Thirdly, the diagnostic specificity of these markers, especially in the case of adhesion glycoproteins such as ICAM-1, VCAM-1, E-selectin, and P-selectin, may be limited due to their shedding and production in other disease conditions such as diabetes mellitus, atherosclerosis, breast cancer, and Sjögren’s syndrome [59–63]. This evidence concerns the gene CD226 and breast cancer.