Induction of apoptosis in glioma cells by lycorine via reactive oxygen species generation and regulation of NF-κB pathways.

Glioma is an extremely aggressive primary brain tumor, which is highly resistant to chemotherapy, presenting a therapeutic challenge. Here, we explored the anti-glioma effects and the underlying mechanism of lycorine, an isoquinoline alkaloid isolated from lycoris on glioma cells. We found that lycorine could dose dependently inhibit C6 glioma cell growth and induce cell apoptosis and intracellular reactive oxygen species (ROS) production. The half-maximal inhibitory concentration (IC) values of lycorine on C6 glioma cells at 48 h was 2.85 μM. Meanwhile, lycorine treatment caused dysfunction of the NF-κB signal, as demonstrated by the up-regulation of NF-κB inhibitor protein IκB and the downregulation of the NF-κB phosphorylation protein p-p65. The addition of NF-κB inhibitor SC75741 further confirmed the importance of the NF-κB pathway in lycorine-induced cell-growth inhibition. Moreover, lycorine might act synergically with temozolomide (TMZ) to reduce drug resistance by blocking the NF-κB pathway. Our study suggested that lycorine exerts an anti-glioma effect by inducing ROS production and inhibiting NF-κB, which validated that lycorine may be a potential candidate for glioma treatment alone or in combination with TMZ.