Data di Pubblicazione:
2022
Citazione:
MECHANOPROPERTIES, HETEROGENEITY AND CELL MIGRATION IN GLIOBLASTOMA / M. Crestani ; tutor: N. Gauthier, P. Monzo. Dipartimento di Oncologia ed Emato-Oncologia, 2022 Dec 16. 34. ciclo, Anno Accademico 2022.
Abstract:
Glioblastomas (GBMs) are primary brain tumors endowed with inter- and intra-patient
heterogeneity and extreme di↵usivity. As heterogeneity is studied with genomic and
transcriptomic analysis, little is known on how it is reflected on cell migration, mechanoproperties
and motility modes. Generally, the tumor cells invade the brain moving on
brain vasculature or white matter tracks: Patient-Derived Xenograft (PDX) has been a
standard to reproduce them in order to study GBM invasion. However, PDX presents
many disadvantages, including time consumption, hard standardization, high cost and
ethical concerns.
The present PhD thesis report aims at summarizing the existing literature through
an historical journey that gradually walks the reader towards the state of the art in
the biological knowledge, therapeutic treatments, and bioengineering of GBM. It also
reports the results of this PhD work. They include novel bioengineering tools for
studying the mechanoproperties in GBM and the development of methods to dissect
their migration and motility modes. Finally, a stand-alone assay aims at fostering a
discussion on how the scientific mindset and science have evolved and are evolving to
drive technological innovation in nowadays’ world.
The main goal of this PhD work was to develop bioengineering tools to crack
mechanoproperties and GBM motility. Initially, by utilizing clones of patient-derived
GBM cells that were either highly proliferative or highly invasive, I co-studied their cellular
architecture, migratory, and biophysical properties. One of the milestones of this
PhD work consists in the link between that invasiveness and cellular fitness. The most
invasive cells were sti↵er, developed higher mechanical forces on the substrate, and
moved stochastically. The mechano-chemical-induced expression of the formin FMN1
supports the mechanical cohesion of the cytoskeleton and enhances cell’s mechanoproperties,
leading to a higher motility and invasive phenotype.
In order to scale up the motility screen to several GBM clones, I co-developed SP2G
(SPheroid SPreading on Grids), the live imaging of GBM spheroids spreading on grid
micropatterns mimicking the brain vasculature. To counteract the issues in PDX and
rapidly identify the most invasive sub-populations hidden in heterogeneous GBMs, we
developed an in vivo mimicry platform named SP2G (SPheroid SPreading on Grids).
Live imaging of tumor-derived spheroids spreading on gridded micro patterns imitating
the brain vasculature mimicked 3D motility features observed in brain or 3D matrices.
Using patient-derived samples coupled with a semi-automated ImageJ/Fiji macro suite,
SP2G easily characterized and sorted di↵erences in cell migration and motility modes
through a set of 6 parameters (area expansion, di↵usivity, boundary speed, collective
migration, directional persistence, hurdling). Moreover, SP2G exposed the hidden
intra-patient heterogeneity in cell motility that correlated molecularly to specific integrins.
Thus, SP2G is intended as a versatile and potentially pan-cancer workflow to
identify the invasive tumor sub-populations in patient-derived specimens. SP2G represents
an integrative tool, available as open-source Fiji macro suite, for therapeutic
evaluations at single patient level.
Tipologia IRIS:
Tesi di dottorato
Keywords:
GLIOBLASTOMA ; MIGRATION ; HETEROGENEITY ; MICROSCOPY
Elenco autori:
M. Crestani
Link alla scheda completa: