PIK3CA and breast cancer: In a recent report, likely driver mutations were newly identified in the exon regions of AKT2, ARID1B, CASP8, CDKN1B, MAP3K1, MAP3K13, NCOR1, SMRCD1, and TBX3 based on analyses of the coding exon regions in 100 primary breast cancers in addition to the mutations previously identified in AKT1, BRCA1, CDH1, GATA3, PIK3CA, PTEN, RB1, and TP5313.