FGFR1 and breast cancer: For example, fibroblast cell surface-associated fibroblast growth factor (FGF)-2 was shown to induce the cell-contact-dependent migration and invasion of colorectal cancer cells via the activation of the FGF-2-FGFRs-SRC-αvβ5 integrin axis [37], whereas the activation of FGF-2/FGFR-1 paracrine signaling in breast cancer cells induces the expression of the connective tissue growth factor (CTGF), thereby promoting the migration and invasion of tumor cells [38].