We have previously reported that the expression of endoplasmic reticulum disulphide oxidase 1α (ERO1α), an oxidase localized in the endoplasmic reticulum that plays a role in the formation of disulphide bonds, is higher in various types of cancer when compared to normal tissues, and that the expression levels of this molecule are associated with cancer progression and prognosis [18–21]. This evidence concerns the gene ERO1A and cancer.