1.Bupleuri Radix prevents the progression of polyps of the colon human by affecting human angiotensin II2.Bupleuri Radix inhibits the risk of polyps of the colon human by reducing oxidative stress via down-regulation of human angiotensin II3.Bupleuri Radix prevents the progression of polyps of the colon human by affecting angiotensin II- induced PKC/NAD(P)H oxidase pathway.