Fig. 6

Involvement of the MAPK pathway in C-phycocyanin-induced cell death. a Effect of C-phycocyanin on the PI3K/AKT signaling in MDA-MB-231 cells. After treatments, the expression levels of p-AKT and total AKT were analyzed by Western blotting. b Effect of C-phycocyanin on the MAPK signaling in MDA-MB-231 cells. After treatments, the levels of ERK1/2, JNK and p38 MAPK and their phosphorylated forms were analyzed by Western blotting. c The effects of inhibitors (SB203580 or SP600125) on cell viability were evaluated by CCK-8 assay. Significant difference compared with control group are indicated as *P < 0.05, **P < 0.005, and ^# P > 0.05. d The effects of PD98059 on the levels of COX-2, CDK2, CDK4, Cyclin D1, Cyclin E, p21 and p27 were evaluated by Western blotting