The present invention relates to compositions comprising Wnt antagonists and methods of treating Wnt-associated diseases and disorders, such as cancer, inducing differentiation, and reducing the frequency of cancer stem cells, as well as novel methods of screening for such Wnt antagonists. In particular, the invention discloses soluble FZD, SFRP and Ror receptors and their use.本發明關於包含Wnt拮抗劑之組成物及治療與Wnt相關之疾病和病症(諸如癌症)、誘導分化及減少癌幹細胞之發生頻率的方法,以及篩選該Wnt拮抗劑之新穎方法。尤其,本發明揭示可溶性FZD、SFRP和Ror受體及彼等之用途。