PHLDA1 and ovarian carcinoma: In our comparison of five different experimental models of ovarian cancer, only 4 of 10 MPAS genes displayed consistent and uniform response to MEK/ERK activity modulations, and only 3 (PHLDA1, EPHA2, and DUSP4) were significantly associated with baseline ERK1/2 activity in both cell lines and patient tissue samples, thereby emphasizing the need to validate gene expression signatures for each type of pathology or condition.