the cisplatin induced re-distribution approach could be confirmed by checking strong GFP fluorescence in WT MEFs revealing GFP nucleolin. Though in untreated MEFs, GFP nucleolin was Icotinib limited to the nucleus and only several cells showed a cytosolic GFP in response to cisplatin, 70-300 of the GFP nucleolin expressing cells showed a cytosolic GFP. Assessment of the redistribution of yet another nuclear protein, KAP 1, revealed that KAP 1 didn’t alter its localization in a reaction to cisplatin or camptothecin, therefore suggesting that pressure induces the redistribution for many, but not all, nuclear proteins. Next, we completed a period course examination of nuclear protein redistribution in cisplatin and camptothecin treated WT MEFs. In response to cisplatin, the redistribution of H1, NPM and nucleolin already began at 2 h, plateaued at 6 9 h and then further increased to optimum values by 24 h. In contrast, very little KAP 1 redistribution was observed at 2 9 h and only 11.25-inch was observed at 24 h. It’s remarkable that at 6 9 h of cisplatin therapy, when about 30 % of cells exhibited nuclear protein redistribution, very few cells exhibited apoptotic features, such as for instance Bax or Bak NT exposure, caspase 3 activation, cytochrome c release, apoptotic Papillary thyroid cancer nuclei or His GFP annexin V exposure. Comparable effects were obtained when WT MEFs were treated with camptothecin. To exclude the chance that these results were biased toward the WT MEF cell clone used, we examined nuclear protein redistribution and apoptotic characteristics in a WT MEF cell line isolated independently. Cisplatin induced a time dependent nuclear protein redistribution in WT1 MEFs, resembling that in WT MEFs, although with reasonable differences and also preceded the appearance of apoptotic events, as shown in Figure 2a. Collectively, these results suggest that the redistribution of H1, natural compound library NPM and nucleolin shows an early stress response that occurred before Bax/Bak activation, cytochrome c release and caspase 3 activation. Next, we examined the role of the apoptosome and caspases in stress-induced nuclear protein redistribution. First, we addressed Apaf 1 MEFs with cisplatin, camptothecin, doxorubicin or staurosporine, as described above. As shown in Supplementary Figure and previously reported23 S1b, Apaf 1 MEFs were observed to be resistant to apoptosis induced by these drugs. However, despite this resistance, the stress induced redistribution of nucleolin, NPM and H1 wasn’t affected by Apaf 1 deficiency. Quantification of nuclear protein redistribution in WT and Apaf 1 MEFs unveiled that the proportions of cells showing this influence after 24 h of drug treatment were similar in both genotypes for all three nuclear proteins, although basal levels of redistribution were raised in Apaf 1 cells, especially for NPM. To guide our knowledge, we also considered the process in caspase 9 MEFs.