RESUMO
Histamine causes allergic reactions and can serve as an indicator for assessing food quality. This study designed and developed a dispersive micro solid-phase extraction (D-µSPE) method that combined the advantages of dispersive liquid-liquid extraction and solid-phase extraction (SPE). Molecularly imprinted polymers (MIPs) were employed as the solid phase in the D-µSPE method to extract histamine in wine samples. We used microwave energy to significantly reduce the synthesis time, achieving an 11.1-fold shorter synthesis time compared to the conventional MIP synthetic method. Under optimized D-µSPE conditions, our results showed that the dispersive solvent could effectively increase the adsorption performance of MIPs in wine samples by 97.7%. To improve the sensitivity of histamine detection in gas chromatography-mass spectrometry, we employed the microwave-assisted tandem derivatization method to reuse excess derivatization reagents and reduce energy consumption and reaction time. Calibration curves were constructed for wine samples spiked with 0-400 nmol histamine using the standard addition method, resulting in good linearity with a coefficient of determination of 0.999. The intra- and inter-batch relative standard deviations of the slope and intercept were < 0.7% and < 5.3%, respectively. The limits of quantitation and detection were 0.4 nmol and 0.1 nmol, respectively. The developed method was successfully applied to analyze the histamine concentration in 10 commercial wine samples. In addition, the AGREEprep tool was used to evaluate the greenness performance of the developed method, which obtained a higher score than the other reported methods.
Assuntos
Impressão Molecular , Vinho , Vinho/análise , Cromatografia Líquida de Alta Pressão/métodos , Histamina/análise , Polímeros/química , Extração em Fase Sólida/métodos , Impressão Molecular/métodosRESUMO
Tryptanthrin, an alkaloid applied in traditional Chinese medicine, exhibits a variety of pharmacological activities. This study aimed to investigate the anti-tumor activity of the tryptanthrin derivative (8-cyanoindolo[2,1-b]quinazoline-6,12-dione [CIQ]) in breast cancer cells. In both MDA-MB-231 and MCF-7 breast cancer cells, CIQ inhibited cell viability and promoted caspase-dependent apoptosis. At the concentration- and time-dependent ways, CIQ increased the levels of p-ERK, p-JNK, and p-p38 in breast cancer cells. We found that exposure to the JNK inhibitor or the ERK inhibitor partially reversed CIQ's viability. We also observed that CIQ increased reactive oxygen species (ROS) generation, and upregulated the phosphorylation and expression of H2AX. However, the pretreatment of the antioxidants did not protect the cells against CIQ's effects on cell viability and apoptosis, which suggested that ROS does not play a major role in the mechanism of action of CIQ. In addition, CIQ inhibited the invasion of MDA-MB-231 cells and decreased the expression of the prometastatic factors (MMP-2 and Snail). These findings demonstrated that the possibility of this compound to show promise in playing an important role against breast cancer.
Assuntos
Antineoplásicos , Apoptose , Neoplasias da Mama , Sobrevivência Celular , Quinazolinas , Feminino , Humanos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7 , Quinazolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
According to the alarming statistical analysis of global cancer, there are over 19 million new diagnoses and more than 10 million deaths each year. One such cancer is the oral squamous cell carcinoma (OSCC), which requires new therapeutic strategies. Ficus septica extract has been used in traditional medicine to treat infectious diseases. In this study, we examined the anti-proliferative effects of an extract of F. septica bark (FSB) in OSCC cells. Our results showed that FSB caused a concentration-dependent reduction in the viability of SCC2095 OSCC cells, as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, and was less sensitive to fibroblasts. In addition, FSB induced apoptosis by activating caspases, accompanied by the modulation of Akt/mTOR/NF-κB and mitogen-activated protein kinase signaling. Moreover, FSB increased reactive oxygen species generation in a concentration-dependent manner in SCC2095 cells. Furthermore, FSB inhibited cell migration and modulated the levels of the cell adhesion molecules including E-cadherin, N-cadherin, and Snail in SCC2095 cells. Pinoresinol, a lignan isolated from FSB, showed antitumor effects in SCC2095 cells, implying that this compound might play an important role in FSB-induced OSCC cell death. Taken together, FSB is a potential anti-tumor agent against OSCC cells.
Assuntos
Carcinoma de Células Escamosas , Ficus , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Bucais/patologia , Linhagem Celular Tumoral , Apoptose , Proliferação de CélulasRESUMO
Oral squamous cell carcinoma (OSCC) represents a clinical challenge due to the lack of effective therapy to improve prognosis. Hippo/Yes-associated protein (YAP) signaling has emerged as a promising therapeutic target for squamous cell carcinoma treatment. In this study, we investigated the antitumor activity and underlying mechanisms of {[N-(4-(5-(3-(3-(4-acetamido-3-(trifluoromethyl)phenyl)ureido)phenyl)-1,2,4-oxadiazol-3-yl)-3-chlorophenyl)-nicotinamide]} (ATN), a novel YAP inhibitor, in OSCC cells. ATN exhibited differential antiproliferative efficacy against OSCC cells (IC50 as low as 0.29 µM) versus nontumorigenic human fibroblast cells (IC50 = 1.9 µM). Moreover, ATN effectively suppressed the expression of YAP and YAP-related or downstream targets, including Akt, p-AMPK, c-Myc, and cyclin D1, which paralleled the antiproliferative efficacy of ATN. Supporting the roles of YAP in regulating cancer cell survival and migration, ATN not only induced caspase-dependent apoptosis, but also suppressed migration activity in OSCC. Mechanistically, the antitumor activity of ATN in OSCC was attributed, in part, to its ability to regulate Mcl-1 expression. Together, these findings suggest a translational potential of YAP inhibitors, represented by ATN as anticancer therapy for OSCC.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Apoptose , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteínas de Sinalização YAPRESUMO
Fructose overconsumption promotes tumor progression. Neuroblastoma is a common extracranial tumor with about 50% 5-year survival rate in high-risk children. The anti-tumor effect of Tribulus terrestris might bring new hope to neuroblastoma therapy. However, whether fructose disturbs the therapeutic effect of T. terrestris is currently unknown. In this study, the mouse neuroblastoma cell line, Neuro 2a (N2a) cells, was used to investigate the therapeutic effects of T. terrestris extract at various dosages (0.01, 1, 100 ng/ml) in regular EMEM medium or extra added fructose (20 mM) for 24 h. 100 ng/ml T. terrestris treatment significantly reduced the cell viability, whereas the cell viabilities were enhanced at the dosages of 0.01 or 1 ng/ml T. terrestris in the fructose milieu instead. The inhibition effect of T. terrestris on N2a migration was blunted in the fructose milieu. Moreover, T. terrestris effectively suppressed mitochondrial functions, including oxygen consumption rates, the activities of electron transport enzymes, the expressions of mitochondrial respiratory enzymes, and mitochondrial membrane potential. These suppressions were reversed in the fructose group. In addition, the T. terrestris-suppressed mitofusin and the T. terrestris-enhance mitochondrial fission 1 protein were maintained at basal levels in the fructose milieu. Together, these results demonstrated that T. terrestris extract effectively suppressed the survival and migration of neuroblastoma via inhibiting mitochondrial oxidative phosphorylation and disturbing mitochondrial dynamics. Whereas, the fructose milieu blunted the therapeutic effect of T. terrestris, particularly, when the dosage is reduced.
Assuntos
Frutose , Neuroblastoma , Animais , Linhagem Celular , Frutose/farmacologia , Camundongos , Mitocôndrias , Neuroblastoma/tratamento farmacológico , Extratos Vegetais/farmacologia , TribulusRESUMO
Excess synaptic glutamate release has pathological consequences, and the inhibition of glutamate release is crucial for neuroprotection. Kaempferol 3-rhamnoside (KR) is a flavonoid isolated from Schima superba with neuroprotective properties, and its effecton the release of glutamate from rat cerebrocortical nerve terminals was investigated. KR produced a concentration-dependent inhibition of 4-aminopyridine (4-AP)-evoked glutamate release with half-maximal inhibitory concentration value of 17 µM. The inhibition of glutamate release by KR was completely abolished by the omission of external Ca2+ or the depletion of glutamate in synaptic vesicles, and it was unaffected by blocking carrier-mediated release. In addition, KR reduced the 4-AP-evoked increase in Ca2+ concentration, while it did not affect 4-AP-evoked membrane potential depolarization. The application of selective antagonists of voltage-dependent Ca2+ channels revealed that the KR-mediated inhibition of glutamate release involved the suppression of P/Q-type Ca2+ channel activity. Furthermore, the inhibition of release was abolished by the calmodulin antagonist, W7, and Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN62, but not by the protein kinase A (PKA) inhibitor, H89, or the protein kinase C (PKC) inhibitor, GF109203X. We also found that KR reduced the 4-AP-induced increase in phosphorylation of CaMKII and its substrate synapsin I. Thus, the effect of KR on evoked glutamate release is likely linked to a decrease in P/Q-type Ca2+ channel activity, as well as to the consequent reduction in the CaMKII/synapsin I pathway.
Assuntos
Canais de Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Córtex Cerebral/metabolismo , Ácido Glutâmico/metabolismo , Quempferóis/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Córtex Cerebral/citologia , Relação Dose-Resposta a Droga , Quempferóis/química , Potenciais da Membrana/efeitos dos fármacos , Estrutura Molecular , Fosforilação , Ratos , Transdução de Sinais/efeitos dos fármacos , Sinapsinas/metabolismoRESUMO
In this study, the anti-proliferative effect of ilimaquinone, a sesquiterpene derivative from the marine sponge, in breast cancer cells was investigated. Ilimaquinone inhibited the proliferation of MCF-7 and MDA-MB-231 breast cancer cells with IC50 values of 10.6 µM and 13.5 µM, respectively. Non-tumorigenic human breast epithelial cells were less sensitive to ilimaquinone than breast cancer cells. Flow cytometric and Western blot analysis showed that ilimaquinone induced S-phase arrest by modulating the expression of p-CDC-2 and p21. Ilimaquinone induces apoptosis, which is accompanied by multiple biological biomarkers, including the downregulation of Akt, ERK, and Bax, upregulation of p38, loss of mitochondrial membrane potential, increased reactive oxygen species generation, and induced autophagy. Collectively, these findings suggest that ilimaquinone causes cell cycle arrest as well as induces apoptosis and autophagy in breast cancer cells.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Poríferos/metabolismo , Quinonas/farmacologia , Sesquiterpenos/farmacologia , Animais , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quinonas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Sesquiterpenos/isolamento & purificação , Transdução de SinaisRESUMO
Secondary metabolites in marine organisms exhibit various pharmacological activities against diseases, such as cancer. In this study, the anti-proliferative effect of JBIR-100, a macrolide isolated from Streptomyces sp., was investigated in breast cancer cells. Cell growth was inhibited in response to JBIR-100 treatment concentration- and time-dependently in both MCF-7 and MDA-MB-231 breast cancer cells. JBIR-100 caused apoptosis, as verified by caspase activation and the cleavage of PARP. Western blotting revealed that JBIR-100 modulated the expression of Akt/NF-κB signaling components and Bcl-2 family members. Overexpression of Mcl-1 partially rescued MCF-7 cells from JBIR-100-induced cytotoxicity. In addition, transmission electron microscopy analyses, confocal analysis, and western blot assay indicated that JBIR-100 inhibited autophagy in MCF-7 cells. Exposure to the autophagy inhibitor did not synergize JBIR-100-induced apoptosis. In summary, our results suggested that JBIR-100 may be potentially used for breast cancer therapy.
Assuntos
Neoplasias da Mama , Streptomyces , Apoptose , Autofagia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Humanos , Células MCF-7 , Macrolídeos/farmacologiaRESUMO
Elevated autophagy is highly associated with cancer development and progression. Fruit extracts of several plants inhibit activity of autophagy-related protease ATG4B and autophagy activity in colorectal cancer cells. However, the effects of these plant extracts in oral cancer cells remain unclear. In this study, we found that the extracted Tribulus terrestris fruit (TT-(fr)) and Xanthium strumarium fruit had inhibitory effects on autophagy inhibition in both SAS and TW2.6 oral cancer cells. Moreover, the fruit extracts had differential effects on cell proliferation of oral cancer cells. In addition, the fruit extracts hampered cell migration and invasion of oral cancer cells, particularly in TT-(fr) extracts. Our results indicated that TT-(fr) extracts consistently inhibited autophagic flux, cell growth and metastatic characteristics of oral cancer cells, suggesting TT-(fr) might contain function ingredient to suppress oral cancer cells.
Assuntos
Neoplasias Bucais , Tribulus , Autofagia , Proliferação de Células , Frutas , Humanos , Neoplasias Bucais/tratamento farmacológico , Extratos Vegetais/farmacologiaRESUMO
Chemical investigation of the marine soft coral Sarcophyton tenuispiculatum resulted in the isolation of a 1,4-dihydrobenzoquinone, sarcotenuhydroquinone (1), three new cembranoids, sarcotenusenes AâC (2â4), and ten previously reported metabolites 5-14. The chemical structures of all isolated metabolites were determined by detailed spectroscopic analyses. In biological assays, anti-inflammatory, cytotoxic, and peroxisome proliferator-activated receptor γ (PPAR-γ) transcription factor assays of all compounds were performed. None of the isolated compounds were found to exhibit activity in the PPAR-γ transcription factor assay. The anti-inflammatory assays showed that (+)-7α,8ß-dihydroxydeepoxysarcophine (13) inhibited the production of IL-1ß to 56 ± 1% at a concentration of 30 µM in lipopolysaccharide (LPS)-stimulated J774A.1 macrophage cells. In addition, 1 and 2 were found to exhibit cytotoxicity towards a panel of cancer cell lines.
Assuntos
Antozoários/metabolismo , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Diterpenos/metabolismo , Hidroquinonas/metabolismo , Monoterpenos/metabolismo , Animais , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Células MCF-7 , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Relação Estrutura-AtividadeRESUMO
We recently isolated a cardiac glycoside (CG), αldiginoside, from an indigenous plant in Taiwan, which exhibits potent tumor-suppressive efficacy in oral squamous cell carcinoma (OSCC) cell lines (SCC2095 and SCC4, IC50 < 0.2 µM; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays). Here, we report that αldiginoside caused Sphase arrest and apoptosis, through the inhibition of a series of signaling pathways, including those mediated by cyclin E, phospho-CDC25C (p-CDC25C), and janus kinase/signal transducer and activator of transcription (JAK/STAT)3. αldiginoside induced apoptosis, as indicated by caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage. Equally important, αldiginoside reduced Mcl-1 expression through protein degradation, and overexpression of Mcl-1 partially protected SCC2095 cells from αldiginoside's cytotoxicity. Taken together, these data suggest the translational potential of αldiginoside to foster new therapeutic strategies for OSCC treatment.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Glicosídeos Cardíacos/farmacologia , Neoplasias Bucais/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteólise , Transdução de Sinais/efeitos dos fármacosRESUMO
This study explores the amounts of common chemical ultraviolet (UV) filters (i.e., avobenzone, bemotrizinol, ethylhexyl triazone, octocrylene, and octyl methoxycinnamate) in cosmetics and the human stratum corneum. An ultrasound-vortex-assisted dispersive liquid-liquid microextraction (US-VA-DLLME) method with a high-performance liquid chromatography-diode array detector was used to analyze UV filters. A bio-derived solvent (i.e., anisole) was used as the extractant in the US-VA-DLLME procedure, along with methanol as the dispersant, a vortexing time of 4 min, and ultrasonication for 3 min. The mass-transfer rate of the extraction process was enhanced due to vortex-ultrasound combination. Various C18 end-capped columns were used to investigate the separation characteristics of the UV filters, with XBridge BEH or CORTECS selected as the separation column. Calibration curves were constructed in the 0.05-5 µg/mL (all filters except octocrylene) and 0.1-10 µg/mL (octocrylene) ranges, and excellent analytical linearities with coefficients of determination (r2) above 0.998. The developed method was successfully used to analyze sunscreen. Moreover, experiments were designed to simulate the sunscreen-usage habits of consumers, and the cup method was used to extract UV filters from the human stratum corneum. The results suggest that a makeup remover should be employed to remove water-in-oil sunscreens from skin.
Assuntos
Cosméticos , Epiderme/química , Microextração em Fase Líquida/métodos , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão , Humanos , SolventesRESUMO
Oral squamous cell carcinoma (OSCC) is the fifth common cause of cancer mortality in Taiwan with high incidence and recurrence and needs new therapeutic strategies. In this study, ursolic acid (UA), a triterpenoid, was examined the antitumor potency in OSCC cells. Our results showed that UA inhibited the proliferation of OSCC cells in a dose- and time-dependent manner in both Ca922 and SCC2095 oral cancer cells. UA induced caspase-dependent apoptosis accompanied with the modulation of various biological biomarkers including downregulating Akt/mTOR/NF-κB signaling, ERK, and p38. In addition, UA inhibited angiogenesis as evidenced by abrogation of migration/invasion and blocking MMP-2 secretion in Ca922 cells. Interestingly, UA induced autophagy in OSCC cells, as manifested by LC3B-II conversion and increased p62 expression and accumulation of autophagosomes. Inhibition by autophagy inhibitor enhanced UA-mediated apoptosis in Ca922 cells. The experiment provides a rationale for using triterpenoid in the treatment of OSCC.
Assuntos
Inibidores da Angiogênese/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Triterpenos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Humanos , Neoplasias Bucais/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Ácido UrsólicoRESUMO
The peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that plays a key role in regulating cellular metabolism, and is a therapeutic target for cancer therapy. To search for potential PPARγ activators, a compound library comprising 11 marine compounds was examined. Among them, a sterol, 3ß,11-dihydroxy-9,11-secogorgost-5-en-9-one (compound 1), showed the highest PPARγ activity with an IC50 value of 8.3 µM for inhibiting human breast adenocarcinoma cell (MCF-7) growth. Western blotting experiments showed that compound 1 induces caspase activation and PARP cleavage. In addition, compound 1 modulated the expression of various PPARγ-regulated downstream biomarkers including cyclin D1, cyclin-dependent kinase (CDK)6, B-cell lymphoma 2 (Bcl-2), p38, and extracellular-signal-regulated kinase (ERK). Moreover, compound 1 increased reactive oxygen species (ROS) generation, upregulated the phosphorylation and expression of H2AX, and induced autophagy. Interestingly, pre-treatment with the autophagy inhibitor 3-methyladenine rescued cells from compound 1-induced growth inhibition, which indicates that the cytotoxic effect of compound 1 is, in part, attributable to its ability to induce autophagy. In conclusion, these findings suggest the translational potential of compound 1 in breast cancer therapy.
Assuntos
Antozoários/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Esteróis/farmacologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Células MCF-7 , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Peroxisome proliferator-activated receptor γ (PPARγ), one of the transcription factors that regulate lipid metabolism and energy use in tumor cells, is a viable target for cancer therapy. In our search for potential PPARγ activator, extracts from five Formosan plants were tested. Among them, Momordica charantia L. showed the highest ability to activate PPARγ, which led us to identify its potential constituents. Among the seven compounds isolated from M. charantia, a triterpenoid, 5ß,19-epoxy-19-methoxycucurbita-6,23-dien-3ß,25-diol (compound 1), was identified as a PPARγ activator with an IC50 of 10 µM in breast cancer MCF-7 cells. Flow cytometric analysis indicated that compound 1 induced G1 cell cycle arrest which might be attributable to the modulation of phosphorylation and expression of numerous key signaling effectors, including cyclin D1, CDK6, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 1, leading to increased histone H3 acetylation. Taken together, these findings suggest that compound 1 may have therapeutic applications in cancer treatment through PPARγ activation. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Momordica charantia/química , PPAR gama/agonistas , Triterpenos/farmacologia , Pontos de Checagem do Ciclo Celular , Ciclina D1/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Regulação para Baixo , Humanos , Células MCF-7 , Estrutura Molecular , PPAR gama/metabolismo , Fosforilação , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismoRESUMO
Myoporum bontioides is a traditional medicinal plant in Asia with various biological activities, including anti-inflammatory and anti-bacterial characteristics. To identify the bioactive constituents from M. bontioides, a newly-identified flavone, 3,4'-dimethoxy-3',5,7-trihydroxyflavone (compound 1), along with eight known compounds, were investigated in human MCF-7 breast cancer, SCC4 oral cancer, and THP-1 monocytic leukemia cells. Among these compounds, compound 1 exhibited the strongest antiproliferative activity with half-maximal inhibitory concentration (IC50) values ranging from 3.3 µM (MCF-7) to 8.6 µM (SCC4). Flow cytometric analysis indicated that compound 1 induced G2/M cell cycle arrest in MCF-7 cells. Mechanistic evidence suggests that the G2/M arrest could be attributable to compound 1's modulatory effects on the phosphorylation and expression of numerous key signaling effectors, including cell division cycle 2 (CDC2), CDC25C, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 2 (HDAC2) and HDAC4, leading to increased histone H3 acetylation and p21 upregulation. Together, these findings suggest the translational potential of compound 1 as a breast cancer treatment.
Assuntos
Neoplasias da Mama/metabolismo , Flavonas/farmacologia , Pontos de Checagem da Fase M do Ciclo Celular , Myoporum/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Flavonas/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacosRESUMO
T315, an integrin-linked kinase (ILK) inhibitor, has been shown to suppress the proliferation of breast cancer, stomach cancer and chronic lymphocytic leukemia cells. Here we demonstrate that T315 decreases cell viability of acute myeloid leukemia (AML) cell lines (HL-60 and THP-1) and primary leukemia cells from AML patients in a dose-responsive manner. Normal human bone marrow cells are less sensitive than leukemia cells to T315. T315 down regulates protein kinase B (Akt) and p-Akt and induces caspase activation, poly-ADP-ribose polymerase (PARP) cleavage, apoptosis and autophagy through an ILK-independent manner. Interestingly, pretreatment with autophagy inhibitors rescues cells from apoptosis and concomitant PARP cleavage, which implicates a key role of autophagic cell death in T315-mediated cytotoxicity. T315 also demonstrates efficacy in vivo, suppressing the growth of THP-1 xenograft tumors in athymic nude mice when administered intraperitoneally. This study shows that autophagic cell death and apoptosis cooperatively contribute to the anticancer activity of T315 in AML cells. In conclusion, the complementary roles of apoptotic and autophagic cell death should be considered in the future assessment of the translational value of T315 in AML therapy.
Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Leucemia Mieloide Aguda/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Células HL-60 , Humanos , Masculino , Camundongos , Camundongos Nus , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
DNA methylation plays a pivotal role in the epigenetic regulation of the transcription of a number of cancer-related genes, thereby representing an important target for cancer prevention and treatment. In our search for DNA methyltransferase (DNMT) inhibitors from Formosan plants, by screening against a library consisting of 12 structurally distinct natural products, we identified kazinol Q {4-[6-(1,1-dimethyl-allyl)-7-hydroxy-chroman-2-yl]-3,6-bis-(3-methyl-but-2-enyl)-benzene-1,2-diol} as an inhibitor of recombinant DNMT1 with IC50 of 7 µM. The effect of kazinol Q on DNMT inhibition was validated by its ability to reactivate the expression of a DNA methylation-silenced gene, E-cadherin, in MDA-MB-231 breast cancer cells. Moreover, kazinol Q suppressed the proliferation of MCF-7 breast and LNCaP prostate cancer cells, in part, through apoptosis induction. The role of DNMT1 inhibition in mediating kazinol Q's antiproliferative effect was supported by the protective effect of ectopic expression of DNMT1 on kazinol Q-induced cell death. Molecular modeling analysis suggests that kazinol Q inhibited DNMT activity by competing with cytosine binding, a mechanism similar to that described for (-)-epigallocatechin-3-gallate (EGCG). Relative to EGCG, kazinol Q exhibits several desirable features for drug development, including chemical stability and increased hydrophobicity, and might have therapeutic relevance to cancer treatment.
Assuntos
DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Metilação de DNA/efeitos dos fármacos , Flavonoides/farmacologia , Hemiterpenos/farmacologia , Antígenos CD , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1 , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Feminino , Flavonoides/química , Hemiterpenos/química , Humanos , Concentração Inibidora 50 , Masculino , Simulação de Acoplamento Molecular , Neoplasias da Próstata/patologia , Espécies Reativas de Oxigênio/metabolismo , TaiwanRESUMO
Ten new lantabetulic acid (1) derivatives 2-11 were synthesized and their cytotoxicities against human prostate cancer cells were evaluated. PC3 cells treated with 10 µM 8 exhibited the most potent G1 phase arrest. In addition, 10 µM 8 markedly decreased the levels of cyclin E and cdk2 and caused an increase in the p21 and p27 levels, while 20 µM 8 mainly led to cell death through the apoptotic pathway, which correlated with an increase in reactive oxygen species levels, decreased expression levels of Bcl-2 and caspase-8, the induction of mitochondrial changes, and decreased levels of cytochrome c in mitochondria. The dual action of 8 could provide a new approach for the development of chemotherapeutic drugs.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Neoplasias da Próstata/patologia , Triterpenos/farmacologia , Antineoplásicos/síntese química , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estrutura Molecular , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Triterpenos/síntese químicaRESUMO
Distinct metabolic strategies used by cancer cells to gain growth advantages, such as shifting from oxidative phosphorylation to glycolysis, constitute a basis for their selective targeting as a novel approach for cancer therapy. Thiazolidinediones (TZDs) are ligands for the nuclear transcription factor peroxisome proliferator-activated receptor gamma (PPARγ) and they are clinically used as oral hypoglycemic agents. Accumulating evidence suggests that the ability of TZDs to suppress cancer cell proliferation through the interplay between apoptosis and autophagy was, at least in part, mediated through PPARγ-independent mechanisms. This review highlights recent advances in the pharmacological exploitation of the PPARγ-independent anticancer effects of TZDs to develop novel agents targeting tumor metabolism, including glucose transporter inhibitors and adenosine monophosphate-activated protein kinase, which have translational potential as cancer therapeutic agents.