Cultured human glioblastoma U87 cells, which normally do not express L1, were transduced with lentivirus, encoding the recombinant MIF-EGFP gene, for 48 h, then the cells were further transduced with adeno-associated virus mediating the expression of L1-70-Myc and Top1-HA for an additional 24 h. This evidence concerns the gene TOP1 and glioblastoma.