인간 전립선 암세포 PC-3 세포에서 Silibinin의 세포주기조절을 통한 세포사멸 유도 효과

Abstract

Milk thistle (silybum marianum) is a famous dietary supplement widely used in the United States and Europe. Silbinin is a major biologically active compound of milk thistle and has strong antioxidant and radical scavenger activities. Anticancer activities, as well as chemopreventive effects on various cancer cell lines, including prostate, lung, colon, skin, and bladder, have also been reported in silbinin. In the present study, we investigated the anticancer effects of silibinin and apoptosis through cell cycle arrest on prostate cancer cell PC-3. We performed cell viability by MTT assay and western blotting to confirm cell cycle check point proteins such as cyclin A/D1/E and cyclin-dependent kinase (CDK) 2/4/6. To quantify silibinin-induced apoptotic cell death of PC-3, Annexin V and PI double staining was performed by flow cytometry, by which its cell distribution was determined. As a result, silibinin inhibited the cell growth of PC-3 cells in a time- and dose-dependent manner, and its treatment resulted in cell cycle arrest at the G1 phase. Also the level of cell cycle check point proteins (cyclin, CDK) was decreased by silibinin in a dose-dependent manner. Taken together, we suggest that apoptosis of prostate cancer cell line PC-3 induced by silibinin is associated with cell cycle arrest through decrease of cell cycle check point proteins, caspase-3 activation and poly (ADP-ribose) polymerase (PARP) cleavage.