The same research group also showed that the affibody-bioconjugated CPNP15s were able to specifically enter HER2-overexpressed breast cancer cells (SKBR-3), while no uptake in non-HER2-overexpressed breast cancer cells (MCF-7) and normal cells (MIH-3T3 fibroblasts) could be observed (Figure 11) [45]. The gene discussed is ERBB2; the disease is breast cancer.