SIRT6 and cancer: For instance, DNA repair promotion may helpevasion from tumorigenic transformation at early phases of cancer.On the other hand, the same mechanism may facilitate cancer progressionat later stages or decrease the effectiveness of cytotoxic drug chemotherapy.It is worth noticing that the upregulation of SIRT6 in certain typesof cancers76−79 may be representative of a compensatory effect rather than the causeitself of tumor initiation and/or progression.76