ANXA5 and glioblastoma: To analyze whether methadone may also enhance the efficacy of the standard anti-glioblastoma therapy [9], U87MG, U251 and primary human glioblastoma cells were treated with a combination of methadone (1–145 μM) and/or temozolomide (100–200 μM) and/or radiation (4 Gy), and cell survival/death was analyzed by crystal violet staining, annexin-V binding, dehydrogenase activity or ATP measurement.