RXRA and head and neck squamous cell carcinoma: In addition to well-known degron-mutation enriched proteins such as CTNNB1, NFE2L2, and EPAS1 [11, 20], we also identified several proteins rich in degron-mutations that have not been revealed before, such as RXRA in bladder urothelial carcinoma (BLCA), CRNKL1 in skin cutaneous melanoma (SKCM), VPS13D in head and neck squamous cell carcinoma (HNSC), and CIC in LGG.