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Targeting the ubiquitin-mediated proteasome degradation of p53 for cancer therapy.

Department of Molecular & Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239. .
Current pharmaceutical design (Impact Factor: 3.29). 11/2012; DOI: 10.2174/1381612811319180009
Source: PubMed

ABSTRACT Within the past decade, there has been a revolution in the types of drugs developed to treat cancer. Therapies that selectively target cancer-specific aberrations, such as kinase inhibitors, have made a dramatic impact on a subset of patients. In spite of these successes, there is still a dearth of treatment options for the vast majority of patients. Therefore, there is a need to design therapies with broader efficacy. The p53 tumor suppressor pathway is one of the most frequently altered in human cancers. However, about half of all cancers retain wild-type p53, yet through various mechanisms, the p53 pathway is otherwiseinactivated. Targeting this pathway forreactivation truly represents the "holy grail" in cancer treatment. Most commonly, destabilization of p53 by various components of ubiquitin-proteasome system, notably the ubiquitin ligase MDM2 and its partner MDMX as well as various deubiquitinating enzymes (DUBs), render p53 inert and unresponsive to stress signals. Reinstating its function in cancer has been a long sought-after goal. Towards this end, a great deal of work has been devoted to the development of compounds thateither interfere with the p53-MDM2 and p53-MDMX interactions, inhibit MDM2 E3 activity, or target individual DUBs. Here we review the current progress that has been made in the field, with a special emphasis on both MDM2 and DUB inhibitors. Developing inhibitors targeting the upstream of the p53 ubiquitination pathway will likely also be a valuable option.

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Available from: Mu-Shui Dai, Jun 17, 2015
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