APEX1 and cancer: Besides these two types of cancer, abnormal expression of APEX1 in both mRNA and protein levels have been found in other cancers, such as breast cancer11, gastric cancer12, ovarian serous cancer13, bladder cancer14, colon cancer15, prostate cancer16, osteosarcoma cancer17, melanoma18, etc. Overexpression (OE) of APEX1 in melanoma was clearly observed by both Yang et al.18 as well as Figi et al.19, showing that APEX1 might involve in the development of melanoma.