Figure 5. PPG-substituted TFOs induce DSBs. (A) Immunofluorescence of triplex-induced γH2AX foci 24h post-treatment with AG30 and A8G30. (B) Western blot analysis of γH2AX protein levels 24h after TFO treatment. (C) Detection of caspase-mediated cleavage of PARP as a measure of triplex-induced apoptosis. Treatment with the PPG-substituted TFO, A8G30 resulted in similar p53 phosphorylation levels at serine 15, as AG30.