Src kinase assay

Cells were grown to 70 – 80% confluency and treated with different concentrations of AZD0530 depending on the cell line (U251 – 3 μmol/L and NSC11 – 10 μmol/L) for 6 h (U251) or 2 h (NSC11) prior to 2 or 6 Gy irradiation. After irradiation the cells were collected at 2 h (NSC11) and 6 h (U251). Src kinase activity was quantified using a Universal Tyrosine Kinase Assay kit (Takara Bio Inc.) according to the manufacturer’s instructions. Src protein from the lysates of tumor cell lines was collected by immunoprecipitation using an anti-Src (IgG Rabbit; Cell Signaling (#2109)) antibody and Protein G Sepharose™ 4 Fast Flow beads (GE Healthcare. Src kinase activity was assessed by measuring absorbance at 450 nm using a Synergy H1 microplate reader (BioTek).