DDB1 and head and neck squamous cell carcinoma: Most of the potential binding proteins of USP2-AS1 are listed in Figure 4B. Next, we analyzed the clinical significance of these proteins in the TCGA-HNSCC dataset and found that DCAF13 (DDB1- and CUL4-associated factor 13), a substrate receptor for the CUL4–DDB1 E3 ubiquitin–protein ligase complex [29], was also highly expressed (Figure 4C) and positively correlated with USP2-AS1 (Figure 4D): a higher level of DCAF13 predicted poorer prognosis (Figure 4E) in HNSCC patients.