Intrinsic resistance to anticancer drugs, or resistance developed during chemotherapy,
remains a major obstacle to successful treatment. This is the case both for resistance to
cytotoxic agents, directed at malignant cells, and for resistance to anti-angiogenic agents,
directed at non-malignant endothelial cells. In this review, we will discuss mechanisms of
resistance which have a bearing on both these conceptually different classes of drugs. The
complexity of drug resistance, involving drug transporters, such as P-glycoprotein, as well as …