ZAR1 is methylated in various cell lines, in all germ cell lines (n = 14), in half of the malignant melanoma (n = 4) and kidney cancer cell lines (n = 4), in all mamma (n = 3), and 90% of brain cancer cell lines (glioblastoma; n = 8). This evidence concerns the gene ZAR1 and glioblastoma.