Figure 3. Effects of UV exposure with two different lamp sources: Purple Dawn (PD) and HVC2654025-16W (HVC) on proliferation of HDF, HaCaT, and ARPE-19. (A) The graphs show the cell proliferation measured by Cell Counting Kit-8 at 24, 48, and 72 h after UV exposure. The graphs display the mean values ± SD (n = three). *p < 0.05; **p < 0.01; ***p < 0.001. (B) The histograms show the percentage of Ki67 positive cells identified by ICC assay (n = three ± SD). *p < 0.05; **p < 0.01; ***p < 0.001. (C) The picture shows the percentages of different cell populations (G1, S, and G2/M) as indicated 72 h after UV exposure. Data are expressed with standard deviation. Experiments were conducted in triplicate for each condition (n = three). The * symbol indicates a comparison among the G1 phase under different experimental conditions (*p < 0.05; **p < 0.01), while the # and § symbols correspond to the S phase and G2/M phase, respectively (#p < 0.05; ##p < 0.01; §p < 0.05; §§p < 0.01; §§§p < 0.001).