ERBB2 and breast cancer: Ligands-tagged nanotherapheutics synthesized using different conjugation techniques (Figure 4, Figure 5 and Figure 6) could selectively identify and bind to the receptors like EGFR, FR, Tf receptor, HER2, LHRH receptor, αvβ3, and CD-44 overexpressed on the surface of breast cancer cells and could facilitate cellular internalization through receptor-mediated endocytosis.