FGFBP1 and squamous cell carcinoma: HBp17, which originally copurified with FGF-2 from medium conditioned by A431 human epidermoid carcinoma cells, was shown to bind both FGF-1 and FGF-2 in a noncovalent and reversible manner, and based on this property it was predicted to regulate the extracellular availability and biological activity of FGFs (Wu et al. 1991; Yoshimura et al. 1998; Harris et al. 2000; Lametsch et al. 2000).