It is reported that in a colorectal cancer study that Naïve Tregs (CD3+CD4+FOXP3lowCD45RA+) and effector Tregs (CD3+CD4+OXP3highCD45RA−) have immunosuppressive activity whereas non-Tregs (CD3+CD4+FOXP3lowCD45RA−) have antitumour activity (34). Here, CD4 is linked to colorectal cancer.