Clonogenic assay in combination with cilengitide in breast cell lines . Clonogenic assays were performed with our panel of breast cell lines. Cells were plated at specific cell numbers and treated with indicated doses of cilengitide. After 1 hr of treatment, cells were irradiated and then incubated for up to 4 weeks to allow colony formation. Cells were then stained and counted. All four cell lines show small dose enhancement ratios with the addition of cilengitide, indicating no or very little radiosensitization effects. A) T-47D (DER – 1.21), B) MCF-7 (DER – 1.25), C) MDA-MB-231 (DER – 1.27), D) MDA-MB-231 (DER – 1.15). Figures represent the average of three experiments.