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Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c
07:42

Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c

Published on: June 29, 2011

Coexpression of genes involved in apoptosis in central nervous system neoplasms

C S Bruggers1, D Fults, S L Perkins

  • 1Department of Pediatrics, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, USA.

Journal of Pediatric Hematology/Oncology
|February 25, 1999
PubMed
Abstract

Insights

Brain tumors show coexpression of genes that promote and inhibit apoptosis. The balance between these genes influences the cell death threshold, impacting treatment response.

Area of Science:

  • Molecular Biology
  • Oncology
  • Neuroscience

Background:

  • Apoptosis is vital for development and cancer therapy.
  • Understanding apoptotic gene expression in brain tumors is critical.

Purpose of the Study:

  • Investigate apoptotic gene expression patterns in brain tumor tissues and cell lines.
  • Analyze the expression of BCL2, BCLXL, BCLXS, and BAX.

Main Methods:

  • Reverse transcriptase polymerase chain reaction (RT-PCR) for gene transcripts.
  • Immunohistochemical staining for protein expression.
  • Analysis of high-grade gliomas, ependymomas, glioblastomas, medulloblastomas, PNET, LGGs, and HGGs.

Main Results:

  • BCLXL and BAX were widely expressed in most brain tumors and cell lines.
  • BCL2 expression was limited to a single PNET cell line; absent in glial tumors.
  • BAX and BCLX protein levels were similar in low-grade and high-grade gliomas; p53 was elevated in some glioblastomas.

Conclusions:

  • Coexpression of proapoptotic and antiapoptotic genes is common in human brain tumors.
  • The relative balance of competing apoptotic genes likely dictates the apoptotic threshold.

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