Representative histograms after flow cytometric analysis of cell cycle distribution in SISO cells. Cells were treated with a solvent dark control (SDC), mTHPC or 1-OHP alone, or a combination of mTHPC and 1-OHP prior to illumination with 1.8 J/cm2. Fixation and staining with PI were carried out 48 h after illumination. For each sample, 10,000 events were counted and gated for the single cell population (not shown) and cell were assigned to either subG1 (fragmented DNA, apoptotic), G0/G1, S, or G2/M phase. The B3 channel (λEx/Em = 488 nm/655–730 nm) of a MACS Quant flow cytometer. Data were analysed with the MACS Quantify Software.