Aptamer-Conjugated Gold Nanoparticles Targeting Human Epidermal Growth Factor Receptor 2 (HER2) for Cancer Theranostic, In Vitro Assays

The human epidermal growth factor receptor 2 (HER2) is a transmembrane glycoprotein overexpressed in several solid tumors, including breast and prostate cancer. HER2 has been associated with aggressiveness, a poor prognosis, resistance to therapy, and accelerated tumor growth. Recent advances in nanomedicine have shown potential for application in cancer detection. In this study, we designed a nanosystem (NS) based on gold nanoparticles (AuNPs) conjugated with a fluorescent HER2-specific aptamer to detect and treat HER2-positive cancer cells. The conjugate formation was characterized by UV-Visible spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Then, we evaluated the hemocompatibility and compared the cytotoxic effect between NS and trastuzumab in different cell lines. Fluorescence detection suggests that NS can specifically bind to cells with high HER2 expression. This preliminary study reveals the potential of aptamer-functionalized AuNPs as a theranostic tool in HER2-overexpressing cancer cells.