Arsenic trioxide: impact on the growth and differentiation of cancer cells and possible use in cancer therapy

Arsenic trioxide (As₂O₃) has recently been identified as an effective drug in different types of cancer therapy. It is a useful pharmacological agent in acute promyelocytic leukemia (APL) treatment, especially the form that is resistant to conventional chemotherapy with all-trans retinoic acid (ATRA). What is more, laboratory data suggest that As₂O₃ is also active when it comes to several solid tumor cell lines. However, the mechanism of action is not fully understood. As₂O₃ in high doses triggers apoptosis, while in lower concentrations it induces partial differentiation. The As₂O₃ mechanism of action involves effects on mitochondrial transmembrane potential which lead to apoptosis. It also acts on the activity of JNK kinase, glutathione, caspases, NF-ĸB nuclear factor or pro- and antiapoptotic proteins. This publication presents the current knowledge about the influence of arsenic trioxide in cancer cells.