RESUMEN
Antimetastatic activity, high selectivity and cytotoxicity for human tumor cell lines make ruthenium(ii) complexes attractive for the development of new chemotherapeutic agents for cancer treatment. In this study, cytotoxic activities and the possible mechanism of cell death induced by three ruthenium complexes were evaluated, [Ru(MIm)(bipy)(dppf)]PF6 (1), [RuCl(Im)(bipy)(dppf)]PF6 (2) and [Ru(tzdt)(bipy)(dppf)]PF6 (3). The results showed high cytotoxicity and selectivity indexes for the human triple-negative breast tumor cell line (MDA-MB-231) with IC50 value and selectivity index for complex 1 (IC50 = 0.33 ± 0.03 µM, SI = 4.48), complex 2 (IC50 = 0.80 ± 0.06 µM, SI = 2.31) and complex 3 (IC50 = 0.48 ± 0.02 µM, SI = 3.87). The mechanism of cell death induced in MDA-MB-231 cells, after treatment with complexes 1-3, indicated apoptosis of the cells as a consequence of the increase in the percentage of cells in the Sub-G1 phase in the cell cycle analysis, characteristic morphological changes and the presence of apoptotic cells labeled with Annexin-V. Multiple targets of action were identified for complexes 1 and 3 with an induction of DNA damage in cells treated with complexes 1 and 3, mitochondrial depolarization with a reduction in mitochondrial membrane potential, an increase in reactive oxygen species levels and increased expression levels of caspase 3 and p53. In addition, antimetastatic activities for complexes 1 and 3 were observed by inhibition of cell migration by the wound healing assay and Boyden chamber assay, as well as inhibition of angiogenesis caused by MDA-MB-231 tumor cells in the CAM model.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Complejos de Coordinación/farmacología , Compuestos Ferrosos/química , Rutenio/química , Animales , Antineoplásicos/química , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Células CACO-2 , Caspasa 3/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Membrana Corioalantoides/metabolismo , Complejos de Coordinación/química , Daño del ADN , Humanos , Células MCF-7 , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Silymarin (SM), a standardized extract derived from Silybum marianum (L.) Gaertn, is primarily composed of flavonolignans, with silibinin (SB) as its major active constituent. The present study aimed to evaluate the antigenotoxic activities of SM and SB using the alkaline comet assay in whole blood cells and to assess their effects on the expression of genes associated with carcinogenesis and chemopreventive processes. Different concentrations of SM or SB (1.0, 2.5, 5.0, and 7.5 mg/ml) were used in combination with the DNA damage-inducing agent methyl methanesulfonate (MMS, 800 µM) to evaluate their genoprotective potential. To investigate the role of SM and SB in modulating gene expression, we performed quantitative real-time PCR (qRT-PCR) analysis of five genes that are known to be involved in DNA damage, carcinogenesis, and/or chemopreventive mechanisms. Treatment with SM or SB was found to significantly reduce the genotoxicity of MMS, upregulate the expression of PTEN and BCL2, and downregulate the expression of BAX and ABL1. We observed no significant changes in ETV6 expression levels following treatment with SM or SB. In conclusion, both SM and SB exerted antigenotoxic activities and modulated the expression of genes related to cell protection against DNA damage.