Figure 3. Icaritin inhibits irradiation-induced phosphorylation of ERK1/2 and AKT.

(A) p-ERK1/2 assay. 4T1 cells were treated with vehicle alone or Icaritin at13 uM for 4 hr, and then irradiated with 0, 1, 4, or 6 Gy. Ten minutes later, the cells were fixed with 4% formalin for 5 min and subjected to an in-plate ELISA-like test with rabbit anti-phosphorylated ERK followed by horseradish peroxidase-anti-rabbit and a TMB substrate and A₄₅₀ reading. (B) p-AKT assay: 4T1 cells were treated with vehicle alone or Icaritin at 3 uM for 24 hr, and then irradiated with 0, 1, 4, or 6 Gy; One hour later, the cells were fixed with 4% formalin and subjected to an in-plate ELISA-like assay using rabbit anti-phosphorylated AKT as first antibody followed by the same method as detection for phosphorylated ERK1/2. ∗ represents p<0.05; ∗∗ represents p<0.01; NS means not significant.