Furthermore, a proven and significant up-regulation of Sirt-1 expression in many different tumors, including mouse adenocarcinomas, human colon cancer, breast cancer, squamous cell carcinoma, and prostate cancer cells, suggests Sirt-1 protein as a tumor mediator and therefore as a possible signaling target for the treatment of cancers (42–46). Here, SIRT1 is linked to squamous cell carcinoma.