The zinc finger E-box binding homeobox transcriptional repressor ZEB1 is differentially expressed in the metastases of patients with breast cancer.
Metastasis is a major problem in patients with breast cancer (1). We analyzed published microarray (2) and multiplexed mRNA quantification (3) datasets to identify transcription factors whose expression changed most significantly between primary tumors in patients with breast cancer and metastatic tissues. We identified ZEB1 as differentially expressed when comparing the transcriptomes of primary tumors of the breast to the metastases they generate (2). Analysis of a separate multiplexed mRNA quantification dataset uncovered similar differential expression of ZEB1 in metastases compared to primary breast tumors (3). ZEB1 expression has been reported as important for metastases and for the epithelial to mesenchymal transition in cancer (4-9); we found in this study, however, that ZEB1 was expressed at significantly lower levels in metastases across tissue type when compared to primary breast tumors.