EXO1 and cancer: In summary, our research found that EXO1 was overexpressed in HCC and played a carcinogenic role in HCC, and that FOXP3 may upregulate the expression level of EXO1. For the first time, we have uncovered a possible transcriptional regulation mechanism of EXO1. This discovery provides clues for the relationship between DNA damage repair genes and HCC and might lead to the development of novel anti-cancer therapeutics for HCC treatment.