Optimized Wound Healing Assay to Study Extracellular Vesicle-Driven Glioblastoma Cell Migration

Cell migration is a fundamental process in cancer progression, playing a central role in tumor invasion and metastasis. This highly coordinated behavior is regulated by dynamic interactions between cancer cells and extracellular environment. Among the different tumor types, glioblastoma (GB) represents a particularly aggressive form of cancer in which enhanced migratory capacity is a key determinant of diffuse brain infiltration, tumor recurrence, and poor prognosis. In this context, extracellular vesicles (EVs) have emerged as important mediators, regulating cell migration in several cancer types, including GB. EVs are lipid bilayer-enclosed nano- and micro-sized particles, containing various bioactive molecules that can target specific recipient cells, thereby modulating cellular properties, including the migratory behavior. Among the available methods for studying cell migration, the wound healing assay is the most widely used. Although simple, cost-effective and not requiring sophisticated equipment, its reliability and reproducibility can be affected by technical variability and the diversity of existing protocols. Here, we present an optimized protocol for executing and analyzing a cellular wound healing assay designed to assess EV-mediated migration in GB cells. The protocol incorporates the use of silicone culture inserts to enhance wound homogeneity and reproducibility, together with continuous Mitomycin C incubation to inhibit cell proliferation without inducing cytotoxicity, enabling specific assessment of cell migration. We outline a step-by-step description of the procedure, detailing all required materials and equipment and highlighting critical steps, checkpoints, and key parameters. This method provides a robust framework for reproducible wound healing assays to investigate EV effects on GB cell migration.