Disclosed herein are PACE4 inhibitors, compositions comprising PACE4 inhibitors and their uses thereof for lowering PACE4 activity, reducing cell proliferation, reducing tumor growth, reducing metastasis formation, preventing and/or treating cancer. Also provided are methods for lowering PACE4 activity, reducing the proliferation of a cell, reducing tumor growth and/or treating and preventing cancer. Methods for screening PACE4 inhibitors and cell proliferation inhibitors are further provided.
