Figure 6.

Combination of bortezomib and citreoviridin inhibited cell cycle progression through different cell cycle regulators. Cells treated with or without 0.1 μM citreoviridin (Citreo) and 10 nM bortezomib (Btz) for 48 h were subjected to cell cycle analysis or harvested for western blotting analysis. Cell cycles distributed in the (a) G₀/G₁, (b) S, and (c) G₂/M phases were quantified. *P-values of <0.01 show that treatment effects differed significantly from those on the DMSO control. (d) Protein expression levels of the cell cycle regulators and CKIs from cells treated for 48 h were normalized to actin and DMSO (−/−) levels. For the phosphorylated form of the indicated proteins, the level of phosphorylation was further normalized to the total level of the given protein