FGF1 and neoplasm: Members of FGF family (including FGF1, FGF2, FGF4, FGF5, FGF6, FGF7, and FGF9) were reported to be secreted by CAFs [51,106,107,108] and FGFR2 was shown to be a key mediator of tumor niche-derived signals that are responsible for the acquisition of tamoxifen resistance [51].