Figure 1

A proposed model for ABCG2 regulation by miR-519c. ABCG2 mRNA adopts predominantly a long form of 3′UTR in parental S1 cells but only the shorter forms in drug-resistant S1M1-80 cancer cell line [16, 17]. MiR-519c (and miR-328) can only bind to the long ABCG2 3′UTR in parental cells, thus allowing ABCG2 in resistant cells to escape from their repression and thereby acquiring a higher expression.