Article

Pituitary tumor transforming gene 1 regulates Aurora kinase A activity.

Department of Medicine, Cedars-Sinai Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90048, USA.
Oncogene (Impact Factor: 8.56). 08/2008; 27(49):6385-95. DOI: 10.1038/onc.2008.234
Source: PubMed

ABSTRACT Pituitary tumor transforming gene 1 (PTTG1), a transforming gene highly expressed in several cancers, is a mammalian securin protein regulating both G1/S and G2/M phases. Using protein array screening, we showed PTTG1 interacting with Aurora kinase A (Aurora-A), and confirmed the interaction using co-immunoprecipitation, His-tagged pull-down assays and intracellular immunofluorescence colocalization. PTTG1 transfection into HCT116 cells prevented Aurora-A T288 autophosphorylation, inhibited phosphorylation of the histone H3 Aurora-A substrate and resulted in abnormally condensed chromatin. PTTG1-null cell proliferation was more sensitive to Aurora-A knock down and to Aurora kinase Inhibitor III treatment. The results indicate that PTTG1 and Aurora-A interact to regulate cellular responses to anti-neoplastic drugs. PTTG1 knockdown is therefore a potential approach to improve the efficacy of tumor Aurora kinase inhibitors.

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