The role of S100A4 gene encoding an S100-related calcium-binding protein in human bile duct adenocarcinoma cell lines: Correlation of S100A4 expression and invasive growth in Matrigel Matrix

S100A4, one of the tandemly arranged S100 genes at chromosome 1q21, has been suggested to play a functional role in cell motility and invasiveness of tumor cell growth. We investigated the expression of S100A4 and the in vitro invasiveness of 4 human bile duct adenocarcinoma cell lines by the Matrigel assay. S100A4 was abundantly expressed in 2 adenocarcinoma cell lines whose growth pattern was highly invasive. Induction of antisense S100A4 into one of the cell lines decreased S100A4 mRNA levels and reduced invasiveness. In contrast, induction of sense S100A4 expression into non-invasive KMBC adenocarcinoma cells, which originally lacked S100A4 expression, resulted in apparent invasive potential in the transfected cells compared with the cells with the vector alone. These results suggest that S100A4 expression is well correlated with the invasiveness of human bile duct adenocarcinomas.