Expression of 14-3-3 sigma protein in normal and neoplastic canine mammary gland.

摘要

14-3-3 sigma protein is a negative cell cycle regulator, with both reduced and elevated levels associated with cancer in humans. This study assessed the expression of this protein in canine mammary tissues using immunohistochemistry and Western blotting. 14-3-3 sigma was detected in 97% of the mammary tissue samples examined and was found in both myoepithelial (MECs) and epithelial (ECs) cells. Expression levels were elevated and reduced in neoplastic ECs and MECs, respectively (P<0.001). Intense expression of 14-3-3 sigma was detected in neoplastic ECs infiltrating blood vessels and lymph nodes and suggests a possible role for this protein in the malignant transformation of mammary neoplasms. Moreover, double immunostaining for 14-3-3 sigma and the MEC - specific marker p63, confirmed that 14-3-3 sigma is a highly sensitive marker of MECs since all p63 - positive cells were also positive for 14-3-3 sigma . However, this protein is not exclusive to MECs as ECs also labelled positively.Digital Object Identifier http://dx.doi.org/10.1016/j.tvjl.2010.12.015