Ginkgo biloba extract (EGb 761) induces apoptosis by the activation of caspase-3 in oral cavity cancer cells.

We have investigated whether Ginkgo biloba extract (EGb 761) induces apoptosis of oral cavity cancer cells and attempted to characterize the apoptotic pathway activated by EGb 761. The inhibition of SCC 1483 oral cavity cancer cells proliferation was noted from 250 micro/ml of EGb 761. Apoptosis was observed after 24 h of incubation with 250 microg/ml EGb 761 and occurred in a time- and dose-dependent manner. Apoptosis was confirmed by DNA fragmentation and PARP cleavage. Co-treatment with the caspase inhibitor (z-VAD-fmk) inhibited apoptosis and PARP cleavage induced by EGb 761. Caspase-3 activity was upregulated by EGb 761 but reduced to the control level by co-treating with z-VAD-fmk. In summary, EGb 761 induces apoptosis of oral cavity cancer cells and caspase-3 is activated in this apoptosis. Therefore, EGb 761 may be considered as a possible chemopreventive agent against oral cavity cancer.