NEDD8 and lip and oral cavity carcinoma: First, we performed a Spearman correlation test against the coexpression of NEDD8 with other somatic genes in TCGA oral cancer tissues derived from radiotherapy-receiving patients who were defined as low NEDD8 expression/cancer nonprogression and high NEDD8 expression/cancer progression in Kaplan‒Meier analysis (Fig. 1E).