This invention describes compositions related to growth inhibitory protein-derived peptide fragments. These fragments can be identified by several methods including homology comparison and amino acid pairing techniques. Certain fragment sequences have been shown to provide homology to various biological activities and are contemplated as potential therapeutic agents. These biological activities include, but are not limited to, anti-cancer effects, nonselective calcium channel regulation, angiogenesis inhibition, cytoskeletal controls, cell cycle regulation, enzyme function, transcription, and anti-microbials.