MAPK3 and breast cancer: No significant differences were observed for Phosphorylated ERK1/2 (pERK1, Thr 202/Tyr 204; pERK2, Thr185/Tyr187) (Figure 3c) and NFĸB-p65 protein expression in the MDA-MB-231 breast cancer cells either treated with, or without doxorubicin (Figure 3d).