MELK and cancer: In response to the widespread reports that MELK is a cancer dependency, several companies have developed small molecule inhibitors of MELK that block the activity of the kinase in vitro and that inhibit cancer cell proliferation at micromolar or nanomolar concentrations (Beke et al., 2015; Touré et al., 2016; Johnson et al., 2015a, 2015b; Chung et al., 2012).