For example, organoid models for colon cancer were constructed in vitro by using CRISPR to introduce mutations in tumor-suppressorgenes (APC, TP53, SMAD4, etc.)and modify oncogenes (KRAS, PI3K, etc.). Roper et al. established a protocol to induce site-directed tumors rapidlyand efficiently in the distal colon of mice by utilizing colonoscopy-guidedmucosal injection. Here, TP53 is linked to neoplasm.