Novel partners of S100A8 identified in laryngeal cancer cell lines.

Objective: To explore mechanism of S100A8 in the oncogenesis and development of laryngeal cancer.
Methods: Proteins interacting with S100A8 were isolated from laryngeal cancer cell lines Hep-2 by immunoprecipitation assay with anti-S100A8 antibody. The target bands were cut out and identified by maxtrix assisted laser desorption/ionization time of flight (MALDI-TOF). The peptide mass fingerprinting data of the proteins identified were analyzed based on the Mascot database. The NF-kappa B binding sites of the proteins were predicted by P-Match software. The binding ability of one of the proteins to S100A8 was confirmed by co-immunoprecipitation and immunocytochemistry methods.
Results: Four proteins interacting with S100A8 were obtained, which were hypothetical protein LOC80154, MHC class I HLA-B, similar to T-box 1 isoform C and sarcolemmal associated protein 1. The four genes were predicted to have NF-kappa B binding sites. MHC class I HLA-B, which is one of targets in NF-kappa B pathway, was first confirmed to have the binding ability to S100A8.
Conclusion: The novel partners of S100A8 identified in the study might be involved in NF-kappa B pathway. The binding ability of MHC class I HLA-B to S100A8 implies that S100A8 might function as a new member with other proteins including HLA-B in NF-kappa B pathway. These findings provide a new clue to further study on the molecular mechanism of S100A8 in the genesis of laryngeal carcinomas.