S100A8 and carcinoma: In our experiments, the effect on carcinoma growth could not be attributed to extracellular S100A8/A9 protein since S100A8/A9 released into the medium from TR146 or transfected KB cells is below the limits of detection (data not shown) and sequence analysis of S100A8 and S100A9 genes shows no upstream signal peptides, which are required for canonical secretion.