Research Paper Volume 12, Issue 8 pp 6823—6851

Figure 7. IGFBP2 suppression leads to enhanced apoptosis of senescent psoriatic keratinocytes. (A) Pso KC and healthy KC cultures at passage P4 were silenced or not for IGFBP2 or p21 for 48 hours, and treated or not with M4 for 24 hours. Apoptosis was examined by measuring Annexin V/PI fluorescent staining through FACS analysis. Graphs show the mean ± SD of the percentage of AnnV/PI double-positive cells of three independent experiments. *p ≤ 0.05, as calculated by paired Student’s t test comparing si-IGFBP2 or si-p21 with si-NC, or untreated with M4. (B) Protein lysates of untreated healthy KC and pso KC, silenced or not for IGFBP2 or p21, were analysed by WB to confirm IGFBP2 or p21 silencing. Graphs show the mean ± SD of densitometric intensity (D.I.) of three independent experiments. *p ≤ 0.05, **p ≤ 0.01 as calculated by paired Student’s t test comparing si-IGFBP2 or si-p21 with si-NC. (C) Protein extracts of pso KC at passage 4, silenced or not for IGFBP2, or p21 for 48 hours, and stimulated or not with M4 for 24 hours, were subjected to WB for the detection of IGFBP2, p21, p-p21, procaspase 3, p-JNK and JNK protein expression. WB panels are representative of three independent experiments and graphs show the mean ± SD of densitometric intensity (D.I.) of three independent experiments. *p ≤ 0.05, **p ≤ 0.01 as calculated by paired Student’s t test comparing si-IGFBP2 or si-p21 with si-NC.