Regulation of cell motility via high and low affinity autocrine motility factor (AMF) receptor in human oral squamous carcinoma cells.

A tumour-secreted cytokine autocrine motility factor (AMF) induces in vivo invasion and metastasis, and in vitro tumour cell motility by a signal transduction through interaction with its cell surface receptor gp78. In this report, we investigated the characterization of a high-metastatic human oral squamous cell carcinoma (SCC) cell line LMF4 and low-metastatic HSC-3 in comparison with non-metastatic HSC-2 and HSC-4. Morphological and motility analyses revealed LMF4 cells to have the highest motile activity among those cells. However, LMF4 cells shared the similar features with HSC-3: high level secretion of AMF, enhancement of gp78 expression, co-expression of vimentin and cytokeratin, although LMF4 cells showed twice as high motile reactivity as HSC-3. The only difference was that LMF4 had twice as high amount of low-affinity receptor(s) as HSC-3, shown by Scatchard analysis.