PIK3CA and breast cancer: We assembled a panel of cell lines from our PIK3CA‐H1047R mouse mammary tumors, generated human HS578T‐H1047R and ‐E545K breast cancer cell lines, and obtained cell lines derived from recurrent H1047R mouse tumors (RDR‐C234 and RDR‐A677) (Liu et al., 2011).