On-Chip Clonal Analysis of Glioma-Stem-Cell Motility and Therapy Resistance

Enhanced
glioma-stem-cell (GSC) motility and therapy resistance are considered
to play key roles in tumor cell dissemination and recurrence. As such,
a better understanding of the mechanisms by which these cells disseminate
and withstand therapy could lead to more efficacious treatments. Here,
we introduce a novel micro-/nanotechnology-enabled chip platform for
performing live-cell interrogation of patient-derived GSCs with single-clone
resolution. On-chip analysis revealed marked intertumoral differences
(>10-fold) in single-clone motility profiles between two populations
of GSCs, which correlated well with results from tumor-xenograft experiments
and gene-expression analyses. Further chip-based examination of the
more-aggressive GSC population revealed pronounced interclonal variations
in motility capabilities (up to ∼4-fold) as well as gene-expression
profiles at the single-cell level. Chip-supported therapy resistance
studies with a chemotherapeutic agent (i.e., temozolomide) and an
oligo RNA (anti-miR363) revealed a subpopulation of CD44-high GSCs
with strong antiapoptotic behavior as well as enhanced motility capabilities.
The living-cell-interrogation chip platform described herein enables
thorough and large-scale live monitoring of heterogeneous cancer-cell
populations with single-cell resolution, which is not achievable by
any other existing technology and thus has the potential to provide
new insights into the cellular and molecular mechanisms modulating
glioma-stem-cell dissemination and therapy resistance.