Glutathione S-transferase alpha 4 (GSTA4)

Glutathione S-transferase alpha 4 (GSTA4) is an enzyme of the alpha class of cytosolic glutathione S-transferases. It catalyzes the conjugation of reduced glutathione (GSH) to electrophilic and hydrophobic compounds, especially 4-hydroxynonenal (4-HNE), a highly reactive lipid peroxidation product, thereby facilitating detoxification and protection against oxidative stress. GSTA4 is expressed in several tissues and is involved in cellular defense against toxic, carcinogenic, and pharmacologically active electrophiles. Reduced GSTA4 expression is linked to increased vulnerability to oxidative injury and degenerative diseases (such as Alzheimer's, Parkinson's, and atherosclerosis), and its overexpression has been associated with chemoresistance and proliferation in cancer cells, notably colorectal cancer. GSTA4 also modulates apoptosis and differentiation in certain cell types, including oligodendrocytes.

Other names

Glutathione S-transferase A4GSTA4GSTA4-4GTA4GST class-alpha member 4Glutathione S-transferase A4-4glutathione S-alkyltransferase A4glutathione S-aralkyltransferase A4glutathione S-aryltransferase A4S-(hydroxyalkyl)glutathione lyase A4

Drugs increasing cytotoxic lipid peroxidation product accumulation (e.g., 4-hydroxynonenal) via inhibition of GSTA4, leading to increased apoptosis in tumor cells. Enhancement of chemotherapeutic efficacy by sensitizing cells to oxidative damage when GSTA4 is suppressed.