Mecanismos activados por calcitriol y menadiona en células de cáncer de mama

GUIZZARDI SOLANGE; LUCIANA BOHL; RODRIGUEZ VALERIA; PICOTTO GABRIELA; TOLOSA DE TALAMONI NORI

Congreso; LXI Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica; 2016

In a previous paper we have reported that menadione (MEN) potentiates the antiproliferative effect of 1,25 (OH) 2D3 (D) on MCF-7 breast cancer cells. The aim of the present study was to investigate about the mechanisms involved in that effect. To do this, MCF-7 cells were treated with 100 nM D, MEN 10 µM, both drugs or vehicle (ethanol) for 96 hours. The mitochondrial membrane potential and the measuring intracellular calcium (Ca+2) were assessed by flow cytometry. Superoxide anion and nitric oxide (NO) levels were measured by spectrophotometry. The expression of TRPV6 and PMCA1b mRNA levels were determined by quantitative real-time PCR. The production of acidic vesicular organelles (AVOs) was evaluated by fluorescence microscopy. Statistical analysis was performed by ANOVA / Bonferroni. At 96 hours of treatment, both D and the combined treatment induced increased NO production. Superoxide anion levels, mitochondrial permeability and the level TRPV6 and PMCA1b mRNA were enhanced only by the combined treatment as compared to the controls. The increment of AVOs suggests activation of cell death process. In conclusion, MEN increases the effect of D on MCF-7 cells through oxidative and nitrosative stress, alteration in the mitochondrial permeability, alteration in intracellular Ca+2 and changes of molecules gene expression related regulating cation, followed by cell death.