L1CAM Promotes the Infiltrative Properties of Patient-Derived Glioblastoma Cells

Area of Science:

• Neuroscience
• Cancer Biology
• Biophysics

Background:

• L1CAM (an immunoglobulin superfamily member) is crucial for neural development and cell adhesion.
• While L1CAM is linked to glioblastoma (GBM) cell motility, its precise mechanobiological role in patient-derived GBM cells is unclear.
• Understanding L1CAM's function is vital for developing targeted GBM therapies.

Purpose of the Study:

• To investigate the mechanobiological function of L1CAM in patient-derived GBM cell motility.
• To elucidate L1CAM-dependent mechanisms regulating GBM cell adhesion, migration, and infiltration.
• To assess the potential of L1CAM as a therapeutic target for GBM.

Main Methods:

• Established patient-derived GBM cells using the neurosphere method.
• Quantified L1CAM expression via qPCR, Western blotting, flow cytometry, and immunocytochemistry.
• Assessed cell motility using single-cell tracking, functional assays (forced expression, antibody inhibition), adhesion-clutch analysis, and retrograde F-actin flow measurements. In vivo studies involved orthotopic transplantation of L1CAM-overexpressing GBM cells in mice.

Main Results:

• L1CAM-high GBM cells exhibited significantly increased motility on laminin compared to L1CAM-low cells.
• Anti-L1CAM antibodies reduced migration, while L1CAM overexpression enhanced it, confirming L1CAM's pro-motility role.
• L1CAM promoted haptotaxis on laminin and reduced retrograde actin flow, suggesting L1CAM regulates adhesion-clutch dynamics and substrate sensing. In vivo, L1CAM overexpression increased GBM cell infiltration.

Conclusions:

• L1CAM expression on the GBM cell surface is a key regulator of cell motility via adhesion-clutch mechanisms and substrate sensing.
• L1CAM-dependent mechanobiological functions significantly contribute to GBM cell infiltration.
• Targeting L1CAM presents a promising therapeutic strategy to inhibit GBM cell spread and improve treatment outcomes.