Phosphoproteome of cRGD-induced MCF-7 cell death

The RGD (arginine-glycine-aspartate) motif is an integrin-recognition motif found in many ligands, so that RGD-containing peptides can interact with the integrin receptor to induce cell-signaling processes and influence many different diseases. Synthetic peptides containing the RGD motif have been used extensively as inhibitors of integrin-ligand interactions in studies of cell growth, death, adhesion, migration, and invasion. Therefore, we designed a cyclic-RGD peptide (Tpa-RGDWPC, cRGD) with rigid skeleton to closely bind with its receptor. According to previous reports that cRGD can cause cell death in MCF-7 breast cancer cell line. We are interested in what molecular mechanism underlies the cRGD exerts on MCF-7 cells. Depending on protein phosphorylation, it is a major post-translational modification connected to the signaling pathways in the cell. We used the proteomics with Pro-Q Diamond phosphoprotein dye technology to survey the global changes in phosphoproteins after cRGD treatment in MCF-7 cells. In this report, we find some phosphoproteins play important roles in cRGD treated MCF-7 cell death and provide a valuable in-depth insight into its use in breast cancer therapy.