Emerging therapeutic strategies for triple-negative breast cancer using ruthenium, iridium, and rhenium complexes.

Triple-negative breast cancer (TNBC) is an aggressive disease with limited treatment options due to the absence of ER, PR, and HER2 receptors. This review summarises the recent progress in the use of ruthenium, iridium, and rhenium complexes as alternative therapeutic agents for TNBC. These metal complexes are designed to respond to tumor-specific biomarkers or the tumor microenvironment, enabling selective uptake and enhanced anticancer activity. Through redox reactions and light activation, they generate reactive oxygen species, disrupt mitochondrial function, and induce cancer cell death. Overall, ruthenium, iridium, and rhenium complexes offer a multi-mechanistic and targeted approach that may help overcome resistance and improve future TNBC treatment strategies.