Toxicogenetic evaluation and study of antiproliferative response mechanisms of ruthenium-based metallodrugs containing naphthoquinones ligands in tumor cells growing in conventional and 3D systems

Author(s)

Rone Aparecido De Grandis

• Document type: Doctoral Thesis
• Press: Araraquara. 2020-02-27.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Farmacêuticas. Araraquara
• Defense date: 2020-01-29
• Advisor: Fernando Rogério Pavan

Abstract

Recently, ruthenium complexes have occupied a leading position in the search for new anti-cancer therapies due to their potential of action, selectivity in tumor tissues and less toxicity compared to current platinum complexes. The diversity of ligands is crucial for these complexes to reach multiple biological targets and thus, overcome the limitation of contemporary therapies. One approach for multi-target molecules is the combination of bioactive ligands with recognized antitumor properties, such as natural naphthoquinones. Based on this, this study had proposed the evaluation and characterization of toxicogenetics and antitumor properties of eight new ruthenium complexes containing the natural ligands lapachol and lawsone. In general, the phosphinic series showed satisfactory antiproliferative activity against different cell lines, especially prostate carcinoma-derived cells. The IC50 values of these complexes were considerably lower than the values found for cisplatin. Furthermore, it was observed up to 28-fold selective for the complexes than cisplatin. Also, clonogenic assay suggests that the replacement of bipy ligand for phen increases the compound activity, inducing loss of DU-145 cells clonogenicity. Phosphinic complexes also described antiproliferative activities in three-dimensional (3D) cell models. In these assays, the lapachol-complexes have demonstrated cytotoxic activity independent of the hypoxia found in the spheroids. Besides, the results suggest that the DP-LP complex goes through the spheroid and destabilizes the cell aggregates, resulting in disruption of matrix-cell interactions. The DP-LP complex triggers apoptosis in DU-145 cells accompanied by an increase of cells in the G2 / M phase, which is consistent with the inhibition of AURORA-B protein activity. The central mechanism related to these effects is the presence of lapachol in DP-LP, which promotes the generation of intracellular reactive species that can cause DNA damage. DNA fragmentation, evidenced by comet assay, could activate the DNA repair systems that maintain the cells in the G2 / M checkpoint, due to a decrease of the AURKB gene expression. Also, DNA damage could activate caspases that conducted the DU-145 cells to apoptosis. In summary, the results found in this study contributed to the selection and elucidation of antiproliferative and cytotoxic properties of new compounds. We demonstrate the coordination of lapachol in a phosphinic ruthenium complex allowed the formation of compounds with potential impact in health targeting cancer treatment. (AU)

• FAPESP's process: 16/22429-7 - Toxicogenetics evaluation and study of antiproliferative response mechanisms of ruthenium-based metallodrugs containing naphthoquinones ligands in tumor cells growing in conventional and 3D systems
• Grantee: Rone Aparecido de Grandis
• Support Opportunities: Scholarships in Brazil - Doctorate