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Quantitative
assessment of glioblastoma invasion in vivo
Pierre
D. Mourada,b,
Lindi Farrella,
Louis D. Stampsa,
Paul Santiagoa,
Helen L. Fillmorec,d, William C.
Broaddusc,d
and Daniel L. Silbergeld a
aDepartment of Neurological Surgery, University of Washington, Seattle, WA, USA.
bCenter for Industrial and Medical Ultrasound, Applied Physics
Laboratory, University of Washington, Seattle, WA, USA.
cDivision of Neurosurgery, Medical College of Virginia, Virginia
Commonwealth University and Neurosurgery Section, Richmond, VA, USA.
dResearch Service, Hunter Holmes McGuire Department of Veterans
Affairs Medical Center, Richmond, VA, USA. Received
15 August 2002; revised 30 October 2002; accepted 31 October 2002; Available
online 17 January 2003.
The aim of this study is the quantitative assessment of the time course and
spatial distribution in brain of invading glioblastoma (GBM) cells using a
recently described model consisting of RT2 rat GBM cells stably transfected with
enhanced green fluorescent protein (eGFP) – called RT2-eGFP – and implanted
in Fischer rats.
Invasion throughout the brain was verified by confocal microscopy and
immunocytochemical staining for eGFP.
Rats were sacrificed on post-implantation days 3, 8, and time of death (TOD).
First, the entire rat brain was disaggregated at each time point and viable
RT2-eGFP cells were counted using flow cytometry with fluorescence as the
marker. Next, 2 mm3 samples of cortex from each of four brain
quadrants (bifrontal and bioccipital) were disaggregated at each time point,
with tumor cell quantification as before.
Tumor cell density, averaged over the entire brain, reached a peak mid-way
through its time course, leveling out by TOD.
Tumor cell density within bulk tumor (BT) was greatest early in the evolution of
the brain tumor, decreasing to its final value mid-way through its time course,
due to necrosis.
The greatest concentration of tumor cells was within BT, with up to an order of
magnitude fewer cells in the periphery, while the number of brain tumor cells
invading brain distant from BT remained constant from day 3 until TOD.
BT size steadily increased after implantation, with an increasing portion due to
central necrosis as time progressed, suggesting that this effect is an important
contributor to fatality in this model.
Alternatively (or additionally), accumulation of toxins elaborated by tumor
cells throughout the brain starting early in the evolution of the tumor may also
contribute to fatality.
PMID: 12637158 [PubMed - indexed for MEDLINE]
Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12637158
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