STMN1 (stathmin 1) is a microtubule-destabilizing phosphoprotein that regulates microtubule dynamics by promoting depolymerization and inhibiting assembly 1. Phosphorylation at Ser16 and Ser38 modulates its activity 2, with implications for neuronal development and cytoskeletal organization. Mechanistically, STMN1 functions through multiple pathways. It directly destabilizes microtubules by reducing α-tubulin acetylation 1, while also activating non-microtubule-dependent signaling, including the p38MAPK/STAT1 pathway 2. STMN1 can be stabilized through phosphorylation by PP1-mediated mechanisms 1 and regulated via the STMN1-IGFBP5 axis 3. It also participates in mRNA export regulation affecting expression of chemotherapy-resistance genes 4. STMN1 elevation associates with poor cancer prognosis across multiple malignancies. High STMN1 correlates with aggressive features in esophageal cancer, including increased metastasis and clinical grade 5. In triple-negative breast cancer, STMN1 promotes cell proliferation, migration, and paclitaxel resistance 1. Similarly, in non-small cell lung cancer and hepatocellular carcinoma, STMN1 overexpression drives metastasis and poor outcomes 2, 6. In intervertebral disc degeneration, STMN1 induces cellular senescence and extracellular matrix degradation 3. Clinically, STMN1 represents a promising therapeutic target. Inhibiting STMN1 phosphorylation via MEK/ERK pathway suppression showed 71% tumor growth reduction 7, while targeting upstream regulators like RNF31 resensitized paclitaxel-resistant tumors 4.