Additionally, ST6Gal I has been observed to add sialylation in cell surface receptors, such as PDGFRB [44], EGFR [51,52], and PECAM [53], which increases protein levels and phosphorylation to stimulate pathways such as PI3K/AKT and RAS [43], thus contributing to tumor growth. The gene discussed is ST6GAL1; the disease is neoplasm.