Figure 5.

ZnCl₂ supplementation enhances DNA damage and rescues p53 activity, inhibited by SFN. (a) HCT116 and RKO cells were treated with CDDP (5 µg/mL) alone or in combination with SFN (2 µM) and ZnCl₂ (100 μM). The expression level of the indicated proteins was analyzed by Western blot. Actin was used as protein loading control. Densitometric analyses was performed and reported as histogram in the right panels, plus S.D. * p ≤ 0.01. (b) RT-PCR analysis of total mRNA extracted from HCT116 cells treated as in (a). Densitometric analysis using ImageJ software was applied to calculate the PUMA/28S ratio. (c) HCT116 and RKO cell viability was measured by Trypan blue staining after treatment with cisplatin (CDDP) (5 µg/mL) alone or in combination with SFN (2 µM) and ZnCl₂ (100 μM) for 24 h. The results are expressed as cell death percentage ± S.D. * p ≤ 0.01.