Figure 7.

iNOS Overexpression Negates the Anti-tumor Effect of Sirt1-Overexpressing MSCs In Vivo

(A) Schematic representation depicting the experimental design to investigate the efficacy of the iNOS-overexpressing AdSirt1-MSC transfusion during liver metastasis of colorectal carcinoma in mice. (B) Liver surface metastatic nodules were detected macroscopically. Representative photographs show the hepatic tumor metastases in mice from the above four groups (21 days post-treatment). (C) H&E staining was used to evaluate liver samples of mice (21 days post-treatment) from the above four groups. Scale bars, 100 μm. (D) Representative immunohistochemical staining of CD8 in liver samples in mice (21 days post-treatment) from the above four groups are shown. Scale bars, 100 μm. The black arrows point to CD8⁺ T cells. (E) Quantitation of CD8⁺ T cells at hepatic tumor site in mice (21 days post-treatment) from the above four groups. At least five fields (magnification, ×200) were counted for each specimen. **p < 0.01 versus CT26 group. p > 0.05 versus CT26 group; NS, not significant (p > 0.05).