To evaluate whether ST8Sia2 and ST8Sia4, PSA-NCAM, and UDP-E are affected by the pathological hallmark of AD, Aβ, we analyzed the protein and mRNA expression levels of NCAM, PSA-NCAM, ST8Sia4, ST8Sia2, and UDP-E in our cell model expressing the ST8 enzymes and PSA-NCAM simultaneously (IMR 32; ATCC, Manassas, VA). The gene discussed is PROS1; the disease is Alzheimer disease.