PIN1 and neoplasm: Reinforcing this circuitry, the death associated protein kinase 1 (DAPK1), a tumor suppressor found hypermethylated in tumors and a crucial inhibitor of Pin1 isomerase activity (Lee et al, 2011), was shown to be repressed by N1-ICD (Li et al, 2008), delineating a possible scenario in which N1-ICD boosts not only expression but also activity of Pin1.