RAD21 and cancer: On the other hand, the role of cohesins in preventing replication stress may account for the observation that Myc and RAD21 are frequently co-amplified in cancer (Supplementary Figure 7); here the intrinsic RS promoted by Myc deregulation may be restrained by the concomitant reinforcement of cohesin-mediated DNA synthesis, thus permitting faithful clonal expansion of tumor cells.