Then, we conducted cell viability assays after treatment of a panel of commonly used chemotherapy agents for BC, including microtubule stabilizer (paclitaxel), DNA topoisomerase IIα (TOP2A) inhibitor (doxorubicin; Dox), antimetabolite (5-fluorouracil; 5-FU) and DNA alkylating agent [cis-diammineplatinum(II); cisplatin]. This evidence concerns the gene TOP2A and breast cancer.