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[67]
In this context, cancer stem cells isolated from SVZ than HGG cells identified by CD44. [68]
could be used for drug screening to develop new
therapeutic strategies aimed at understanding their At the same time, other questions need to be addressed:
mechanisms of resistance [Figure 2]. Targeting the (1) what is the role of the other well characterized
SVZ will require extensive characterization of the neurogenic region in the adult brain (i.e. the SGZ); could
phenotype(s) of these cells as well as their studies to this be also source of neural precursors responsible for
assess the response to radiation. Interestingly, it has initiate HGG and other brain tumors in patients? (2)
been shown that irradiation of the SVZ in HGG patients what are the evolutionary trajectories in those patients
improves progression-free survival. [62] where the HGG lies in the cortical mantle and does not
show any contact with the SVZ by using FGMS? We
The involvement of the SVZ in HGG also prompt to the have just started to scratch the surface of what seems
need of classifying tumors according to their location in to be a complicated dynamic process of HGG evolution
the brain and integrating these data with molecular and that involves the SVZ, in addition to more recent
[69]
phenotypic analysis and clinical information [Figure 2]. publications by us and others deciphering the
[70]
A previous work showed that HGG involving the SVZ genomic architecture of the T. There is hope that these
give rise to recurrences far from the primary tumor site, findings and more studies on the role of SVZ in brain
contributing to the hypothesis that this is due to migrating tumors might impact on improving patient survival and
[63]
neural precursors. However, another study suggested leading to personalized treatments.
that there is no evidence of a “stem cell signature” in
HGG with involvement of SVZ in comparison to those Acknowledgments
with no involvement of this region. This might be The author is grateful to Mr. M. Locatelli for support and
[64]
reconciled considering that, as suggested by animal encouragement throughout the preparation of this work.
model studies, HGG originated in the SVZ grow along
white matter tracts and macroscopically do not show Financial support and sponsorship
involvement of the SVZ. The combination of studies Nil.
[52]
on the adult human SVZ in HGG patients and animal Conflicts of interest
models might shed new light on the functional role of There are no conflicts of interest.
this region in neuro-oncogenesis.
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24 Neuroimmunol Neuroinflammation | Volume 3 | Issue 2 | February 15, 2016