STMN1 (Stathmin, metablastin) is a 17 kDa protein necessary for cell cytoskeleton regulation. It is involved in the regulation of the microtubule filament system via the destabilizion of microtubules. It prevents assembly and promotes the disassembly of microtubules. Additionally, it is involved in the control of learned and innate fear. STMN1 is overexpressed in a variety of cancers, including lung, breast, hepatocellular, esophageal, gastric, pancreatic, endometrial, and colorectal cancer, among others. It is considered a prognostic marker, as high levels of the protein generally correlate with metastasis and lower rates of survival. In immunohistochemistry of normal tissues, STMN1 has cytoplasmic staining in most tissues throughout the body. References: Biochemistry. 1997 Sep 9;36(36):10817-21, PMID: 9312271; Biochemistry. 2005 Nov 8;44(44):14616-25, PMID: 16262261; Journal of Cellular Biochemistry. 2004. 93 (2): 242–50,PMID: 15368352; Proceedings of the National Academy of Sciences of the United States of America. 2008. 105 (38): 14620–5, PMID: 18794533; J Transl Med. 2016; 14: 279, PMID: 27670291; Cell Physiol Biochem. 2018;50(1):66-78, PMID: 30278466