ETV4 and Barrett esophagus: The majority of adenocarcinomas showed enhanced levels of MMP-1 (Additional file 1: Figure S2A) and/or MMP-7 (Additional file 1: Figure S2B) whereas only a few samples from normal oesophageal epithelium or from patients with Barrett's metaplasia showed enhanced levels of expression of either MMP. The data were then compared to the expression of PEA3 and ER81 in the same samples (Figure 6A).