Identification of the motility-related protein (MRP-1), recognized by monoclonal antibody M31-15, which inhibits cell motility.

Abstract

SummaryA murine monodonal antibody (M31-15) was identified using the penetration-inhibiting assay of a human lung adenocarcinoma cell line (MAC10) and remarkably inhibited the phagokinetic tract motility of various cancer cell lines. The antigen, motility-related protein (MRP-1), recognized by M31-15, was 25-and 28-kD proteins, and M31-15 was used to isolate a cDNA clone from a human breast carcinoma cDNA library. Sequence analysis revealed that MRP-1 had strong similarity with a B cell surface antigen (CD37), a melanoma-associated antigen (ME491), the target of an antiproliferative antibody (TAPA-1), a human tumor-associated antigen (CO-029), and the Sm23 antigen of the trematode parasite Schistosoma mansoni.C ell motility is a highly complex process dependent on pericellular adhesion molecules such as fibronectin (FN) 1 and laminin, their integrin receptors, cytoskeletal components, and a junctional unit connecting cytoskeletal components and membrane receptors (1, 2). Involvement of the cell-binding and Hep-2 domains of FN and integrin receptor in determining cell motility for certain types of cells has become increasingly clear (3). In addition, a large variety of growth factors and autocrine factors have been shown to stimulate cell motility (4). There has been little attention paid to carbohydrates that modulate cell motility despite the fact that cell surface proteins and lipids are heavily glycosylated. Recently, we (5) showed that two independent mAbs directed to a common carbohydrate structure, Fuca 1-2Galfll-K, dramatically inhibited the motility of various cancer cell lines and metastasis of BL6 (6), highly metastatic variants of mouse melanoma B16. To identify cell surface molecules involved in the control of cell motility, we described a new approach based on: (a) selection of a few lines showing high motility out of a large number of human tumor cell lines; (b) immunization of mice with the high-motility cell lines and selection of mAbs showing inhibition of cell motility in polycarbonate membrane penetration assay; and (c) characterization of the epitope defined by motility-inhibiting mAbs. This procedure has led us to an interesting mAb, M31-15, which recognized 25-and 28-kD cell surface proteins called motility-1 Abbreviations used in this paper: FN, fibronectin; MRP-1, motility related protein.related protein (MRP-1). A cDNA clone for MRP-1 was isolated from a human breast carcinoma cDNA library with this antibody, and the amino acid sequence of MRP-1 was predicted from the cDNA sequence. Materials and MethodsDetermination of CellMotility. Cell motility was determined by two assay systems, cell penetration (5) and phagokinetic track (7). In the former system, cell migration was determined through a polycarbonate membrane assembly based on a Boyden chamber (1,8). The assembly (Transwell) was purchased from Costar (Cambridge, MA) with defined pore size (3-, 5-, and 8-#m diameter). Briefly, 100-/zl hybridoma supernatant containing a known concentration of mAb was mixed with 600 #1 of culture medi...

Motility-related protein (MRP-1/CD9) and KAI1/CD82 expression inversely correlate with lymph node metastasis in oesophageal squamous cell carcinoma

“…One of those factors, cell motility, plays an important role in the progression, especially after the extravasation. Motility-related protein 1 (MRP-1/CD9), which belongs to the transmembrane 4 superfamily of membrane proteins, is considered to inhibit cell motility (Miyake et al, 1991). It has been demonstrated that the cells which expressed MRP-1/CD9 by transfection showed suppressed cell motility in vitro (Ikeyama et al, 1993).…”

The tetraspanin CD9 inhibits the proliferation and tumorigenicity of human colon carcinoma cells

“…5,7,9,10 mAbs directed to the CD9 molecule have also been shown to inhibit the migration of different types of carcinoma tumor cells and the transendothelial migration of melanoma cells. [11][12][13] Therefore, the inverse correlation observed between CD9 expression and the metastatic potential could be explained, at least in part, by the effects mediated by CD9 on cell adhesion and migration through the interactions among this tetraspanin and different integrins. 2,3 We have recently described a functional conformation of CD9, detected by the anti-CD9 mAb PAINS-13, that is imposed upon association of this tetraspanin with members of the beta-1 subfamily of integrins and particularly with a6b1, a cellular adhesion receptor for laminin.…”

Inhibition of hepatocyte growth factor-induced motility and in vitro invasion of human colon cancer cells by gamma-linolenic acid

“…The possibility of anti-invasion and anti-motility strategies may have important implications for cancer management. In the past few years, various agents have been shown to possess anti-invasion and anti-metastasis properties; among these are Arg-Gly-Asp (RGD) sequence peptides and motility-regulating factors (Miyake et al, 1991;Mohler et al, 1992;Isoai et al, 1993). Although essential fatty acids have previously been shown to inhibit cancer cell growth after relatively prolonged incubation, the effect of essential fatty acids on cancer cell motility and invasion have not been previously reported.…”