In the present study, we evaluated the use of gold nanoparticles with their distinctive properties to increase the sensitivity of breast cancer cells to oncolytic NDV, to enhance apoptosis induction, as well as being selectively toxic in cancer cells, and to induce apoptosis by activating caspase-9, the p53 protein, and various other proteins involved in apoptosis. The gene discussed is TP53; the disease is breast cancer.