Table I. Proteins annotated as tumor-derived in xenograft-bearing mice.

Identified proteins were divided in two groups: human-specific proteins (identified only in the Human Uniprot database) and homologous proteins (present in both the Human and Mouse Uniprot databases). Further comparison between databases was undertaken and homologous proteins were finally annotated as tumor-derived only in case where their expression was higher in sera of xenotransplated mice by at least 4-fold.