PPM1D and breast neoplasm: Our systematic study revealed eleven genes (FAM33A, DHX40, CLTC, PTRH2, TMEM49, TUBD1, RPS6KB1, ABC1, USP32, APPBP2, PPM1D) that showed significantly (P<0.01) higher expression levels in primary breast tumours with high level 17q23 amplification compared to tumours without amplification.