Cargando…

The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib

Separase, an endopeptidase required for the separation of sister-chromatides in mitotic anaphase, triggers centriole disengagement during centrosome duplication. In cancer, separase is frequently overexpressed, pointing to a functional role as an aneuploidy promoter associated with centrosomal ampli...

Descripción completa

Detalles Bibliográficos
Autores principales: Haaß, Wiltrud, Stehle, Michael, Nittka, Stefanie, Giehl, Michelle, Schrotz-King, Petra, Fabarius, Alice, Hofmann, Wolf-Karsten, Seifarth, Wolfgang
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3411713/
https://www.ncbi.nlm.nih.gov/pubmed/22870341
http://dx.doi.org/10.1371/journal.pone.0042863
_version_ 1782239879181107200
author Haaß, Wiltrud
Stehle, Michael
Nittka, Stefanie
Giehl, Michelle
Schrotz-King, Petra
Fabarius, Alice
Hofmann, Wolf-Karsten
Seifarth, Wolfgang
author_facet Haaß, Wiltrud
Stehle, Michael
Nittka, Stefanie
Giehl, Michelle
Schrotz-King, Petra
Fabarius, Alice
Hofmann, Wolf-Karsten
Seifarth, Wolfgang
author_sort Haaß, Wiltrud
collection PubMed
description Separase, an endopeptidase required for the separation of sister-chromatides in mitotic anaphase, triggers centriole disengagement during centrosome duplication. In cancer, separase is frequently overexpressed, pointing to a functional role as an aneuploidy promoter associated with centrosomal amplification and genomic instability. Recently, we have shown that centrosomal amplification and subsequent chromosomal aberrations are a hallmark of chronic myeloid leukemia (CML), increasing from chronic phase (CP) toward blast crisis (BC). Moreover, a functional linkage of p210BCR-ABL tyrosine kinase activity with centrosomal amplification and clonal evolution has been established in long-term cell culture experiments. Unexpectedly, therapeutic doses of imatinib (IM) did not counteract; instead induced similar centrosomal alterations in vitro. We investigated the influence of IM and p210BCR-ABL on Separase as a potential driver of centrosomal amplification in CML. Short-term cell cultures of p210BCR-ABL-negative (NHDF, UROtsa, HL-60, U937), positive (K562, LAMA-84) and inducible (U937p210BCR-ABL/c6 (Tet-ON)) human cell lines were treated with therapeutic doses of IM and analyzed by qRT-PCR, Western blot analysis and quantitative Separase activity assays. Decreased Separase protein levels were observed in all cells treated with IM in a dose dependent manner. Accordingly, in all p210BCR-ABL-negative cell lines, decreased proteolytic activity of Separase was found. In contrast, p210BCR-ABL-positive cells showed increased Separase proteolytic activity. This activation of Separase was consistent with changes in the expression levels of Separase regulators (Separase phosphorylation at serine residue 1126, Securin, CyclinB1 and PP2A). Our data suggest that regulation of Separase in IM-treated BCR-ABL-positive cells occurs on both the protein expression and the proteolytic activity levels. Activation of Separase proteolytic activity exclusively in p210BCR-ABL-positive cells during IM treatment may act as a driving force for centrosomal amplification, contributing to genomic instability, clonal evolution and resistance in CML.
format Online
Article
Text
id pubmed-3411713
institution National Center for Biotechnology Information
language English
publishDate 2012
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-34117132012-08-06 The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib Haaß, Wiltrud Stehle, Michael Nittka, Stefanie Giehl, Michelle Schrotz-King, Petra Fabarius, Alice Hofmann, Wolf-Karsten Seifarth, Wolfgang PLoS One Research Article Separase, an endopeptidase required for the separation of sister-chromatides in mitotic anaphase, triggers centriole disengagement during centrosome duplication. In cancer, separase is frequently overexpressed, pointing to a functional role as an aneuploidy promoter associated with centrosomal amplification and genomic instability. Recently, we have shown that centrosomal amplification and subsequent chromosomal aberrations are a hallmark of chronic myeloid leukemia (CML), increasing from chronic phase (CP) toward blast crisis (BC). Moreover, a functional linkage of p210BCR-ABL tyrosine kinase activity with centrosomal amplification and clonal evolution has been established in long-term cell culture experiments. Unexpectedly, therapeutic doses of imatinib (IM) did not counteract; instead induced similar centrosomal alterations in vitro. We investigated the influence of IM and p210BCR-ABL on Separase as a potential driver of centrosomal amplification in CML. Short-term cell cultures of p210BCR-ABL-negative (NHDF, UROtsa, HL-60, U937), positive (K562, LAMA-84) and inducible (U937p210BCR-ABL/c6 (Tet-ON)) human cell lines were treated with therapeutic doses of IM and analyzed by qRT-PCR, Western blot analysis and quantitative Separase activity assays. Decreased Separase protein levels were observed in all cells treated with IM in a dose dependent manner. Accordingly, in all p210BCR-ABL-negative cell lines, decreased proteolytic activity of Separase was found. In contrast, p210BCR-ABL-positive cells showed increased Separase proteolytic activity. This activation of Separase was consistent with changes in the expression levels of Separase regulators (Separase phosphorylation at serine residue 1126, Securin, CyclinB1 and PP2A). Our data suggest that regulation of Separase in IM-treated BCR-ABL-positive cells occurs on both the protein expression and the proteolytic activity levels. Activation of Separase proteolytic activity exclusively in p210BCR-ABL-positive cells during IM treatment may act as a driving force for centrosomal amplification, contributing to genomic instability, clonal evolution and resistance in CML. Public Library of Science 2012-08-03 /pmc/articles/PMC3411713/ /pubmed/22870341 http://dx.doi.org/10.1371/journal.pone.0042863 Text en © 2012 Haaß et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Haaß, Wiltrud
Stehle, Michael
Nittka, Stefanie
Giehl, Michelle
Schrotz-King, Petra
Fabarius, Alice
Hofmann, Wolf-Karsten
Seifarth, Wolfgang
The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title_full The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title_fullStr The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title_full_unstemmed The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title_short The Proteolytic Activity of Separase in BCR-ABL-Positive Cells Is Increased by Imatinib
title_sort proteolytic activity of separase in bcr-abl-positive cells is increased by imatinib
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3411713/
https://www.ncbi.nlm.nih.gov/pubmed/22870341
http://dx.doi.org/10.1371/journal.pone.0042863
work_keys_str_mv AT haaßwiltrud theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT stehlemichael theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT nittkastefanie theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT giehlmichelle theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT schrotzkingpetra theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT fabariusalice theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT hofmannwolfkarsten theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT seifarthwolfgang theproteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT haaßwiltrud proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT stehlemichael proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT nittkastefanie proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT giehlmichelle proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT schrotzkingpetra proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT fabariusalice proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT hofmannwolfkarsten proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib
AT seifarthwolfgang proteolyticactivityofseparaseinbcrablpositivecellsisincreasedbyimatinib