Anaphase-promoting complex subunit 8 (APC8, CDC23) is a component of the tetratricopeptide repeat (TPR) APC/C sub-complex that also includes APC3 (CDC27) and APC6 (CDC16). APC8 protein associates with APC3 and APC6 to facilitate recruitment of the APC/C coactivation subunits CDC20 and Cdh1/FZR1. Research studies suggest that APC8 protein is overexpressed in papillary thyroid cancer and acts as an important regulator of cell cycle progression and cell growth.