Background：

Members of the ’frizzled’ gene family encode 7-transmembrane domain proteins that are receptors for Wnt signaling proteins. The FZD7 protein contains an N-terminal signal sequence， 10 cysteine residues typical of the cysteine-rich extracellular domain of Fz family members， 7 putative transmembrane domains， and an intracellular C-terminal tail with a PDZ domain-binding motif. FZD7 gene expression may downregulate APC function and enhance beta-catenin-mediated signals in poorly differentiated human esophageal carcinomas.