Send to

Choose Destination
See comment in PubMed Commons below
J Natl Cancer Inst. 1988 Mar 2;80(1):14-20.

Multidrug resistance.

Author information

Clinical Pharmacology Branch, National Cancer Institute, Bethesda, MD 20892.


The ability of malignant cells to develop resistance to cytotoxic drugs poses a major obstacle to the ultimate success of cancer therapy. While some mechanisms of resistance allow cells to survive exposure to a single agent, the phenomenon of multidrug resistance (MDR) confers upon cells the ability to withstand exposure to lethal doses of many structurally unrelated antineoplastic agents. MDR has been strongly linked to the overexpression of a membrane-associated glycoprotein, P-glycoprotein, which appears to play a role in drug efflux. However, several lines of evidence suggest that other mechanisms of resistance are involved in MDR; biochemical similarities observed in a human breast cancer cell line after the acquisition of MDR and in carcinogen-induced rat preneoplastic hepatic nodules indicate that changes in regulation of phase I and phase II drug-metabolizing enzymes may also play a role in MDR. An atypical pattern of MDR has been characterized and related to altered topoisomerase activity. Improvement in current cancer chemotherapy may be achieved by interfering with the regulation and expression of mechanisms of MDR.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Loading ...
    Support Center