U0126, an effective and selective non-competitive inhibitor of MAP kinase, inhibits MEK-1 and MEK-2 with IC50 values of 0.07 and 0.06 μM respectively. U0126 inhibits autophagy and mitophagy.

Rat hepatocarcinoma cells (FAO) stimulated by fetal calf serum (FCS) exhibits a significant proportion in S phase (32.62%) whereas U0126 strongly decreases the proportion of cells in S phase (9.92%) and increases the proportion of cells in G0-G1 phase and to a lesser extent in G2/M[1]. U0126 efficiently reduces progeny virus titers of all tested strains in A549 cells. While nM concentrations of U0126 are efficient to reduce H1N1v and H5N1 (MB1), μM concentrations of U0126 are required to reduce the virus titer of H5N1 (GSB) and H7N7. The EC50 values for U0126-EtOH against H1N1v are 1.2 μM in A549 cells and 74.7 μM in MDCKII cells[2].

In mice, U0126-EtOH (U0126; i.p., 10.5 mg/kg) inhibits tumor growth with a 60-70% reduction 9 days after injection and thereafter[1]. After treatment with U0126-EtOH(U0126; i.p., 30 mg/kg), the vasoconstriction to S6c is markedly reduced in rats[3].