Laminin-1-induced migration of multiple myeloma cells involves the high-affinity 67 kD laminin receptor

Area of Science:

• Cell Biology
• Oncology
• Biochemistry

Background:

• The 67 kD laminin receptor (67LR) is known to bind laminin-1 (LN), a key component of the basement membrane.
• Multiple myeloma (MM) is a cancer of plasma cells, and understanding cell migration is crucial for disease progression.

Purpose of the Study:

• To investigate the expression of 67LR in multiple myeloma cells and its role in cell migration.
• To determine if laminin-1 (LN) acts as a chemoattractant for MM cells via 67LR.

Main Methods:

• Assessed 67LR expression on human multiple myeloma cell lines (HMCL) and murine 5T2MM cells.
• Examined 67LR expression on CD38(bright+) plasma cells from MM bone marrow (BM) samples before and after co-culture with BM endothelial cells.
• Stimulated in vitro migration of MM cells with LN and assessed the effect of a 67LR-binding peptide (peptide 11) and blocking antiserum.
• Evaluated the in vivo homing of 5T2MM cells to the BM compartment in a murine model after co-injection with peptide 11.

Main Results:

• Human multiple myeloma cell lines and murine 5T2MM cells express 67LR.
• LN significantly stimulated the in vitro migration of various MM cells, including primary cells.
• Blocking 67LR with peptide 11 or antiserum partially inhibited MM cell migration.
• In vivo, peptide 11 reduced the homing of 5T2MM cells to the BM compartment in a murine model.

Conclusions:

• Laminin-1 (LN) functions as a chemoattractant for multiple myeloma (MM) cells through interaction with the 67 kD laminin receptor (67LR).
• This LN-67LR interaction may play a significant role in the extravasation process of circulating MM cells.
• Targeting the 67LR-LN interaction could be a potential therapeutic strategy for MM.