Though our results mentioned above have firstly suggested an interaction between Mus81 and CHK1 in human HCC cells, a previous study has actually identified an interplay between Mus81 activity at stalled forks and the CHK1‐dependent DNA damage checkpoint during S phase when replication forks have collapsed in Schizosaccharomyces pombe31. Here, CHEK1 is linked to hepatocellular carcinoma.