Thiols and the chemoprevention of cancer.
Thiols such as glutathione interfere with the complex carcinogenic process. Under stress conditions, they scavenge harmful molecules: Glutathione conjugation of electrophilic carcinogens may prevent tumor initiation, and reduced thiols may defend against oxidative stress. Thus, associated chemopreventive strategies involve enhancement of antioxidant or conjugating capacity by increasing the levels of, particularly, glutathione through precursor application or synthesis stimulation and by inducing the corresponding enzymes. The antioxidant potential of thiols is, however, a part of a more general capacity to regulate redox status even in the absence of unequivocal stress conditions. Redox status controls the activities of various cellular signalling proteins through oxidation or reduction of particular sensor structures that are also mostly thiols. The development of feasible chemotherapeutic strategies on the basis of this complex system of redox-sensitive messenger proteins is a goal in ongoing and future research.
Huber
Wolfgang W
WW
Research Unit of Toxicology and Prevention, Division Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, Borschkegasse 8A, A-1090 Vienna, Austria. wolfgang.huber@meduniwien.ac.at
Parzefall
Wolfram
W
D000818:Animals; D016588:Anticarcinogenic Agents / Q000008:administration & dosage*; D000975:Antioxidants / Q000378:metabolism; D002273:Carcinogens / Q000378:metabolism; D003545:Cysteine / Q000737:chemistry / Q000378:metabolism; D016503:Drug Delivery Systems; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D009369:Neoplasms / Q000517:prevention & control*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D015398:Signal Transduction; D013438:Sulfhydryl Compounds / Q000378:metabolism*
D016588:Anticarcinogenic Agents; D000975:Antioxidants; D002273:Carcinogens; D013438:Sulfhydryl Compounds; D005978:Glutathione; D003545:Cysteine