134
to target GSC specific biomarkers and angiogenic blood vessels might therefore
prove to be ineffective in future. The recent development of transgenic models
which can recapitulate, to a certain extent, the heterogenous nature of GBMs could
allow for the better identification of microenvironmental components which have a
relevant impact on GSC proliferation and survival. Knowledge about the interac-
tions between GSCs and their microenvironment, cellular plasticity within GBMs
and the cellular signaling cascades that maintain stemness of GSCs would allow for
the targeting of multiple critical events within tumors. Delivering GSC targeted
lethal therapeutics using genetically engineered cellular components of GSC micro-
environment could potentially reduce disease recurrence (Birbrair et al. 2016 ).
Investigations of the biology of GSCs and how they become resistant to therapy
can also extend to greater understanding of the role of the microenvironment in their
maintenance and survival. It is therefore essential to appreciate the highly integrated
nature of the GSC niche consisting of various cell populations with regards to their
cellular functions and identity.
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