Effects of EGCG on proliferation of human bladder carcinoma T24 cells

Objective The present study was undertaken to study the effects of(-)-epigallocatechin gallate(EGCG) on growth inhibition and cell cycle,and to investigate the corresponding molecular mechanism of T24 cells.Methods The cytotoxic,antiproliferative and cell cycle arrest effects of EGCG on T24 cells were determined with varying concentration of EGCG treatment for 24 hours by MTT assay,anchorage-dependent colony-forming assay and flow cytometry.The cell cycle modulating protein Cyclin D1 and CDK4 were determined by immunoblotting.Results Inhibitory rates of cell viability treated with EGCG at concentrations of 20-100 μg/mL after 24 hours ranged from 4% to 61%.EGCG at dosages of 40,80 and 100 μg/mL inhibited the proliferation of cells significantly(P0.05).There was a drastic decrease in the ability of the T24 cells to form colonies with increasing doses of EGCG(10-40 μg/mL) and EGCG at dosages of 20 and 40 μg/mL completely inhibited the proliferation of cells without any colony forming.The T24 cells treated with EGCG resulted in significant G0/G1-phase cell cycle arrest and dose-dependent downmodulation of the protein expression of Cyclin D1 and CDK4.Conclusion EGCG could significantly inhibit proliferation and induce G0/G1-phase cell cycle arrest of T24 cells which might be relative to prohibition of Cyclin D1 and CDK4 expression.