The Wnt signaling pathway is implicated in a variety of biological processesranging from developmental cell fate to human disease.The components involvedin Wnt signaling have been under intense investigation over the last 2 decades.Aberrant canonical Wnt activation has been linked to tumor formation andinvolves activation of effector molecules or loss of tumor suppressor function.Secreted frizzled-related proteins (sFRPs) are Wnt antagonists.In recent years,accumulating evidence has suggested that sFRPs act as tumor suppressorsbecause their expression is frequently silenced in cancer by promoter hypermethyla-tion.However,sFRPs may also promote cell growth in some contexts.Here,wefocus on the known knowledge of sFRPs in tumorigenesis. The Wnt signaling pathway is implicated in a variety of biological processes drawing from developmental cell fate to human disease. The components involved in Wnt signaling have been under intense investigation over the last 2 decades. Aberrant canonical Wnt activation has been linked to tumor formation and involves activation of effector molecules or loss of tumor suppressor function. Secreted frizzled-related proteins (sFRPs) are Wnt antagonists. In recent years, accumulating evidence has suggested that sFRPs act as tumor suppressors have their expression is often silenced in cancer by promoter hypermethylase. However, sFRPs may also promote cell growth in some contexts. Here, wefocus on the known knowledge of sFRPs in tumorigenesis.