Reactive OxygenSpecies Inducing Triazolylpyridine-BasedRu(II)/Ir(III) Complexes for Therapeutically Enhanced Triple-NegativeBreast Cancer Treatment

The effectiveness of existing systemic and targeted therapies remains limited in triple-negative breast cancer (TNBC) treatment. Much research has been conducted on reactive oxygen species (ROS)-mediated cancer cell death to overcome the shortcomings of the currently applied chemotherapeutic treatments. Herein, we have developed novel Ru(II)/Ir(III)-mediated triazolylpyridine complexes as ROS inducers. Upon entering the TNBC cells, the Ru(II) complex effectively accumulated in mitochondria and triggered the creation of ROS, facilitating dysfunction of mitochondria and oxidative DNA damage, ultimately causing death of cells through G2/M phase cell cycle arrest. Eventually, this complex induced the upregulation of BAX (pro-apoptotic protein) and downregulation of BCL-2 (antiapoptotic protein) and triggered the caspase 3/9 pathway and released cytochrome <i>c</i> in the cytosol for apoptosis. The complex <b>JRu</b> (Ru^II triazolylpyridine) significantly reduced the integrity and viability of TNBC 3D spheroids.