IHC and Spearman's rank correlation analysis showed that the expression of p‐EGFR (TYR1068) was positively correlated with DDAH1 expression in human NPC tissues, however, no significant correlation was found between EGFR and DDAH1 (Figure 5C,D; Figure S5, Supporting Information). This evidence concerns the gene EGFR and nasopharyngeal carcinoma.