FZD7 and breast cancer: Among the FZD family, FZD7 appears to be the most important Wnt receptor involved in cancer development and progression, and FZD7 is most commonly up-regulated in a variety of cancers, including colorectal cancer [40], HCC [24], esophageal cancer [41], breast cancer [42], lung cancer [43], Wilm's tumor [44], gastric cancer [45] and melanoma [43].