L1CAM encodes a neural cell adhesion molecule critical for nervous system development and function. During brain development, L1CAM is essential for neuronal migration, axonal growth and fasciculation, and synaptogenesis 1. Mutations in L1CAM cause X-linked neurodevelopmental disorders including hydrocephalus, spastic paraplegia, and mental retardation 1. The protein functions through cell-cell and cell-matrix adhesion mechanisms, facilitating axon guidance and synaptic plasticity in mature neurons 2. Beyond its neural roles, L1CAM has emerged as a critical factor in cancer metastasis. It is not expressed in normal intestinal epithelium but becomes induced during tissue regeneration and is required for colorectal cancer propagation and liver metastasis 3. L1CAM enables disseminated cancer cells to spread on capillaries in a pericyte-like manner, activating YAP and MRTF mechanotransduction pathways essential for metastatic colonization 4. The protein promotes cancer cell motility, invasion, and chemoresistance across multiple cancer types 5. L1CAM has shown promise as both a prognostic biomarker and therapeutic target in oncology, while also serving as a marker for neuron-derived extracellular vesicles in biofluid analysis 6.