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1.
Int J Nanomedicine ; 11: 4643-4656, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695323

RESUMO

Angiogenesis plays a critical role in the growth and metastasis of cancer, and growth factors released from cancer promote blood-vessel formation in the tumor microenvironment. The angiogenesis is accelerated via interactions of growth factors with the high-affinity receptors on cancer cells. In particular, heparan sulfate proteoglycans (HSPGs) on the surface of cancer cells have been shown to be important in many aspects of determining a tumor's phenotype and development. Specifically, the regulation of the interactions between HSPGs and growth factors results in changes in tumor progression. A peptide with heparin-binding (HBP) activity has been developed and synthesized to inhibit tumor growth via the prevention of angiogenesis. We hypothesized that HBP could inhibit the interaction of growth factors and HSPGs on the surface of cancer cells, decrease paracrine signaling in endothelial cells (ECs), and finally decrease angiogenesis in the tumor microenvironment. In this study, we found that HBP had antiangiogenic effects in vitro and in vivo. The conditioned media obtained from a breast cancer cell line treated with HBP were used to culture human umbilical vein ECs (HUVECs) to evaluate the antiangiogenic effect of HBP on ECs. HBP effectively inhibited the migration, invasion, and tube formation of HUVECs in vitro. In addition, the expressions of angiogenesis-mediating factors, including ERK, FAK, and Akt, were considerably decreased. HBP also decreased the levels of invasive factors, including MMP2 and MMP9, secreted by the HUVECs. We demonstrated significant suppression of tumor growth in a breast cancer xenograft model and enhanced distribution of HBP at the site of tumors. Taken together, our results show that HBP has antiangiogenic effects on ECs, and suggest that it may serve as a potential antitumor agent through control of the tumor microenvironment.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Proteína Morfogenética Óssea 4/uso terapêutico , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Peptídeos/uso terapêutico , Sequência de Aminoácidos , Inibidores da Angiogênese/farmacologia , Animais , Proteína Morfogenética Óssea 4/química , Proteína Morfogenética Óssea 4/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Heparina/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sus scrofa , Distribuição Tecidual/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Agric Food Chem ; 60(41): 10245-55, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23046062

RESUMO

Jujube (Ziziphus jujube) was analyzed at eight stages of ripeness (S1-8) for protein, by HPLC and mass spectroscopy for free amino acids and flavonoids, and by colorimetry for total flavonoids and antioxidative activity. The ripe fruit had lower levels of protein, flavonoids, and antioxidative activity than that of the unripe fruit. Free amino acids levels peaked at S5, due mainly to an increase in free asparagine. Extracts were also tested against four cell lines using the MTT cell viability assay. All growth stages dose-dependently inhibited HeLa cervical cancer cells, whereas the inhibition of Hel299 normal lung and A549 lung cancer cells decreased as the fruit matured and was well correlated with the flavonoid content and antioxidative activity. Chang normal liver cells were inhibited by only the S5 extract. U937 lymphoma cells were unaffected by the extracts. These results show the effect of fruit maturity on nutritional and health-promoting components.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Flavonoides/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Ziziphus/química , Aminoácidos/análise , Asparagina/análise , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Neoplasias Pulmonares , Extratos Vegetais/farmacologia , Proteínas de Plantas/análise , Células U937
3.
J Agric Food Chem ; 60(36): 9151-61, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22900641

RESUMO

We determined the phenolic, anthocyanin, and proanthocyanidin content of three brown, purple, and red rice brans isolated from different rice varieties using HPLC-PDA with the aid of 27 standards of known structure and matching unknown peaks to a spectral library of known compounds. Antioxidative capacities were determined by DPPH and ORAC and cell-inhibiting effects using an MTT assay. Based on the calculated IC(50) values, the light-brown bran had no effect, the purple bran exhibited a minor effect on leukemia and cervical cancer cells, and the red bran exhibited strong inhibitory effects on leukemia, cervical, and stomach cancer cells. High concentrations of protocatechuic acid and anthocyanins in purple bran and proanthocyanidins in red bran were identified. The red bran was further fractionated on a Sephadex column. Fraction 3 rich in proanthocyanidin oligomers and polymers had the greatest activity. Red bran has the potential to serve as a functional food supplement for human consumption.


Assuntos
Antioxidantes/farmacologia , Fibras na Dieta/farmacologia , Inibidores do Crescimento/farmacologia , Oryza/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Linhagem Celular Tumoral , Fibras na Dieta/análise , Inibidores do Crescimento/química , Humanos , Pigmentação , Extratos Vegetais/química
4.
J Agric Food Chem ; 60(15): 3891-9, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22482398

RESUMO

Partial acid hydrolysis of the tetrasaccharide (lycotetraose) side chain of the tomato glycoalkaloid α-tomatine resulted in the formation of four products with three, two, one, and zero carbohydrate side chains, which were separated by high-performance liquid chromatography (HPLC) and identified by thin-layer chromatography (TLC) and liquid chromatography ion-trap time-of-flight mass spectrometry (LCMS-IT-TOF). The inhibitory activities in terms of IC(50) values (concentration that inhibits 50% of the cells under the test conditions) of the parent compound and the hydrolysates, isolated by preparative HPLC, against normal human liver and lung cells and human breast, gastric, and prostate cancer cells indicate that (a) the removal of sugars significantly reduced the concentration-dependent cell-inhibiting effects of the test compounds, (b) PC3 prostate cancer cells were about 10 times more susceptible to inhibition by α-tomatine than the breast and gastric cancer cells or the normal cells, (c) the activity of α-tomatine against the prostate cancer cells was 200 times greater than that of the aglycone tomatidine, and (d) the activity increased as the number of sugars on the aglycone increased, but this was only statistically significant at p < 0.05 for the normal lung Hel299 cell line. The effect of the alkaloids on tumor necrosis factor α (TNF-α) was measured in RAW264.7 macrophage cells. There was a statistically significant negative correlation between the dosage of γ- and α-tomatine and the level of TNF-α. α-Tomatine was the most effective compound at reducing TNF-α. The dietary significance of the results and future research needs are discussed.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Tomatina/química , Tomatina/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Solanum lycopersicum/química , Masculino , Estrutura Molecular , Próstata , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/fisiopatologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/fisiopatologia , Tomatina/análogos & derivados
5.
J Agric Food Chem ; 59(24): 12801-14, 2011 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-22070764

RESUMO

Tomato (Solanum lycopersicum) plants synthesize nutrients, pigments, and bioactive compounds that benefit nutrition and human health. The nature and concentrations of these compounds are strongly influenced by varietal factors such as size and color as well as by processing. To better understand how these factors affect the concentration of nutrients and bioactive compounds, we analyzed 11 Korean tomato varieties grown under the same greenhouse conditions and 13 processed commercial tomato products for free amino acids and amino acid metabolites by HPLC, for individual phenolics by HPLC-MS, for total phenolics by the Folin-Ciocalteu method, for antioxidative activity by the FRAP and DPPH methods, and for cancer cell-inhibiting effects by the MTT assay. We also determined the protein content of the tomatoes by an automated Kjeldahl method. The results show that there is a broad range of bioactive compounds across tomato varieties and products. Small tomatoes had higher contents of bioactive compounds than the large ones. The content of phenolic compounds of processed products was lower than that of fresh tomatoes. Tomato extracts promoted growth in normal liver (Chang) cells, had little effect in normal lung (Hel299) cells, mildly inhibited growth of lung cancer (A549) cells, and first promoted and then, at higher concentrations, inhibited growth in lymphoma (U937) cells. The relationship of cell growth to measured constituents was not apparent. Dietary and health aspects of the results are discussed.


Assuntos
Aminoácidos/análise , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Fenóis/análise , Solanum lycopersicum/química , Agricultura/métodos , Linhagem Celular Tumoral , Análise de Alimentos/métodos , Manipulação de Alimentos , Frutas/química , Humanos , Coreia (Geográfico) , Extratos Vegetais/química , Extratos Vegetais/farmacologia
6.
J Agric Food Chem ; 58(13): 7547-56, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20560602

RESUMO

Tomato ( Solanum lycopersicum ) plants synthesize nutrients, pigments, and secondary metabolites that benefit nutrition and human health. The concentrations of these compounds are strongly influenced by the maturity of the tomato fruit on the vine. Widely consumed Korean tomatoes of the variety Doturakworld were analyzed for changes in the content of free amino acids, phenolic compounds, chlorophylls, carotenoids, and glycoalkaloids at 11 stages (S1-S11) of ripeness. The results show that (a) the total content (in mg/100 g of FW) of the free amino acids and other nitrogen-containing compounds in the extracts ranged from about 41 to 85 in the green tomato extracts S1-S7 and then increased to 251 (S9) in the red extracts, followed by a decrease to 124 in S11 red extracts; (b) the total initial concentration and composition of up to 12 phenolic compounds of approximately 2000 microg/100 g of FW varied throughout the ripening process, with the quantity decreasing and the number of individual compounds increasing in the red tomato; (c) chlorophyll a and b content of tomatoes harvested during S1 was 5.73 mg/100 g of fresh pericarp and then decreased continuously to 1.14 mg/100 g for S11; (d) the concentration (in mg/100 g of FW) of lycopene in the S8 red extract of 0.32 increased to 1.27 in S11; and (e) tomatoes harvested during S1 contained 48.2 mg of dehydrotomatine/100 g of FW, and this value continually decreased to 1.5 in S7, with no detectable levels in S8-S11. The corresponding alpha-tomatine content decreased from S1 (361) to S8 (13.8). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell assay IC(50) values showed that Hel299 lung cells, A549 lung cancer cells, and HeLa cervical carcinoma cells were highly susceptible to inactivation by glycoalkaloid-rich green tomato extracts. Chang normal liver cells and U937 lymphoma cells were less susceptible. The possible significance of the results for plant physiology and the diet is discussed.


Assuntos
Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Alcaloides/análise , Alcaloides/farmacologia , Aminoácidos/análise , Aminoácidos/farmacologia , Carotenoides/análise , Carotenoides/farmacologia , Proliferação de Células/efeitos dos fármacos , Clorofila/análise , Clorofila/farmacologia , Feminino , Humanos , Hidroxibenzoatos/análise , Hidroxibenzoatos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/fisiopatologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/fisiopatologia
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