APC and colorectal carcinoma: To demonstrate that the introduction of a novel KRAS mutation can lead to the type of downregulation of stromal and ECM genes that we have observed in our LARC patients, we used a GEMM of CRC whereby Apc can be conditionally suppressed using a doxycycline‐regulated shRNA and mutant Kras (G12D) is activated under a Cre recombinase [28] (Fig. 3A).