Study On Sesamin Inducing Apoptosis Of HepG2Cells And Its Mechanism

Cancer is a kind of disease threating seriously to human. In recent years, manystudies showed that the incidence of cancer is on the rise and sufferers lean to loweringages.Bcl-2(B cell lymphoma leukemia-2) protein family is a class of proteins that werestudied mostly in proteins related to apoptosis. The members of this family contain anti-apoptotic proteins such as Bcl-2, Bcl-xL and pro-apoptotic proteins such as Bax. Theywork synergistically to regulate cell apoptosis. NF-κB (Nuclear Factor-κB) is an importanttranscription factor which plays an important role in the signaling pathway of cellapoptosis. NF-κB is the most important anti-apoptotic regulators of Bcl-2familymeanwhile.Sesamin is a major lignan constituent of sesame exists in a variety of plants.Previous studies have reported that sesamin could inhibit the cancer cell growth. However,the mechanism remains unknown. Here, we investigated this using human hepatocellularcarcinoma cell line HepG2and results are as follows:(1) The effect of sesamin on the cell growth was examined by MTT assay. Wefound that the HepG2cell growth was inhibited by sesamin.(2) The apoptosis of HepG2cells was determined by Hoechst33258stainingand flow cytometry analysis. We found that sesamin induced apoptosis in HepG2cells.(3) Bcl-2, Bcl-xL and Bax were investigated at transcriptional and translationallevels by RT-PCR and Western blot in HepG2cells. We found that sesamin down-regulated Bcl-2and Bcl-xL. Finally, we analyzed the nuclear transition of NF-κB inHepG2cells and found that it was inhibited by sesamin.These results preliminarily clarify the mechanism that explains the anticanceractivity of sesamin.