Photothermolysis Mediated by Gold Nanorods Conjugated with Epidermal Growth Factor Receptor (EGFR) Monoclonal Antibody Induces Apoptosis via the Mitochondrial Apoptosis Pathway in Laryngeal Squamous Cell Cancer

Abstract

Gold nanorods (AuNRs) have unique optical properties and biological affinity and can be used to treat tumors when conjugated with other protein molecules. Our previous studies have shown that EGFR monoclonal antibody (EGFRmAb)-modified AuNRs exert strong antitumor activity in vitro by inducing apoptosis. In this study, we tested the effects of EGFRmAb-modified AuNRs on laryngeal squamous cell cancer (LSCC) in vitro and in vivo. The in vitro results showed that EGFRmAb-modified AuNRs inhibited NP-69, BEAS-2B and Hep-2 cell growth and induced mitochondria-dependent apoptosis. The mitochondrial membrane potential was reduced, leading to the release of cytochrome C (Cyt C) and consequent activation of the intrinsic mitochondrial apoptosis pathway. Moreover, we observed that the occurrence of mitochondrial apoptosis is related to the destruction of the lysosome-mitochondria axis. To verify the effects in vivo, we also established a laryngeal tumor model in nude mice by subcutaneous transplantation. In model mice treated with EGFRmAb-modified AuNRs and irradiated with an NIR laser, tumor cell apoptosis and tumor growth were inhibited. These results suggest that EGFRmAb-modified AuNRs induced apoptosis through the intrinsic mitochondrial apoptotic pathway and are a potential candidate for cancer therapy.