Mini review Jasmonates in cancer therapy

Several groups have reported in recent years that members of the plant stress hormones family of jasmonates, and some of their synthetic derivatives, exhibit anti-cancer activity in vitro and in vivo. Jasmonates increased the life span of EL-4 lymphomabearing mice, and exhibited selective cytotoxicity towards cancer cells while sparing normal blood lymphocytes, even when the latter were part of a mixed population of leukemic and normal cells drawn from the blood of chronic lymphocytic leukemia (CLL) patients. Jasmonates join a growing number of old and new cancer chemotherapeutic compounds of plant origin. Three mechanisms of action have been proposed to explain the anti-cancer activity of jasmonates. These include: (1) The bio-energetic mechanism-jasmonates induce severe ATP depletion in cancer cells via mitochondrial perturbation; (2) The re-differentiation mechanism-jasmonates induce re-differentiation in human myeloid leukemia cells via mitogen-activated protein kinase (MAPK) activity; (3) The reactive oxygen species (ROS)-mediated mechanism-jasmonates induce apoptosis in lung carcinoma cells via the generation of hydrogen peroxide, and pro-apoptotic proteins of the Bcl-2 family. Several similarities between the effects of jasmonates on plant and cancer cells have been recorded, suggesting that additional analysis of jasmonate effects in plant cells may contribute to a deeper understanding of the anti-cancer actions of these compounds. Those similarities include: induction of cell death, suppression of proliferation and cell cycle arrest, MAPK induction, ROS generation, and enhancement of heat-shock proteins (HSP) expression. Finally, jasmonates can induce death in drug-resistant cells. The drug resistance was conferred by either p53 mutation or P-glycoprotein (P-gp) over-expression. In summary, the jasmonate family of novel anti-cancer agents presents new hope for the development of cancer therapeutics, which should attract further scientific and pharmaceutical interest. q 2006 Elsevier Ireland Ltd. All rights reserved.