Figure 3.

Exercise induces the up-regulation of p53 and apoptosis in tumor tissues. (A) Western blots for various proteins involved in apoptosis are shown. Tumors from exercising mice had increased levels of p53 and Bax relative to sedentary mice. MDM2 indicates mouse double minute 2 homolog/E3 ubiquitin-protein ligase Mdm2; Puma, B-cell leukemia/lymphoma 2 (Bcl2) binding component; BCL-XL, B-cell lymphoma-extra large; Bax and Bak, proapoptotic Bcl2 family members. (B) In immunohistochemical analysis for active caspase 3, significantly higher levels of this apoptotic intermediary were observed in lung tumors from exercising mice compared with lung tumors from sedentary (control [Ctrl]) mice.