Gold nanoparticle surface chemistry affects multiple parameters of cytotoxicity in an ovarian cancer model

Abstract

Ovarian cancer is one of the deadliest types of cancer, and traditional treatments such as chemotherapy and radiation therapy cause harmful side effects to healthy tissue. Contemporary medicine has become more personalized, and the field of nanomedicine has developed in an attempt to develop more targeted cancer treatments to reduce these off-target effects. Gold nanoparticles (AuNP) are of particular interest because of their unique and modifiable physicochemical properties as well as high biocompatibility and low immunogenicity. This study investigated AuNP conjugated to four different ligands with distinct surface chemistry: polyethylene glycol (PEG), trimethylamine bromide (TMAB), 4-dimethylaminopyridine (DMAP), and carboxyl (COOH). The impact of AuNP surface chemistry upon various parameters of cytotoxicity in SKOV3 ovarian cancer cells was evaluated with a range of cytotoxicity assays. Parameters of cytotoxicity assessed in this study include metabolic function as measured with an MTT assay, oxidative stress as measured by a DCF assay, cell health as measured by a colony forming assay, and cell viability as measured by a neutral red assay. Morphological features of SKOV3 cells treated with each AuNP were also examined for characteristics of cell death. Results of these cytotoxicity and morphological evaluations suggest that AuNP-PEG induce apoptotic cell death, AuNP-TMAB induce oxidative stress that does not result in cell death, AuNP-DMAP induce autophagy cell death, and AuNP-COOH induce anoikis-apoptotic cell death. Future studies include further AuNP functionalization and the immunologic detection of components of cell death pathways.