Serpin peptidase inhibitor, clade B (ovalbumin), member 6 (SERPINB6)

Serpin peptidase inhibitor, clade B (ovalbumin), member 6 (SERPINB6), also known as serpin B6 or PI-6, is an intracellular serine protease inhibitor belonging to the serpin superfamily, specifically the ovalbumin (clade B) family. SERPINB6 plays a protective role in specialized cells by preventing inappropriate proteolytic activity, especially by inhibiting serine proteases such as cathepsin G, kallikrein-8, and thrombin. In the inner ear, SERPINB6 protects sensory hair cells from stress-induced leakage of lysosomal proteases; loss-of-function mutations result in vulnerability to proteolytic injury, leading to sensorineural hearing loss (DFNB91). It is also involved in regulation of protease activity in mast cells and keratinocytes, contributing to immune and inflammatory responses. Altered expression is observed in colorectal cancer and during gonadal development. No approved drugs directly target SERPINB6; its primary significance is in genetic disease (DFNB91) and potential as a cancer biomarker.

Other names

PI-6PI6PTICAPCytoplasmic antiproteinasePeptidase inhibitor 6Placental thrombin inhibitorDFNB91MSTP057SPI3serpin B6cytoplasmic antiproteinaseprotease inhibitor 6 (placental thrombin inhibitor)serine (or cysteine) proteinase inhibitor, clade B (ovalbumin)serpin peptidase inhibitor, clade B (ovalbumin), member 6

Not established for drugs (most data relate to endogenous inhibitory mechanisms: inhibition of specific serine proteases)