Thus, the aim of this study was to evaluate the relationship between circulating levels of PCSK9 and circulating EPCs as assessed by the number of CD45neg/CD34bright (total EPC compartment), CD45neg/CD34bright/CD146neg (early EPC) and CD45neg/CD34bright/CD309pos (late EPC) and on CEC, as reflected by CD45neg/CD34bright/CD146pos, and their mutual relationship, in patients at risk of CV disease, with or without T2DM. The gene discussed is PCSK9; the disease is type 2 diabetes mellitus.