Efficacy of Anti-Epileptic Drugs in the Treatment of Tumor and Its Associated Epilepsy: An in vitro Perspective

The change in the therapeutic targets from neuron to glia has proved beneficial in the treatment of many psychiatric disorders. The anti-epileptic drugs (AEDs) have been widely prescribed for the treatment of partial and complete seizures, bipolar disorder among others. The current study was carried out to explore the efficacy of some conventional and novel AEDs for the treatment of tumor-associated epilepsy which develops in 29-49% of the patients diagnosed with brain tumors. We used C6 glioma cell line as model system to study the effect of selected AEDs, viz., gabapentin (GBP), valproic acid (VPA) and topiramate (TPM). Morphometry, cell cycle analysis, apoptosis, expression of different protein markers, viz., GFAP, HSP70 and nuclear factor-κB (NFκB) were studied in AED-treated cultures. The study was further extended to rat hypothalamic primary explant cultures, and cell migration and expression of plasticity markers - neural cell adhesion molecule (NCAM) and polysialylation of NCAM (PSA-NCAM) - were studied in the explants. TPM was observed to show more pronounced increase in apoptosis of glioblastoma cells accompanied by significant downregulation in the expression of HSP70 and NFκB. TPM-treated explants also showed highest process ramification and cellular migration accompanied by intense expression of the plasticity markers as compared to those treated with GBP and VPA. Among the 3 AEDs tested, TPM was observed to show more promising effects on cytoprotection and plasticity of C6 glioma cells.