The synthetic peptide Gly-Arg-Gly-Asp-Ser (GRGDS) mimics the cellular binding site of many adhesive proteins in the extracellular matrix and causes rounding and detachment of spread cells. The GRGDS (Gly-Arg-Gly-Asp-Ser) peptide has intermediate affinity to V3 and IIb3, which are the integrins most reported to be involved in bone function.