The results revealed that compared with EVs, overexpression of BTBD7 significantly reduced the viability of MCF-7, BT474, and HCC1937 cells under drug treatment and increased apoptosis (all p < 0.01, Figures 6(b)–6(d)), suggesting that overexpression of BTBD7 reversed drug resistance of BC cells induced by EVs. This evidence concerns the gene BTBD7 and breast cancer.