ABCC2 siRNA increased the intracellular accumulation of cisplatin. (A) A typical chromatogram for total analysis of cisplatin from CNE2 cells exposed to cisplatin for 2 h using HPLC determination. (B) Calibration curve for gradient concentration of cisplatin within the range of 5–80 μg/ml. A typical linear relationship (R2 = 0.9965) was found between peak height and concentration of cisplatin. (C) The cellular accumulation of cisplatin in CNE2 cells treated with ABCC2-shRNA construct (ShABCC2-1 and shABCC2-2) and negative construct (ShABCC2-). The concentration of cisplatin were determined according to the calibration curve of cisplatin. Data were expressed as mean ± SEM value. N = 3, *P < 0.05 vs. CNE2.