AFM investigation of mechanical properties of glioblastoma multiforme cells and their relation to motility

Glial tumors are clinically classified in 4 groups according to their malignancy level. Glial tumors belonging to the IV group are called Glioblastoma Multiforme (GBM) and they are among the most aggressive brain tumors. In the recent years the mechanical phenotype of cells has been recognized as a valuable marker of their malignancy level [1-3]. Here we studied by AFM the mechanical behavior of U87mg cells when exposed to a drug which interferes with their cytoskeleton affecting also their migration ability. We found that U87mg cells exposed to the tested drug presented a decreased migration potential which is correlated with an increased stiffness of the cells and with a loss of polarity. By exploiting AFM Dynamic Mechanical Analysis we also characterized the behavior of the cells for different probing frequencies. By exploiting immunofluorescence microscopy we also investigated the effect of the tested drug on the reorganization of the cell cytoskeleton finding a strong increase of the presence of stress fibers.