Subsequently, we verified these findings by assessing the MTX-211 cytotoxicity in HEK293 cells and HEK293 cells transfected with human ABCG2 (R482-HEK293), demonstrating that ABCG2 confers resistance to MTX-211 in cancer cells (Figure 1A,B) and the ABCG2-transfected cells (Figure 1C). Here, ABCG2 is linked to cancer.