ECM1 and neoplasm: To test the role of ABCG1 in ECM1- and integrin αXβ2-induced in vitro 3D growth and in vivo tumor growth, we silenced or overexpressed ABCG1 expression in A8i-A or A8i cells, respectively (Fig. 6g), and found that the number of spheroids in 3D culture, the growth of tumors, and the levels of phosphorylated AKT, FAK, Paxillin, Rac, and Myosin were markedly reduced (Fig. 6h–l).