To test if upregulation of GCNT1 alters the cell surface glycosylation of prostate cancer cells, we monitored the recognition by lectins and glycan-binding antibodies in PC3 prostate cancer cells overexpressing GCNT1 (PC3 cells were chosen for these experiments as they have low levels of endogenous GCNT1 expression, Supplementary Fig. 1). The gene discussed is GCNT1; the disease is prostate carcinoma.