RESUMO
AIMS: This study reports the biological properties of LQFM030 in vivo, a molecular simplification of the compound nutlin-1. MAIN METHODS: Ehrlich ascites tumor (EAT)-bearing mice were treated intraperitoneally with LQFM030 (50, 75 or 150mg/kg) for 10days to determine changes in ascites tumor volume, body weight, cytotoxicity and angiogenesis. Moreover, flow cytometric expression of p53 and p21 proteins and caspase-3/7, -8 and -9 activation were investigated in EAT cells from mice treated. Acute oral systemic toxicity potential of LQFM030 in mice was also investigated using an alternative method. KEY FINDINGS: Treatment of EAT-bearing mice with LQFM030 resulted in a marked decline in tumor cell proliferation and the vascular endothelial growth factor (VEGF) levels along with enhanced survival of the mice. Apoptotic tumor cell death was detected through p53 and p21 modulation and increase of caspase-3/7, -8 and -9 activity. LQFM030 also showed orally well tolerated, being classified in the UN GHS category 5 (LD50>2000-5000mg/Kg). SIGNIFICANCE: LQFM030 seems to be a promising antitumor candidate for combinatory therapy with typical cytotoxic compounds, reducing the toxicity burden while allowing a superior anticancer activity. Moreover, these data also open new perspectives for LQFM030 as an antiangiogenic agent for treatment of diseases involving VEGF overexpression.
Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma de Ehrlich/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Piperidinas/farmacologia , Pirazóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Inibidores da Angiogênese/toxicidade , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Ehrlich/patologia , Caspases/biossíntese , Feminino , Injeções Intraperitoneais , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Proteína Oncogênica p21(ras)/biossíntese , Proteína Oncogênica p21(ras)/genética , Piperidinas/toxicidade , Pirazóis/toxicidade , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genéticaRESUMO
OBJECTIVE: The activation of the p53 pathway through the inhibition of MDM2 has been proposed as a novel therapeutic strategy against tumours. A series of cis-imidazoline analogues, termed nutlins, were reported to displace the recombinant p53 protein from its complex with MDM2 by binding to MDM2 in the p53 pocket, and exhibited an antitumour activity both in vitro and in vivo. Thus, the purpose of this study was to evaluate the antitumour properties of LQFM030 (2), a nutlin analogue created by employing the strategy of molecular simplification. METHODS: LQFM030 (2) cytotoxicity was evaluated in Ehrlich ascites tumour (EAT) cells, p53 wild type, by the trypan blue exclusion test, and the mechanisms involved in EAT cell death were investigated by light and fluorescence microscopy, flow cytometry, real-time PCR and Western blotting. KEY FINDINGS: Our results demonstrate that LQFM030 has dose-dependent antiproliferative activity and cytotoxic activity on EAT cells, induces the accumulation of p53 protein and promotes cell cycle arrest and apoptosis. p53 gene transcription was unaffected by LQFM030 (2); however, MDM2 mRNA increased and MDM2 protein decreased. CONCLUSIONS: These results suggest that the small-molecule p53 activator LQFM030 (2) has the potential for further development as a novel cancer therapeutic agent.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Carcinoma de Ehrlich/metabolismo , Piperidinas/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Pirazóis/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Carcinoma de Ehrlich/tratamento farmacológico , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Imidazóis/farmacologia , Camundongos , Piperidinas/síntese química , Piperidinas/farmacologia , Pirazóis/síntese química , Pirazóis/farmacologia , RNA Mensageiro/metabolismoRESUMO
Punica granatum L., Punicaceae, amplamente usada no Brasil, foi avaliada quanto ao seu potencial antitumoral in vitroe in vivo. Investigou-se in vitro a citotoxicidade do extrato etanólico do fruto e folha da P. granatumutilizando células K-562 e células do Tumor Ascítico de Ehrlich (TAE), pelos métodos de redução do MTT e exclusão do azul de tripano. Nos estudos in vivoavaliou-se o aumento da sobrevida de animais portadores do TAE e tratados, por via oral, com diferentes doses dos extratos etanólicos da P. granatum(12,5; 25; 50 e 100 mg/kg) por dez dias consecutivos. Além disso, nestes animais analisou-se o potencial de inibição tumoral e a atividade antiangiogênica da P. granatum. Os resultados dos estudos in vitrodemonstraram uma redução na viabilidade das células K-562 e do TAE, concentração-dependente, nos métodos investigados. Os resultados in vivo demonstraram aumento da sobrevida dos animais portadores do TAE tratados, de forma dose-dependente. Em paralelo, observou-se diminuição do número de células tumorais na cavidade peritoneal dos animais portadores e tratados. Além disto, os tratamentos empregados reduziram o padrão de vascularização da parede abdominal. Dessa forma, os dados apresentados revelaram que o extrato de P. granatumpossui atividade antitumoral in vitroe in vivo em paralelo a redução da angiogênese peritoneal.
Punica granatum L., a plant widely used in Brazil, was tested for its antitumor and antiangiogenic activities in vitroand in vivo. In this work, the in vitrocytotoxicity was evaluated using the K-562 cell line and Ehrlich ascites tumour cells, by MTT tetrazolium reduction test and the trypan blue exclusion test. In vivostudies investigated the increase in the survival time of Ehrlich tumour-bearing mice after treatment with different doses of Punica granatumL. ethanol extract (12.5; 25; 50 e and 100 mg/kg), by gavages, for ten consecutive days. In addition, we also investigated the tumour inhibition potential and antiangiogenic activity of this plant. In vitroresults demonstrated a decrease of K-562 and Ehrlich ascites tumour cells viability, with both methods used, in a dependent-manner concentration. In vivoresults showed a significant antitumor activity against Ehrlich ascites tumour growth, increasing survival time. In parallel, we detected a significant inhibition of the tumour growth, along with a decrease in the vascular pattern of the peritoneal wall. Thus, the data presented herein clearly showed that Punica granatum L. has antitumor and antiangiogenic activities.
RESUMO
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 percent, 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.