Secreted and transmembrane polypeptides and nucleic acids encoding the same

A diagnostic method, comprising determining, in a test biological sample obtained from a mammalian subject, the level of nucleic acid encoding a PRO1280 polypeptide of SEQ ID NO:6 relative to the level of said nucleic acid in a corresponding normal biological sample wherein increased level of said nucleic acid in the test biological sample is indicative that the test biological sample contains cancerous cells.

A diagnostic method comprising determining the expression level of the PRO1280 polypeptide of SEQ ID NO:

• 6 in test biological sample relative to a normal biological sample, wherein overexpression of said polypeptide in the test biological sample is indicative that the sample contains cancerous cells.