Recent studies have shown that an important Trx binding protein, thioredoxin interacting protein [Txnip/thioredoxin binding protein-2 (TBP-2)/vitamin D3 upregulated protein (VDUP1)] has the reciprocal function with Trx in the pathogenesis of disease such as autoimmune disease, cancer, and diabetes (1–3). Here, TXN is linked to cancer.