Radiation Therapy Combined With 5-Aminolevulinic Acid: Effect on Primary Human Meningioma Cells

Radiation therapy (RT) is a standard treatment for certain meningiomas; however, it does not consistently achieve favorable favourable outcomes. Therefore, discovering new agents that can enhance the radiosensitivity of meningiomas is of considerable interest. Evidence suggests that 5-aminolevulinic acid (5-ALA) acts both as a photosensitiszer and a radiosensitiszer. This study aimed to evaluate the efficacy of combining 5-ALA with RT on primary meningioma cells, which were obtained from eight patients during surgery.

Primary meningioma cells were characterized by immunocytochemistry using specific markers. Cell proliferation following treatment with 5-ALA, with or without RT, was evaluated using the WST-1 assay. Accumulation of protoporphyrin IX was evaluated fluorometrically.

Our in vitro investigations indicate that whilste 5-ALA alone reduced cell proliferation, the combination of 5-ALA and RT resulted in more pronounced cell growth inhibition. The cytotoxic doses of 5-ALA markedly varied amongst cells from different meningioma patients. Furthermore, the study revealed that 5-ALA effectively induced the accumulation of protoporphyrin IX, a highly pro-apoptotic and fluorescent photosensitiszer, within the meningioma cells.

Our data suggest that 5-ALA significantly enhances the antitumor antitumour effects of RT, offering a new option for further exploration of 5-ALA combined with RT as a valuable strategy for meningioma treatment.