Certainly evidence suggests that coincident loss of p53 function or p53 mutation in HER2/neu-positive breast cancers is likely frequent and is associated with poor survival [34–36], which could explain our findings that JNK inhibition by SP600125 treatment induces Caspase-3-dependent cell death and impairs tumor growth in the JIMT-1 model as these cells are mutant for TP53 [37]. Here, MAPK8 is linked to breast cancer.