Figure 4.

Tumor growth curves in CT26/tk-luc tumor-bearing mice. (A) Experimental design for the evaluation of therapeutic efficacy of tetrandrine (TET). Treatment was initiated when the tumor volume reached 100 mm³. Mice were randomly assigned to six groups: Control, 20, 10 and 5 mg/kg TET, radiation alone and combination. TET was administered every 4 days for 2 weeks in the 20 mg/kg group, every 2 days for 2 weeks in the 10 mg/kg group and for 12 consecutive days in the 5 mg/kg group by intraperitoneal injection (i.p.), i.e. 3, 6 and 12 fractions for a total of 60 mg/kg. For the radiation alone group, 3 Gy was administered every other day in 6 fractions, and for the combination group, 10 mg/kg TET or 3 Gy were alternately administered every day for 2 weeks. The red symbols indicate the time points for the administration of TET, while the downward brown arrows indicate irradiation. (B) Tumor growth curves of CT26/tk-luc tumor-bearing mice following different treatments. The time required to reach an 8-fold increase from the initial tumor volume was used as the endpoint for determining the tumor growth delay assays. n=7 for all mouse groups, except n=6 in the control group. *P<0.05 vs. the control, and ^#P^<0.05, the radiation alone group vs. the combination group.