CD44 and breast cancer: To explore whether Fzd7 was related to BC cell stemness, we interrogated CCLE database, and found a correlation of FZD7 with a panel of stemness-related genes including CD44, LGR5, NOTCH2, EGFR, IL6 as well as TNC [18] and ANTXR1 [19] (Fig. 2a, Supplementary file 1: Fig. S4A).