['Earlier, we reported the strong preventive efficacy of silibinin against colorectal cancer (CRC), but its usefulness against established CRC or effect of its withdrawal on CRC growth remained unknown. Present study focused on these important issues by employing two different treatment protocols in advanced human CRC SW480 xenograft in nude mice.', 'In the first treatment protocol, silibinin was fed for 28\xa0days (200\xa0mg/kg body weight, 5\xa0days/week) to mice with growing SW480 xenograft; thereafter, tumor growth was monitored for additional 3\xa0weeks without silibinin treatment. In the second protocol, silibinin treatment was started after 25\xa0days of SW480 cells injection (established tumors), and tumor growth was studied 4\xa0days, 8\xa0days and 16\xa0days after silibinin treatment.', 'In both treatment protocols, silibinin had strong and sustained inhibitory effect on xenograft growth. Detailed xenograft analyses showed that silibinin, in both treatment protocols, exerts anti-proliferative, pro-apoptotic and anti-angiogenic effects. Further, silibinin reduced the expression of β-catenin and phospho-GSK3β in xenograft tissues. Silibinin also targeted signaling molecules involved in CRC proliferation and survival (cyclin D1, c-Myc and survivin) as well as angiogenesis regulators (VEGF and iNOS).'] Does silibinin exert sustained growth suppressive effect against human colon carcinoma SW480 xenograft by targeting multiple signaling molecules?