NFE2L2 and differentiated thyroid carcinoma: In papillary thyroid carcinoma (PTC), the most common thyroidal malignancy, immunohistochemical analysis showed that the protein levels of Nrf2 and Nqo1 were higher in carcinoma tissues compared to benign follicular adenomas and hyperplastic nodules; both proteins were undetectable in normal thyroid parenchyma adjacent to the PTC samples (42).