HFD feeding increases palmitic acid and stearic acid levels in CRC; however, only palmitic acid increases ß2AR expression, which is dependent upon Sp1. ß2AR plays the dominant role in promoting CRC cell proliferation among all the ß-AR subtypes. More importantly, knockout of ß2AR or knockdown of Sp1 abolishes the palmitic acid increased CRC cell proliferation, suggesting palmitic acid increases CRC cell proliferation in ß2AR-dependent manner. HFD or palmitic acid-rich diet (PAD) also fails to increase the tumor growth in xenograft mouse models bearing ß2AR-knockout CRC cells. ß2AR promotes CRC growth by increasing the phosphorylation of HSL at the residue S552. The phosphorylated and activated HSL (S552) changes the metabolic phenotype of CRC and increases energy production, which promotes CRC growth. Our study has revealed the unique tumorigenic properties of palmitic acid in promoting CRC growth, and have delineated the underlying mechanism of action. We are also the first to report the linkage between HFD feeding and ß-adrenergic signaling pathway in relation to CRC growth.


Assuntos
Neoplasias Colorretais/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácido Palmítico/metabolismo , Receptores Adrenérgicos beta/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Biologia Computacional , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Nus , Ácido Palmítico/farmacologia , Fosforilação , RNA Interferente Pequeno , Receptores Adrenérgicos beta/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Ácidos Esteáricos/metabolismo , Esterol Esterase/química , Esterol Esterase/metabolismo
7.
Cell Death Dis ; 10(9): 637, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31474764

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer death in men. PCa progression can be associated with obesity. Signal transducer and activator of transcription-3 (STAT3) plays a crucial role in PCa growth. However, whether STAT3 plays a role in high-fat diet (HFD)-associated PCa growth is unknown. Our data show that HFD feeding increases tumor size, STAT3 phosphorylation, and palmitic acid (PA) level in the xenograft tissues of the PCa-bearing xenograft mouse model. In vitro studies show that PA increases STAT3 expression and phosphorylation (STAT3-Y705) in PCa. Computational modeling suggests strong and stable binding between PA and unphosphorylated STAT3 at R593 and N538. The binding changes STAT3 structure and activity. Functional studies show that both STAT3 mutants (R583A and N538A) and STAT3 dominant negative significantly reduce PA-enhanced STAT3 phosphorylation, PA-increased PCa cell proliferation, migration, and invasion. In the xenograft mouse models, the HFD-increased tumor growth and STAT3 phosphorylation in tumors are reversed by STAT3 inhibition. Our study not only demonstrates the regulatory role of PA/STAT3 axis in HFD-associated PCa growth but also suggests a novel mechanism of how STAT3 is activated by PA. Our data suggest STAT3 as a therapeutic target for the treatment of HFD-associated PCa.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Xenoenxertos , Humanos , Masculino , Camundongos , Células PC-3 , Neoplasias da Próstata/etiologia , Neoplasias de Próstata Resistentes à Castração/etiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia
8.
Cell Mol Life Sci ; 76(13): 2547-2557, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30968170

RESUMO

Emerging evidence shows that palmitic acid (PA), a common fatty acid in the human diet, serves as a signaling molecule regulating the progression and development of many diseases at the molecular level. In this review, we focus on its regulatory roles in the development of five pathological conditions, namely, metabolic syndrome, cardiovascular diseases, cancer, neurodegenerative diseases, and inflammation. We summarize the clinical and epidemiological studies; and also the mechanistic studies which have identified the molecular targets for PA in these pathological conditions. Activation or inactivation of these molecular targets by PA controls disease development. Therefore, identifying the specific targets and signaling pathways that are regulated by PA can give us a better understanding of how these diseases develop for the design of effective targeted therapeutics.


Assuntos
Autofagia , Doenças Cardiovasculares/patologia , Inflamação/patologia , Síndrome Metabólica/patologia , Neoplasias/patologia , Doenças Neurodegenerativas/patologia , Ácido Palmítico/metabolismo , Animais , Doenças Cardiovasculares/metabolismo , Humanos , Inflamação/metabolismo , Síndrome Metabólica/metabolismo , Neoplasias/metabolismo , Doenças Neurodegenerativas/metabolismo , Transdução de Sinais
9.
Chem Sci ; 9(5): 1119-1125, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29675156

RESUMO

Dopamine receptor expression is correlated with certain types of cancers, including lung, breast and colon cancers. In this study, we report luminescent iridium(iii) complexes (11-14) as intracellular dopamine receptor (D1R/D2R) cell imaging agents. Complexes 11 and 13, which are conjugated with a dopamine receptor agonist, showed superior cell imaging characteristics, high stability and low cytotoxicity (>100 µM) in A549 lung cancer cells. siRNA knockdown and dopamine competitive assays indicated that complexes 11 and 13 could selectively bind to dopamine receptors (D1R/D2R) in A549 cells. Fluorescence lifetime microscopy demonstrated that complex 13 has a longer luminescence lifetime at the wavelength of 560-650 nm than DAPI and other chromophores in biological fluids. The long luminescence lifetime of complex 13 not only provides an opportunity for efficient dopamine receptor tracking in biological media, but also enables the temporal separation of the probe signal from the intense background signal by fluorescence lifetime microscopy for efficient analysis. Complex 13 also shows high photostability, which could allow it to be employed for long-term cellular imaging. Furthermore, complex 13 could selectively track the internalization process of dopamine receptors (D1R/D2R) in living cells. To the best of our knowledge, complex 13 is the first metal-based compound that has been used to monitor intracellular dopamine receptors in living cells.

10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3224-3227, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060584

RESUMO

Brain decoding is essential in understanding where and how information is encoded inside the brain. Existing literature has shown that a good classification accuracy is achievable in decoding for single subjects, but multi-subject classification has proven difficult due to the inter-subject variability. In this paper, multi-modal neuroimaging was used to improve two-class multi-subject classification accuracy in a cognitive task of differentiating between a face and a scrambled face. In this transfer learning problem, a feature space based on special-form covariance matrices manipulated with riemannian geometry are used. A supervised two-layer hierarchical model was trained iteratively for estimating classification accuracies. Results are reported on a publically available multi-subject, multi-modal human neuroimaging dataset from MRC Cognition and Brain Sciences Unit, University of Cambridge. The dataset contains simultaneous recordings of electroencephalography (EEG) and magnetoencephalography (MEG). Our model attained, using leave-one-subject-out cross-validation, a classification accuracy of 70.82% for single modal EEG, 81.55% for single modal MEG and 84.98% for multi-modal M/EEG.


Assuntos
Eletroencefalografia , Encéfalo , Mapeamento Encefálico , Cognição , Humanos , Magnetoencefalografia , Neuroimagem
11.
Front Pharmacol ; 8: 277, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28567017

RESUMO

Recent studies indicate that mitochondrial pathways of apoptosis are potential chemotherapeutic target for the treatment of esophageal cancer. Azoxystrobin (AZOX), a methoxyacrylate derived from the naturally occurring strobilurins, is a known fungicide acting as a ubiquinol oxidation (Qo) inhibitor of mitochondrial respiratory complex III. In this study, the effects of AZOX on human esophageal squamous cell carcinoma KYSE-150 cells were examined and the underlying mechanisms were investigated. AZOX exhibited inhibitory effects on the proliferation of KYSE-150 cells with inhibitory concentration 50% (IC50) of 2.42 µg/ml by 48 h treatment. Flow cytometry assessment revealed that the inhibitory effect of AZOX on KYSE-150 cell proliferation occurred with cell cycle arrest at S phase and increased cell apoptosis in time-dependent and dose-dependent manners. Cleaved poly ADP ribose polymerase (PARP), caspase-3 and caspase-9 were increased significantly by AZOX. It is worth noted that the Bcl-2/Bax ratios were decreased because of the down-regulated Bcl-2 and up-regulated Bax expression level. Meanwhile, the cytochrome c release was increased by AZOX in KYSE-150 cells. AZOX-induced cytochrome c expression and caspase-3 activation was significantly blocked by Bax Channel Blocker. Intragastric administration of AZOX effectively decreased the tumor size generated by subcutaneous inoculation of KYSE-150 cells in nude mice. Consistently, decreased Bcl-2 expression, increased cytochrome c and PARP level, and activated caspase-3 and caspase-9 were observed in the tumor samples. These results indicate that AZOX can effectively induce esophageal cancer cell apoptosis through the mitochondrial pathways of apoptosis, suggesting AZOX or its derivatives may be developed as potential chemotherapeutic agents for the treatment of esophageal cancer.

12.
Pharmacol Res ; 110: 227-239, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26969793

RESUMO

Ulcerative colitis (UC) is an increasingly common condition particularly in developed countries. The lack of satisfactory treatment has fueled the search for alternative therapeutic strategies. In recent studies, berberine, a plant alkaloid with a long history of medicinal use in Chinese medicine, has shown beneficial effects against animal models of acute UC. However, UC usually presents as a chronic condition with frequent relapse in patients. How berberine will act on chronic UC remains unclear. In the present study, we adopted dextran sulfate sodium (DSS)-induced chronic relapsing colitis model to assess the ameliorating activity of berberine. Colitis was induced by two cycles of 2.0% DSS for five days followed by 14days of drinking water plus a third cycle consisting of DSS only for five days. The colitis mice were orally administered 20mg/kg berberine from day 13 onward for 30days and monitored daily. The body weight, stool consistency, and stool bleeding were recorded for determination of the disease activity index (DAI). At the end of treatment, animals were sacrificed and samples were collected and subjected to histological, RT-qPCR, Western blot, and LC-MS analyses. Lymphocytes were isolated from spleens and mesenteric lymph nodes (MLN) and cultured for flow cytometry analysis of IL-17 secretion from CD4(+) cells and the Th17 cell differentiation. Results showed that berberine significantly ameliorated the DAI, colon shortening, colon tissue injury, and reduction of colonic expression of tight junction (TJ) protein ZO-1 and occludin of colitis mice. Notably, berberine treatment pronouncedly reduced DSS-upregulated Th17-related cytokine (IL-17 and ROR-γt) mRNAs in the colon. Furthermore, the mRNA expression of IL-6 and IL-23, and the phosphorylation of STAT3 in colon tissues from DSS-treated mice were pronouncedly inhibited by berberine. Moreover, the up-regulation of IL-17 secretion from CD4(+) cells of spleens and MLNs caused by DSS were significantly reversed by berberine treatment. Furthermore, Th17 cell differentiation from naive CD4(+) cells isolated from above DSS colitis mice were suppressed by berberine in a concentration-dependent manner. In summary, we demonstrated for the first time that berberine reduced the severity of chronic relapsing DSS-induced colitis by suppressing Th17 responses. The demonstration of activity in this mouse model supports the possibility of clinical efficacy of berberine in treating chronic UC.


Assuntos
Berberina/farmacologia , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfato de Dextrana , Fármacos Gastrointestinais/farmacologia , Interleucina-17/metabolismo , Células Th17/efeitos dos fármacos , Animais , Células Cultivadas , Doença Crônica , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/metabolismo , Colo/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Imunossupressores/farmacologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-23/genética , Interleucina-23/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recidiva , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Th17/imunologia , Células Th17/metabolismo , Fatores de Tempo
13.
J Nat Prod ; 79(4): 1056-62, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26905227

RESUMO

The immunoregulatory protective properties of (+)-3'α-angeloxy-4'-keto-3',4'-dihydroseselin (Pd-Ib) isolated from Bupleurum malconense has not been reported. In the present study, the therapeutic effect of Pd-Ib (30, 60, and 120 mg/kg/day) was examined in a mouse model of dextran sulfate sodium (DSS)-induced acute colitis. Administration of Pd-Ib significantly reduced the disease activity index, inhibited the shortening of colon length, reduced colonic tissue damage, and suppressed colonic myeloperoxidase activity and nitric oxide levels in mice with DSS-induced colitis. Moreover, Pd-Ib greatly suppressed the secretion of pro-inflammatory cytokines TNF-α, IFN-γ, IL-6, and IL-17A while enhancing the level of anti-inflammatory cytokine IL-4. The protein levels of phosphorylated STAT3 (p-STAT3) and phosphorylated p38 (p-p38) were down-regulated in the colonic tissues of DSS-treated mice. Importantly, the anti-inflammatory effect of Pd-Ib against acute colitis was comparable to the anti-inflammatory sulfa drug sulfasalazine (300 mg/kg). Furthermore, the in vitro study showed that the inhibitory effect of Pd-Ib on p-STAT3 and IL-6 protein levels was accompanied by the reduction of MAPKs (JNK and p38). In conclusion, this study suggested that Pd-Ib attenuated DSS-induced acute colitis via the regulation of interleukins principally through the STAT3 and MAPK pathways.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Bupleurum/química , Colite/induzido quimicamente , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Sulfato de Dextrana/efeitos adversos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Colo/efeitos dos fármacos , Cumarínicos/administração & dosagem , Cumarínicos/química , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-17/uso terapêutico , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinases de Proteína Quinase Ativadas por Mitógeno/efeitos dos fármacos , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição STAT3/efeitos dos fármacos , Estereoisomerismo , Sulfassalazina/farmacologia
14.
Mol Oncol ; 10(2): 195-212, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26474915

RESUMO

5-Hydroxytryptamine (5-HT), a neurotransmitter and vasoactive factor, has been reported to promote proliferation of serum-deprived hepatocellular carcinoma (HCC) cells but the detailed intracellular mechanism is unknown. As Wnt/ß-catenin signalling is highly dysregulated in a majority of HCC, this study explored the regulation of Wnt/ß-catenin signalling by 5-HT. The expression of various 5-HT receptors was studied by quantitative real-time polymerase chain reaction (qPCR) in HCC cell lines as well as in 33 pairs of HCC tumours and corresponding adjacent non-tumour tissues. Receptors 5-HT1D (21/33, 63.6%), 5-HT2B (12/33, 36.4%) and 5-HT7 (15/33, 45.4%) were overexpressed whereas receptors 5-HT2A (17/33, 51.5%) and 5-HT5 (30/33, 90.1%) were reduced in HCC tumour tissues. In vitro data suggests 5-HT increased total ß-catenin, active ß-catenin and decreased phosphorylated ß-catenin protein levels in serum deprived HuH-7 and HepG2 cells compared to control cells under serum free medium without 5-HT. Activation of Wnt/ß-catenin signalling was evidenced by increased expression of ß-catenin downstream target genes, Axin2, cyclin D1, dickoppf-1 (DKK1) and glutamine synthetase (GS) by qPCR in serum-deprived HCC cell lines treated with 5-HT. Additionally, biochemical analysis revealed 5-HT disrupted Axin1/ß-catenin interaction, a critical step in ß-catenin phosphorylation. Increased Wnt/ß-catenin activity was attenuated by antagonist of receptor 5-HT7 (SB-258719) in HCC cell lines and patient-derived primary tumour tissues in the presence of 5-HT. SB-258719 also reduced tumour growth in vivo. This study provides evidence of Wnt/ß-catenin signalling activation by 5-HT and may represent a potential therapeutic target for hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/patologia , Proliferação de Células , Neoplasias Hepáticas/patologia , Serotonina/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Animais , Proteína Axina/metabolismo , Carcinogênese/metabolismo , Carcinoma Hepatocelular/metabolismo , Ciclina D1/metabolismo , Feminino , Glutamato-Amônia Ligase/metabolismo , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Fosforilação , Piperidinas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Sulfonamidas/farmacologia , beta Catenina/química
15.
Oncotarget ; 6(27): 24148-62, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26160839

RESUMO

The Akt/mTORC1 pathway plays a central role in the activation of Warburg effect in cancer. Here, we present for the first time that halofuginone (HF) treatment inhibits colorectal cancer (CRC) growth both in vitro and in vivo through regulation of Akt/mTORC1 signaling pathway. Halofuginone treatment of human CRC cells inhibited cell proliferation, induced the generation of reactive oxygen species and apoptosis. As expected, reduced level of NADPH was also observed, at least in part due to inactivation of glucose-6-phosphate dehydrogenase in pentose phosphate pathway upon HF treatment. Given these findings, we further investigated metabolic regulation of HF through Akt/mTORC1-mediated aerobic glycolysis and found that HF downregulated Akt/mTORC1 signaling pathway. Moreover, metabolomics delineated the slower rates in both glycolytic flux and glucose-derived tricarboxylic acid cycle flux. Meanwhile, both glucose transporter GLUT1 and hexokinase-2 in glycolysis were suppressed in CRC cells upon HF treatment, to support our notion that HF regulates Akt/mTORC1 signaling pathway to dampen glucose uptake and glycolysis in CRC cells. Furthermore, HF retarded tumor growth in nude mice inoculated with HCT116 cells, showing the anticancer activity of HF through metabolic regulation of Akt/mTORC1 in CRC.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Glucose/metabolismo , Complexos Multiproteicos/metabolismo , Piperidinas/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinonas/química , Serina-Treonina Quinases TOR/metabolismo , Animais , Antineoplásicos/química , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Feminino , Transportador de Glucose Tipo 1/metabolismo , Glicólise , Células HCT116 , Hexoquinase/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas , Lipídeos/química , Alvo Mecanístico do Complexo 1 de Rapamicina , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Via de Pentose Fosfato , Inibidores da Síntese de Proteínas/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
16.
Expert Rev Mol Diagn ; 14(5): 535-48, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24809435

RESUMO

The prognosis for hepatocellular carcinoma (HCC) remains dismal due to the lack of diagnostic markers for early detection. This review will discuss the clinical potential of the dickkopf (DKK) family members as diagnostic and/or prognostic markers for HCC. In comparison to serum α-fetoprotein (AFP) level, which remains the gold standard for HCC diagnosis, high serum DKK1 levels have higher diagnostic value for HCC, especially for AFP-negative HCC, and can distinguish HCC from non-malignant chronic liver diseases. Additionally, the combination of serum DKK1 and AFP levels enhances diagnostic accuracy for HCC compared to serum DKK1 or AFP levels alone. Although DKK1 offers potential for its use in HCC diagnosis this review will discuss the challenges facing DKK1 and also shed some light on recent developments on the remaining DKK family members: DKK2, DKK3 and DKK4.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
17.
Int J Hepatol ; 2012: 760928, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029619

RESUMO

Hepatocellular carcinoma (HCC) is a primary liver malignancy and accounts for most of the total liver cancer cases. Lack of treatment options and late diagnosis contribute to high mortality rate of HCC. In eukaryotes, translation of messenger RNA (mRNA) to protein is a key process in protein biosynthesis in which initiation of translation involves interaction of different eukaryotic translation initiation factors (eIFs), ribosome subunits and mRNAs. Eukaryotic translation initiation factor 5A (eIF5A) is one of the eIFs involved in translation initiation and eIF5A2, one of its isoforms, is upregulated in various cancers including HCC as a result of chromosomal instability, where it resides. In HCC, eIF5A2 expression is associated with adverse prognosis such as presence of tumor metastasis and venous infiltration. Based on eIF5A2 functional studies, suppressing eIF5A2 expression by short interfering RNA alleviates the tumorigenic properties of HCC cells in vitro while ectopic expression of eIF5A2 enhances the aggressiveness of HCC cells in vivo and in vitro by inducing epithelial-mesenchymal transition. In conclusion, eIF5A2 is a potential prognostic marker as well as a therapeutic target for HCC.

18.
Liver Int ; 31(10): 1494-504, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21955977

RESUMO

BACKGROUND: Although Dickkopf-1 (DKK1) is known to be a negative regulator of the Wnt/ß-catenin pathway, it has been recently found to be upregulated in cancers. AIMS: We investigated the clinical and prognostic significance of both serum and transcript DKK1 and its functional roles in human hepatocellular carcinoma (HCC). METHODS: We evaluated the expression level of DKK1 in both tissue and serum samples from patients with HCC using GeneChip microarray and real-time-quantitative PCR and sandwich ELISA system respectively. The clinicopathological and prognostic significance of serum and tissue DKK1 levels was examined. Functional characterization of DKK1 with regard to cell migration, invasion and tumour growth was performed. RESULTS: Both DKK1 transcript and serum protein were upregulated in a stepwise manner in human HCCs. Its transcript levels were associated with more aggressive tumour behaviour, in terms of venous invasion (P = 0.003), advanced tumour stage (P = 0.003). DKK1 transcript correlated with shorter overall (P = 0.006) and disease-free survival (P = 0.012), and higher serum DKK1 levels correlated with shorter disease-free survival (P = 0.046). Knockdown of DKK1 significantly reduced both migratory and invasive abilities of HCC cells, whereas overexpression of DKK1 enhanced the tumour formation efficiency and tumour growth in vivo. CONCLUSIONS: Serum and tissue DKK1 levels increased in a stepwise manner in multistep hepatocarcinogenesis and had prognostic significance. DKK1 plays a functional role in cell migration, invasion and tumour growth.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Silenciamento de Genes , Hong Kong , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/fisiopatologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas
19.
World J Clin Oncol ; 2(8): 311-25, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21876852

RESUMO

Liver cancer is the fifth and seventh most common cause of cancer in men and women, respectively. Wnt/ß-catenin signalling has emerged as a critical player in both the development of normal liver as well as an oncogenic driver in hepatocellular carcinoma (HCC). Based on the current understanding, this article summarizes the possible mechanisms for the aberrant activation of this pathway with specific focus on HCC. Furthermore, we will discuss the role of dickkopfs (DKKs) in regulating Wnt/ß-catenin signalling, which is poorly understood and understudied. DKKs are a family of secreted proteins that comprise at least four members, namely DKK1-DKK4, which act as inhibitors of Wnt/ß-catenin signalling. Nevertheless, not all members antagonize Wnt/ß-catenin signalling. Their functional significance in hepatocarcinogenesis remains to be further characterized for which these studies should provide new insights into the regulatory role of DKKs in Wnt/ß-catenin signalling in hepatic carcinogenesis. Because of the important oncogenic roles, there are an increasing number of therapeutic molecules targeting ß-catenin and the Wnt/ß-catenin pathway for potential therapy of HCC.

20.
Protein Pept Lett ; 16(5): 467-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19442224

RESUMO

The need to identify disease biomarkers is critical to ensure fast diagnosis and timely treatment. Surface enhanced laser desorption/ionization time-of-fight mass spectrometry (SELDI-TOF-MS) is a widely used technology platform for diagnostic biomarker discovery. This short review provides an overview of how it functions and also describes its advantages and drawbacks.


Assuntos
Análise Química do Sangue/métodos , Hepatopatias/sangue , Espectrometria de Massas/métodos , Análise Serial de Proteínas/métodos , Biomarcadores/sangue , Análise Química do Sangue/instrumentação , Humanos , Espectrometria de Massas/instrumentação , Análise Serial de Proteínas/instrumentação , Propriedades de Superfície
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