The glutathione S transferase (GST) family is a major part of cellular defense mechanisms against endogenous and exogenous substances, many of which have carcinogenic potential. Alteration in the expression level or structure of the glutathione-S-transferase (GST) enzymes may lead to inadequate detoxification of potential carcinogens and consequently contribute to cancer development. The GSTP1 gene is a member of the glutathione S-transferases (GSTs) family of proteins; it encodes a phase II metabolic enzyme that detoxifies reactive electrophilic intermediates. GSTP1 is expressed in normal tissues at variable levels in different cell types. It is frequently over-expressed in many human cancers and the expression increases with tumor progression and is associated with a more aggressive biology, poor patient survival, and resistance to therapy.
