Effects of Cinnamaldehyde on the Viability and Expression of Chemokine Receptor Genes in Temozolomide-treated Glioma Cells

BACKGROUND/AIM: The effects of cinnamaldehyde on glioma are still unclear. We aimed to investigate the effects of cinnamaldehyde on the viability and expression of chemokine receptors CXCR4 and CXCR7 in temozolomide (TMZ)-treated glioma cells. MATERIALS AND METHODS: Cell viability and CXCR4 and CXCR7 expression were measured by western blotting at 72 h after treatment with various concentrations of cinnamaldehyde and TMZ. RESULTS: Cell viability was significantly lower after treatment with 300 muM TMZ, 50 muM cinnamaldehyde, 75 muM cinnamaldehyde, or combined treatment with 300 muM TMZ plus 50 muM or 75 muM cinnamaldehyde than after no treatment (i.e., without TMZ or cinnamaldehyde); and significantly lower after combined treatment with 300 muM TMZ plus 75 muM cinnamaldehyde but not 50 muM cinnamaldehyde, than treatment with 300 muM TMZ alone. Western blotting showed that either single treatments or combined treatments had lower CXCR4 expression (compared to the no-treatment control). Compared to 300 muM TMZ alone, both combined treatment of 300 muM TMZ plus 50 muM cinnamaldehyde or 75 muM cinnamaldehyde had significantly lowered CXCR4 expression. However, CXCR7 expression was not significantly different in all groups. CONCLUSION: Cinnamaldehyde, acting with TMZ, reduces glioma cell viability possibly via decreasing CXCR4 expression.