DBN1 (drebrin 1) encodes an actin-binding protein that plays critical roles in cellular organization and disease pathogenesis. The protein exists in two major isoforms: drebrin A (neuron-specific, containing the Ins2 sequence) and drebrin E (more widely distributed), produced by alternative splicing from a single gene 1. In normal physiology, DBN1 is highly concentrated in dendritic spines where it regulates synaptic activity and creates unique F-actin platforms for molecular assembly 1. However, DBN1 demonstrates significant pathological roles across multiple diseases. In cancer, DBN1 disrupts the NF2-LATS kinase complex by competing for NF2 binding, leading to YAP activation and promoting liver tumorigenesis 2. DBN1 facilitates cancer cell migration and invasion through GAB2 upregulation and activation of PI3K/AKT and MAPK/ERK signaling pathways 3. In leukemia, physical interaction between BAALC and DBN1 promotes cell adhesion to bone marrow stromal cells, contributing to chemotherapy resistance 4. Paradoxically, downregulation of DBN1 is associated with vincristine resistance in colon cancer 5. Additionally, DBN1 phosphorylation at S142 is negatively correlated with magnesium content in colorectal cancer, where this modification enhances cell migration through MMP2 upregulation 6. These findings establish DBN1 as a multifunctional protein with both physiological and pathological significance.