Suppression of cell motility and metastasis by transfection with human motility-related protein (MRP-1/CD9) DNA.
Previously we showed that motility-related protein (MRP-1) is an antigen recognized by monoclonal antibody (mAb) M31-15 inhibiting cell motility and that the sequence of MRP-1 coincides with that of CD9. In the present study, plasmid was constructed in which human MRP-1/CD9 cDNA is expressed under the control of the Abelson murine leukemia virus promoter sequence. The expression plasmid for MRP-1/CD9 was introduced into Chinese hamster ovary cells, human lung adenocarcinoma cell line MAC10 (MRP-1 positive), and human myeloma cell line ARH77 (MRP-1 negative). All of the MRP-1/CD9 (over)expressing clones obtained from these transfected cells showed suppressed cell motility (penetration and phagokinetic track assays) depending on the degree of expression of MRP-1/CD9. Overexpression of MRP-1/CD9 by MAC10 cells resulted in the suppression of cell motility (maximally 73%) associated with considerable inhibition of the cell growth (maximally 48%). However, the inhibition of the growth of MAC10 cells by mAb M31-15 was < 17% at an antibody concentration of 1-5 micrograms/ml, which inhibits cell motility by > 90%. These results suggest that MRP-1/CD9 directly regulates cell motility and may also affect cell growth. Effects on metastasis by the expression of MRP-1 CD9 were investigated with mouse melanoma BL6 cells-BALB/c nu/nu mouse system. Metastatic potential of all transformants expressing MRP-1/CD9 was lower than that of parent BL6 cells.
Ikeyama
S
S
Department VI, Takeda Chemical Industries, Ltd., Osaka, Japan.
Koyama
M
M
Yamaoko
M
M
Sasada
R
R
Miyake
M
M
D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000502:physiology*; D016466:CHO Cells; D002448:Cell Adhesion; D002455:Cell Division; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D006224:Cricetinae; D004247:DNA; D006801:Humans; D008562:Membrane Glycoproteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009362:Neoplasm Metastasis / Q000235:genetics; D010957:Plasmids; D060245:Tetraspanin 29; D014162:Transfection; D014407:Tumor Cells, Cultured
D015703:Antigens, CD; C554869:CD9 protein, human; C554870:Cd9 protein, mouse; D008562:Membrane Glycoproteins; D060245:Tetraspanin 29; D004247:DNA