Although colonic mucin production requires ER facilitation (64), both colorectal cancer mucinous adenocarcinoma and adenocarcinoma not otherwise specified showed markedly higher ER13 scores than normal tissue (Fig. 1B), suggesting that increased mucin production is not a major driver of ATF6 activity in colorectal cancer. This evidence concerns the gene MUC5AC and colon mucinous adenocarcinoma.