Marina A. Naves¹, Liany J. Luna¹, Angélica E. Graminha¹, Alzir A. Batista², Marcia R. Cominetti¹

Objectives: This study aims to evaluate the effects of the complex [Ru(AG)(dppe)2]PF6, composed by ruthenium and galic acid, as a potential antitumor agent. This compound was tested in a triple-negative breast cancer (TNBC) cell line MDA-MB-231. The effects on cytotoxicity and morphology of cells were investigated. Methodology: [Ru(AG)(dppe)2]PF6 was synthesized and provided by the Department of Chemistry of the Federal University of São Carlos. To evaluate the effects of this complex on TNBC cells morphology, these were exposed to different concentrations (0.049 to 25µM) of the compound and photos were taken in different times of treatment (2, 4, 8, 24 and 48h). The inhibition of cell proliferation was evaluated through a MTT colorimetric assay, where cells were exposed to different concentrations of treatment (0.0122 to 75µM) for 48h, along with the IC50 determination. A clonogenic assay was conducted to evaluate the cytotoxic and cytostatic effects of the complex. In this assay, cells were exposed to different concentrations of treatment (0.0122 to 0.78µM) for 48h, and after 10 days of incubation, the size and quantity of colonies of cells formed were measured. Results: The sensibility of cells to [Ru(AG)(dppe)2]PF6 can be seen in the morphology assay, in which cells structure begins to alter in 8h at 12.5µM, in 24h at 6.25µM and in 48h at 0.195µM, with cell death at higher concentrations in the same times. The IC50 value for [Ru(AG)(dppe)2]PF6 over MDA-MB-231 cell proliferation was 0.80µM. The complex had concentration-response cytotoxic effects observed in the MTT and in the clonogenic assays. Conclusion: The results suggest that the [Ru(AG)(dppe)2]PF6 complex affects the structure and proliferation of MDA-MB-231 TNBC cell line in a concentration-response manner, which makes this compound an interesting alternative in the study of future pharmaceuticals with potential and less aggressive antitumor effects.

Keywords: breast cancer, triple-negative, antitumor effects, ruthenium.”