ST6GALNAC1 and neoplasm: ,82 However, their presence in tumor cells is difficult to predict based only on transcriptomic analysis as it can be influenced by multiple factors: activity or defects of the extending enzymes (C1GALT1 and ST6GALNAC1) or the COSMC chaperone (C1GALT1C1), overexpression of carriers (such as mucins), and GALNT re-localization to the endoplasmic reticulum.83