Since S100A4 is expressed in a variety of cell types such as lymphocytes, dendritic cells, macrophages, and smooth muscles (Takenaga et al, 1997b; Rudland et al, 2000), it is important to examine S100A4 expression at the cellular level to ascertain that higher expression of S100A4 mRNA in thyroid carcinoma specimens reflects the expression in thyroid carcinoma cells themselves. Here, S100A4 is linked to thyroid gland carcinoma.