>The idea was to use it instead of actin to 
>demonstrate myoepithelial cells in breast 
>carcinoma to determine invasiveness, 
>but since we brought it on board, 
>nobody has ordered it.

For myoepithelial cells, CD10 also works nicely.

See also: 
Moritani S, Kushima R, Sugihara H, Bamba M, Kobayashi TK, Hattori T.
Availability of CD10 immunohistochemistry as a marker of breast
myoepithelial cells on paraffin sections.
Mod Pathol. 2002 Apr;15(4):397-405.

Gusterson BA, Monaghan P, Mahendran R, Ellis J, O'Hare MJ.
Identification of myoepithelial cells in human and rat breasts by
anti-common acute lymphoblastic leukemia antigen antibody A12.
J Natl Cancer Inst. 1986 Aug;77(2):343-9.

Alexander Nader MD
Vienna, Austria