Correlation of Telomere Length and Radiosensitivity in Human Laryngeal Squamous Carcinoma Cells

Objective 　To investigate the correlation of telomere length and radiosensitivity in human laryngeal squamous carcinoma cells and to seek for the molecular marker that can be used to predict cellular intrinsic radiosensitivity. Methods 　The long-termly cultured human laryng-eal squamous carcinoma cell line (Hep-2) was irradiated by the dose of 0, 2, 4, 8, 12 Gy for three times and their survival progenies were obtained through subculturing 20 generations. Radiosensitivity index SF₂ was measured by clonogenic assay and telomere length (mean length of telomere rest riction f ragment s, TRF) was examined by South-ern2-blotting. Results 　With the radiation doses' increasing, the SF₂ of survival progenies enhanced ( P <0. 05) and the TRF prolonged ( P < 0. 01) . Furthermore, the SF₂ correlated positively with the TRF( r =0. 921, P < 0. 01) . Conclusion 　The survival progenies of Hep-2 cell line with different radiosensitivity can be obtained by irradiating with different doses. Furthermore, radiosensitivity correlates inversely with telomere length, which suggests that telomere length may be used as the predictor for cellular intrinsic radiosensitivity.