Glioma Cell Migration on Three-dimensional Nanofiber Scaffolds Is Regulated by Substrate Topography and Abolished by Inhibition of STAT3 Signaling

Abstract

A hallmark of malignant gliomas is their ability to disperse through neural tissue, leading to long-term failure of all known therapies. Identifying new antimigratory targets could reduce glioma recurrence and improve therapeutic efficacy, but screens based on conventional migration assays are hampered by the limited ability of these assays to reproduce native cell motility. Here, we have analyzed the motility, gene expression, and sensitivity to migration inhibitors of glioma cells cultured on scaffolds formed by submicron-sized fibers (nanofibers) mimicking the neural topography. Glioma cells cultured on aligned nanofiber scaffolds reproduced the elongated morphology of cells migrating in white matter tissue and were highly sensitive to myosin II inhibition but only moderately affected by stress fiber disruption. In contrast, the same cells displayed a flat morphology and opposite sensitivity to myosin II and actin inhibition when cultured on conventional tissue culture polystyrene. Gene expression analysis indicated a correlation between migration on aligned nanofibers and increased STAT3 signaling, a known driver of glioma progression. Accordingly, cell migration out of glioblastoma-derived neurospheres and tumor explants was reduced by STAT3 inhibitors at subtoxic concentrations. Remarkably, these inhibitors were ineffective when tested at the same concentrations in a conventional two-dimensional migration assay. We conclude that migration of glioma cells is regulated by topographical cues that affect cell adhesion and gene expression. Cell migration analysis using nanofiber scaffolds could be used to reproduce native mechanisms of migration and to identify antimigratory strategies not disclosed by other in vitro models.

The characteristics of Ishikawa endometrial cancer cells are modified by substrate topography with cell-like features and the polymer surface

“…15,34 Because expression of signaling molecules is modified by the physical nature of a cell's environment, it is important that we reach a greater understanding of the effects of these interactions on the development of cancers. [35][36][37] In addition, we also noted, by using a similar topography with a different polymer, pST, that the topographical environment combines with polymer characteristics to have an important role in influencing the cell behavior through the physical characteristics. Further, cells cultured on imprinted pST had smaller area and slower rate of proliferation compared to cells on (f)pST -the converse to the relationship of cells on pMA.…”

In Vitro Modeling of Tissue-Specific 3D Microenvironments and Possibile Application to Pediatric Cancer Research

“…One of the first experiments on brain tumor cells 3D growing in a bioreactor was presented by Ingram and collaborators [260]. Several malignant glioma cell lines were introduced in the NASA rotary cell culture system, forming spheroids with an increasing expression of the adhesion molecule CD44 over the time in culture [260].…”

“…Several malignant glioma cell lines were introduced in the NASA rotary cell culture system, forming spheroids with an increasing expression of the adhesion molecule CD44 over the time in culture [260]. An exhaustive study on brain tumor aggregates generated using the 3D RCCS TM has been presented recently by Smith and collaborators [261].…”

Biomimetic Strategies for the Glioblastoma Microenvironment

“…Techniques to fabricate nanofibers, such as electrospinning, have been used to mimic the delicate fibrous structures of the white matter tracts (Johnson et al, 2009;Agudelo-Garcia et al, 2011;Rao et al, 2013b;Sharma et al, 2013;Beliveau et al, 2016;Cha et al, 2016). The behavior of glioma cells on nanofibers was observed to be a function of substrate topography, as GBM cells migrated much faster on aligned fibers than on random fibers (Johnson et al, 2009;Beliveau et al, 2016).…”

“…The behavior of glioma cells on nanofibers was observed to be a function of substrate topography, as GBM cells migrated much faster on aligned fibers than on random fibers (Johnson et al, 2009;Beliveau et al, 2016). This in vivo-like behaviors of glioma cells is associated with STAT3 signaling, a driver of malignancy during GBM progression (Agudelo-Garcia et al, 2011). Modification of both biochemical and biophysical features of nanofibers has a significant effect on GBM migration (Rao et al, 2013b;Sharma et al, 2013), emphasizing the importance of biomimetic approaches to understanding the behaviors of glioma.…”