Among the genes whose expression was upregulated in NPCs of Ring1B KO mice, pathway analysis revealed an enrichment of categories such as pathways in cancer and extracellular matrix (ECM)–receptor interaction (Fig. 4d), with this enrichment being due, at least in part, to derepression of protocadherin-γ and collagen family genes (Supplementary Data 1). This evidence concerns the gene RNF2 and cancer.