ESR1 and esophageal squamous cell carcinoma: Additionally, ESR1, OTUD6B, USP2, and USP37 showed a positive correlation with risk scores, while USP22 exhibited a significant negative correlation with risk scores (r = -0.7, p < 0.0001, Figures 8B, D), suggesting a potential role for these genes in ESCC tumor progression and patient prognosis.