The expression profiles of the
erythropoietin producing
hepatocellular carcinoma (
Eph) receptor family of
tyrosine kinases have been previously shown to provide molecular signatures of normal breast cells,
breast tumor cells and invasive
breast carcinoma cells. In particular, the expression of
EphB6 receptor is lost in invasive
breast carcinoma cell line MDA-MB-231. The comparative proteomic profiles of native and EphB6-expressing MDA-MB-231 cells using difference gel electrophoresis (DIGE) and liquid chromatography-mass spectrometry of selected
proteins are presented in this study. The expression of more than 70
proteins was significantly altered in EphB6-transfected MDA-MB-231 cells. These altered
proteins are involved in glycolysis, cell cycle regulation,
tumor suppression, cell proliferation, mitochondrial metabolism,
mRNA splicing, DNA replication and repair. Although the majority of these
proteins have been implicated in
tumorigenesis, the impairment of energy homeostasis and altered regulation of signaling pathways appear to be noteworthy targets of EphB6. Based on the identities of altered
proteins and the pathways regulated by these
proteins, this study suggests that the interactions of EphB6 with a wide variety of
proteins lead to altered proteomic profile of EphB6-transfected MDA-MB-231 cells.