Figure 7. Short term AZD8055 exposure does not immortalise or transform primary human skin fibroblasts. (A) HF043 fibroblasts at CDP55 were treated with 35nM AZD8055 either continuously (green triangles) or for 5 population doublings followed by release from drug (black arrow indicates time of drug removal; growth curve shown by orange circles) compared with cells incubated with DMSO as control (blue diamonds). The end point of the growth curve denotes when cells ceased proliferation and became fully senescent (NB cells under continuous AZD80055 treatment continued for several PDs beyond the graph shown but also eventually died). (B) Phase contrast photomicrographs of cells in culture either following release from AZD8055 (‘Recovery’) or under continuous drug treatment (‘Continuous’). The left panel shows cells 8 days after drug release and the right panel shows cells at very late CPD: CPDs are shown in white boxes within the micrographs.