TRAIL-resistant breast cancer cells became more sensitive after vorinostat treatment in BALB/c nude mice because vorinostat inhibited the expression of NF-κB, cyclin D1, Bcl-2, Bcl-xL, VEGF, MMP-2, MMP-9, HIF-1α, IL-6, IL-8, increased the expression of DR4, DR5, p21, PUMA, TIMP-1, TIMP-2, Bax, Bak, Bim and Noxa (34). This evidence concerns the gene BAK1 and breast cancer.