Preliminary Investigation On The Effect Of Resveratrol On Human Esophageal Carcinoma EC109 Cells

[Backgroud and Objectives]Resveratrol (trans-3,4',5-trihydroxystilbene), is a naturally occurring polyphenoliccompound highly enriched in grapes, peanuts, red wine .It has been reported to exhibit a widerange of biological and pharmacological properties.Resveratrol plays function as an antioxidantand reduces the risk of developing coronary heart disease, likely through its modulation of lipidmetabolism and prevention of the low density lipoprotein oxidation, as well as inhibition ofeicosanoid production and platelet aggregation. Most recently, it has been shown that resveratrolcan act as a cancer chemopreventive agent,and induce apoptosis in multiple carcinoma cellsthrough interfering with signal transduction pathways and modulating cell cycle-regulatingproteins.The present study was designed to explore the effect of resveratrol in suppressinggrowth and inducing apoptosis in human esophageal carcinoma EC109 cells and to determinepreliminarily the potential mechanism of resveratrol on esophageal cancer cells ,to provide anadjuvant therapeutic clue for better treatment of human esophageal carcinoma.[Methods]EC109 cells were treated with resveratrol at different concentration. Methylthia-zolyltetrazolium (MTT) assay was used to measure the effect of resveratrol on growth of EC 109cells. Phase contrast microscope and Hoechest 33258 staining were used to observe the apoptosisstatus of EC109 cells. DNA fragmentation was used to examine cell apoptosis. Theultrastructural changes of EC109 cells were observed with transmission electron microscope.The effect of resveratrol on cell cycle and apoptosis was analyzed by flow cytometry. Theexpression changes of Annexin I in EC109 cells induced by resveratrol were detected byWestern Blot.[Results ]Resveratrol significantly inhibited the growth and proliferation of EC109 cells in time anddose dependent manner. 48h after treated with resveratrol, the typical apoptosis morphologicalchanges was observed under phase contrast microscope and fluorescence microscope in 500μ mol/L treatment groups. The results of DNA agarose gelelectrophoresis showed that DNA ladderappeared obviously at 500μmol/L Res-treated groups.The ultrastructural changes of EC109cells treated with resveratrol were as following: the number of microvillus on the surface ofplasma membrane decreased and cavitations can be observed and chromatin margination wasfrequent in nucleolus. Resveratrol affected EC109 cell cycle distribution and arrested EC 109 cellin S-phase accompanied with reducing G₀/G₁ phase cells. Sub-G1 peak appeared obviously altertreatment with 125, 250, 500μmol/L resveratrol when detected by flow cytometry. The ratio ofAnnexinI/β-actin were 0.1514 , 0.2019 , 1.2877 , 1.3263 , 1.8854 , 1.9585 ,2.0457,respectively, when treated with resveratrol for 0, 1, 3, 6, 12, 24 and 48h measured bywestern blot. Resveratrol enchanced the expression of Annexin I in time-dependent manner.[Conclusions]Resveratrol can inhibit the growth and proliferation of EC109 cells in time-anddose-dependent manner. Resveratrol can induce the cell cycle arrest in the S phase of ECI09cells, inhibit DNA synthesis and induce cell apoptosis in dose-dependent manner.Resveratrol canup-regulate the expression ofAnnexin I in time-dependent manner.