SM Myosin

Formalin-fixed, paraffin embedded tissue block or cell block, or 1 unstained charged slide for each test requested plus 3-4 additional unstained slides cut at 4 microns. Adequate space on each slide for control tissue is required.

SM-MHC is a cytoplasmic structural protein, which is a major component of the contractile apparatus in smooth muscle cells. It has been used as a marker for smooth muscle differentiation, but it is most useful as a marker of myoepithelial cells of breast, in the distinction of invasive carcinoma from in situ lesions or other benign mimickers, preferrably with p63 and calponin as a panel of antibodies.