PPP1R13B and breast neoplasm: The expression of ASPP1 and ASPP2 is frequently downregulated in human breast tumours (Samuels-Lev et al, 2001) and tumour cell lines (Liu et al, 2005) expressing wild-type p53, suggesting that there is a selective advantage for loss of ASPP1 and ASPP2 expression in human breast tumours expressing wild-type p53.