title: Safrole induces cell death in human tongue squamous cancer SCC-4 cells through mitochondria-dependent caspase activation cascade apoptotic signaling pathways.
abstract: Safrole is one of important food-borne phytotoxin that exhibits in many natural products such as oil of sassafras and spices such as anise, basil, nutmeg, and pepper. This study was performed to elucidate safrole-induced apoptosis in human tongue squamous carcinoma SCC-4 cells. The effect of safrole on apoptosis was measured by flow cytometry and DAPI staining and its regulatory molecules were studied by Western blotting analysis. Safrole-induced apoptosis was accompanied with up-regulation of the protein expression of Bax and Bid and down-regulation of the protein levels of Bcl-2 (up-regulation of the ratio of Bax/Bcl-2), resulting in cytochrome c release, promoted Apaf-1 level and sequential activation of caspase-9 and caspase-3 in a time-dependent manner. We also used real-time PCR to show safrole promoted the mRNA expressions of caspase-3, -8, and -9 in SCC-4 cells. These findings indicate that safrole has a cytotoxic effect in human tongue squamous carcinoma SCC-4 cells by inducing apoptosis. The induction of apoptosis of SCC-4 cells by safrole is involved in mitochondria- and caspase-dependent signal pathways.
authors: Department of Dental Hygiene, China Medical University, Taichung 404, Taiwan.
authors: Fu-Shun
authors: FS
authors: Yu
authors: An-Cheng
authors: AC
authors: Huang
authors: Jai-Sing
authors: JS
authors: Yang
authors: Chun-Shu
authors: CS
authors: Yu
authors: Chi-Cheng
authors: CC
authors: Lu
authors: Jo-Hua
authors: JH
authors: Chiang
authors: Chang-Fang
authors: CF
authors: Chiu
authors: Jing-Gung
authors: JG
authors: Chung