Trends in the Exploration of Anticancer Targets and Strategies in Enhancing the Efficacy of Drug Targeting

Department of Pharmacy, National University of Singapore, Singapore.
Current Molecular Pharmacology 11/2008; 1(3):213-32. DOI: 10.2174/1874-470210801030213
Source: PubMed


A number of therapeutic targets have been explored for developing anticancer drugs. Continuous efforts have been directed at the discovery of new targets as well as the improvement of therapeutic efficacy of agents directed at explored targets. There are 84 and 488 targets of marketed and investigational drugs for the treatment of cancer or cancer related illness. Analysis of these targets, particularly those of drugs in clinical trials and US patents, provides useful information and perspectives about the trends, strategies and progresses in targeting key cancer-related processes and in overcoming the difficulties in developing efficacious drugs against these targets. The efficacy of anticancer drugs directed at these targets is frequently compromised by counteractive molecular interactions and network crosstalk, negative and adverse secondary effects of drugs, and undesired ADMET profiles. Multi-component therapies directed at multiple targets and improved drug targeting methods are being explored for alleviating these efficacy-reducing processes. Investigation of the modes of actions of these combinations and targeting methods offers clues to aid the development of more effective anticancer therapies.

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    • "Even with this success, the clinical reality is that cancer persists, and even recurs within the same patient, due to tumor heterogeneity, which leads to an attenuated response to an individual anti-cancer therapy. Thus it is necessary to develop agents that do not target just one pathway, but instead, concurrently target several cancer pathways without toxicity toward healthy tissues (Zhu et al., 2008). COG112 showed selective proliferation inhibition for aggressive cancer cells but did not affect normal fibroblasts (Figure 3E), suggesting that COG112 may fulfill these ideal requirements. "
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