Most studies have confirmed that aberrant O‐glycosylation mediated by the loss of functional Cosmc contributes to tumour progression and metastasis in a broad range of human cancers including CRC.4, 9, 18 Here we questioned whether the tumour‐promoting effects of Cosmc overexpression were also due to aberrant O‐glycosylation. The gene discussed is C1GALT1C1; the disease is neoplasm.