Our finding that the O-linked glycosylating enzyme ST6GalNAc1 is androgen-regulated provides further evidence for a direct link between the AR and the glycoproteome in prostate cancer cells, and also suggests that it will be important to understand how these changes function co-ordinately rather than in isolation to modify the cellular behaviour of cancer cells. This evidence concerns the gene ST6GALNAC1 and Familial prostate cancer.