In Py8119, a murine breast cancer cell line derived from the PyMT-driven tumors, Sh3rf3 upregulation was also observed in the ALDH+ subpopulation versus the ALDH− counterpart (Supplementary Fig. 1b), and Sh3rf3 overexpression increased the capacity of tumorsphere formation by Py8119 (Supplementary Fig. 1c and d). Here, SH3RF3 is linked to breast cancer.