CLDN2 and adenocarcinoma: RT-PCR confirmed that amphiregulin (Areg), epiregulin (Ereg), fetuin beta (Fetub), claudin 2 (Cldn2), hepatic nuclear factor 4, alpha (Hnf4α), glutathione S-transferase, alpha 4 (Gsta4) and forkhead box A3 (Foxa3) were up-regulated in adenocarcinoma (Supplementary Figure S3 and S4).