gms | German Medical Science

Objective: The transformation of glioblastoma cells into tumor stem cells could be stimulated by treatment with glucocorticoids, promoting further proliferation. Due to the poor prognosis and short survival rates of glioblastoma, the search for alternative treatment methods becomes inevitable. In this project, we examined the possibility of treatment with riluzole to reverse the dexamethasone effect on the progression of various stem cell markers.

Methods: The U87MG glioblastoma cells were treated with riluzole (25µM) for 72 h and after that dexamethasone (1 µM) was added as one-time treatment and the cells were incubated for further 72 h. The expression of the following genes, in relation to the housekeeper ß-Actin, was examined by quantitative PCR: CD44, MMP2, N-Cadherin, Notch1, CD90, TFPi2.

Results: The pretreatment of U87MG cells with riluzole suppressed the expression of stem cell markers and markers associated with aggressive and invasive behavior. The expression of CD90 was significantly reduced in comparison to the dexamethasone treated cells alone (***p<0.0005). Furthermore, significant increase in expression of the TFPi2 gene (*p <0.05) was detected. Riluzole’s pretreatment did not show an effect on the expression of other analyzed stem cell genes.

Conclusion: As expected, the expression of certain stem cell markers was significantly upregulated by dexamethasone treatment. Pretreatment with riluzole showed promising results, reducing the effects of dexamethasone on progression of certain stem cell marker. Nonetheless, the effect of this treatment should be confirmed by further studies examining additional genes (proteins) as well as in functional assays, e.g. neurosphere formation, resistance to chemotherapy, migration etc.