MAPK8 and breast cancer: ICA-1S may have an inhibitory effect on the MAPK/JNK pathway proteins, as treatment with the IC50 concentration of ICA-1S has shown significant decrease in the MAPK/JNK pathway proteins in both BT-549 and MCF-7 breast cancer cell lines.The results (Figure 4) demonstrate a decrease in both the phosphorylation levels and the total protein levels.