The correlation of the metastatic ability with keratin expression in cultured murine melanoma cell lines, B16-F1 and-F10.

Keratin is an intermediate filament that is a major structural protein of epithelial cells. Until now, the expression of keratin in melanoma cells has not been well understood. Recently, it has been reported that keratin expression is correlated with invasive and metastatic behavior in a variety of cell types. We report keratin expression in cultured murine melanoma cell lines B16-F1 (low incidence of lung colonization) and F10 (high incidence of lung colonization) using an aqueous solution (10 mM Tris-HCl (pH 7.4)/10 mM EDTA/phenylmethyl sulphonyl fluoride (PMSF, 10 micrograms/ml). By comparing these two cell lines, we investigated whether differences in keratin expression can influence the metastatic ability of tumor cell lines in vitro. However, no remarkable differences in keratin expression were found in these cell lines.