To investigate whether Epigallocatechin-3-gallate （EGCG） can induce apoptosis of the gastric cancer cell line MKN45 and its apoptotic pathway.METHODS： To determine this, apoptotic rates of MKN45 cells after EGCG tr...To investigate whether Epigallocatechin-3-gallate （EGCG） can induce apoptosis of the gastric cancer cell line MKN45 and its apoptotic pathway.METHODS： To determine this, apoptotic rates of MKN45 cells after EGCG treatment with or without caspase-3 inhibitor were evaluated by Annexin V-FITC ＋ PI staining The influence of EGCG on the activity of caspase-3 in the MKN45 cells was determined by ELISA. By Rhodamine123 staining, the membrane potential change of the mitochondrion was also investigated, and mRNAs and protein expression of the bcl-2 family were analyzed by RT-PCR and Western blot.RESULTS： EGCG can induce apoptosis of MKN45 cells in time- and dose-dependent manner. Eight hours after EGCG treatment, the activity of caspase-3 in the MKN45 increased, especially 12 h after treatment. The mitochondrial membrane potential was significantly weakened 4 h after EGCG insult. The mRNA and protein expression levels of pro-apoptotic members, such as Bax, Bid and Bad, were upregulated gradually as treated time increased. Moreover, the mRNA and protein expression levels of anti-apoptotic members, such as Bcl-xL and Bcl-2, were inhibited. CONCLUSION： These data support that EGCG can induce apoptosis of the human gastric cancer cell line MKN45, and the effect is in a time- and dose-dependent manner. The apoptotic pathway triggered by EGCG in MKN45 is mitochondrial-dependent.展开更多
基金Supported by a grant from Shanghai Leading Academic Discipline Project, No.Y0205
文摘To investigate whether Epigallocatechin-3-gallate （EGCG） can induce apoptosis of the gastric cancer cell line MKN45 and its apoptotic pathway.METHODS： To determine this, apoptotic rates of MKN45 cells after EGCG treatment with or without caspase-3 inhibitor were evaluated by Annexin V-FITC ＋ PI staining The influence of EGCG on the activity of caspase-3 in the MKN45 cells was determined by ELISA. By Rhodamine123 staining, the membrane potential change of the mitochondrion was also investigated, and mRNAs and protein expression of the bcl-2 family were analyzed by RT-PCR and Western blot.RESULTS： EGCG can induce apoptosis of MKN45 cells in time- and dose-dependent manner. Eight hours after EGCG treatment, the activity of caspase-3 in the MKN45 increased, especially 12 h after treatment. The mitochondrial membrane potential was significantly weakened 4 h after EGCG insult. The mRNA and protein expression levels of pro-apoptotic members, such as Bax, Bid and Bad, were upregulated gradually as treated time increased. Moreover, the mRNA and protein expression levels of anti-apoptotic members, such as Bcl-xL and Bcl-2, were inhibited. CONCLUSION： These data support that EGCG can induce apoptosis of the human gastric cancer cell line MKN45, and the effect is in a time- and dose-dependent manner. The apoptotic pathway triggered by EGCG in MKN45 is mitochondrial-dependent.
