The reversal of antineoplastic drug resistance in cancer cells by β-elemene

Multidrug resistance(MDR), deined as the resistance of cancer cells to compounds with diverse structures and mechanisms of actions, signiicantly limits the eicacy of antitumor drugs. A major mechanism that mediates MDR in cancer is the overexpression of adenosine triphosphate(ATP)?binding cassette transporters. These transporters bind to their respective substrates and catalyze their elux from cancer cells, thereby lowering the intracellular concentra?tions of the substrates and thus attenuating or even abolishing their eicacy. In addition, cancer cells can become resistant to drugs via mechanisms that attenuate apoptosis and cell cycle arrest such as alterations in the p53, check point kinase, nuclear factor kappa B, and the p38 mitogen?activated protein kinase pathway. In this review, we discuss the mechanisms by which β?elemene, a compound extracted from Rhizoma zedoariae that has clinical antitumor eicacy, overcomes drug resistance in cancer.