Figure 2.
Cancer stem cells characterized with relaxed chromatin structure exhibited increased formation of UV-induced 6-4PP, but not CPD. CSCs were isolated from ovarian cancer cell lines 2008C13 (A–C) and SKOV3 (D–F). Immunoblotting was conducted to determine histone modifications in these CSCs and their corresponding bulk cancer cells (A, D). Cells were UV irradiated at 10 J/m2, genomic DNA was isolated and subjected to ISB to detect the formation of UV-induced 6-4PP and CPD. ssDNA was detected as a loading control (B, E). The intensity of each band was quantitated, and relative amounts of varying DNA lesions were calculated by normalizing to ssDNA first, and then to their corresponding bulk cancer cells (C, F). N = 3; Bar: SD. **P < 0.01 compared with bulk cancer cells.