SIRT1 and neoplasm: Together, these findings suggest that abrogation of epigenetic repression that accompanies polyp progression could be one of the mechanisms for the reduced tumor burden that we observed in APC+/min SIRT1−/− animals, raising the exciting possibility that SIRT1 inhibitors, similarly to inhibitors of DNA methyltransferase and class I/II HDACs, could be used for epigenetic therapy of cancer.