Providing that numerous protein kinase inhibitors [22,36,37,38,39,40], including PIM inhibitor [41], were reported to interact with ABCB1 and ABCG2, we investigated the effect of TP-3654 on ABCB1- and ABCG2-mediated drug transport and multidrug resistance in a panel of drug-sensitive cancer cell lines and their respective ABCB1- and ABCG2-overexpressing multidrug-resistant cancer cell lines. The gene discussed is WEE1; the disease is cancer.