Anti-inflammatory Effects of Atorvastatin by Suppressing TRAF3IP2 and IL-17RA in Human Glioblastoma Spheroids Cultured in a Three-dimensional Model: Possible Relevance to Glioblastoma Treatment

Glioblastoma multiform (GBM) is a primary malignant brain tumor with a few therapeutic targets available for it. The interaction between the immune system and glioma is an important factor that could lead to novel therapeutic approaches to fight glioma. In this study, we investigated in vitro anti-inflammatory and apoptotic activity of atorvastatin in different concentrations 1, 5, and 10 μM on glioma spheroid cells cultured in a three-dimensional model in fibrin gel that indicate the complex in vivo microenvironment better than a simple two-dimensional cell culture. A mechanistic insight into the role of IL-17RA, TRAF3IP2, and apoptotic genes in progression of glioma could provide an important way for therapy of malignant tumors with manipulation of this inflammatory axis. To reach for these aims, after 24 and 48 h exposure with different concentrations of atorvastatin, caspase-8, caspase-3, Bcl-2, TRAF3IP2, and IL-17RA gene expression were assayed. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and cell cycle assay were used for evaluating the cell apoptosis and proliferation. The results showed that atorvastatin has anti-inflammatory and apoptotic effects against glioma spheroids. Atorvastatin induced the expression of caspase-3 and caspase-8 and downregulated the expression of Bcl-2, TRAF3IP2, and IL-17RA especially at 10 μM concentration. These effects are dose dependent. The most likely mechanisms are the inhibition of inflammation by IL-17RA interaction with TRAF3IP2 and NF-κB signaling pathway. Finally, these results suggest that atorvastatin could be used as an anti-cancer agent for glioblastoma treatment.