Smoothelin (SMTN)

Smoothelin is a structural protein encoded by the SMTN gene, expressed exclusively in terminally differentiated, contractile smooth muscle cells, where it forms part of the cytoskeleton and associates with stress fibers[1][2][3][6]. It is highly specific to contractile smooth muscle, not found in proliferative smooth muscle or myofibroblasts, and plays a critical role in maintaining the contractile phenotype and cytoskeletal integrity of these cells. Smoothelin is routinely used as a highly specific immunohistochemical marker in diagnostic pathology to differentiate smooth muscle neoplasms and assess muscle layer involvement in tumors, particularly in the bladder and gastrointestinal tract[1]. Genetically, alterations or specific haplotypes in SMTN have been associated with vascular and fibrotic diseases, including essential hypertension and myocardial or cerebral infarction, indicating a physiological relevance to vascular health and potential involvement in disease mechanisms[1][3]. However, smoothelin lacks enzymatic, receptor, transporter, or transcription factor activity and is not considered a direct therapeutic target.

Other names

SmoothelinSMTNSMSMOsmoothelin