KRAS and cancer: To test whether the drug combination was synergistic in other aggressive colorectal cancer subtypes, we evaluated it on a panel of organoids derived from liver, peritoneal, and lymph node metastases; pretreated vs. chemoradiation-naïve tumours; microsatellite unstable tumours; cancers of consensus molecular subtype 4 (CMS4); and KRAS- and BRAF-mutated tumours (Fig. 5a).