VLDLR and breast carcinoma: To investigate the biological effect of different subtypes of VLDLR on breast cancer cell stemness, we stably overexpressed VLDLR-I/II in MDA-MB-231 cells (Supplementary Figure 2A) and found that the sphere formation capabilities were significantly enhanced by both VLDLR-I and VLDLR-II expression (Figure 2A).