Ad-p53(Multivir)

Hypertrophic scarring is a serious fibrotic skin disease, and the abnormal activation of hypertrophic scar fibroblasts (HSFs) intensifies its pathogenesis. Our previous studies have demonstrated that the dysregulation of autophagy in HSFs is associated with fibrosis. However, knowledge regarding the regulation of HS fibrosis by p53-modulated autophagy is limited. Here, we investigated the effect of p53-modulated autophagy on HS fibrosis. The overexpression of wtp53 (Adp53) promoted autophagic capacity and inhibited collagen and α-SMA expression in HSFs. In contrast, LC3 (AdLC3) overexpression did not suppress Col 1, Col 3, or α-SMA expression, but LC3 (shLC3) knockdown downregulated collagen expression. Adp53-modulated autophagy altered Bcl-2 and Bcl-xL expression, but AdLC3 affected only Bcl-xL expression. Silencing Bcl-xL suppressed collagen expression, but autophagy was also inhibited. Flow cytometry showed that the silencing of Bcl-2 (sibcl-2), Bcl-xL (sibcl-xL), and Adp53 significantly increased apoptosis in the HSFs. Therefore, wtp53 inhibited fibrosis in the HSFs by modulating autophagic HSF apoptosis; moreover, the inhibition of autophagy by sibcl-xL had antifibrotic effects. In addition, treatment with Adp53, AdLC3, shLC3, sibcl-2, and sibcl-xL reduced scar formation in a rabbit ear scar model. These data confirm that wtp53-modulated autophagy and autophagic HSF apoptosis can serve as potential molecular targets for HS therapy.

Cross-reacting material 197 (CRM197) is a mutant form of the diphtheria toxin. Recent studies have found that CRM197 exerts an experimental antitumor effect on several types of tumors. This study applied a novel treatment of adenovirus-mediated CRM197 (AdCRM197) to human ovarian cancer cells. Interestingly, it was found that A2780 cells were sensitive to AdCRM197, but SKOV3 cells were resistant to it. Since SKOV3 cells are p53 deletion cells, while A2780 cells are p53 wild-type cells, it was postulated that p53 might play a key role in AdCRM197-induced apoptosis. This presumption was demonstrated by means of knockdown of p53 of the A2780 cells through lentivirus-mediated RNA interference. This knockdown resulted in the A2780 cells becoming resistant to AdCRM197. To verify this presumption further, the wild-type p53 gene in the SKOV3 cells was replaced with adenovirus-mediated p53 (Adp53). As expected, AdCRM197 plus Adp53 resulted in apoptosis of the SKOV3 cells. The combined treatment of AdCRM197 plus Adp53 also showed a good antitumor effect in the in vivo experiment on nude mice with xenograft tumors. Taking these results together, it is concluded that AdCRM197 induces apoptosis of human ovarian cancer cells via the p53 pathway. Moreover, it was found that Adp53 can reverse the resistance of p53-deletion human ovarian cancer cells to AdCRM197. The combination of AdCRM197 and Adp53 may be a potentially effective method for overcoming the resistance of p53-deficient human ovarian cancer to AdCRM197.