Considering the fact that FAS was more highly expressed by GL261 GICs (both constitutively and after DAC treatment), we hypothesise that CTLs used the FAS/FASL pathway to induce glioma killing only at later time points, in accordance with the finding that FASL can be newly synthesised by CTLs after recognition of antigen presented by target cells [49]. This evidence concerns the gene FASLG and glioma.