SERPINB3 (OTI3G4) Mouse Monoclonal Antibody #90624

Serpin family B member 3 (SERPINB3), also known as squamous cell carcinoma antigen 1 (SCCA1), belongs to the serpin family and inhibits papain-like cysteine proteases (1). SERPINB3 is unique to the other serpins, as it lacks inhibitory activity against serine proteases but has inhibitory activity against papain-like cysteine proteases cathepsins K, L, and S (1,2). It may function as an inhibitor to modulate the host immune response against tumor cells and can act as a UV-induced apoptosis inhibitor by suppressing the activity of c-Jun NH2-terminal kinase 1 (JNK1) (1,3). SERPINB3 is expressed in normal squamous epithelium and in several organs, including tongue, esophageal, uterine, cervical, and vaginal epithelium. It is also expressed in Hassall’s corpuscles of the thymus and some areas of the skin (4). SERPINB3 has been found to be overexpressed and implicated in several types of cancer, including hepatocellular carcinoma (HCC), lung, ovarian, and breast cancer (5-8). It is also overexpressed and implicated in hepatoblastoma, autoimmune disorders, lung fibrosis, cholesteatoma, and skin disease (9-13).