It is primarily active within the nucleus and shares structural similarities with class I and II HDACs.[12] HDAC11 demonstrates both deacetylase and defatty‐acylase activities, with its defatty‐acylase activity being over 10 000 times more efficient than its deacetylase activity.[14a] HDAC11 has been implicated in a variety of diseases, including cancer, inflammatory and immune disorders, cardiovascular diseases, and neurodegenerative conditions.[33, 41] In recent years, there has been a growing interest among researchers in elucidating the metabolic functions of HDAC11. The gene discussed is ACY1; the disease is cancer.