We　recently　defined　cancer　metastatic　chemoprevention　as　utilizing　safe　and　effective　molecules　to　comprehensively　prevent　the　spark　of　activation-adhesion-extravasation-proliferation　metastatic　cascade　caused　by　circulating　tumor　cells　(CTCs).　The　strategy　focuses　on　preventing　the　most　important　starting　point　of　the　cascade.　We　identified　an　extract　from　a　well-known　medical　plant　Murraya　paniculata,　which　inhibited　both　embryonic　implantation　to　human　endometrium　as　traditionally-used　for　abortion　and　CTC　adhesion　to　human　endothelium.　Here,　we　separated　and　characterized　five　coumarin-containing　components　(Z1-Z5)　from　the　botanic　extract.　Flow　cytometry　revealed　that　within　1-100　mu　g/mL,　Z3　and　Z5　down-regulated　EpCAM　expression　in　human　colon　HCT116,　whereas,　Z1　and　Z2　did　oppositely.　Warfarin　and　Z1-Z5　component　mixture　(CM)　also　downregulated　EpCAM　expression.　The　down-regulation　of　EpCAM　by　Z3,　Z5,　CM　and　warfarin　was　confirmed　by　western　blotting,　and　caused　inhibition　on　adhesion　of　cancer　cells　to　human　endothelial　cells.　Rat　coagulation　study　showed　that　warfarin　prolonged　prothrombin　time,　whereas,　Z3　did　not.　The　present　studies　revealed　that,　for　the　first　time,　warfarin　and　coumarin-like　components　Z3,　Z5　and　CM　from　Murraya　paniculata　could　directly　inhibit　EpCAM-mediated　cell-cell　adhesion.