Biomedical Applications of GST

Whereas the GST were studied originally because of their involvement in mercapturic acid biosynthesis, these enzymes are also currently of interest to researchers working in fields other than toxicology. Some of the research areas in which GST are of importance include tumor markers, inherited cancer susceptibility, drug resistance, biotechnology, and clinical biochemistry. 

The pi-class enzyme is not the only GST that can serve as a tumor marker. A 

GST-mediated drug resistance can be overcome by treatment with chemicals that are (1) inhibitors of GST activity, (2) GST substrates, or (3) agents that deplete intracellular GSH. The inhibitors piriprost, indomethacin, and gossypol (Fig. 16) 

Association between Polymorphic Expression of GST and Susceptibility to Toxic Chemicals 

Failure to express GST can have a pronounced effect on the sensitivity of cells to chemical insult. In humans, one of the mu-class GST genes, GST Ml, is absent in approximately 45% of the population (B29, B30, S41). A characteristic feature of the enzyme encoded at this locus is its high conjugating activity toward certain 

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