Inductive effect of phytoglycoprotein (38 kDa) on G₀/G₁ arrest and apoptosis in diethylnitrosamine-treated ICR mice.

Promotion in the carcinogenic stage is closely related to the growth and proliferation of liver cancer cells. The purpose of this study was whether Styrax japonicum Siebold & Zuccarini (SJSZ) glycoprotein has preventive effect on the growth of hepatocarcinoma cells in diethylnitrosamine (DEN)-induced ICR mice. The study evaluated cell cycle and the activities of cell cycle-related factors [cyclin D1/cyclin dependent kinase (CDK) 4], cell cycle inhibitors (CKIs; p53, p21, and p27), proliferating cell nuclear antigen (PCNA), cytochrome c, Bid, caspase-3, and caspase-9 in DEN-induced ICR mice by flow cytometry, immunoblot analysis and qRT-PCR. The results showed that SJSZ glycoprotein (10 mg/kg, BW) arrested G(0)/G(1) phase and the activity of cyclin D1/CDK4, PCNA, and Bid. However, it induced activities of CKIs, cytochrome c, caspase-3, and caspase-9. Taken together, this present study suggested that SJSZ glycoprotein might be a potent inhibition of hepatic tumor promotion.