Figure 4

Preincubation with CPEC (1000 nM for 48 h) additively enhances dFdC-induced (300 nM for 4 h) radiosensitisation in human pancreatic carcinoma Panc-1 cells. Representative example of a proliferation assay (A) or means with standard errors of at least three separate experiments are shown for clonogenic survival after correction for the toxicity of either treatment alone (B, Panc-1: CPEC, 0.53±0.16; dFdC, 0.89±0.13; CPEC+dFdC, 0.10±0.02) or for plating efficiency without the correction (C). Significant radiosensitisation was observed for dFdC alone and for CPEC combined with dFdC (B, P<0.001), but not after CPEC alone.