Frontiers in Bioscience-Landmark (FBL) is published by IMR Press from Volume 26 Issue 5 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on imrpress.com as a courtesy and upon agreement with Frontiers in Bioscience.
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Resistance to chemotherapy ('drug resistance') is a fundamental problem that limits the effectiveness of many chemotherapies currently used to treat cancer. Drug resistance can occur due to a variety of mechanisms, such as increased drug inactivation, drug efflux from cancer cells, enhanced repair of chemotherapy-induced damage, activation of pro-survival pathways and inactivation of cell death pathways. In this article, we review some of the major mechanisms of drug resistance and discuss how new molecularly-targeted therapies are being increasingly used to overcome these resistance mechanisms.