APEX1 and neoplasm: IHC scoring and clinicopathological data analysis showed that high expression of Ref-1 was positively correlated with BRAF mutation and lymph node metastasis (Table 1 and Fig. 1E) but not associated with patient sex, age, tumor diameter, number of lesions, T stage, or TNM stage (AJCC Eighth) and indicated that patients with negative Ref-1 staining had longer relapse-free survival than those with positive staining (Fig. 1F).