Abstract: The present invention provides agents, such as soluble receptors, antibodies, and small molecules that modulate the immune response. In some embodiments, the agents activate or increase the immune response to cancer and/or a tumor. In some embodiments, the agents inhibit or suppress the immune response to cancer and/or a tumor. The invention also provides compositions, such as pharmaceutical compositions, comprising the agents. The invention further provides methods of administering the agents so a subject in need thereof. In some embodiments, the invention provides methods of using the agents for cancer immunotherapy. In some embodiments, the invention provides methods of using the agents for treatment of autoimmune diseases.

Abstract: The present invention relates to compositions and methods for characterizing, diagnosing, and treating cancer. In particular the invention provides the means and methods for the diagnosis, characterization, prognosis and treatment of cancer and specifically targeting cancer stem cells. The present invention provides a soluble FZD receptor comprising an extracellular domain of a human FZD receptor that inhibits growth of tumor cells. The present invention still further provides a soluble receptor comprising a Fri domain of a human FZD receptor that binds a ligand of a human FZD receptor and said soluble receptor is capable of inhibiting tumor growth. The present invention still further provides a method of treating cancer comprising administering a soluble FZD receptor comprising for example, either an extracellular domain of a human FZD receptor or a Fri domain of a human FZD receptor, in an amount effective to inhibit tumor growth.

Abstract: Novel anti-cancer agents, including, but not limited to, antibodies and other polypeptides, that bind to human frizzled receptors are provided. Novel epitopes within the human frizzled receptors which are suitable as targets for anti-cancer agents are also identified. Methods of using the agents or antibodies, such as methods of using the agents or antibodies to inhibit Wnt signaling and/or inhibit tumor growth are further provided. Screening methods are also provided.