Our findings demonstrated that at sub-micromolar concentrations, furmonertinib sensitized multidrug-resistant cancer cells overexpressing ABCB1 or ABCG2, as well as cells with ectopic expression of human ABCB1 or ABCG2, to cytotoxic drugs in a concentration-dependent manner (Figure 1 and Figure 2). This evidence concerns the gene ABCB1 and cancer.