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1.
Chem Res Toxicol ; 28(9): 1681-92, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26275128

RESUMO

The induction of detoxifying enzymes and antioxidant proteins by chemopreventive agents protects cells from oxidizing substances capable of damaging DNA integrity and initiating carcinogenesis. Coniferyl aldehyde, a naturally occurring substance, has been found in many foods and edible plants. We and others previously demonstrated that trans-coniferylaldehyde (t-CA) has potential antimutagenic and antioxidant properties. However, the mechanism underlying its Nrf2-mediated antioxidant effect remains largely unknown. In the present study, we demonstrated that t-CA significantly stimulated antioxidant-responsive element (ARE)-driven luciferase activity in a cell model and increased the expression of ARE-dependent detoxifying/antioxidant genes and their protein products in vitro and in vivo. The detoxifying/antioxidant genes activated by t-CA, especially heme oxygenase-1 (HO-1), were found to be involved in its cytoprotective effects against oxidative stress and cell injuries elicited by carcinogens tert-butylhydroperoxide and arecoline. Furthermore, the t-CA-induced phosphorylation and nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) played a crucial role in this ARE-mediated cellular defense. Moreover, we found that p38 MAPK and protein kinase C (PKC) signaling pathways participated in the t-CA-induced, Nrf2-mediated cytoprotective effect. Among them, p38α/MAPKAPK-2 and an atypical PKC, PK-N3, were critical for the activation of the Nrf2/HO-1 axis by t-CA. In conclusion, we demonstrated for the first time that t-CA attenuates carcinogen-induced oxidative stress by activating Nrf2 via p38α/MAPKAPK-2- and PK-N3-dependent signaling pathways. In addition, t-CA increased the level of Nrf2-mediated detoxifying/antioxidant proteins in vivo, suggesting that t-CA may have potential for use in the management of carcinogenesis and meriting further investigation.


Assuntos
Acroleína/análogos & derivados , Heme Oxigenase-1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Acroleína/farmacologia , Animais , Camundongos , Camundongos Endogâmicos C57BL
2.
Bioorg Med Chem ; 23(13): 3852-9, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25907366

RESUMO

Recent studies have demonstrated that oxidative stress insult is one of major causes of tumor formation. Therefore, identify the effective anti-oxidative agents as a preventive approach to stop cancer progression has widely explored. Although, many potent anti-oxidative ingredients in the natural products have been identified but the amount from the nature source hindrances the clinical application. Compound which can activate Nrf2 signaling pathway result unregulated the cellular antioxidant-responses has been demonstrated as an effective chemopreventive approach for cancer treatment. In the present study, certain oxime-bearing naphthalene derivatives were synthesized and evaluated for their Nrf2 activation and anti-proliferative activities. Results indicated (E)-1-(naphthalen-2-yloxy)propan-2-one oxime (11) which increased 2.04-fold Nrf2/ARE-driven luciferase activity was more active than its 1-substituted isomer 10 (1.17-fold) and t-BHQ (1.77-fold), the known Nrf2 activator. The activities were further increased by the replacement of the peripheral methyl group with the phenyl ring in which (Z)-2-(naphthalen-2-yloxy)-1-phenylethanone oxime (13a) exhibited 3.49-fold potency of the positive control. It is worth to mention that compounds 11, 13a, and 13b which showed significant Nrf2 activation are non-cytotoxic to the tested cells with IC50>50µM. This observation strongly suggested that these compounds can be used for chemoprevention. Mechanism studies indicated that these compounds were capable of inducing the phosphorylation of Nrf2 protein at serine 40 which led to the activation of the Nrf2 transcriptional activity.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Fator 2 Relacionado a NF-E2/agonistas , Naftalenos/farmacologia , Oximas/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Naftalenos/síntese química , Estresse Oxidativo , Oximas/síntese química , Fosforilação/efeitos dos fármacos , Transdução de Sinais , Relação Estrutura-Atividade
3.
Chem Pharm Bull (Tokyo) ; 62(1): 106-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24390500

RESUMO

Certain amide-containing anthraquinone, xanthone, and carbazole derivatives have been synthesized and evaluated in vitro for their antiproliferative activities against a panel of human cancer cell lines including nasopharyngeal carcinoma (NPC-TW01), lung carcinoma (NCI-H661), and leukemia (Jurkat). Among them, 2-(9,10-dioxo-9,10-dihydroanthracen-2-yloxy)-N-(naphthalen-2-yl)acetamide (13) was the most active against NPC-TW01 with an IC50 value of 2.62 µM while its xanthone and dibenzofuran counterparts, 14 and 15, were inactive with an IC50 value of 16.10 and 11.09 µM, respectively. Studies on NPC-TW01 cell cycle distribution revealed that compound 13 inhibited proliferation of NPC-TW01 by the alteration of cell division and the accumulation of cells in G0/G1 phase.


Assuntos
Amidas/química , Antraquinonas/química , Carbazóis/química , Proliferação de Células/efeitos dos fármacos , Xantonas/química , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Humanos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos
4.
Microorganisms ; 12(5)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38792777

RESUMO

Since the onset of the COVID-19 pandemic in 2019, the role of weather conditions in influencing transmission has been unclear, with results varying across different studies. Given the changes in border policies and the higher vaccination rates compared to earlier conditions, this study aimed to reassess the impact of weather on COVID-19, focusing on local climate effects. We analyzed daily COVID-19 case data and weather factors such as temperature, humidity, wind speed, and a diurnal temperature range from 1 March to 15 August 2022 across six regions in Taiwan. This study found a positive correlation between maximum daily temperature and relative humidity with new COVID-19 cases, whereas wind speed and diurnal temperature range were negatively correlated. Additionally, a significant positive correlation was identified between the unease environmental condition factor (UECF, calculated as RH*Tmax/WS), the kind of Climate Factor Complex (CFC), and confirmed cases. The findings highlight the influence of local weather conditions on COVID-19 transmission, suggesting that such factors can alter environmental comfort and human behavior, thereby affecting disease spread. We also introduced the Fire-Qi Period concept to explain the cyclic climatic variations influencing infectious disease outbreaks globally. This study emphasizes the necessity of considering both local and global climatic effects on infectious diseases.

5.
Int J Health Geogr ; 12: 25, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23648001

RESUMO

BACKGROUND: There are many applications for spatial cluster detection and more detection methods have been proposed in recent years. Most cluster detection methods are efficient in detecting circular (or circular-like) clusters, but the methods which can detect irregular-shaped clusters usually require a lot of computing time. METHODS: We propose a new spatial detection algorithm for lattice data. The proposed method can be separated into two stages: the first stage determines the significant cells with unusual occurrences (i.e., individual clustering) by applying the Choynowski's test, and the second stage determines if there are clusters based on the information of the first stage by a binomial approximate method. We first use computer simulation to evaluate the performance of the proposed method and compare it with the scan statistics. Furthermore, we take the Taiwan Cancer data in 2000 to illustrate the detection results of the scan statistics and the proposed method. RESULTS: The simulation results support using the proposed method when the population sizes are large and the study regions are irregular. However, in general, the scan statistics still have better power in detecting clusters, especially when the population sizes are not large. For the analysis of cancer data, the scan statistics tend to spot more clusters, and the clusters' shapes are close to circular (or elliptic). On the other hand, the proposed methods only find one cluster and cannot detect small-sized clusters. CONCLUSIONS: In brief, the proposed methods can detect both circular and non-circular clusters well when the significant cells are correctly detected by the Choynowski's method. In addition, the binomial-based method can handle the problem of multiple testing and save the computing time. On the other hand, both the circular and elliptical scan statistics have good power in detecting clusters, but tend to detect more clusters and have lower accuracy in detecting non-circular clusters.


Assuntos
Simulação por Computador , Surtos de Doenças/estatística & dados numéricos , Neoplasias/epidemiologia , Análise Espacial , Análise por Conglomerados , Feminino , Humanos , Masculino , Neoplasias/diagnóstico , Taiwan/epidemiologia
6.
Chem Biodivers ; 10(10): 1903-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24130033

RESUMO

Two new pterosin sesquiterpenes, (2S)-13-hydroxypterosin A (1) and (2S,3S)-12-hydroxypterosin Q (2), were isolated from the whole plants of Pteris ensiformis, together with six known compounds. The structures of 1 and 2 were determined through extensive 1D/2D-NMR and MS analyses. Compound 2 exhibited antitubercular activity (MIC 6.25 µg/ml) against Mycobacterium tuberculosis H37 Rv in vitro.


Assuntos
Antituberculosos , Indanos/química , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais , Pteris/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Antituberculosos/química , Antituberculosos/isolamento & purificação , Antituberculosos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pteris/metabolismo , Sesquiterpenos/isolamento & purificação
7.
Int J Mol Sci ; 14(7): 13063-77, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23799360

RESUMO

Four new labdane-type diterpenoids: hedychicoronarin (1), peroxycoronarin D (2), 7ß-hydroxycalcaratarin A (3), and (E)-7ß-hydroxy-6-oxo-labda-8(17),12-diene-15,16-dial (4), have been isolated from the rhizomes of Hedychium coronarium, together with 13 known compounds (5-17). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 3, 5, 6, and 10 exhibited inhibition (IC50 values ≤4.52 µg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 3-6, 10, and 11 inhibited fMLP/CB-induced elastase release with IC50 values ≤6.17 µg/mL.


Assuntos
Diterpenos , Superóxidos , Anti-Inflamatórios/farmacologia , Diterpenos/química , Humanos , Neutrófilos/efeitos dos fármacos , Elastase Pancreática , Superóxidos/antagonistas & inibidores , Zingiberaceae
8.
Environ Sci Pollut Res Int ; 29(57): 85669-85675, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34669130

RESUMO

This study aimed to investigate the impact of weather conditions on the daily incidence of the COVID-19 pandemic in late spring 2021 in Taiwan, which is unlike the weather conditions of the COVID-19 outbreak in 2020. Meteorological parameters such as maximum daily temperature, relative humidity, and wind speed were included. The Spearman rank correlation test was used to evaluate the relationship between weather and daily domestic COVID-19 cases. The maximum daily temperature had a positively significant correlation with daily new COVID-19 cases within a 14-day lag period, while the relative humidity and wind speed has a fairly high correlation with the number of daily cases within a 13- and 14-day lag, respectively. In addition, the weather characteristics during this period were an increasingly high temperature, with steady high relative humidity and slightly decreasing wind speed. Our study revealed the weather conditions at the time of the domestic outbreak of COVID-19 in Taiwan in May 2021 and the possible association between weather factors and the COVID-19 pandemic. Further large-scale analysis of weather factors is essential for understanding the impact of weather on the spread of infectious diseases.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Taiwan/epidemiologia , Tempo (Meteorologia) , Umidade , Temperatura
9.
J Nat Prod ; 74(5): 1021-7, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21391659

RESUMO

Five new compounds, 9-O-angeloyl-8,10-dehydrothymol (1), 9-(3-methylbutanoyl)-8,10-dehydrothymol (2), eupatobenzofuran (3), 2-hydroxy-2,6-dimethylbenzofuran-3(2H)-one (4), and 1-(2-hydroxy-4-methylphenyl)propan-1,2-dione (5), have been isolated from the aerial part of Eupatorium cannabinum subsp. asiaticum, together with 16 known compounds (6-21). Compounds 6-8, 11, 13, and 15 exhibited inhibition (IC50 values≤18.4 µM) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 2, 3, 10, 13, and 15 inhibited fMLP/CB-induced elastase release with IC50 values≤18.3 µM.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Benzofuranos/isolamento & purificação , Benzofuranos/farmacologia , Eupatorium/química , Fenilpropionatos/isolamento & purificação , Fenilpropionatos/farmacologia , Timol/isolamento & purificação , Timol/farmacologia , Adulto , Anti-Inflamatórios/química , Benzofuranos/química , Humanos , Concentração Inibidora 50 , Estrutura Molecular , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Neutrófilos/enzimologia , Elastase Pancreática/antagonistas & inibidores , Fenilpropionatos/química , Superóxidos/antagonistas & inibidores , Taiwan , Timol/análogos & derivados , Timol/química
10.
Bioorg Med Chem ; 16(16): 7639-45, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18662883

RESUMO

Certain amide-containing flavone and isoflavone derivatives were synthesized and evaluated for their antiproliferative activities. These compounds were synthesized via alkylation of hydroxyl precursors followed by the reaction with H(2)SO(4) and NaN(3) (Schmidt reaction). The preliminary assays indicated that the inhibitory activity against the growth of NCI-H661 decreased in an order of linked chromophore flavone-6-yl 16a-d>flavone-7-yl 17a-d>flavone-3-yl 15a-d and isoflavone-7-yl 18a-d. Among these flavone-6-yl derivatives, N-(4-methoxyphenyl)-2-(4-oxo-2-phenyl-4H-chromen-6-yloxy)acetamide (16c) was the most potent with a GI(50) value of 0.84 microM. The inhibitory activity against the growth of NPC-TW01 decreased in an order of linked chromophore flavone-6-yl 16a-d>isoflavone-7-yl 18a-d>flavone-7-yl 17a-d>flavone-3-yl 15a-d. Flavone-6-yl derivatives 16a-d demonstrated significant inhibitory activities against the growth of NPC-TW01 cell with an average GI(50) value of 0.84 microM. The oxime derivatives 1 and 2 caused accumulation of NPC-TW01 cell in G(2)/M phase which were distinct from that of their amide isomers 16b and 16c, respectively, which induced cell-cycle arrest in G(0)/G(1) phase followed by apoptosis. Therefore, the antiproliferative mechanism of flavone derivatives was affected not only by the phenyl benzopyran-4-one pharmacophore but also by the peripheral substituents.


Assuntos
Amidas/síntese química , Amidas/farmacologia , Isoflavonas/síntese química , Isoflavonas/farmacologia , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade
11.
J Nat Prod ; 71(10): 1692-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18817445

RESUMO

Six new phthalides, (S)-3-ethyl-7-hydroxy-6-methoxyphthalide (1), (S)-3-ethyl-7-hydroxy-5,6-dimethoxyphthalide (2), (S)-3-ethyl-5,6,7-trimethoxyphthalide (3), (R)-3-ethyl-7-hydroxy-6-methoxyphthalide (4), (Z)-3-ethylidene-7-hydroxy-6-methoxyphthalide (5), and (Z)-3-ethylidene-6,7-dimethoxyphthalide (6), have been isolated from the root of Pittosporum illicioides var. illicioides, together with seven known compounds. The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 1-4 exhibited inhibition (IC50

Assuntos
Benzofuranos/isolamento & purificação , Benzofuranos/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/enzimologia , Plantas Medicinais/química , Rosales/química , Rotenona/análogos & derivados , Superóxidos/metabolismo , Benzofuranos/química , Citocalasina B/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Ressonância Magnética Nuclear Biomolecular , Elastase Pancreática/efeitos dos fármacos , Elastase Pancreática/metabolismo , Raízes de Plantas/química , Rotenona/química , Rotenona/isolamento & purificação , Rotenona/farmacologia , Taiwan
12.
Chem Biodivers ; 5(7): 1345-52, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18649301

RESUMO

A new indole alkaloid, 11,12-dimethoxyhenningsamine, was isolated from the roots of Strychnos cathayensis, together with 19 known compounds. The structure of this new compound was determined through spectroscopic and mass-spectrometric analyses. Among the isolated compounds, 11-methoxyhenningsamine and aesculetin dimethyl ether exhibited potent inhibition (IC(50) < 5.5 microg/ml) on superoxide-anion generation and elastase release by human neutrophils in response to fMet-Leu-Phe/cytochalasin B.


Assuntos
Alcaloides Indólicos/isolamento & purificação , Strychnos/química , Anti-Inflamatórios/farmacologia , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Superóxidos/metabolismo
13.
Eur J Med Chem ; 40(9): 928-34, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15913847

RESUMO

Certain linear 4-anilinofuro[2,3-b]quinoline and angular 4-anilinofuro[3,2-c]quinoline derivatives were synthesized and evaluated in vitro against the full panel of NCI's 60 cancer cell lines. For the linear 4-anilinofuro[2,3-b]quinoline derivatives, 1-[4-(furo[2,3-b]quinolin-4-ylamino)phenyl]ethanone (5a) is the most cytotoxic with a mean GI50 value of 0.025 microM. Substitution at either furo[2,3-b]quinoline ring (2a, 2b, and 5b) or 4-anilino moiety (3-7) led to a decrease of cytotoxicity. For the angular 4-anilinofuro[3,2-c]quinoline derivatives, (E)-1-[3-(furo[3,2-c]quinolin-4-ylamino)phenyl]ethanone oxime (14a) exhibited potent inhibitory activities on UO-31, UACC-257, and UACC-62, with GI50 values of 0.03,<0.01, and<0.01 microM respectively. The same cytotoxicity profile was observed for its methyl counterpart, 14b, in which the GI50 values against UO-31, UACC-257, and UACC-62 was<0.01, 0.04 and<0.01 microM respectively. These results deserve full attention especially because 14a and 14b are relatively non-cytotoxic with the mean GI50 value of 7.73 and 8.91 microM respectively.


Assuntos
Antineoplásicos/farmacologia , Quinolinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Quinolinas/síntese química , Quinolinas/química
14.
Chem Biodivers ; 2(2): 253-63, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17191978

RESUMO

A series of oxime- and methyloxime-containing flavone, isoflavone, and xanthone derivatives (1-12) were synthesized (Scheme) and evaluated for their cytotoxic (Table 1) and antiplatelet activities (Table 2). The in vitro anticancer assay indicated that the cytotoxicity of structurally related compounds decreases in the order isoflavones (7a-7c) > flavones (8a-8c) > xanthones (9a-9c), electron-releasing substituents (R) on the Ph ring being favorable (mean GI50 values of 2.84, 12.3, and 20.9 microM for 7c, 8c, and 9c, resp.). The inhibition of platelet aggregation induced by arachidonic acid (AA) similarly decreased from the isoflavone 1 (IC50 = 2.97 microM) to the flavone 2 (7.70 microM) to the xanthone 3 (inactive). Thereby, compound 1 seems to be a promising lead, since it was not only the most-potent aggregation inhibitor (IC50 = 2.97 microM), but was also found to be noncytotoxic at a concentration of 100 microM.


Assuntos
Antineoplásicos/síntese química , Flavonas/síntese química , Isoflavonas/síntese química , Inibidores da Agregação Plaquetária/síntese química , Xantonas/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Flavonas/farmacologia , Humanos , Isoflavonas/farmacologia , Estrutura Molecular , Inibidores da Agregação Plaquetária/farmacologia , Xantonas/farmacologia
15.
Chem Biodivers ; 2(2): 205-14, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17191973

RESUMO

Certain 4-(phenylamino)furo[2,3-b]quinoline and 2-(furan-2-yl)-4-(phenylamino)quinoline derivatives were synthesized and evaluated in vitro against the full panel of NCIs 60 cancer cell lines. The preliminary results indicated these tricyclic 4-(phenylamino)furo[2,3-b]quinolines were more cytotoxic than their corresponding 2-(furan-2-yl)-4-(phenylamino)quinoline isomers. For the 4-(phenylamino)furo[2,3-b]quinolines, compounds 2a and 3d are two of the most potent with a mean GI50 value of 0.025 microM in each case. Inactivity of 2b and 2c (positional isomers of 2a) indicated that both electronic environment, and the distance between intercalating pharmacophore and H-bond-donating MeO group are important. For the 2-(furan-2-yl)-4-(phenylamino)quinoline isomers, compound 12 (a mean GI50 of 4.36 microM), which bears a para-COMe substituent, is more active than its meta-substituted counterpart 13 (10.5 microM). However, the electron-donating MeO substituent is preferred at the meta-position, and the cytotoxicity for the meta-substituted derivatives decreased in the order: MeO derivative 14b (3.05 microM) > oxime 16 (6.85 microM) > ketone 13 (10.5 microM) > methyl oxime 18 (20.6 microM).


Assuntos
Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Furanos/síntese química , Furanos/farmacologia , Quinolinas/síntese química , Quinolinas/farmacologia , Linhagem Celular Tumoral , Humanos , Estrutura Molecular
16.
Br J Pharmacol ; 172(19): 4671-83, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26102991

RESUMO

BACKGROUND AND PURPOSE: Dynamic polymerization of microtubules is essential for cancer cell growth and metastasis, and microtubule-disrupting agents have become the most successful anti-cancer agents in clinical use. Besides their antioxidant properties, flavonoids also exhibit strong microtubule-disrupting activity and inhibit tumour growth. We have designed, synthesized and tested a series of oxime/amide-containing flavone derivatives. Here we report the evaluation of one compound, WTC-01 for its anti-proliferative effects in human cancer cells. EXPERIMENTAL APPROACH: We used a range of cancer cell lines including two human nasopharyngeal carcinoma (NPC) cell lines, measuring proliferation, cell cycle and apoptosis, along with caspase levels and mitochondrial membrane potentials. Assays of tubulin polymerisation in vitro and computer modelling of the colchicine binding site in tubulin were also used. In mice, pharmacokinetics and growth of NPC-derived tumours were studied. KEY RESULTS: WTC-01 was most potent against proliferation of NPC cells (IC50 = 0.45 µM), inducing accumulation of cells in G2 /M and increasing apoptosis, time- and concentration-dependently. The colchicine competition-binding experiments and computer modelling results suggested that WTC-01 causes microtubule disruption via binding to the colchicine-binding site of tubulin resulting in mitochondrial membrane damage and cell apoptosis via activation of caspase-9/-3 without noticeable activation of the caspase-8. Notably, our in vivo studies demonstrated that at doses of 25 and 50 mg·kg(-1) , WTC-01 exhibited good pharmacokinetic properties and completely inhibited the growth of NPC-TW01 cells in a xenograft nude mouse model. CONCLUSIONS AND IMPLICATIONS: WTC-01, a new synthetic oxime-containing flavone, exhibited potent anti-tumour activity against NPC cells and merits further investigation.


Assuntos
Antineoplásicos/farmacologia , Cromonas/farmacologia , Oximas/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flavonas/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas
17.
Eur J Med Chem ; 106: 60-74, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26519930

RESUMO

We have designed and synthesized certain novel oxime- and amide-bearing coumarin derivatives as nuclear factor erythroid 2 p45-related factor 2 (Nrf2) activators. The potency of these compounds was measured by antioxidant responsive element (ARE)-driven luciferase activity, level of Nrf2-related cytoprotective genes and proteins, and antioxidant activity. Among them, (Z)-3-(2-(hydroxyimino)-2-phenylethoxy)-2H-chromen-2-one (17a) was the most active, and more potent than the positive t-BHQ in the induction of ARE-driven luciferase activity. Exposure of HSC-3 cells to various concentrations of 17a strongly increased Nrf2 nuclear translocation and the expression level of Nrf2-mediated cytoprotective proteins in a concentration-dependent manner. HSC-3 cells pretreated with 17a significantly reduced t-BOOH-induced oxidative stress. In the animal experiment, Nrf2-mediated cytoprotective proteins, such as aldo-keto reductase 1 subunit C-1 (AKR1C1), glutathione reductase (GR), and heme oxygenase (HO-1), were obviously elevated in the liver of 17a-treated mice than that of control. These results suggested that novel oxime-bearing coumarin 17a is able to activate Nrf2/ARE pathway in vivo and are therefore seen as a promising candidate for further investigation.


Assuntos
Elementos de Resposta Antioxidante/genética , Cumarínicos/química , Cumarínicos/farmacologia , Modelos Animais , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/metabolismo , Oximas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Luciferases/biossíntese , Luciferases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Oximas/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
Spat Spatiotemporal Epidemiol ; 5: 39-50, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23725886

RESUMO

Spatial data often possess multiple components, such as local clusters and global clustering, and these effects are not easy to be separated. In this study, we propose an approach to deal with the cases where both global clustering and local clusters exist simultaneously. The proposed method is a two-stage approach, estimating the autocorrelation by an EM algorithm and detecting the clusters by a generalized least square method. It reduces the influence of global dependence on detecting local clusters and has lower false alarms. Simulations and the sudden infant disease syndrome data of North Carolina are used to illustrate the difference between the proposed method and the spatial scan statistic.


Assuntos
Análise por Conglomerados , Morte Súbita do Lactente/epidemiologia , Algoritmos , Simulação por Computador , Humanos , Lactente , Análise dos Mínimos Quadrados , Modelos Estatísticos , Método de Monte Carlo , North Carolina/epidemiologia , Análise Espacial
19.
Eur J Med Chem ; 59: 227-34, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229058

RESUMO

Certain N-(naphthalen-2-yl)acetamide and N-(substituted phenyl)acetamide bearing quinolin-2(1H)-one and 3,4-dihydroquinolin-2(1H)-one derivatives have been synthesized and evaluated in vitro for their antiproliferative activities against a panel of human cancer cell lines including nasopharyngeal (NPC-TW01), lung carcinoma (H661), hepatoma (Hep3B), renal carcinoma (A498), and gastric cancer (MKN45). Among them, N-(naphthalen-2-yl)-2-(2-oxo-1,2,3,4-tetrahydroquinolin-6-yloxy)acetamide (18) was the most active against NPC-TW01 with an IC(50) value of 0.6 µM. Studies on NPC-TW01 cell cycle distribution revealed that compound 18 inhibited proliferation of NPC-TW01 by the alteration of cell division, accumulation of cells in S phase in a time- and concentration-dependent manners. In addition, compound 18 demonstrated very specific cytotoxicity against human nasopharyngeal carcinoma (NPC-TW01) cell lines with no detectable cytotoxicity against peripheral blood mononuclear cells (PBMCs) at a concentration of up to 50 µM.


Assuntos
Acetamidas/síntese química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Acetamidas/química , Acetamidas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Estrutura Molecular , Naftalenos/síntese química , Naftalenos/química , Naftalenos/farmacologia , Quinolonas/síntese química , Quinolonas/química , Quinolonas/farmacologia , Fase S/efeitos dos fármacos
20.
Bioorg Med Chem ; 15(20): 6527-34, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17689252

RESUMO

Certain oxime- and amide-containing quinolin-2(1H)-one derivatives were synthesized and evaluated for their antiproliferative and antiplatelet activities. These compounds were synthesized via alkylation of hydroxyl precursors followed by the reaction with NH(2)OH or NaN(3) (Schmidt reaction). The preliminary assays indicated that amide derivatives are either weakly active or inactive while the oxime counterparts exhibited potent inhibitory activities against platelet aggregation induced by collagen, AA (arachidonic acid), and U46619 (the stable thromboxan A(2) receptor agonist). Among them, (Z)-6-[2-(4-methoxyphenyl)-2-hydroxyiminoethoxy]quinolin-2(1H)-one (7c) was the most active against AA induced platelet aggregation with an IC(50) of 0.58microM and was inactive against cell proliferation. For the inhibition of U46619 induced aggregation, 7a and 8a-c exhibited very potent activities with IC(50) values in a range between 0.54 and 0.74microM. For the antiproliferative evaluation, N-(biphenyl-4-yl)-2-(2-oxo-1,2-dihydroquinolin-7-yloxy)acetamide (11d) was the most potent with GI(50) values of <10, 10.8, and <10microM against the growth of MT-2, NCI-H661, and NPC-Tw01, respectively, and possessed only a weak antiplatelet activity. Further evaluation of 11d as a potential anticancer agent is on-going.


Assuntos
Amidas/química , Oximas/química , Agregação Plaquetária/efeitos dos fármacos , Quinolinas/química , Quinolinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Quinolinas/síntese química , Relação Estrutura-Atividade
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