The role of sirtuins in age-related diseases is an area of rapidly expanding 
investigation. Sirtuins are NAD+ -dependent class III histone deacetylases 
(HDACs) that share extensive homologies with the yeast HDAC Sir2. Class I and 
class II HDACs inhibitors have been identified as potential anticancer agents 
and are in clinical studies, but much less is known about class III HDAC 
inhibitors. However, inhibitors of sirtuins are currently being targeted as 
potential therapeutic agents for disease such as cancer, neurodegenerative 
disease and other disorders as sirtuins are discovered to regulate numerous 
downstream enzymes. Given the link between sirtuins and cancer, understanding 
the functionality of these enzymes may ultimately have significant impact in 
cancer prevention or cancer treatment. This review gives an updated overview 
regarding the regulation of sirtuin enzymes, their implications in cancer, 
various sirtuin inhibitor scaffolds and their insights in drug design.