Differential regulation of vimentin mRNA by 12-O-tetradecanoylphorbol 13-acetate and all-trans-retinoic acid correlates with motility of Hep 3B human hepatocellular carcinoma cells

Vimentin is a growth-related gene and often expressed when epithelial cells are stimulated to proliferate by growth factors. In cancer, vimentin expression is associated with a dedifferentiated malignant phenotype, increased motility, invasive ability and poor prognosis. We studied the regulation of vimentin mRNA and multistep invasion processes following treatment of 12-O-tetradecanoylphorbol 13-acetate (TPA) and all-trans-retinoic acid (RA) in Hep 3B hepatocellular carcinoma cells. TPA showed marked induction of vimentin mRNA, while RA decreased the mRNA level. TPA or RA did not affect cell proliferation, cell-matrix protein adhesion, and matrix metalloproteinases and urokinase plasminogen activator activities. In vitro invasion ability was significantly increased or decreased with TPA or RA treatment, paralleled to the in vitro motile activity, respectively. These findings suggest that TPA and RA could modulate the invasive potential of Hep 3B cells by altering cellular motility related to differential regulation of vimentin mRNA.