ASPP2 is a haploinsufficient tumor suppressor that cooperates with p53 to suppress tumor growth.
Vives V., Su J., Zhong S., Ratnayaka I., Slee E., Goldin R., Lu X.
ASPP2 stimulates the apoptotic function of the p53 family in vivo. We show here that ASPP2-/- pups died before weaning. This postnatal lethality was significantly enhanced in p53+/- background and both deletions are synthetic lethal. ASPP2+/- mice developed spontaneous tumors. The tumor onset was accelerated by gamma-irradiation or in p53+/- background. Tumors derived from ASPP2+/- mice retained wild-type ASPP2 allele even though some of them lost p53. These provide the first genetic evidence that ASPP2 is a haploinsufficient tumor suppressor that shares overlapping function(s) with p53 in mouse development and tumor suppression.