Figure 5.

Bioluminescence imaging of CycE-Luc reporter for monitoring antitumor efficacy of 5-FU in vitro and in vivo. (A-D) After treatment with 5-FU (0.5 µg/µl and 1 µg/µl) for 20 h, the expression of the reporter and bioluminescence imaging of HeLa-CycE-Luc cells were analyzed by immunoblotting (A) or assayed for luciferase activity (B), respectively. Meanwhile, the change of cell content (C) and cell cycle distribution (D) by 5-FU treatment were analyzed by flow cytometer. All the experiments repeated three times. Error bars indicate standard error. (E-G) HeLa cyclin E-Luc cells were injected subcutaneously into the right flank of BALB/C nude mice. When tumor nodule was about 100 mm³, PBS (n=5), MG132 (2 mg/kg per mouse, n=5) or 5-FU (25 mg/kg per mouse, n=5) was i.p. injected into nude mice, the bioluminescent images (E) were obtained 0, 24 and 48 h after injection, and relative induction folds of bioluminescent signal was calculated and normalized (F). Finally, 48 h after 5-FU treatment, tumor mass was removed and paraffin embedded sections were stained with cyclin E antibody (G). All the groups have four replicates and the experiments were repeated for three times. Error bars indicate standard error. *: p<0.05; **: p<0.01.