Vis-à-vis the underlying molecular pathways of PAMAMs on cell viability and apoptosis as well as colony formation of HER2-positive breast cancer cells, we assumed that HER1 and 2 activation and c-Jun N-terminal kinase (JNK) in addition to ERK1/2 could have major roles in regulating these events; therefore, the expression patterns of HER1 and 2, as well as JNK1/2/3 and ERK1/2, were explored. This evidence concerns the gene MAPK3 and breast cancer.