Hypoxic cells, which are a common feature of solid tumors, but not normal tissues, are resistant to both anticancer drugs and radiation therapy. Thus the identification of drugs with selective toxicity toward hypoxic cells is an important objective in anticancer chemotherapy. The benzotriazine di-N-oxide (SR 4233, Tirapazamine) has been shown to be an efficient and selective cytotoxin for hypoxic cells. Since the bioreductive activation of Tirapazamine ...
