ABSTRACT
Cancer is an important lifestyle-related disease. An accumulation of changes in DNA is one cause of cancer. Environmental stressors such as infection, food additives, chemicals, and diesel exhaust particles cause various harmful changes, including DNA damage, leading to carcinogenesis (Figure 3.1). The host has multiple mechanisms to combat the effects of environmental stress, including immune responses, apoptosis, cell cycle control, and the induction of antioxidative enzymes. Thioredoxin is a vital component of the thiol-reducing system. The components of the thioredoxin system play important roles in protecting against oxidative stress. Expression of the thioredoxin gene is induced through the antioxidant responsive element (ARE) by Nrf2. Thioredoxin inducers may be useful for cancer prevention by reducing oxidative and DNA damage. We have identified thioredoxin-binding protein-2/vitamin-D3-upregulated protein 1 (TBP-2/VDUP1). We and others have shown that the expression of TBP-2 is lost in cancer cell lines and cancerous tissues, and ectopic overexpression of TBP-2 results in growth suppression. Thus, TBP-2 seems to play a role as an apparent suppressor oncogene. Use of the TBP-2 system may be another novel approach to cancer suppression.
