Molecular mechanism of Graptopetalum paraguayense E. Walther extracts induced growth inhibition and apoptosis in B16-F1 melanoma cell lines

• Main Authors: Hsing-Chung Liu, 劉馨中
• Other Authors: Su-Tze Chou
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/92zym5

碩士 === 靜宜大學 === 食品營養研究所 === 97 === Carcinoma is the major death in Taiwan, and there are an increasing number of people with melanoma skin cancer year after year. Recently, there are increase interest in the study how to prevention and delay the skin cancer development. Graptopetalum paraguayense E. Walther is belonging to the Crassvlaceae family and has been used as an herbal medicine. Our in-vitro study had showed that Graptopetalum paraguayense E. Walther (GP) extracts had antioxidant activities. In this study, the effects of 50% ethanolic extract from GP (GE50) on the growth and apoptosis induction of mouse melanoma cell lines (B16-F1) will be studied. The results demonstrated that GE50 can inhibit the cell growth and induce cell cycle arrest on S phase. The morphology, DAPI staining were conducted and they indicated that GE50 induced B16-F1 cells apoptosis. Flow cytometry assay demonstrated that GE50 induced the change of reactive oxygen species (ROS) , mitochondrial membrane potential, and calcium releasing. In mitochondrion pathway, GE50 inhibited the expression of Bcl-2, and increase the expression of cytochrome c, caspase-9, Apaf-1, caspase-3, AIF, Endo G and PARP. In extrinsic pathway, GE50 inhibited the expression of Fas and FasL. In MAPK family, GE50 can decresed the expression of ERK 1/2 and increased the expression of p38 and JNK. In endoplasmic (ER) stress, GE50 can increased the expression of GRP 78, GADD153 and caspase-12. We also used confocal laser microscope to show cytochrome c, AIF, Endo G and GADD153 are released. GE50 also can inhibit the invasiveness of melanoma cells by suppressing MMP-2, MMP-7 and MMP-9 expressions. In addition, GE50 increased the glutathione peroxidase activity, glutathione levels, and malondialdehyde level in B16-F1 cells. The results of this study were suggested that GE50 might inhibit cell growth and induced S phase arrest. GE50 induced apoptosis thought the activation of mitochondrial, Fas/FasL, MAPK and ER stress pathway. Subsequently, GE50 can decrease MMP-2, MMP-7 and MMP-9 expressions. Furthermore, our result demonstrated that GE50 could change antioxidant system in B16-F1 cells. The current evidence suggests that GE50 can inhibit the cell growth, induce apoptosis and inhibit invasiveness. The results suggested that Graptopetalum paraguayense might be work as a potential chemopreventive agent because of its anticancer properties.