14-3-3sigma, a member of the 14-3-3 family is a putative tumour suppressor gene. It is thought to play a critical role in the G2 check point by sequestering Cdc2-cyclinB11.

Immunohistochemical expression

It is positive in myoepithelial cells of breast. There is frequently loss of expression in breast carcinoma but retention of positivity in metaplastic carcinoma of breast2.

Loss of expression due to hypermethylation appears to be more common in small cell and large cell lung carcinoma than in other types1.

Diagnostic utility



1 Osada H, Tatematsu Y, Yatabe Y, et al. Frequent and histological type-specific inactivation of 14-3-3sigma in human lung cancers. Oncogene 2002; 21:2418-24

2 Leibl S, Gogg-Kammerer M, Sommersacher A, et al. Metaplastic breast carcinomas: are they of myoepithelial differentiation?: immunohistochemical profile of the sarcomatoid subtype using novel myoepithelial markers. Am J Surg Pathol 2005; 29:347-53


This page last revised 27.5.2005.

©SMUHT/PW Bishop