Figure 11. Subcutaneous injection of 5*10⁶ ACHN cells per nude mouse was carried out.

At 2 weeks (set as day 0), treatment was initiated and tumor lengths and widths were measured every 4 days. Tumor volume was derived as length × width ²/2. Sorafenib at 30 mg/kg daily inhibited tumor growth; however, in sorafenib resistant xenografts, no obvious difference was found between the vehicle and sorafenib groups. Interestingly, treatment with ubenimex at 20 mg/kg daily reversed the resistance of the xenografts.