CD44v3,8-10 is involved in cytoskeleton-mediated tumor cell migration and matrix metalloproteinase (MMP-9) association in metastatic breast cancer cells

Abstract

In the present study, we have employed a unique breast cancer cell line (Met-1, which was derived from a high metastatic potential tumor in transgenic mice expressing polyomavirus middle T oncogene) to study the role of CD44 variant isoform(s) in the regulation of metastatic breast tumor cell behavior. The results of reverse transcriptase-polymerase chain reaction, Southern blot, nucleotide sequencing, immunoprecipitation, and immunoblot analyses indicated that these cells express a major CD44 isoform (molecular weight approximately 260 kDa) containing a v3,8-10 exon insertion (designated as CD44v3,8-10). In addition, we have determined that CD44v3,8-10 binds specifically to the cytoskeletal proteins such as ankyrin. Biochemical analyses, using competition binding assays and a synthetic peptide identical to NGGNGTVEDRKPSEL (a sequence located between aa480 and aa494 of CD44v3,8-10) indicate that this 15-amino acid peptide binds specifically to the cytoskeletal protein ankyrin (but not to fodrin or spectrin). This peptide competes effectively for ankyrin binding to CD44v3,8-10. Therefore, we believe that the sequence 480NGGNGTVEDRKPSE494L, located at the cytoplasmic domain of CD44v3,8-10, is required for the ankyrin binding. We have also detected that CD44v3,8-10-containing Met-1 cells are capable of forming membrane spikes or "invadopodia" structures and undergo active migration processes. Treatments of Met-1 cells with certain agents including anti-CD44v3 antibody, cytochalasin D (a microfilament inhibitor), and W-7 (a calmodulin antagonist), but not colchicine (a microtubule disrupting agent) effectively inhibit "invadopodia" formation and subsequent tumor cell migration. Further analyses using zymography assays and double immunofluorescence staining indicated that CD44v3,8-10 is closely associated with the active form of matrix metalloproteinase, MMP-9, in a complex within "invadopodia" structures. These findings suggest that CD44v3,8-10 plays an important role in linking ankyrin to the membrane-associated actomyosin contractile system required for "invadopodia" formation (coupled with matrix degradation activities) and tumor cell migration during breast cancer progression.

A Fermented Ginseng Extract, BST204, Inhibits Proliferation and Motility of Human Colon Cancer Cells

“…Both MMP-2 and/or MMP-9 are associated with tumor metastatic processes, and the more malignant tumors generally have the more potent MMP-2 and/or MMP-9 activity in stimulating metastasis of tumors (Bourguignon et al, 1998;Shamamian et al, 2001). In addition, different kinds of kinases of cell signal pathways such as PI3K and MAPKs are known to be involved in MMP activation and cancer cell invasion (Tanno et al, 2001;Cho et al, 2007;Bocca et al, 2009).…”

Clinicopathological Significance of Expression of CD44 Variants in Head and Neck Squamous Cell Carcinoma

“…Moreover, it was recently reported that CD44 regulates signal transduction, including cell-cell and cellmatrix interactions. 29,30) Takahashi et al 31) reported that cell invasion and cell migration were enhanced after the treatment of melanoma cells with a monoclonal antibody to CD44 and the up-regulation of matrix metalloproteinases. We therefore consider that loss or dysfunction of CD44 may play an important role in cancer invasion or metastasis.…”

Gelatinase-mediated migration and invasion of cancer cells

“…The interaction mechanism of CD44 with MMP-9 is not known, however, MT1-MMP utilizes the hemopexin-like domain for its interaction with CD44 (Mori et al, 2002). MMP-9 interacts with CD44 in invadopodia (Bourguignon et al, 1998). These are the same cellular structures, which also contain MMP-2 and α V β 3 complexes (Deryugina et al, 2001) together with MT1-MMP (Nakahara et al, 1997).…”