Increased copy number variation in metastatic CRC cells
We have developed an immuno-competent mouse model of metastatic colorectal cancer by sequentially passaging small intestinal organoids with mutations in Apc, Kras, Tp53 and Smad4 in vivo. For this 1x10^4 AKPS organoids were injected into the colonic submucosa. These cells grew into a primary tumor and metastasized to the liver. When animals were sacrificed at the humane endpoint, the colon tumor and liver metastasis were harvested, dissociated into single cells and expanded in vitro. After the in vitro expansion, cells were then injected again into the colon of a new cohort of C57BL/6 mice. Organoids from the in vitro expansion step from either Passage 1 (P1, m4), Passage 2 (P2, m15) and Passage 5 (P5, m484) were used, and DNA isolated for whole exome sequencing.