APEX1 and cancer: In gallbladder cancer tissues, the amount of the long form of APE1 (37 kDa) was significantly higher when compared with normal gallbladder (P = 0.008) and chronic cholecystitis (P= 0.03) (Fig 1.B) while the relative expression level of the short form (35 kDa) was not significantly different in cancer tissues from the other two (Fig 1.C).