Transcriptional Characterization of Glioma Neural Stem Cells Diva ...

Chapter 9
Discussion
9.1 Digital Profiling of GNS Cell Lines
Gliobastoma multiforme is the most common primary brain tumour and the
most aggressive glioma in adults. No effective solution has been embodied
as a treatment yet, causing the prognosis for this disease to be very poor,
with a median survival time of 15 months [472]. The extensive cellular het-
erogeneity typical of glioblastomas is confirmed by the consistently different
molecular signatures and copy number variations observed in the subclasses
present within the primary and secondary subtypes [154,334,450]. These ob-
servations are very important since they point at the need for approaching
treatment research from a more molecular standpoint that allows for patient
treatment diversification, in which the patient’s genome is specifically tailored
to obtain the most effective results. An important finding within the cancer
stem cell field in the context of glioblastomas, was the observation that these
tumours contain a population of cells with similarities to NS cells. Before
then, gliomas were studied as cancer cell lines, which hid the underlying stem
cell component of the tumour by causing it to differentiate and could therefore
never be specifically targeted. NS cells give rise to both neurons and glia during
the development of the nervous system and are present in restricted regions of
the adult human brain, where they constitute proliferating germinative zones
that are active throughout adulthood [248]. According to the cancer stem cell
hypothesis, such stem cell-like cell populations are responsible for maintaining
cancers, as well as giving rise to the differentiated progeny responsible for the
cellular diversity of many neoplasias, including glioblastoma [379]. If this is
the case, isolating and characterizing the glioma cancer stem cells will be key
to developing efficient therapies for glioblastoma multiforme.
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