Figure 2.

Radiosensitivity after guanine nucleotide-binding protein 1 (GBP1) knockdown and overexpression, as determined by modified high-density survival assay. (a,b) GBP1 knockdown increased radiosensitivity both in clinically relevant radioresistant (CRR) and parental cells. GBP1 knockdown was carried out with Hs_GBP1_8. (c) Parental cells transfected with GBP1 (Parental GBP1) did not show significant changes in radioresistance compared to parental cells with an empty vector (Parental cont). Exponentially growing cells were seeded in 25-cm² flasks and incubated for 24 h; cells were then irradiated and incubated for another 72 h. Subsequently, 10% of the cells in each flask were seeded into another flask and incubated for a further 72 h and live cells were counted. scr, scramble siRNA.