Calponin-1 (EP798Y)

Calponin is a 34 kD polypeptide that interacts with actin, tropomyosin, and calmodulin. It is involved in smooth muscle contraction mechanism and is restricted exclusively to smooth muscle tissue. Anti-calponin has been found to be useful in staining myoepithelium and is, therefore, useful for differentiating benign sclerosing adenosis of the breast from infiltrating ductal carcinoma.1 Calponin positivity has also been noted in malignant myoepithelioma2,5 and pleomorphic adenoma3 of salivary gland origin, as well as angiomatoid malignant fibrous histiocytoma.4