(A) Effects of gemcitabine (Gem), 18, and 26 on end point primary tumor volume in an orthotopic xenograft pancreatic cancer model. Mice received oral gemcitabine 75 mg/kg twice weekly or daily intraperitoneal injections of 18 or 26 (10 mg/kg) for 28 days. Data represent the mean ± SEM (n = 4 per group). (B) Number of mice with histologically confirmed liver metastases after receiving gemcitabine, 18, and 26 (n = 4 per group): (∗) p = 0.0285 vs vehicle, χ2 test.