PPARGC1A and cancer: Future studies will determine whether nuclear Perilipin 5 regulates deacetylation states of known SIRT1 targets beyond PGC-1α, such as p53, FOXO, NFκB, LXR, CRTC2 and SREBP-1 (ref. 49) This last question is significant given the known and proposed roles of SIRT1 as an integrator of metabolic signalling relevant to cancer biology, aging, inflammation, thermogenesis and exercise, in addition to energy balance.