C1GALT1C1 and breast cancer: This was demonstrated in breast cancer (T47D) cells and pancreatic cancer cells (Capan-1), and the knockdown of Cosmc in the cells inhibited polysaccharide extension over Tn antigen, thereby increasing the susceptibility of both tumor cells to NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC) and cytotoxic T lymphocyte-mediated killing [130].