Function and regulation of the human multidrug resistance gene.

The discovery of an energy-dependent pump system for natural product anticancer drugs has important implications for the biology of related energy-dependent transport systems as well as for the treatment of human cancer. To fully realize the therapeutic potential associated with manipulation of the multidrug transporter, it will be necessary to understand the mechanisms of action of the transporter and its mode of regulation. This review has summarized recent developments in these areas which suggest that both the activity of the pump and its genetic regulation are potential targets for new anticancer therapies.