One of the most promising applications of CRISPR-Cas9 in cancer therapy is the possibility of directly targeting and correcting genetic mutations that cause cancer. For example, researchers are exploring ways to use CRISPR-Cas9 to repair mutations in the TP53 gene, a common mutation in various cancers. Additionally, CRISPR-Cas9 can be used to enhance the immune system's ability to fight cancer by editing immune cells to better recognize and attack cancer cells.