RESUMEN
Purpose:To study the effect of EGCG(extracts fr om green tea) on cell cycle in human breast cancer cell line and its mechanism. Methods:Cell proliferation assay kit was used to produce the dose-response curve. Flow cytometric assay was used to evaluate the cell cycle changes on MDA-MB435 cells with and without EGCG. The expression of protein was detected by Western blot. Results:EGCG could inhibit the proliferation of the breast canc er cells MDA-MB-435, 40 ?g/ml EGCG induced G 0 /G 1 phase arrest and the entrance to S phase. Both mRNA and protein level of p21 waf1/cip1 were up regulated in MDA-MB435 cells when treated by 40?g/ml EGCG. Conclus ions:Green tea can inhibit the growth of human breast cancer cells, perhaps by means of p21 and therefore inhibiting the progression of the cell cycle.