APC and cancer: Immunostaining for MOAP-1 in several cancer cell lines illustrated that, under normal physiological conditions, the intracellular abundance of MOAP-1 is maintained at low levels as a result of its constitutive degradation by the ubiquitin-proteasome system (6) with APC/Ccdh1 (7) similar to APC/Ccdc20-directed ubiquitination of RASSF1A during mitosis (38, 44).