Studies have shown that ABCG2 can transport a variety of anti-tumor drugs, such as epirubicin, daunorubicin, irinotecan, doxorubicin, topotecan, 9-aminocamptothecin and mitoxantrone (Doyle and Ross 2003; Zeng et al. 2020). Here, ABCG2 is linked to neoplasm.