ERBB2 and breast cancer: However, high MPAS in adrenal tumors (Fig. 5a) and in a subset of HER2+ breast tumors (Fig. 5c) correlated with poorer overall survival, again indicating that direct measurement of MAPK signaling output through gene transcription may have prognostic value and, in the case of breast cancer, provide additional insight to the biological context of an already well-defined subtype.