YW3-56 is a potent peptidylarginine deiminase (PAD) inhibitor, with an IC50 of 1-5 μM for PAD4.

Compared with Cl-amidine, YW3-56 shows >60-fold increase in cell growth inhibition efficacy (IC50 about 2.5 μM) but only 5-fold increase in PAD4 inhibition (IC sub>50 about 1-5 μM). At 2-4 μM concentrations, YW3-56 displays mainly cytostatic effects by slowing cell division, whereas at higher concentrations, it exerts cytotoxic effects by altering cell morphology and killing cells[1].

[1]. Wang Y, et al. Anticancer peptidylarginine deiminase (PAD) inhibitors regulate the autophagy flux and t he mammalian target of rapamycin complex 1 activity. J Biol Chem. 2012 Jul 27;287(31):25941-53.