We used Northern blot analysis to measure the expression of mRNA for platelet-derived growth factor subunit A (PDGF-A), PDGF-B and the PDGF-α receptor (PDGFR-α) and PDGF-β receptor (PDGFR-β) in ependymomas and medulloblastomas. We analyzed tissue from 5 patients for each tumor type, looking specifically for components of an autocrine or paracrine system in these tumors. PDGF-A was expressed in all tumors, PDGFR-α, which binds all 3 PDGF isoforms, was only found in ependymomas. Thus only ependymomas appeared to have a potential for using PDGFR-α autocrine loops. PDGF-B was expressed only in ependymomas, although the PDGFR-β was expressed in both medulloblastomas and ependymomas. Again, therefore, only ependymomas appear to have a potential autocrine loop with PDGFR-β. These data suggest that ependymomas have the biochemical prerequisites for autocrine and/or paracrine loops using PDGFR-α or PDGFR-β systems. In this they resemble other glial tumors such as anaplastic astrocytomas and glioblastomas. Medulloblastomas do not appear to have the ligand and/or receptor for either the PDGFR-α or PDGFR-β autocrine loop.

This content is only available via PDF.
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.
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 government 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.
You do not currently have access to this content.