Suppressions of metastatic breast cancer invasion and metastasis to brain/cross talk HER2/ERK1/2/MMP-9 signaling pathway

Understanding the molecular pathways that contribute to the development of metastatic breast cancer invasion and metastasis to brain is needed to improve the clinical utility of novel agents, and to predict the success of targeted personalized therapy based on tumor-specific mutations. Little is known about the clinical significance of HER2/ERK1/2/MMP-9 signaling pathway in breast cancer. We performed Global exon array to study the expression of ERK1/2/MMP-9 signaling pathway in metastatic breast cancer to brain, compared its expression in primary breast cancer and breast cancers metastatic to other organs, and validated the findings by RT-PCR. Immunohistochemistry was performed to study the expression and localization of ERK1/2/MMP-9 proteins in primary and metastatic breast cancer tissues and breast cancer cell lines. We performed matrigel invasion, transendothelial migration and membrane potential assays in established lines of normal breast cells.