BRCA1 and breast cancer: However, to address whether the combinative treatment of such DNA-damaging agents can be extended to the triple-negative BRCA1-proficient breast cancer population, the anticancer activity of the well-known PARP inhibitor olaparib in combination with the antimetastatic ruthenium(II)–arene PTA compound RAPTA-T was investigated to treat triple-negative BRCA1-competent breast cancer cells (MDA-MB-468 and MDA-MB-231), with consideration of sporadic breast cancer MCF-7 cells.