Although we cannot exclude other mechanisms that may also contribute to the resensitization of multidrug-resistant cancer cells or the potential adverse drug reactions that may occur in combination therapy [18,79,80], our results demonstrated that sitravatinib is capable of reversing multidrug resistance mediated by ABCB1 and ABCG2 at submicromolar concentrations and the concomitant administration of sitravatinib in chemotherapy warrants further investigation. The gene discussed is ABCG2; the disease is cancer.