295 resultados para antitumoral
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This paper describes a new method for the preparation of 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadien-3-one 1 and its derivatives 2-5. This set of synthetic compounds exhibited high antitumoral activities regarding in vitro screening against several human tumor cell lines as lung carcinoma NCI-460, melanoma UACC-62, breast MCF-7, colon HT-29, renal 786-O, ovarian OVCAR-03 and ovarian expressing the resistance phenotype for adriamycin NCI-ADR/ RES, prostate PC-3, and leukemia K-562. Compounds were also tested against murine tumor cell line B16F10 melanoma and lymphocytic leukemia L1210 as well as to their effect toward normal macrophages. Specific activity against colon cancer cells HT-29 was observed for all tested compounds and suggests further studies with models of colon cancer. Compounds 1, 2, and 4 showed significant cytotoxic activity with IC(50) values <= 2.3 mu M for all human cancer cell lines. Intraperitoneal acute administration of compound 1 and 2 showed very low toxicity rate. (C) 2010 Elsevier Ltd. All rights reserved.
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The alkaloid extract and five alkaloids isolated from subterranean stem bark of Duguetia furfuracea (Annonaceae) were investigated for the following activities: antitumoral, trypanocidal and leishmanicidal. Dicentrinone showed weak cytotoxicity, but it had the strongest leishmanicidal activity IC(50) 0.01 mu M). Duguetine and duguetine beta-N-oxide caused considerable antitumoral activity in every cell lines evaluated, although duguetine was more active against trypomastigote forms (IC(50) 9.32 mu M) than other alkaloids tested. (C) 2009 Elsevier GmbH. All rights reserved.
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A descoberta de novas drogas (produtos naturais e substâncias sintéticas) com atividade antineoplástica vem sendo dificultada devido ao teste de laboratório "in vitro". Optou-se, então por usar para triagem dessas drogas antitumorais a cultura de cálula humana neoplástica cultivada de modo contínuo: a linhagem de célula Hela derivada por Gey de uma carcinoma uterino humano. Foi utilizada uma cultura de célula estacionária, diluída 0-20 mcg/ml (conteúdo proteico celular, segundo técnica de Oyama e Eagle) em meio basal de Eagle com 10% de soro de vitelo, acrescido de penicilina 100 unidades/ml, estreptomicina 100 mcg/ml e fungizon 5 mcg/ml. A essa cultura adicionou-se o material a ser testado em doses compreendidas entre 0,001 mcg/ml a 100 mcg/ml. Após 72 horas, os resultados foram analisados para determinar-se a DI 50 (dose que inibe 50% do crescimento celular comparado ao controle). O numero de experimentos foram constantes para uma mesma droga. Foram testados 18 substâncias sintéticas e 16 produtos naturais. Consideraram-se ativas as amostras com DI 50≤40 mcg/ml para produtos naturais e com DI 50≤8 mcg/ml para substâncias sintéticas devido a menor sensibilidade da referida linhagem celular em relação a KB (derivada de carcinoma epidermóide de nasofaringe humana) cultura utilizada pelo National Cancer Institute (U.S.A) para objetivos similares ao proposto no presente trabalho.
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Background: We demonstrated that DC Bead (Biocompatibles UK, Ltd) could be loaded with sunitinib and injected intra-arterially in the rabbit without unexpected toxicity. The purpose of this study is to evaluate the antitumoral effect of sunitinib eluting beads in the VX2 tumor model of liver cancer. Methods: VX2 tumors were implanted in the left liver lobe of New-Zealand white rabbits. Animals were assigned to 3 groups: Group 1 (n=6) received 1.5mg of sunitinib loaded in 0.05ml of 100-300um DC Bead, group 2 (n=5) received 0.05ml of 100-300um DC Bead, group 3 (n=5) received 0.05ml NaCl 0.9% in the left hepatic artery. One animal in each group was sacrificed at 24 hours and the others were followed for survival until day 15. Liver enzymes were measured daily. In group 1, plasmatic sunitinib concentration were measured daily by LC MS/MS tandem mass spectroscopy. At day 15 all living animals were sacrificed. After sacrifice, the livers were harvested for determination of the VEGF receptor tyrosine kinase activity by western blot and histopathological examination. Results: In group 1, no animals died during follow-up. In group 2, 2 animals died during follow-up on day x. In control group 3, 3 animals died during follow up on day x. In group 1 plasmatic sunitinib levels remained under therapeutic concentration throughout the experiment. Very high concentrations of sunitinib were measured in the liver tissue 24 and 15 days after embolization. Inhibition of the phosphorylation of the RTK was demonstrated at 24h and 15 days in groups 1. Sunitinib eluting beads seemed to penetrate in the tumor more effectively and there was more necrosis around the beads than their bland counterparts. Conclusions: Administration of sunitinib eluting beads in VX2 carrying rabbits resulted invery high drug concentrations at the site of embolization with minimal systemic passage. Despite the very high tissular sunitinib concentration we did not observe any additional toxicity with loaded beads. Sunitinib eluting beads inhibit the activation of RTK's triggered by ischemia and seem to prolong survival of the treated animals. Therefore we consider that local treatment with sunitinib may provide a promising approach for the treatment of liver cancer.
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Oleanolic and ursolic acids are triterpenes that exist abundantly in the plant kingdom. They show antitumor activity and their cytotoxic activity was already evaluated against a broad range of cell lines. The inhibition of enzymes involved in the metabolism of DNA and the induction of apoptosis are known events that have been related to the antitumour activity of these triterpenes. The antiinflamatory and antioxidant activities also seem to play an important role in their antitumour activity. In this review, it is presented an overview of the importance of the potential antitumour, antiinflamatory and antioxidant activities of these triterpenoid derivatives. Also, we propose a structural-activity relationship to triterpenes containing oleanane or ursane skeleton and their cytotoxic activity.
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The cytotoxicity of the dichloromethane crude extract (DCE), obtained from the aerial parts of Pothomorphe umbellata (L.) Miq (Piperaceae), was evaluated against nine human cancer cell lines (MCF-7, NCI-ADR/RES, OVCAR-3, PC-3, HT-29, NCI-H460, 786-O, UACC-62, K-562). The DCE presented antiproliferative activity with good potency against all cell lines at low concentrations (between 4.0 and 9.5 µg/mL) and with selectivity (1.55 µg/mL) for the leukemia cell line (K-652). DCE (100, 200, 300 and 400 mg/kg, ip) was also evaluated in the Ehrlich ascites tumor model. Both the survival number and the life span of the animals that died increased by at least 45 and 50%, respectively (8 animals per group), demonstrating P. umbellata extract potential anticancer activity. The results of the in vivo antitumor activity prompted the fractionation of the crude extract. The crude extract was submitted to dry column chromatography with dichloromethane-methanol (99:1). The column effluent fractions were extracted with methanol, dried under vacuum yielding fractions FR1 (less polar), FR2 (medium polarity), and FR3 (polar), which were analyzed for their growth inhibition or cytotoxic properties by a 48-h sulforhodamine B cell viability assay by measuring the total protein content. FR1 demonstrated high potency and cytotoxicity, a result compatible with the high toxicity of oxalic acid; FR2, containing 4-nerolidylcathecol, presented the lowest cytotoxic activity compared to the other two fractions but with selectivity for prostate cancer cell line; FR3, containing a mixture of steroids described in the literature as possessing various biological activities, also presented potent anticancer in vitro activity. These results suggest that P. umbellata DCE in vivo antitumor activity may be a consequence of the activity of different active principles.
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Tesis (Maestría en Ciencias con Especialidad en Inmunobiología) UANL
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Tesis (Maestría en Ciencias con Especialidad en Inmunobiología) U.A.N.L.
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Tesis (Maestría en Ciencias con Orientación en Morfología) UANL, 2013.
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Tesis (Doctorado en Ciencias con Especialidad en Biología Molecular e Ingeniería Genética) UANL
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Tesis (Doctor en Ciencias con Orientación Terminal en Morfología) UANL, 2010.
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L'inhibidor de carboxipeptidasa de patata (PCI) és un antagonista de l'EGF. Un dels problemes del PCI, però, és la baixa afinitat per l'EGFR en comparació amb el lligand natural. En aquest treball s'han dissenyat nous bloquejadors de la via ErbB partint de l'estructura de l'EGF per tal d'augmentar l'afinitat d'unió. S'ha determinat que les variants tenen reduïda la capacitat d'activació del receptor però segueixen promovent la proliferació cel·lular. Tot i així, s'ha obtingut una variant, l'EGF Truncat, que tot i no estar correctament plegada, és la que ofereix uns millors. També s'ha dut a terme un tractament combinat entre el PCI i un inhibidor de tirosin quinases d'aquesta mateixa via, l'Iressa. Els resultats han posat de manifest que hi ha un antagonisme entre els dos tractaments. Aquesta és la primera vegada que s'associa de forma directa un tipus de tractament amb una resistència associada a l'activació de la producció autocrina de lligands, i representa un avenç molt important en la recerca oncològica.
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Influences on the use of chemotherapy for the treatment of cancer within the South East region of England for patients diagnosed with colorectal, lung, breast and prostate cancer were investigated. The variables investigated as possibly influencing the selection of chemotherapy were the sex of the patients, their age, the year of diagnosis, the cancer site, the cancer stage, the index of multiple deprivation (IMD) and the cancer network of residence. Logistic regression used to adjust the proportion receiving chemotherapy in relation to other variables considered showed significant differences in the proportion of patients receiving chemotherapy between different cancer sites and different networks. There was also a highly significant trend seen in use of chemotherapy over time; the adjusted proportion of patients receiving chemotherapy increasing from 10.6% in 1993 to 24.3% in 2002. Age, stage and cancer site seemed to have the most influence on the use of chemotherapy.
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The reaction of cis-[RuCl2(dppb)(N-N)], dppb = 1,4-bis(diphenylphosphino)butane, complexes with the ligand HSpymMe(2), 4,6-dimethyl-2-mercaptopyrimidine, yielded the cationic complexes [Ru(SpymMe(2))(dppb)(N-N)]PF6, N-N = bipy (1) and Me-bipy (2), bipy = 2,2`-bipyridine and Me-bipy = 4,4`dimethyl-2,2`-bipyridine, which were characterized by spectroscopic and electrochemical techniques and X-ray crystallography and elemental analysis. Additionally, preliminary in vitro tests for antimycobacterial activity against Mycobacterium tuberculosis H37Rv ATCC 27264 and antitumor activity against the MDA-MB-231 human breast tumor cell line were carried out on the new complexes and also on the precursors cis-[RuCl2(dppb)(N-N)], N-N = bipy (3) and Me-bipy (4) and the free ligands dppb, bipy, Me-bipy and SpymMe(2). The minimal inhibitory concentration (MIC) of compounds needed to kill 90% of mycobacterial cells and the IC50 values for the antitumor activity were determined. Compounds 1-4 exhibited good in vitro activity against M. tuberculosis, with MIC values ranging between 0.78 and 6.25 mu g/mL, compared to the free ligands (MIC of 25 to >50 mu g/mL) and the drugs used to treat tuberculosis. Complexes I and 2 also showed promising antitumor activity, with IC50 values of 0.46 +/- 0.02 and 0.43 +/- 0.08 mu M, respectively, against MDA-MB-231 breast tumor cells. (C) 2008 Elsevier Inc. All rights reserved.
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A new copper(II) complex of santonic acid [Cu(2)(sant)(4)(H(2)O)(2)]center dot 21/2H(2)O has been prepared and characterized by electronic, vibrational, EPR spectral studies, and stability determinations in solution. The presence of two antiferrromagnetically coupled copper centers in the solid state was detected by EPR. The dinuclear Cu(II) complex crystallizes in the tetragonal P4(3)2(1)2 space group, with a = b = 14.498(3), c = 64.07(1) angstrom. Biological studies indicate that the complex displays interesting potential antitumoral actions. (C) 2008 Elsevier Ltd. All rights reserved.