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30, No. 3, 2012
Issue release date: August 2012
Cell Physiol Biochem 2012;30:512-522
(DOI:10.1159/000341434)

Sunitinib-sensitive Suicidal Erythrocyte Death

Shaik N. · Lupescu A. · Lang F.
Department of Physiology, University of Tuebingen, Tuebingen
email Corresponding Author

Abstract

Sunitinib, a multikinase inhibitor, stimulates apoptosis and is thus utilized for the treatment of malignancy. Even though lacking mitochondria and nuclei, critical elements in apoptosis of nucleated cells, erythrocytes may undergo eryptosis, an apoptosis-like suicidal death, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserineexposure at the cell surface. Triggers of eryptosis include activation of Ca2+ permeable cation channels with subsequent increase of cytosolic Ca2+-activity ([Ca2+]i), ceramide formation, ATP-depletion, stimulation of p38 kinase and caspase activation. The present study explored, whether sunitinib stimulates eryptosis. [Ca2+]i was estimated from Fluo-3-fluorescence, cell volume from forward scatter, phosphatidylserine-exposure from annexin-V-binding, hemolysis from hemoglobin release, ceramide abundance from anti-ceramide antibody binding, and cytosolic ATP from luciferin–luciferase activity. A 48 h exposure to sunitinib (10 µM) significantly decreased forward scatter and increased annexin-V-binding, effects paralleled by significant increase of [Ca2+]i. Sunitinib exposure was followed by a slight but significant increase of hemolysis. Sunitinib induced annexin-V-binding was slightly, but significantly blunted by removal of extracellular Ca2+, by p38 kinase inhibitor SB203580 (10 µM) and by the pancaspase inhibitor zVAD (10 µM). Sunitinib, however, did not significantly modify cytosolic ATP and ceramide abundance. The present observations reveal that sunitinib is able to trigger suicidal death in erythrocytes even in the absence of nuclei and mitochondria.


 Outline


 goto top of outline Key Words

  • Phosphatidylserine
  • Sunitinib
  • Ca2+
  • Cell volume
  • Eryptosis
  • Red blood cells
  • Erythrocytes

 goto top of outline Abstract

Sunitinib, a multikinase inhibitor, stimulates apoptosis and is thus utilized for the treatment of malignancy. Even though lacking mitochondria and nuclei, critical elements in apoptosis of nucleated cells, erythrocytes may undergo eryptosis, an apoptosis-like suicidal death, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserineexposure at the cell surface. Triggers of eryptosis include activation of Ca2+ permeable cation channels with subsequent increase of cytosolic Ca2+-activity ([Ca2+]i), ceramide formation, ATP-depletion, stimulation of p38 kinase and caspase activation. The present study explored, whether sunitinib stimulates eryptosis. [Ca2+]i was estimated from Fluo-3-fluorescence, cell volume from forward scatter, phosphatidylserine-exposure from annexin-V-binding, hemolysis from hemoglobin release, ceramide abundance from anti-ceramide antibody binding, and cytosolic ATP from luciferin–luciferase activity. A 48 h exposure to sunitinib (10 µM) significantly decreased forward scatter and increased annexin-V-binding, effects paralleled by significant increase of [Ca2+]i. Sunitinib exposure was followed by a slight but significant increase of hemolysis. Sunitinib induced annexin-V-binding was slightly, but significantly blunted by removal of extracellular Ca2+, by p38 kinase inhibitor SB203580 (10 µM) and by the pancaspase inhibitor zVAD (10 µM). Sunitinib, however, did not significantly modify cytosolic ATP and ceramide abundance. The present observations reveal that sunitinib is able to trigger suicidal death in erythrocytes even in the absence of nuclei and mitochondria.

Copyright © 2012 S. Karger AG, Basel


 goto top of outline Author Contacts

Prof. Dr. Florian Lang
Physiologisches Institut, der Universität Tübingen
Gmelinstr. 5, D-72076 Tübingen (Germany)
Tel. +49 7071 29 72194, Fax +49 7071 29 5618
E-Mail florian.lang@uni-tuebingen.de


 goto top of outline Article Information

Accepted: June 12, 2012
Published online: July 19, 2012
Number of Print Pages : 11


 goto top of outline Publication Details

Cellular Physiology and Biochemistry (International Journal of Experimental Cellular Physiology, Biochemistry and Pharmacology)

Vol. 30, No. 3, Year 2012 (Cover Date: August 2012)

Journal Editor: Guggino W. (Baltimore, Md.), Lang F. (Tübingen)
ISSN: 1015-8987 (Print), eISSN: 1421-9778 (Online)

For additional information: http://www.karger.com/CPB


Copyright / Drug Dosage / Disclaimer

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

Abstract

Sunitinib, a multikinase inhibitor, stimulates apoptosis and is thus utilized for the treatment of malignancy. Even though lacking mitochondria and nuclei, critical elements in apoptosis of nucleated cells, erythrocytes may undergo eryptosis, an apoptosis-like suicidal death, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserineexposure at the cell surface. Triggers of eryptosis include activation of Ca2+ permeable cation channels with subsequent increase of cytosolic Ca2+-activity ([Ca2+]i), ceramide formation, ATP-depletion, stimulation of p38 kinase and caspase activation. The present study explored, whether sunitinib stimulates eryptosis. [Ca2+]i was estimated from Fluo-3-fluorescence, cell volume from forward scatter, phosphatidylserine-exposure from annexin-V-binding, hemolysis from hemoglobin release, ceramide abundance from anti-ceramide antibody binding, and cytosolic ATP from luciferin–luciferase activity. A 48 h exposure to sunitinib (10 µM) significantly decreased forward scatter and increased annexin-V-binding, effects paralleled by significant increase of [Ca2+]i. Sunitinib exposure was followed by a slight but significant increase of hemolysis. Sunitinib induced annexin-V-binding was slightly, but significantly blunted by removal of extracellular Ca2+, by p38 kinase inhibitor SB203580 (10 µM) and by the pancaspase inhibitor zVAD (10 µM). Sunitinib, however, did not significantly modify cytosolic ATP and ceramide abundance. The present observations reveal that sunitinib is able to trigger suicidal death in erythrocytes even in the absence of nuclei and mitochondria.



 goto top of outline Author Contacts

Prof. Dr. Florian Lang
Physiologisches Institut, der Universität Tübingen
Gmelinstr. 5, D-72076 Tübingen (Germany)
Tel. +49 7071 29 72194, Fax +49 7071 29 5618
E-Mail florian.lang@uni-tuebingen.de


 goto top of outline Article Information

Accepted: June 12, 2012
Published online: July 19, 2012
Number of Print Pages : 11


 goto top of outline Publication Details

Cellular Physiology and Biochemistry (International Journal of Experimental Cellular Physiology, Biochemistry and Pharmacology)

Vol. 30, No. 3, Year 2012 (Cover Date: August 2012)

Journal Editor: Guggino W. (Baltimore, Md.), Lang F. (Tübingen)
ISSN: 1015-8987 (Print), eISSN: 1421-9778 (Online)

For additional information: http://www.karger.com/CPB


Copyright / Drug Dosage

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.