Protecting p53 from degradation.
Inactivation of the p53 function is a common event in cancer. Approx. 50% of human tumours express mutant p53 and there is evidence that in others, including many childhood tumours, p53 function is impaired in other ways. These defects on p53 function may be due to the alteration of cellular factors that modulate p53 or to the expression of viral oncoproteins. Radiotherapy and many of the chemotherapeutic drugs currently used in cancer treatment are potent activators of p53. However, most of these therapies have a serious drawback; that is, the long-term consequences of their DNA-damaging effects. Understanding the mechanisms regulating p53 stability is crucial for the development of new strategies to activate p53 non-genotoxically. Here we describe the effect of a potent activator of the p53 response, the nuclear export inhibitor leptomycin B, on Mdm2 degradation and we provide evidence for the oligomerization of the p14ARF tumour suppressor and Mdm2 inhibitor in response to oxidative stress.
Laín
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Department of Surgery and Molecular Oncology, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, Scotland, U.K. s.lain@dundee.ac.uk
D000970:Antineoplastic Agents; D019281:Dimerization; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D006801:Humans; D018716:Molecular Mimicry; D009687:Nuclear Proteins; D018384:Oxidative Stress; D010446:Peptide Fragments / Q000494:pharmacology / Q000627:therapeutic use; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051736:Proto-Oncogene Proteins c-mdm2; D025803:Tumor Suppressor Protein p14ARF / Q000737:chemistry / Q000502:physiology; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D000970:Antineoplastic Agents; D005231:Fatty Acids, Unsaturated; D009687:Nuclear Proteins; D010446:Peptide Fragments; D011518:Proto-Oncogene Proteins; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; C038753:leptomycin B