Expression and prognostic relevance of activated extracellular-regulated kinases (ERK1/2) in breast cancer

Extracellular-regulated kinases (ERK1, ERK2) are members of the MAPK signaling pathway, which are phosphorylated in response to extracellular stimuli and translocate to the nucleus where they can activate nuclear transcription factors. Although they have been extensively studied in vitro, little is known about their role in the behavior of tumor cells in vivo. In our present study, 148 clinical breast cancer samples (120 cases with follow-up) were studied for expression of ERK1 and ERK2 and their phosphorylated forms (p-ERK1, p-ERK2) by immunoblotting, and p-ERK1/2 expression in the corresponding paraffin sectio…