EGFR is a target of the tumor suppressor E3-ligase FBXW7
FBXW7 is and E3 ubiquitin ligase and is highly mutated in colorectal cancer. We used human colon organoids with engineered FBXW7 hotspot mutations to investigate novel targets of E3 ligase activity with a combined transcriptomic and proteomic approach uncovering the EGFR-MAPK pathway as highly regulated by the E3 ligase activity. Overall design: Human colon organoids were engineered to carry hotspot FBXW7 R505C mutation in combination or not with TP53 nonsense mutation with CRISPR-CAS9 Cytosine base editors. N=2 different clones with the same genetic background were passaged to single cells and seeded in BME with the same cell density. Cells were allowed to recover in full medium for 5 days before being washed and cultured for 48h in a medium depleted from EGF. The organoids were then recovered from BME and processed for RNA extraction and RNA-sequencing.