On the one hand, the ability of resilient states to maintain large epigenetic barriers refractory to non-physiologic cell fate transitions might explain why the NAD+-dependent HDAC/sirtuin pathway is one of the few mechanisms described to mediate the correction or resetting of the abnormal chromatin state of aging cells induced by calorie restriction, the most robust life span-extending and cancer preventing regimen [2, 66–68]. Here, HDAC9 is linked to cancer.