IGFBP3 and esophageal squamous cell carcinoma: In the CSNK2A1 high-expression group, we noted several highly expressed proteins that have been previously implicated (34, 51–53) in ESCC development, including IGFBP3 (Wilcoxon test, P = 0.014), LAMC2 (Wilcoxon test, P = 0.0042), MAGEA4 (Wilcoxon test, P = 0.05), and SLC7A5 (Wilcoxon test, P = 7.9 × 10–4) (Supplemental Figure 7C).