ABSTRACT
PURPOSE: Glioblastoma multiform (GBM) is one of the most common brain tumors. Surgery, radiation therapy, hyperthermia, and chemotherapy are the most common treatments for brain tumors such as GBM. This study investigated the cytogenetic damage caused by hyperthermia, radiation (6 MV-X-rays), and topotecan in glioma spheroids, simultaneously and separately. MATERIALS AND METHODS: Human glioblastoma cell line was cultured to form spheroids 350 µm in diameter that were arranged in eight groups and coded as follows: control, T: topotecan, H: hyperthermia, T + H: topotecan + hypertermia, X 1-10: X-ray with 1-10 fraction irradiation, H + X (1-10): hypertermia + X-ray with 1-10 fraction irradiation, T + X (1-10): topotecan + X-ray with 1-10 fraction irradiation, and H + T + X (1-10): hypertermia + topotecan + X-ray with 1-10 fraction irradiation. DNA damage was then evaluated using clonogenic assay. RESULTS: The effect of combined treatment with X + H + T was greater than the sum of the effects in other groups. In H + T + X group, failure to form colonies was observed in the seventh session. CONCLUSION: Use of X + H + T combination therapy significantly increased cell death and possibly improved the treatment. This suggests that the synergistic effect of different therapeutic methods increased cell death in glioblastoma tumor cells and reduced the necessary dose of radiation in the treatment of tumor in radiation therapy.
