SMAD4 and neoplasm: Concerning COADREAD (figure 6a), it appeared that the presence of a KRAS mutation in a tumour was not associated with AGR2 expression, whereas the presence of APC or TP53 mutation was negatively associated with AGR2 expression, and the presence of SMAD4, BRAF or PIK3CA mutation was positively associated with AGR2 expression.