Gold nanoparticles have excellent properties for cancer therapeutics because their tunable size and surface chemistry make them customizable for many applications. For immunotherapy applications in particular, we can leverage their natural biodistribution to the spleen and immune cells for delivering peptide antigen vaccines or tune their optical properties for photothermal therapy to ablate tumors, which results in tumor antigen circulation and an in situ vaccination effect. Our group has demonstrated the potential of gold nanoparticles to elicit systemic, anti-tumor immunity through several iterations of particle design, characterization, and in vivo testing. However, most of the animal testing was done using a B16-OVA model, which is less clinically relevant due to the transgene antigen inserted for vaccination and tumor detection. My work builds upon the strong foundation of proof-of-concept vaccination strategies and examines the use of these gold nanoparticle platforms for cancer immunotherapy applications in a more clinically relevant tumor model. Though many hurdles remain for the first gold nanoparticles to reach FDA approval, this work demonstrates the progression of gold nanoparticle-enabled cancer immunotherapy toward that end and illustrates novel immunotherapeutic outcomes and combinations that may inform future progress toward identifying a clinically viable gold nanoparticle cancer immunotherapy strategy.