Mepazine (acetate)

Mepazine acetate (Pecazine acetate) is a drug that has the activity to inhibit the protease activity of MALT1. Mepazine acetate is often used to study the role of MALT1 in biology. Treatment of mouse bone marrow precursor cells with mepazine acetate strongly inhibited RANK ligand (RANKL) -induced osteoclast formation. Mepazine acetate also inhibited the expression of multiple osteoclast markers such as TRAP, feline hepsin K, and calcitonin. The protective effect of mepazine acetate was not affected by MALT1 deficiency. The mechanism of action of mepazine acetate may involve MALT1-independent mechanisms, and this aspect needs to be considered in future studies[1].