BCL2 and central nervous system cancer: Some authors advocated that the SDT mediated by hematoporphyrin monomethyl ether (HMME) can induce apoptosis on C6 glioma cells in vitro and suggest that the mitochondrial signal pathway may play a pivotal role, because of the observed production of ROS, loss of MMP and Bcl-2 and protein expression in caspace-9, caspase-3 and Bax [25, 29].