P-glycoprotein (P-gp), a member of the ABC superfamily of structural transporters that have been extensively studied, is encoded by MDR1 (Panczyk et al., 2007), is widely distributed in tissues such as the brain, lung, liver, kidney and gastrointestinal tract (Gupta et al., 2015), and is highly expressed within tumor cells, which confers drug resistance (Ambudkar, 1995; Li et al., 2016). The gene discussed is ABCB1; the disease is neoplasm.