Recent studies have shown that cytoplasmic mislocalization of p27 occurs in many cancers; whereas loss of nuclear p27 or a gain of cytoplasmic p27 can be associated with poor prognoses (Denicourt et al., 2007; Fukumoto et al., 2004; Liang et al., 2002; Rosen et al., 2005; Singh et al., 1998). The gene discussed is CDKN1B; the disease is cancer.