Cobimetinib is a selective inhibitor of mitogen-activated protein kinase kinase (MEK) (IC50: 0.9 nM). Cobimetinib specifically binds to and inhibits the catalytic activity of MEK1, resulting in inhibition of extracellular signal-related kinase 2 (ERK2) phosphorylation and activation and decreased tumor cell proliferation.
Cells are plated in quadruplicate at a density of 3,000 per well in 384-well plates in normal growth medium and allowed to adhere overnight. Compounds are added in 10 concentrations based on a 3-fold dilution series. Cell viability is measured 72 h later using the CellTiter-Glo Luminescent Cell Viability Assay.(Only for Reference)