Study of Molecular Mechanism of the Interaction Between MEK1/2 and Trametinib with Docking and Molecular Dynamic Simulation.

Trametinib was endorsed by the FDA in 2013 as a single agent for adult melanoma patients. Trametinib inhibits cell growth and proliferation in multiple tumor xenografts by preventing RAF phosphorylation of MEK and thus restricting accumulation of activated MEK. In this study, the focus of investigation was the mechanism of the interaction between trametinib and MEK1/2 via computational simulation. To specify the best interaction site of inhibitor with MEK1/2 based on the interaction energy ranking, first we performed a docking and then we studied the interactions of the ATP-bound MEK with trametinib, with RAF and the complex of the ATP-bound MEK-trametinib with RAF via molecular dynamic simulations. The results showed that trametinib inactivates the enzyme by bonding to a group of amino acids including Lys97/101, SER218/216, Asp208/212, and Met143/147 in MEK1/2. By bonding to the essential amino acids, trametinib inhibits the activity of the enzyme. All in all, the acquired results can be of great use in designing new inhibitors.