High-throughput computational and experimental biology strategy in identifying tumor expressing CAMs

Organ-specific homing of tumor cells includes receptor-ligand interactions of cell adhesion molecules (CAMs), which stimulate or inhibit the cellular growth. In this report we identified unique CAMs using sequence and pattern analysis with organ-specific peptides as query against mouse genome and proteome sequences. The peptides were seven amino acids in length, and were affinity selected against specific organs utilizing in vivo phage display peptide library in NOD-SCID mice. Various databases were used for the analyses including Local Mouse Cell Adhesion Molecule (LMCAM) database developed by keyword search. Thirty annotated CAMs corresponding to eleven different organ-specific peptides were identified using the bioinformatics analysis. One such identified protein, SEMA5A is reported for the first time to be expressed in human pancreatic cancer cell lines. This combined strategy of experimental and computation biology is an initial approach in identifying novel tumor-specific molecules, thereby paving the way for complete understanding of their role in various processes of tumor metastasis and making organ-specific targeting possible using these peptides.