Effects of IR and TrxR-inhibition on cell growth. (A) Cell lines U1810 and U1906e were exposed to a single fraction of 2 Gy (grey bars) or 5 Gy (black bars) and then counted and sub-cultured over a 2-week period. Cell counts were normalized against untreated control (white bars). Error bars show standard deviation of three different experiments. (B) Cell line U1810 was exposed to a single fraction of 2 or 5 Gy in combination with a 48-hr treatment with 2.5 μM of the TrxR-inhibitor [Au(SCN)(PEt₃)] (black bars). Cells were then counted and sub-cultured over a 2-week period. The figure shows the end-point number of cells normalized to untreated control (white bars). Error bars show standard deviation of three different experiments. (C) Surviving fractions of irradiated cells at 2 and 5 Gy, respectively (SF₂ and SF₅) as compared to unirradiated controls. (D) Cell line U1810 was exposed to a single fraction of 2 or 5 Gy in combination with a 48-hr treatment with 2.5 μM [Au(SCN)(PEt₃)] followed by continuous culturing with 0.05 μM [Au(SCN)(PEt₃)] (black bars) for a total period of 14 days. The end-point number of cells was normalized to untreated control (white bars). Error bars show standard deviation of three different experiments.