IL-8 and IL-6 bystander signalling in human glioblastoma cells exposed to gamma radiation.

BACKGROUND

Exposure of cells to ionising radiation causes the release of several factors, such as cytokines, which are likely to be involved in some biological effects occurring in the irradiated cells and in the neighbouring non-irradiated cells (i.e. bystander effect).

MATERIALS AND

METHODS

The release of interleukin (IL)-6 and IL-8 in the culture medium of irradiated human glioblastoma cells was investigated using an ELISA technique. Immunocytochemistry was used to investigate the expression of corresponding cell membrane receptors in irradiated cells and in cells cultured with medium collected from irradiated cells.

RESULTS

The exposure to radiation determined an increase of IL-6 concentration which was dose dependent at 20 hours, whereas IL-8 release was lower than control shortly after irradiation but increased with time, in particular at the dose of 0.5.

CONCLUSION

Our data suggest that these cytokines are differently modulated by radiation and are likely to play a role in the transmission of radiation-induced response, probably orchestrating the inflammatory microenvironment of the tumour.