The effect of taurolidine on brain tumor cells.

BACKGROUND: Although an inhibiting effect of the antibacterial substance taurolidine on several tumor cell lines was suggested in 1990, no specific research has been performed concerning its effect on brain tumor cells.
MATERIALS AND METHODS: Monolayers of rat-derived C6 glioma, mouse-derived HT22 neuronal tumor, and human-derived U373 astrocytoma/glioblastoma cell lines were cultured and incubated with 1 microg/ml to 4 mg/ml of taurolidine. Neuronal and glial brain cells were obtained from rat fetuses at day 15 of gestation and incubated with taurolidine to investigate its effect on normal brain cells.
RESULTS: Following incubation with taurolidine, the tumor cells started to shrink and to become denser. Ultrastructurally, shrinkage of cytoplasm and condensation and marginalization of chromatin could be observed. Exposure to taurolidine at concentrations of 2.8 microg/ml to 2 mg/ml led to cell death of the evaluated tumor cell types. Results of flow cytometry suggested a fragmentation of DNA. Phosphatidylserine expression increased from 6% to 25% following exposure to taurolidine at a concentration of 25 microg/ml. Normal brain cells did not show any significant changes following incubation with taurolidine.
CONCLUSION: The characteristics identified by light and electron microscopy and the data obtained by flow cytometry indicate an apoptotic mechanism of cell death via currently unknown pathways. Taurolidine was found to have a direct and selective antineoplastic effect on glial and neuronal brain tumor cells in vitro.