Figure 3From: The relation between deoxycytidine kinase activity and the radiosensitising effect of gemcitabine in eight different human tumour cell lines Relationship between gemcitabine concentration and the combination index. Relationship between the concentration of gemcitabine (dFdC) and the mean combination index (CI) for ECV304, FaDu, H292, A549, CAL-27, MCF-7 and HT-29 cells. The cells were treated during 24 h with gemcitabine immediately before radiotherapy (0–8 Gy). A CI value between 0.9 and 1.1 indicates only additivity. Moderate synergism is depicted by CI values between 0.7 and 0.9, synergism by CI values below 0.7.Back to article page