The Effect of Gnidilatimonoein from Daphne mucronata, on the Adhesive Property of Human Platelets

The adhesive interaction between tumor cells and the host cells or the extracellular matrix plays a crucial role in tumor metastasis. To evaluate the mediation of cell adhesion by Daphne mucronata, an anti-cancer medicinal plant in Iranian folk medicine, the adhesion of thrombin activated human platelets to the cultured monocytes or HL-60 cells was investigated under the effect of the plant extract (0.54 mg/ml) or one of its purified components (gnidilatimonoein, 0.94 µM). Treatment of the platelets with the plant extract or the active component, for various time intervals, followed by their activation by thrombin resulted in 80-90% reduction in the number of monocytes with more than 10 attached platelets. Similarly, under almost all identical conditions, the adhesion of the activated platelets to HL- 60 cells was decreased by 90%. The adhesion of thrombin activated human platelets to the plant treated HL-60 cells was also reduced significantly (by 95%). These data clearly indicate that Daphne mucronata is capable of mediating tumor metastasis through effecting cell adhesion properties of the