Clinical relationship between MDR1 gene and gallbladder cancer.

Background: The most common mechanisms of multidrug resistance (MDR) in cancer cells is the expression of an energy-dependent exfflux pump. P-glycoprotein (P-gp) encoded by MDR1 gene and multidrug associated protein (MRP) are well known proteins associated with MDR. In human cancers, the MDR1 gene expression is common in patients with intrinsic and acquired MDR.