FTO and obesity due to melanocortin 4 receptor deficiency: Besides, other FTO inhibitors such as FB23/FB23-2, MA/MA2, MO-I-500, and, intriguingly, Entacapone have been delineated to harbor a binding ability toward FTO with the aim to reduce the RNA demethylase activity, which should have anti-cancer effects other than anti-obesity effects [54].