Influence of Therapeutic Proton Beam on Glioblastoma Multiforme Proliferation Index - A Preliminary Study

The goal of the presented study was to compare the proliferation of different U118 MG and U251 MG glioblastoma cell lines irradiated with proton beam or X-rays in dose range 0.5-10.0 Gy. Cytokinesis-block micronucleus (CBMN) assay was carried out to study changes in proliferation presented as nuclear division index (NDI). Preliminary results suggest that protons and X-rays influence GBM (glioblastoma multiforme) cellular proliferation differently. Therapeutically, a decrease in NDI values with the increase in both types of radiation dose was found only for U251 MG cell line, and thus can be classified as more radiosensitive than U118 MG cell line. Also for U251 MG GBM cell line, a therapeutic proton beam was more effective in inhibition of proliferation than X-rays. Genetic differences between GBMs are supposed to be involved in the increased radiosensitivity, which is planned to be studied further by gene expression analysis.