Abstract: This invention relates to methods of determining the prognosis of a subject with a Pin1 associated disorder by evaluating the levels of phosphorylated Pin1 in a biological sample. The invention also provides Pin1 polypeptides phosphorylated position 16, position 71, or both. The invention further relates to a crystal structure of a pPin1(71) polypeptide and a pPin1(16)(71) polypeptide. The invention also provides constitutively active mutants of Pin1 and modulators that are specific for the molecules. The invention further provides methods for determining if a subject is at risk of developing a Pin1 associated state by determining if a the subject has a mutation in Pin1 that renders the polypeptide constitutively active.