It plays an essential role in Okazaki fragment maturation of DNA replication, and is an important component in DNA repair pathways such as base excision repair (BER) and polymerase α error editing (AEE) pathway.19, 20, 21, 22 FEN1 is reported to be overexpressed in many forms of cancer, and FEN1 inhibitor has been reported to enhance the effect of DNA damage‐related chemotherapy drugs such as cisplatin, 5‐FU, and paclitaxel.18, 23, 24, 25. The gene discussed is FEN1; the disease is cancer.