Overexpression of EVI1 interferes with cytokinesis and leads to accumulation of cells with supernumerary centrosomes in G0/1phase
Citations Over TimeTop 18% of 2012 papers
Abstract
Ectopic viral integration site 1 (EVI1), a transcription factor frequently overexpressed in myeloid neoplasias, has been implicated in the generation of malignancy-associated centrosomal aberrations and chromosomal instability. Here, we sought to investigate the underlying cause of centrosome amplification in EVI1-overexpressing cells. We found that overexpression of EVI1-HA in U2OS cells induced supernumerary centrosomes, which were consistently associated with enlarged nuclei or binuclear cells. Live cell imaging experiments identified cytokinesis failure as the underlying cause of this phenotype. In accordance with previous reports, EVI1 overexpression induced a partial cell cycle arrest in G0/1 phase, accompanied by elevated cyclin D1 and p21 levels, reduced Cdk2 activity and activation of the p53 pathway. Supernumerary centrosomes predominantly occurred in resting cells, as identified by low levels of the proliferation marker Ki-67, leading to the conclusion that they result from tetraploidization after cytokinesis failure and are confined to G0/1-arrested tetraploid cells. Depletion of p53 using siRNA revealed that further polyploidization of these cells was inhibited by the p53-dependent tetraploidy checkpoint.
Related Papers
- → Centrosome amplification drives chromosomal instability in breast tumor development(2002)566 cited
- → Correlation between centrosome abnormalities and chromosomal instability in human pancreatic cancer cells(2001)99 cited
- → Never tear us apart – the importance of centrosome clustering(2012)87 cited
- → The centrosome and cell proliferation.(2006)32 cited
- → Excessive centrosome abnormalities without ongoing numerical chromosome instability in a Burkitt's lymphoma.(2003)32 cited