RESUMO
INTRODUCTION: Overall survival of high-risk neuroblastoma patients is still poor, emphasizing the need for novel therapeutic options. There is evidence for anti-cancer properties of the herbal substances thymoquinone and curcumin. These substances are isolated from Nigella sativa L. and Curcuma longa L., respectively, which are used in traditional medicine. OBJECTIVE: We investigated cytotoxic effects of thymoquinone and curcumin on neuroblastoma cell lines NLF, NB69, and SK-N-BE(2), in vitro. METHODS: Cytotoxicity of compounds was investigated by MTT cell viability assays. For analyzing effects on cell proliferation BrdU assays were employed and induction of apoptosis was detected by Cell Death ELISA assays. RESULTS: Both substances showed cytotoxic effects in all three neuroblastoma cell lines, whereby primary human fibroblast cells reacted less sensitively. Overall, lower IC50 values could be calculated for curcumin (3.75-7.42 µM) than for thymoquinone (5.16-16.3 µM). Decreased proliferation and increased apoptosis rates were observed under treatment. CONCLUSIONS: Both substances showed anti-tumoral properties on neuroblastoma cell lines and should be further investigated as therapeutic agents.