BTK and liver cancer: Identical ROIs were drawn on left forelegs of ATK and control groups, and the uptake values were 0.591 ± 0.151% and 0.017 ± 0.011% ID/g (n=5), respectively (P<0.05), indicating that the ATK gene drug carrier targeted liver cancer and can be successfully expressed in vivo and detected by micro-PET/CT.