The present invention relates to methods and compositions for the treatment and diagnosis of cellular proliferative disorders, including, but not limited to, lung, breast, ovary, and colon tumors. The invention further provides methods for identifying a compound capable of treating a cellular proliferative disorder or modulating tumorigenesis. The invention also provides a method for modulating tumorigenesis, e.g., modulating tumorigenesis in a subject. In addition, the invention provides a method for treating a subject having a cellular proliferative disorder characterized by aberrant 32222 polypeptide activity or aberrant 32222 nucleic acid expression.