Fig. 14
Murine Model of Ultraviolet Radiation Stress-Induced Senescence. The lung SCC tumor-bearing C57BL/6J mice were treated by UVA irradiation for seven consecutive days (2.2 kJ/m2 for 30s/day). A Histopathology (hematoxylin and eosin-stain) and histochemical detection of SA-β-gal activity of C57BL/6J biopsied tumorous lung. Histopathology: Squamous cell carcinoma was identified in the tumor and shows prominent intercellular bridges (white arrow), keratinization, and a lymphatic invasion pattern (black arrow). Histochemical of SA-β-gal activity: microscopic image of the presence of SA-β-gal activity in C57BL/6J tumorous lung treated by UVA (original magnification, 200×), B Flow Cytometry Gating for Single and Live Cells, Quarter 1: Forward Scatter Area vs. Forward Scatter Height; first gate that was used to exclude any doublets and clumps of multiple cells to eliminate skewed results, Quarter 2: Forward Scatter Area vs. Propidium iodide; gate that is used for live cells and gate out obvious debris (as dead cells often have varied areas and heights that can make data look sloppy), once the single cells of interest were the only cells in our analysis, Quarter 3: Control cells stained with propidium iodide show G1, S, and G2/M phase distributions. Quarter 4: The frequency of G1 senescent cells increased dramatically, and the frequencies of S and G2/M phases decreased significantly. Plots were made using ModFit. C Significantly decreased ZNF334 expression in a senescent murine model treated with UVA. qRT-PCR analysis was performed using RNA prepared from a senescent C57BL/6J biopsied tumor lung treated with 2.2 kJ/m2 of UVA light. GAPDH was used as a reference gene. Data are expressed using the 2−∆∆Ct method. Non-parametric Wilcoxon test was carried out to evaluate statistical differences between groups. Differences were considered significant at p < 0.05. D Significantly decreased TINAGL1 expression in a senescent murine model treated with UVA. qRT-PCR analysis was performed using RNA prepared from a senescent C57BL/6J biopsied tumor lung treated with 2.2 kJ/m2 of UVA light. GAPDH was used as a reference gene. Data are expressed using the 2−∆∆Ct method. Non-parametric Wilcoxon test was carried out to evaluate statistical differences between groups. Differences were considered significant at p < 0.05