The Expression of STAT3 in Skin Tumors

Kwon, Hyuk; Park, Younglip; Lee, Sung Yul; Lee, Jongsuk; Whang, Kyu Uang

Abstract

BACKGROUND
Signal transducers and activators of transcription (STAT) proteins are a family of latent cytoplasmic transcription factors that are expressed in many cell types and they regulate the transcription of a broad spectrum of genes that are critically involved in cytokine signaling, cell proliferation and development. Among them, STAT3 has been most strongly implicated in tumorigenesis.
OBJECTIVE
This study was designed to measure the expression of STAT3 in different skin tumors.
METHODS
The expression of STAT3 was examined by immunohistochemical staining of 61 specimens of skin tumors; 15 cases of seborrheic keratosis, 15 cases of keratoacanthomas, 18 cases of basal cell carcinomas (BCC) and 13 cases of squamous cell carcinomas (SCC).
RESULTS
Immunohistochemical analysis of the 61 skin tumor tissue samples revealed a high expression of STAT3 in the SCCs, which are the more dysplastic and invasive skin tumors. Keratoacanthomas and BCCs showed a mild to moderate expression of STAT3 and a low expression was seen in the specimens of seborrheic keratosis. The degree of the expression of STAT3 in SCCs was much stronger than that in the keratoacanthomas and BCCs, with statistical significance (p<0.05).
CONCLUSION
These findings provide the roll of STAT3 in the loss of differentiation and the dysplasia of skin tumors. STAT3 is also thought to have an association with the invasion and metastasis of SCC.