In vivo, CRISPR-based cancer therapies involve direct gene editing within living organisms to target oncogenes (e.g., KRAS, c-Myc, Figure 5B) and tumor suppressor genes (e.g., p53), as well as to modulate immune cells such as T cells and NK cells, offering the potential to target and modify cancer within the body directly. This evidence concerns the gene TP53 and cancer.