International Journal of Molecular and Cellular Medicine (IJMCM)

Glioblastoma multiform (GBM) is a lethal brain tumor with limited treatment options. This study investigated the combined effect of two natural compounds, formononetin (FMN) and magnolol (MAG), on T98G glioblastoma cells, focusing on oxidative stress mechanisms. 
Cell viability was assessed via MTT assay to determine IC₅₀ values and synergy (Chou-Talalay method). Proliferation, migration (wound healing), colony formation, and apoptosis (Hoechst staining) were evaluated. Gene expression (qPCR) of targets like survivin, cyclin D1, and antioxidant enzymes (SOD, CAT, GPX) was analyzed. Enzymatic activities and total antioxidant capacity (TAC) were measured. 
FMN and MAG synergistically reduced cell survival (CI=0.72 at 80 µM each). Combination treatment significantly inhibited proliferation, migration, and colony formation more effectively than single agents. This impounds downregulated pro-survival genes (survivin, cyclin D1, MMP-9) and upregulated pro-apoptotic Bad. Paradoxically, it also enhanced antioxidant enzyme activity and TAC. Despite this compensatory response, the treatment induced significant nuclear fragmentation indicative of apoptosis. 
The FMN and MAG combination exerts potent synergistic antiglioblastoma effects by disrupting proliferation and survival pathways, ultimately inducing apoptosis, even while triggering a compensatory antioxidant response. These in vitro findings provide a hypothesis-generating foundation for further investigation of formononetin and magnolol as a potential combinatorial approach for glioblastoma, pending rigorous in vivo validation and blood-brain barrier permeability studies.