Figure 5

FITC-DPs induced cell death and apoptosis. HtTA (A and C), A2058 (B) cells and normal human fibroblasts (B) were electroporated with 5 μM of the indicated FITC-labeled DPs or with medium only (control). Cells were washed and incubated for 24 and 48 (A) or for 48 (B and C) h. Cell death was detected by measuring LDH release and cell viability was measured with the MTT method (A and B). Representative results of three independent experiments are shown and are expressed as means and standard errors of the means after normalization to the control group. Student t test: **, P < 0.01; ***, P < 0.001. (C) Cells were stained with the Hoechst 33258 dye, and chromatin condensation was evaluated with a fluorescent microscope. Arrows indicate that cells expressing the FITC-conjugated peptide and were positive for chromatin condensation. Scale bar: 5 μm.