Kitazaki et al. in 2005 reported that gefitinib reversed the resistance caused by ABCB1 to PTX and docetaxel in ABCB1 overexpressing PC-6 PTX lung cancer and MCF-7/Adr breast cancer cells and also increases the intracellular accumulation of rhodamine-123 in ABCB1 overexpressing cells [134]. The gene discussed is ABCB1; the disease is breast carcinoma.