MELK and cancer: Several studies reported that high expression of MELK is required for cancer cell growth, invasiveness, cell cycle progression, stemness, radiation-, and chemo-resistance in cancer.14,17–24,50–55 Similar to gene knockdown studies, MELK inhibitors also reported to be very effective in both in vitro and in vivo studies despite the fact that these inhibitors have significant off-target effects.7,56–64 Recently, Touré et al.65 discovered a novel MELK inhibitor using a virtual screening high throughput approach.