Effect of vitamin K_(3) on apoptosis induced by androgen - independent prostate cancer cell PC-3M

AIM:To study the effect of vitamin K3(VK3) on the induction of apoptosis in androgen-independent prostate cancer cell PC-3M in vitro.METHODS:Cell viability was estimated by MTT assay.AO/EB staining was performed to detect apoptotic cells.Apoptosis and the changes of cell cycle were detected by flow cytometry.NAC was used to observe the effect of growth inhibition by VK3.RT-PCR was used to confirm the changes in gene expression.Levels of intracellular peroxides were estimated by using an oxidation-sensitive fluorescent probe DCFH-DA.RESULTS:PC-3M cells growth was significantly inhibited by VK3(≥60 μmol/L,P0.05).The inhibitory effect was time and dosage dependent.The result of AO/EB staining showed that apoptosis of PC-3M cells were induced by VK3.A typical subdiploid peak before G0/G1 phase was observed after treated for 12 h with VK3(60 μmol/L) by flow cytometry.The effect of growth inhibition treated with VK3 was antagonized by antioxygen NAC(5,10,20,40,80 μmol/L).An increase in the level of DCF fluorescence after PC-3M cells were treated for 1-2 h with VK3 was observed.Antioxidase GSH-Px and CAT were run-down after treated with VK3.CONCLUSION:The results indicate that apoptosis in PC-3M cells is induced through oxidative stress by VK3.